WorldWideScience

Sample records for classes of materials

  1. A new class of spontaneously polarized materials

    DEFF Research Database (Denmark)

    Field, David; Plekan, Oksana; Cassidy, Andrew;

    2011-01-01

    Very large electric fields form spontaneously within films of seemingly prosaic chemicals such as nitrous oxide or propane.We describe how the discovery of this unexpected phenomenon took place and how we attempt to understand the nature of the new class of spontaneously polarized materials...

  2. Silicon carbonitrides - A novel class of materials

    OpenAIRE

    SchÖnfelder, H.; Aldinger, F.; R. Riedel

    1993-01-01

    Silicon carbonitride monoliths derived from polymer powder compacts via polymer pyrolysis represent a new class of structural ceramic materials due to the complete coalescence of the powder particles during polymer decomposition and the formation of a uniform ceramic matrix free from any grain boundaries or secondary phases. The submicron pore channel system penetrating the material can be minimized in volume by infiltration of liquid polysilazane solution or by post-HIPing so that relative d...

  3. Silicon carbonitrides - a novel class of materials

    International Nuclear Information System (INIS)

    Silicon carbonitride monoliths derived from polymer powder compacts via polymer pyrolysis represent a new class of structural ceramic materials due to the complete coalescence of the powder particles during polymer decomposition and the formation of a uniform ceramic matrix free from any grain boundaries or secondary phases. The submicron pore channel system penetrating the material can be minimized in volume by infiltration of liquid polysilazane solution or by post-HIPing so that relative densities of 96 % can be reached. The monoliths are oxidation resistant up to 1600 C in air due to the formation of a highly pure silica oxidation layer and they exhibit a creep rate of 1.10-6 s-1 at 1650 C and 30 MPa load. Initially x-ray amorphous silicon carbonitride can be crystallized in nitrogen or in air to form Si3N4/SiC or Si3N4/SiC/C nanocomposites. (orig.)

  4. 49 CFR 176.144 - Segregation of Class 1 (explosive) materials.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Segregation of Class 1 (explosive) materials. 176... VESSEL Detailed Requirements for Class 1 (Explosive) Materials Segregation § 176.144 Segregation of Class...) Segregation on deck: When Class 1 (explosive) materials in different compatibility groups are carried on...

  5. 49 CFR 176.140 - Segregation from other classes of hazardous materials.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Segregation from other classes of hazardous... CARRIAGE BY VESSEL Detailed Requirements for Class 1 (Explosive) Materials Segregation § 176.140 Segregation from other classes of hazardous materials. (a) Class 1 (explosive) materials must be...

  6. Metal-metalloporphyrin frameworks: a resurging class of functional materials.

    Science.gov (United States)

    Gao, Wen-Yang; Chrzanowski, Matthew; Ma, Shengqian

    2014-08-21

    This review presents comprehensively recent progress in metal-metalloporphyrin frameworks (MMPFs) with an emphasis on versatile functionalities. Following a brief introduction of basic concepts and the potential virtues of MMPFs, we give a snapshot of the historical perspective of MMPFs since 1991. We then summarize four effective strategies implemented frequently to construct prototypal MMPFs. MMPFs represent a resurging class of promising functional materials, highlighted with diverse applications including guest-molecule adsorption and separation, catalysis, nano-thin films and light-harvesting. PMID:24676096

  7. 49 CFR 176.174 - Transport of Class 1 (explosive) materials in shipborne barges.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Transport of Class 1 (explosive) materials in... REGULATIONS CARRIAGE BY VESSEL Detailed Requirements for Class 1 (Explosive) Materials Cargo Transport Units and Shipborne Barges § 176.174 Transport of Class 1 (explosive) materials in shipborne barges....

  8. 49 CFR 176.170 - Transport of Class 1 (explosive) materials in freight containers.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Transport of Class 1 (explosive) materials in... REGULATIONS CARRIAGE BY VESSEL Detailed Requirements for Class 1 (Explosive) Materials Cargo Transport Units and Shipborne Barges § 176.170 Transport of Class 1 (explosive) materials in freight containers....

  9. 49 CFR 176.166 - Transport of Class 1 (explosive) materials on passenger vessels.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Transport of Class 1 (explosive) materials on....166 Transport of Class 1 (explosive) materials on passenger vessels. (a) Only the following Class 1 (explosive) materials may be transported as cargo on passenger vessels: (1) Division 1.4...

  10. 49 CFR 176.168 - Transport of Class 1 (explosive) materials in vehicle spaces.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Transport of Class 1 (explosive) materials in... REGULATIONS CARRIAGE BY VESSEL Detailed Requirements for Class 1 (Explosive) Materials Cargo Transport Units and Shipborne Barges § 176.168 Transport of Class 1 (explosive) materials in vehicle spaces. (a)...

  11. Class Dismissed? Historical Materialism and the Politics of "Difference"

    Science.gov (United States)

    Scatamburlo-D'Annibale, Valerie; McLaren, Peter

    2004-01-01

    Perhaps one of the most taken-for-granted features of contemporary social theory is the ritual and increasingly generic critique of Marxism in terms of its alleged failure to address forms of oppression other than that of "class." Marxism is considered to be theoretically bankrupt and intellectually passe, and class analysis is often savagely…

  12. 27 CFR 555.202 - Classes of explosive materials.

    Science.gov (United States)

    2010-04-01

    ... as UN0333, UN0334, or UN0335 by the U.S. Department of Transportation regulations at 49 CFR 172.101... 27 Alcohol, Tobacco Products and Firearms 3 2010-04-01 2010-04-01 false Classes of explosive..., FIREARMS, AND EXPLOSIVES, DEPARTMENT OF JUSTICE EXPLOSIVES COMMERCE IN EXPLOSIVES Storage § 555.202...

  13. The Effectiveness of Using Student-Generated Materials in Class

    OpenAIRE

    Casey, BEAN

    2015-01-01

    Peer teaching and student-generated materials are two techniques that fall under the umbrella of “collaborative learning.” These activities offer a host of benefits for students that can help them become better second language speakers and moreautonomous learners. This paper will detail the “Worksheet Project,” an activity that integrates both peer teaching and student-generated materials. It will also discuss student reactions to the Worksheet Project, and offer analysis on how to improve fu...

  14. Ferroelectric Rashba Semiconductors as a novel class of multifunctional materials

    Directory of Open Access Journals (Sweden)

    SilviaPicozzi

    2014-02-01

    Full Text Available The discovery of novel properties, effects or microscopic mechanisms in modern materials science is often driven by the quest for combining, into a single compound, several functionalities: not only the juxtaposition of the latter functionalities, but especially their coupling, can open new horizons in basic condensed matter physics as well as in technology. Semiconductor spintronics makes no exception. In this context, we have discovered by means of density-functional simulations that, when a sizeable spin-orbit coupling is combined with ferroelectricity, such as in GeTe, one obtains novel multifunctional materials - called Ferro-Electric Rashba Semi-Conductors (FERSC - where, thanks to a giant Rashba spin-splitting, the spin texture is controllable and switchable via an electric field. This peculiar spin-electric coupling can find a natural playground in small-gap insulators, such as chalcogenides, and can bring brand new assets into the field of electrically-controlled semiconductor spintronics.

  15. Aptitude test and classification of materials with class width of statistically evaluated distinction

    International Nuclear Information System (INIS)

    Classification into classes of statistically evaluated distinction is an appropriate means of assigning various materials properties simply and quickly into the relevant groups of being equivalent or different. This information, however, is subject to statistical uncertainties due to the relatively small number of samples used for materials properties testing; the large variety of materials properties modify the information on possible differences. One factor to be taken into account in determining the class width is a sufficient probability by which a difference between two materials properties can be stated when the average sample data are differing by one or more class widths. For this case, formulas for determining the required class widths, derived by a test well-known in statistical mathematics, are presented in this paper and described by numerical examples. (orig./RW)

  16. Aptitude test and classification of materials with class width of statistically evaluated distinction

    Energy Technology Data Exchange (ETDEWEB)

    Struck, W.

    1982-08-01

    Classification into classes of statistically evaluated distinction is an appropriate means of assigning various materials properties simply and quickly into the relevant groups of being equivalent or different. This information, however, is subject to statistical uncertainties due to the relatively small number of samples used for materials properties testing; the large variety of materials properties modify the information on possible differences. One factor to be taken into account in determining the class width is a sufficient probability by which a difference between two materials properties can be stated when the average sample data are differing by one or more class widths. For this case, formulas for determining the required class widths, derived by a test well-known in statistical mathematics, are presented in this paper and described by numerical examples.

  17. Glass-ceramics: A class of nanostructured materials for photonics

    International Nuclear Information System (INIS)

    Glass-ceramics (GCs) are constituted by nanometer–to–micron-sized crystals embedded in a glass matrix; usually, their structural or functional elements (clusters, crystallites or molecules) have dimensions in the 1 to 100 nm range. As the name says, GCs must be considered an intermediate material between inorganic glasses and ceramics; in most cases the crystallinity is between 30 and 50%. GCs share many properties with both glasses and ceramics, offering low defects, extra hardness, high thermal shock resistance (typical of ceramics) together with the ease of fabrication and moulding (typical of glasses). The embedded crystalline phase, however, can enhance the existing properties of the matrix glass or lead to entirely new properties. GCs are produced by controlled crystallization of certain glasses, generally induced by nucleating additives; they may result opaque or transparent. Transparent GCs are now gaining a competitive advantage with respect to amorphous glasses and, sometimes, to crystals too. The aim of the present paper is to introduce the basic characteristics of transparent glass-ceramics, with particular attention to the relationship between structure and transparency and to the mechanism of crystallization, which may also be induced by selective laser treatments. Their applications to the development of guided-wave structures are also briefly described.

  18. Glass-ceramics: A class of nanostructured materials for photonics

    Science.gov (United States)

    de Pablos-Martin, A.; Ferrari, M.; Pascual, M. J.; Righini, G. C.

    2015-07-01

    Glass-ceramics (GCs) are constituted by nanometer-to-micron-sized crystals embedded in a glass matrix; usually, their structural or functional elements (clusters, crystallites or molecules) have dimensions in the 1 to 100nm range. As the name says, GCs must be considered an intermediate material between inorganic glasses and ceramics; in most cases the crystallinity is between 30 and 50%. GCs share many properties with both glasses and ceramics, offering low defects, extra hardness, high thermal shock resistance (typical of ceramics) together with the ease of fabrication and moulding (typical of glasses). The embedded crystalline phase, however, can enhance the existing properties of the matrix glass or lead to entirely new properties. GCs are produced by controlled crystallization of certain glasses, generally induced by nucleating additives; they may result opaque or transparent. Transparent GCs are now gaining a competitive advantage with respect to amorphous glasses and, sometimes, to crystals too. The aim of the present paper is to introduce the basic characteristics of transparent glass-ceramics, with particular attention to the relationship between structure and transparency and to the mechanism of crystallization, which may also be induced by selective laser treatments. Their applications to the development of guided-wave structures are also briefly described.

  19. Bulk metallic glasses: A new class of engineering materials

    Indian Academy of Sciences (India)

    Joysurya Basu; S Ranganathan

    2003-06-01

    Bulk glass-forming alloys have emerged over the past fifteen years with attractive properties and technological promise. A number of alloy systems based on lanthanum, magnesium, zirconium, palladium, iron, cobalt and nickel have been discovered. Glass-forming ability depends on various factors like enthalpy of mixing, atomic size and multicomponent alloying. A number of processes is available to synthesise bulk metallic glasses. The crystallisation behaviour and mechanical properties of these alloys pose interesting scientific questions. Upon crystallisation many of these glasses transform to bulk nanocrystals and nanoquasicrystals. A detailed study of the structure and the crystallisation behaviour of glasses has enabled the elucidation of the possible atomic configuration in liquid alloys. Their crystallisation behaviour can be exploited to synthesise novel nanocomposite microstructures and their mechanical properties can be enhanced. A broad overview of the present status of the science and technology of bulk metallic glasses and their potential technological uses is presented.

  20. 49 CFR 174.201 - Class 2 (gases) material cylinders.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Class 2 (gases) material cylinders. 174.201... RAIL Detailed Requirements for Class 2 (Gases) Materials § 174.201 Class 2 (gases) material cylinders. (a) Except as provided in paragraphs (b) and (c) of this section, cylinders containing Class 2...

  1. Immunity induced by a broad class of inorganic crystalline materials is directly controlled by their chemistry

    NARCIS (Netherlands)

    G.R. Williams (Gareth); K. Fierens (Kaat); S.G. Preston (Stephen); A.C. Lunn; O. Rysnik (Oliwia); S. de Prijck (Sofie); M. Kool (Mirjam); H.C. Buckley (Hannah); B.N.M. Lambrecht (Bart); D. O'Hare (Dermot); J.M. Austyn (Jonathan)

    2014-01-01

    textabstractThere is currently no paradigm in immunology that enables an accurate prediction of how the immune system will respond to any given agent. Here we show that the immunological responses induced by members of a broad class of inorganic crystalline materials are controlled purely by their p

  2. Electrically based non-destructive microstructural characterization of all classes of materials

    Energy Technology Data Exchange (ETDEWEB)

    Gerhardt, R.A.

    2000-07-01

    This paper gives a short summary of the background, theory and methodology needed to utilize electrical measurements as a non-destructive method for microstructural characterization. Examples are given for all classes of materials. Details are given for how to detect: (1) pore volume in thermal barrier coatings, (2) formation of surface layers due to moisture adsorption in a wide variety of materials, (3) orientation of fibers and whiskers in ceramic matrix and polymer matrix composites, (4) crack detection in metals and (5) stacking faults in semiconductors. Many other examples are mentioned. It needs to be emphasized that electrical measurements alone are not sufficient to identify the microstructural features of interest but must always be accompanied by complementary techniques. Proper data collection and data interpretation of properties of a specific set of materials can lead to in-line process monitoring, quality control monitoring, mechanical damage monitoring and environmental degradation monitoring of those materials.

  3. A new class of low compressibility materials: Clathrates of silicon and related materials

    OpenAIRE

    San Miguel, Alfonso; Mélinon, Patrice; Blase, Xavier; Tournus, Florent; Connétable, Damien; Reny, Édouard; Yamanaka, Shoji; Itié, Jean-Paul; Cros, Christian; Pouchard, Michel

    2002-01-01

    We discuss the high pressure properties of different silicon clathrate structures that we have investigated by means of X-ray diffraction and ab initio calculations. Compressibility transition pressures or phase transformations are interpreted as a function of the nature of the guest atom intercalation, The compressibility of the clathrate structure is in all cases close to that of silicon diamond whereas transition pressures or the high pressure phases are extremely depending on the nature o...

  4. 49 CFR 177.838 - Class 4 (flammable solid) materials, Class 5 (oxidizing) materials, and Division 4.2 (pyroforic...

    Science.gov (United States)

    2010-10-01

    ..., see the List of CFR Sections Affected which appears in the Finding Aids section of the printed volume... (oxidizing) materials, and Division 4.2 (pyroforic liquid) materials. 177.838 Section 177.838 Transportation... § 177.838 Class 4 (flammable solid) materials, Class 5 (oxidizing) materials, and Division...

  5. 49 CFR 177.842 - Class 7 (radioactive) material.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Class 7 (radioactive) material. 177.842 Section 177.842 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS MATERIALS... HIGHWAY Loading and Unloading § 177.842 Class 7 (radioactive) material. (a) The number of packages...

  6. Optimization of a class of latent thermal energy storage systems with multiple phase-change materials

    Energy Technology Data Exchange (ETDEWEB)

    Aceves, S.M. [Lawrence Livermore National Lab., CA (United States); Nakamura, H. [Daido Inst. of Tech., Nagoya (Japan). Dept. of Mechanical Engineering; Reistad, G.M. [Oregon State Univ., Corvallis, OR (United States). Dept. of Mechanical Engineering; Martinez-Frias, J. [Centro de Ingenieria y Desarollo Industrial, Queretaro (Mexico)

    1998-02-01

    This paper presents an analysis of a class of latent thermal energy storage (LTES) system. The analysis is based on a simplified model that allows the system performance to be evaluated in terms of a small set of parameters, while still retaining the main thermodynamic aspects associated with their operation. This analysis therefore permits the broad-based application potential of these systems to be viewed. The paper also discusses the applicability of the model to practical systems. This paper analyzes LTES with multiple energy storage cells and multiple phase-change materials (PCMs). The most general case of infinite energy storage cells and PCMs is solved, for the charge process only, as well as for the overall charge-discharge process. The results yield the optimum phase change temperature, expressed as a continuous function of position along the LTES. The method is equally applicable to the case of a finite number of storage cells. An example of the application of the method to this case is also included. The results show the optimum phase change temperatures for each of the problems being considered, along with the corresponding optimum exergetic efficiencies. The solutions to the optimization problems are surprisingly simple to express, considering the difficulty of the problems, and indicate the potential advantages of using LTES with multiple PCMs.

  7. 49 CFR 177.840 - Class 2 (gases) materials.

    Science.gov (United States)

    2010-10-01

    ..., see the List of CFR Sections Affected which appears in the Finding Aids section of the printed volume... 49 Transportation 2 2010-10-01 2010-10-01 false Class 2 (gases) materials. 177.840 Section 177.840... and Unloading § 177.840 Class 2 (gases) materials. (See also § 177.834 (a) to (j).) (a) Floors...

  8. 49 CFR 177.835 - Class 1 materials.

    Science.gov (United States)

    2010-10-01

    ..., see the List of CFR Sections Affected which appears in the Finding Aids section of the printed volume... 49 Transportation 2 2010-10-01 2010-10-01 false Class 1 materials. 177.835 Section 177.835... and Unloading § 177.835 Class 1 materials. (See also § 177.834 (a) to (j).) (a) Engine stopped....

  9. 49 CFR 177.837 - Class 3 materials.

    Science.gov (United States)

    2010-10-01

    .... Editorial Note: For Federal Register citations affecting § 177.837, see the List of CFR Sections Affected... 49 Transportation 2 2010-10-01 2010-10-01 false Class 3 materials. 177.837 Section 177.837... and Unloading § 177.837 Class 3 materials. (See also § 177.834 (a) to (j).) (a) Engine stopped....

  10. Development of pupils’ transfer skills by means of hands’ on activities with artisan materials in natural sciences classes

    OpenAIRE

    Liliana Ciascai; Luminiţa Chicinaş

    2008-01-01

    Hands’ on activities with artisan materials used in order to realize different practical devices helpful in learning process are one of the most frequently used activity in science classes. Usually, the main strengthnesses of these activities are: a deeper learning, an increased motivation of pupils for actively learning and development of practical skills. The aim of our paper is to find out if using systematically hands’ on activities in order to realize different practical devices contribu...

  11. Electronic properties of SnTe-class topological crystalline insulator materials

    OpenAIRE

    Wang, Jianfeng; Wang, Na; Huang, Huaqing; Duan, Wenhui

    2016-01-01

    The rise of topological insulators in recent years has broken new ground both in the conceptual cognition of condensed matter physics and the promising revolution of the electronic devices. It also stimulates the explorations of more topological states of matter. Topological crystalline insulator is a new topological phase, which combines the electronic topology and crystal symmetry together. In this article, we review the recent progress in the studies of SnTe-class topological crystalline i...

  12. 49 CFR 174.101 - Loading Class 1 (explosive) materials.

    Science.gov (United States)

    2010-10-01

    ... internal combustion engine in its operation. (m) (n) A container car or freight container on a flatcar or a... this subchapter, applicable to shipments of Class 1 (explosive) materials by motor vehicle. (2)...

  13. The Use of Supplementary Materials in English Foreign Language Classes in Ecuadorian Secondary Schools

    Science.gov (United States)

    Dodd, Alexander R.; Camacho, Gina K.; Morocho, Elsa L.; Paredes, Fabián M.; Zúñiga, Alexandra; Pinza, Eliana I.; Toro, Lisset V.; Vargas, Alba B.; Benítez, Carmen D.; Rogers, Sylvia

    2015-01-01

    This mixed-methods study investigated the use of supplementary materials by EFL teachers in Ecuadorian secondary schools. Via the use of teacher interviews (n = 12) it was found that teachers believe the use of supplementary materials increases the motivation of the students, which in-turn improves the learning possibilities of the students. The…

  14. Evaluation of a class of polyurethane materials for intraocular lens manufacturing.

    Science.gov (United States)

    Bozukova, Dimitriya; Bertrand, Virginie; Pagnoulle, Christophe; De Pauw-Gillet, Marie-Claire

    2015-08-01

    Ophthalmic lenses are medical devices with considerable requirements in terms of optical, biomechanical and biological performance. There is limited number of materials used for their manufacturing, comprising mainly silicones and poly(meth)acrylates. This series of publications aims at investigating the applicability of thermoplastic polyurethane elastomers (TPU) for the manufacturing of ophthalmic lenses and examining the properties of the respective devices. This study is related to the synthesis of TPUs with chemical compositions that comprise chemically grafted filters for the hazardous-light. GC-MS, attenuated total reflectance Fourier transform infrared spectroscopy, and UV-vis spectroscopies confirmed the reaction completion and the beneficial effect of the filters on the light transmittance, respectively. Relatively high refractive index of the material was measured and allows for the manufacturing of thinner lenses. The contrast sensitivity determined for a model intraocular lens (IOL) was satisfactory. Few optical defects were, however, present on the model lens prepared by thermoplastic injection molding. The elasticity of the materials was evaluated in view to their potential applicability as foldable IOLs by determining their glass transition temperature and their Young modulus and measuring their shore A. The TPU materials demonstrated more bioadhesive character compared with a benchmark hydrophilic acrylic reference material, which is already used for IOL manufacturing. PMID:25352276

  15. Influence of Class I interferons on performance of vascular cells on stent material in vitro

    International Nuclear Information System (INIS)

    Purpose: Numerous reports suggest that Class 1 interferons (IFNs), particularly IFN-γ, inhibit migration and proliferation of different types of human cells. The objective of the present study was to determine the effect of Class I IFNs on viability and growth characteristics of human aortic endothelial cells (ECs), smooth muscle cells (SMC) and fibroblasts (FBs) in vitro. Methods: Stainless-steel (316-l) disks were coated with fibrin meshwork containing IFN-γ or IFN-α. The discs and IFN embedded meshwork were incubated with human EC, SMC and FB, and then cultured, whereas control cells were seeded onto uncoated surfaces or plain fibrin meshwork. Concentrations of recombinant IFN varied from 5 to 20 ng/cm2. Assessment of effect on cell viability, growth and attachment was performed utilizing Alamar Blue (AB) assay. Cell morphology was assessed by scanning electron microscopy (SEM). Results: We have now shown inhibitory capacity of IFN-γ on all three types of unstimulated cells. The growth-inhibitory effect was maximal with SMC, while it was minimal with FB and EC. IFN-γ abrogated mitogenic responses of SMC but not EC and partially FB to VEGF and FGF stimulation. IFN-α was able to inhibit EC growth and, to a lesser extent, FB, and did influence growth rates of SMC. Biochemical analysis of lactate dehydrogenase activity suggested that IFN was not toxic to vascular cells. We also measured the expression of cell adhesive molecules: P- and E-selections, PECAM and ICAM-1. These molecules were upregulated by IFN in EC. Media derived from quiescent human SMC displayed low immunoreactive elastase activity, while conditional media after IFN-γ treatment but not IFN-α treatment had approximately a threefold greater activity. Conclusion: These data suggest that IFN-γ significantly inhibits SMC growth in the absence of significant endothelial toxicity and is dose-dependent; however, animal experiments are needed to further explore the antirestenotic effects of IFNs

  16. A New Class of High Z Nanocrystalline and Textured Oxide-Based Thermoelectric Material Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose to develop high figure of merit (ZT) oxide-based thermoelectric materials. This will be accomplished by engineering a novel microstructure that will lead...

  17. Metal azides under pressure: An emerging class of high energy density materials

    Indian Academy of Sciences (India)

    G Vaitheeswaran; K Ramesh Babu

    2012-11-01

    Metal azides are well-known for their explosive properties such as detonation or deflagration. As chemically pure sources of nitrogen, alkali metal azides under high pressure have the ability to form polymeric nitrogen, an ultimate green high energy density material with energy density three times greater than that of known high energetic materials. With this motive, in this present work, we try to address the high-pressure behaviour of LiN3 and KN3 by means of density functional calculations. All the calculations are performed with the inclusion of van derWaals interactions at semi empirical level, as these materials are typical molecular solids. We found that both LiN3 and KN3 are structurally stable up to the studied pressure range of 60 GPa and 16 GPa, respectively. At ambient conditions both the materials are insulators with a gap of 3.48 eV (LiN3) and 4.08 eV (KN3) and as pressure increases the band gap decreases and show semiconducting nature at high pressures.We also found that the compressibility of both the crystals is anisotropic which is in good agreement with experiment. Our theoretical study proved that the materials under study may have the ability to form polymeric nitrogen because of the decrease in interazide ion distance and possible overlapping of N atomic orbitals.

  18. New Class of High-Energy Transients from Crashes of Supernova Ejecta with Massive Circumstellar Material Shells

    OpenAIRE

    Murase, Kohta; Thompson, Todd A.; Lacki, Brian C.; Beacom, John F.

    2010-01-01

    A new class of core-collapse supernovae (SNe) has been discovered in recent years by optical/infrared surveys; these SNe suggest the presence of one or more extremely dense (~10^5-10^11 cm^-3) shells of circumstellar material (CSM) on 10^2-10^4 AU scales. We consider the collisions of the SN ejecta with these massive CSM shells as potential cosmic-ray (CR) accelerators. If ~10% of the SN energy goes into CRs, multi-TeV neutrinos and/or GeV-TeV gamma rays almost simultaneous with the optical/i...

  19. Impact of Adaptive Materials on Teachers and their Students with Visual Impairments in Secondary Science and Mathematics Classes

    Science.gov (United States)

    Rule, Audrey C.; Stefanich, Greg P.; Boody, Robert M.; Peiffer, Belinda

    2011-04-01

    Science, technology, engineering, and mathematics (STEM) fields, important in today's world, are underrepresented by students with disabilities. Students with visual impairments, although cognitively similar to sighted peers, face challenges as STEM subjects are often taught using visuals. They need alternative forms of access such as enlarged or audio-converted text, tactile graphics, and involvement in hands-on science. This project focused on increasing teacher awareness of and providing funds for the purchase of supplemental adaptive resources, supplies, and equipment. We examined attitude and instructional changes across the year of the programme in 15 science and mathematics teachers educating students with visual impairments. Positive changes were noted from pretest to posttest in student and teacher perspectives, and in teacher attitudes towards students with disabilities in STEM classes. Teachers also provided insights into their challenges and successes through a reflective narrative. Several adolescent students resisted accommodations to avoid appearing conspicuous to peers. Teachers implemented three strategies to address this: providing the adaptations to all students in the class; convincing the student of the need for adaptation; and involving the class in understanding and accepting the student's impairment. A variety of teacher-created adaptations for various science and mathematics labs are reported. Another finding was many adaptations provided for the student with visual impairment benefitted the entire class. This study supports the claim that given knowledgeable, supportive teachers, and with appropriate accommodations such as tactile or auditory materials, students with visual impairments can be as successful and engaged as other students in science and mathematics.

  20. Studies on two classes of positive electrode materials for lithium-ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Wilcox, James Douglas [Univ. of California, Berkeley, CA (United States)

    2008-12-01

    The development of advanced lithium-ion batteries is key to the success of many technologies, and in particular, hybrid electric vehicles. In addition to finding materials with higher energy and power densities, improvements in other factors such as cost, toxicity, lifetime, and safety are also required. Lithium transition metal oxide and LiFePO4/C composite materials offer several distinct advantages in achieving many of these goals and are the focus of this report. Two series of layered lithium transition metal oxides, namely LiNi1/3Co1/3-yMyMn1/3O2 (M=Al, Co, Fe, Ti) and LiNi0.4Co0.2-yMyMn0.4O2 (M = Al, Co, Fe), have been synthesized. The effect of substitution on the crystal structure is related to shifts in transport properties and ultimately to the electrochemical performance. Partial aluminum substitution creates a high-rate positive electrode material capable of delivering twice the discharge capacity of unsubstituted materials. Iron substituted materials suffer from limited electrochemical performance and poor cycling stability due to the degradation of the layered structure. Titanium substitution creates a very high rate positive electrode material due to a decrease in the anti-site defect concentration. LiFePO4 is a very promising electrode material but suffers from poor electronic and ionic conductivity. To overcome this, two new techniques have been developed to synthesize high performance LiFePO4/C composite materials. The use of graphitization catalysts in conjunction with pyromellitic acid leads to a highly graphitic carbon coating on the surface of LiFePO4 particles. Under the proper conditions, the room temperature electronic conductivity can be improved by nearly five orders of magnitude over untreated materials. Using Raman spectroscopy, the improvement in conductivity and rate performance of

  1. STUDIES ON TWO CLASSES OF POSITIVE ELECTRODE MATERIALS FOR LITHIUM-ION BATTERIES

    Energy Technology Data Exchange (ETDEWEB)

    Wilcox, James D.

    2008-12-18

    The development of advanced lithium-ion batteries is key to the success of many technologies, and in particular, hybrid electric vehicles. In addition to finding materials with higher energy and power densities, improvements in other factors such as cost, toxicity, lifetime, and safety are also required. Lithium transition metal oxide and LiFePO{sub 4}/C composite materials offer several distinct advantages in achieving many of these goals and are the focus of this report. Two series of layered lithium transition metal oxides, namely LiNi{sub 1/3}Co{sub 1/3-y}M{sub y}Mn{sub 1/3}O{sub 2} (M=Al, Co, Fe, Ti) and LiNi{sub 0.4}Co{sub 0.2-y}M{sub y}Mn{sub 0.4}O{sub 2} (M = Al, Co, Fe), have been synthesized. The effect of substitution on the crystal structure is related to shifts in transport properties and ultimately to the electrochemical performance. Partial aluminum substitution creates a high-rate positive electrode material capable of delivering twice the discharge capacity of unsubstituted materials. Iron substituted materials suffer from limited electrochemical performance and poor cycling stability due to the degradation of the layered structure. Titanium substitution creates a very high rate positive electrode material due to a decrease in the anti-site defect concentration. LiFePO{sub 4} is a very promising electrode material but suffers from poor electronic and ionic conductivity. To overcome this, two new techniques have been developed to synthesize high performance LiFePO{sub 4}/C composite materials. The use of graphitization catalysts in conjunction with pyromellitic acid leads to a highly graphitic carbon coating on the surface of LiFePO{sub 4} particles. Under the proper conditions, the room temperature electronic conductivity can be improved by nearly five orders of magnitude over untreated materials. Using Raman spectroscopy, the improvement in conductivity and rate performance of such materials has been related to the underlying structure of the

  2. Applications of a 3MV class electron microscope to materials science

    International Nuclear Information System (INIS)

    Applications of a 3 MV class electron microscope have been examined over the voltage range 0.5 to 3 MV. In metals such as Al, Cu, Fe, Mo, W, and Au the following phenomena have been investigated: (a) voltage dependence of the maximum observable thickness for dislocation images; it is shown that the maximum observable thickness at 2 to 3 MV is larger than the critical foil thickness, which is sufficient to observe the same phenomena as in bulk specimens, even in such heavy metals at W and Au; (b) the critical voltage of anomalous transmission of electrons at the symmetry position of reflections, which is correlated with an electron channelling parameter; (c) electron irradiation damage, which is sensitive to the crystallographic condition of the specimens as well as to the accelerating voltage. Furthermore, the use of capsules has also been examined for the determination of liquid structure, of diffusion constants, of boundary diffusion, and of pipe diffusion along dislocation lines, and for observations of the sintering process in metal powders. (author)

  3. Sulfurized carbon: a class of cathode materials for high performance lithium/sulfur batteries

    Directory of Open Access Journals (Sweden)

    Sheng S. Zhang

    2013-12-01

    Full Text Available Liquid electrolyte lithium/sulfur (Li/S batteries cannot come into practical applications because of many problems such as low energy efficiency, short cycle life, and fast self-discharge. All these problems are related to the dissolution of lithium polysulfide, a series of sulfur reduction intermediates, in the liquid electrolyte, and resulting parasitic reactions with the Li anode. Covalently binding sulfur onto carbon surface is a solution to completely eliminate the dissolution of lithium polysulfide and make the Li/S battery viable for practical applications. This can be achieved by replacing elemental sulfur with sulfurized carbon as the cathode material. This article reviews the current efforts on this subject and discusses the syntheses, electrochemical properties, and prospects of the sulfurized carbon as a cathode material in the rechargeable Li/S batteries.

  4. Lightweight constructions made of polymer materials. Classes - applications - trends; Leichtbau mit polymeren Werkstoffen. Klassen - Anwendungen - Tendenzen

    Energy Technology Data Exchange (ETDEWEB)

    Meij, A. [Fachhochschule Kaiserslautern (Germany)

    2000-07-01

    The properties of polymer (composite) materials can be tailored to the specific requirements in service. This tailoring offers sheer unnumerable variations of materials and processing methods. A classification scheme is introduced to reduce this number of possible variations to a limited group of essential characteristics. Typical consequences for the properties and the processing of this material variations are described. The classification scheme also reveals 'white spots' in the application of engineering plastics. Development of new materials and combinations can thus be initiated more target-oriented. Consequently fabric reinforced thermoplastics are regarded as an example to raise today's volume in high-end composites. Pros and cons of these fabric reinforced plastics are mentioned. It is shown, that a synergy between the 'classical' plastics processing technology of the one hand and the composites technology on the other hand can boost new applications of structural polymer parts. (orig.) [German] Die technische Entwicklung der Menschheit wird seit jeher von der Verfuegbarkeit geeigneter Werkstoffe mitbestimmt. Je nach Anforderung verlangen Konstrukteure Werkstoffe mit unterschiedlichen Eigenschaftsprofilen, z.B. steif und fest oder weich und fest. Am besten, es gaebe einen Werkstoff, dessen Eigenschaften in allen Hinsichten frei 'einstellbar' waeren. Polymere Werkstoffe erfuellen diesen Wunsch selbstverstaendlich nicht, dennoch erstrecken die durch Modifikation erreichbaren Kennwerte sich ueber einen ausserordentlich grossen Bereich. Betrachtet man die polymeren Schaeume, die Elastomere, die technischen Kunststoffe und die Faserverbundwerkstoffe zusammen, so erstrecken sich sowohl die Festigkeit als auch die Steifigkeit ueber vier Dekaden. Auch die Zaehigkeit und die Dichte koennen weitgehend frei variiert werden. In diesem Beitrag sollen nun weiter einige Gedanken zum Eigenschafts-, Anwendungs- und Verarbeitungsprofil von

  5. Hydrogen-Bonded Organic Frameworks (HOFs): A New Class of Porous Crystalline Proton-Conducting Materials.

    Science.gov (United States)

    Karmakar, Avishek; Illathvalappil, Rajith; Anothumakkool, Bihag; Sen, Arunabha; Samanta, Partha; Desai, Aamod V; Kurungot, Sreekumar; Ghosh, Sujit K

    2016-08-26

    Two porous hydrogen-bonded organic frameworks (HOFs) based on arene sulfonates and guanidinium ions are reported. As a result of the presence of ionic backbones appended with protonic source, the compounds exhibit ultra-high proton conduction values (σ) 0.75× 10(-2)  S cm(-1) and 1.8×10(-2)  S cm(-1) under humidified conditions. Also, they have very low activation energy values and the highest proton conductivity at ambient conditions (low humidity and at moderate temperature) among porous crystalline materials, such as metal-organic frameworks (MOFs) and covalent organic frameworks (COFs). These values are not only comparable to the conventionally used proton exchange membranes, such as Nafion used in fuel cell technologies, but is also the highest value reported in organic-based porous architectures. Notably, this report inaugurates the usage of crystalline hydrogen-bonded porous organic frameworks as solid-state proton conducting materials. PMID:27464784

  6. A new class of bio-composite materials of unique collagen fibers.

    Science.gov (United States)

    Sharabi, Mirit; Mandelberg, Yael; Benayahu, Dafna; Benayahu, Yehuda; Azem, Abdussalam; Haj-Ali, Rami

    2014-08-01

    A novel collagen-based bio-composite was constructed from micro-crimped long collagen fiber bundles extracted from a soft coral embedded in alginate hydrogel matrix. The mechanical features of this bio-composite were studied for different fiber fractions and in longitudinal and transverse loading modes. The tensile modulus of the alginate hydrogel was 0.60±0.35MPa and in longitudinal collagen-reinforced construct it increased up to 9.71±2.80 for 50% fiber fraction. Ultimate tensile strength was elevated from 0.08±0.04MPa in matrix up to 1.21±0.29 for fiber fraction of 30%. The bio-composite demonstrated hyperelastic behavior similar to human native tissues. Additionally, a dedicated constitutive material model was developed to enable the prediction of the longitudinal mechanical behavior of the bio-composite. These findings will allow tailor-designed mechanical properties with a quantitatively controlled amount of fibers and their designed spatial arrangement. This unique bio-composite has the potential to be used for a wide range of engineered soft tissues. PMID:24801102

  7. Two classes of superconductors discovered in our material research: Iron-based high temperature superconductor and electride superconductor

    International Nuclear Information System (INIS)

    We discovered two new classes of superconductors in the course of material exploration for electronic-active oxides. One is 12CaO . 7Al2O3 crystal in which electrons accomodate in the crystallographic sub-nanometer-sized cavities. This material exhibiting metal-superconductor transition at 0.2 K is the first electride superconductor. The other is iron oxypnicitides with a layered structure. This superconductor is rather different from high Tc cuprates in several respects. The high Tc is emerged by doping carriers to the metallic parent phases which undergo crystallographic transition (tetra to ortho) and Pauli para to antiferromagnetic transition at ∼150 K. The Tc is robust to impurity doping to the Fe sites or is induced by partial substitution of the Fe2+ sites with Co2+ or Ni2+. This article gives a brief summary of these discoveries and recent advances.

  8. Existence result for a class of generalized standard materials with thermomechanical coupling

    CERN Document Server

    Paoli, Laetitia

    2011-01-01

    This paper deals with the study of a three-dimensional model of thermomechanical coupling for viscous solids exhibiting hysteresis effects. This model is written in accordance with the formalism of generalized standard materials and it is composed of the momentum equilibrium equation combined with the flow rule, which describes some stress-strain dependance, coupled to the heat-transfer equation. More precisely, the coupling terms are linear with respect to the temperature and the displacement and non linear with respect to the internal variable. The main mathematical difficulty lies in the fact that the natural framework for the right-hand side of the heat equation is the space of L1 functions. A local existence result for this thermodynamically consistent problem is obtained by using a fixed-point argument. Then the solutions are proved to be physically admissible and global existence is discussed under some additional assumptions on the data.

  9. Physisorption of Nucleic Acid Bases on Boron Nitride Nanotubes: A new class of Hybrid Nano-Bio Materials

    CERN Document Server

    Mukhopadhyay, Saikat; Scheicher, Ralph H; Pandey, Ravindra; Karna, Shashi P

    2009-01-01

    We investigate the adsorption of the nucleic acid bases, adenine (A), guanine (G), cytosine (C), thymine (T) and uracil (U) on the outer wall of a high curvature semiconducting single-walled boron nitride nanotube (BNNT) by first principles density functional theory calculations. The calculated binding energy shows the order: G>A~C~T~U implying that the interaction strength of the (high-curvature) BNNT with the nucleobases, G being an exception, is nearly the same. A higher binding energy for the G-BNNT conjugate appears to result from a stronger hybridization of the molecular orbitals of G and BNNT, since the charge transfer involved in the physisorption process is insignificant. A smaller energy gap predicted for the G-BNNT conjugate relative to that of the pristine BNNT may be useful in application of this class of biofunctional materials to the design of the next generation sensing devices.

  10. Physisorption of Nucleic Acid Bases on Boron Nitride Nanotubes: A new class of Hybrid Nano-Bio Materials

    Science.gov (United States)

    Mukhopadhyay, Saikat; Gowtham, S.; Scheicher, Ralph; Pandey, Ravindra; Karna, Shashi

    2010-03-01

    We investigate the adsorption of the nucleic acid bases, adenine (A), guanine (G), cytosine (C), thymine (T) and uracil (U) on the outer wall of a high curvature semiconducting single-walled boron nitride nanotube (BNNT) by first principles density functional theory calculations. The calculated binding energy shows the order: G>A C T U implying that the interaction strength of the (high-curvature) BNNT with the nucleobases, G being an exception, is nearly the same. A higher binding energy for the G-BNNT conjugate appears to result from a stronger hybridization of the molecular orbitals of G and BNNT, since the charge transfer involved in the physisorption process is insignificant. A smaller energy gap predicted for the G-BNNT conjugate relative to that of the pristine BNNT may be useful in application of this class of biofunctional materials to the design of the next generation sensing devices.

  11. Class Vectors: Embedding representation of Document Classes

    OpenAIRE

    Sachan, Devendra Singh; Kumar, Shailesh

    2015-01-01

    Distributed representations of words and paragraphs as semantic embeddings in high dimensional data are used across a number of Natural Language Understanding tasks such as retrieval, translation, and classification. In this work, we propose "Class Vectors" - a framework for learning a vector per class in the same embedding space as the word and paragraph embeddings. Similarity between these class vectors and word vectors are used as features to classify a document to a class. In experiment o...

  12. Fullerene-ionic-liquid conjugates: a new class of hybrid materials with unprecedented properties.

    Science.gov (United States)

    Campisciano, Vincenzo; La Parola, Valeria; Liotta, Leonarda F; Giacalone, Francesco; Gruttadauria, Michelangelo

    2015-02-16

    A modular approach has been followed for the synthesis of a series of fullerene-ionic-liquid (IL) hybrids in which the number of IL moieties (two or twelve), anion, and cation have been varied. The combination of C60 and IL give rise to new unique properties in the conjugates such as solubility in water, which was higher than 800 mg mL(-1) in several cases. In addition, one of the C60 -IL hybrids has been employed for the immobilization of palladium nanoparticles through ion exchange followed by reduction with sodium borohydride. Surprisingly, during the reduction several carbon nanostructures were formed that comprised nano-onions and nanocages with few-layer graphene sidewalls, which have been characterized by means of thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), scanning electron microscopy/energy-dispersive X-ray analysis (SEM-EDAX), and high-resolution transmission electron microscopy (HRTEM). Finally, the material thus obtained was successfully applied as catalyst in Suzuki and Mizoroki-Heck reactions in a concentration of just 0.2 mol %. In the former process it was recyclable for five runs with no loss in activity. PMID:25589382

  13. 49 CFR 177.839 - Class 8 (corrosive) materials.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Class 8 (corrosive) materials. 177.839 Section 177.839 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS MATERIALS... HIGHWAY Loading and Unloading § 177.839 Class 8 (corrosive) materials. (See also § 177.834(a) through...

  14. The Paradox of Paperless Classes.

    Science.gov (United States)

    Lackie, Paula

    1998-01-01

    Describes paperless classes developed at Carleton College that augment traditional classes by giving students and faculty the ability to share digital course-related materials via the campus computer network. Presents a case study of a managerial economics course, and includes problems with various aspects of the course and solutions. (LRW)

  15. Conceptual design of a 1013 -W pulsed-power accelerator for megajoule-class dynamic-material-physics experiments

    Science.gov (United States)

    Stygar, W. A.; Reisman, D. B.; Stoltzfus, B. S.; Austin, K. N.; Ao, T.; Benage, J. F.; Breden, E. W.; Cooper, R. A.; Cuneo, M. E.; Davis, J.-P.; Ennis, J. B.; Gard, P. D.; Greiser, G. W.; Gruner, F. R.; Haill, T. A.; Hutsel, B. T.; Jones, P. A.; LeChien, K. R.; Leckbee, J. J.; Lewis, S. A.; Lucero, D. J.; McKee, G. R.; Moore, J. K.; Mulville, T. D.; Muron, D. J.; Root, S.; Savage, M. E.; Sceiford, M. E.; Spielman, R. B.; Waisman, E. M.; Wisher, M. L.

    2016-07-01

    We have developed a conceptual design of a next-generation pulsed-power accelerator that is optimized for megajoule-class dynamic-material-physics experiments. Sufficient electrical energy is delivered by the accelerator to a physics load to achieve—within centimeter-scale samples—material pressures as high as 1 TPa. The accelerator design is based on an architecture that is founded on three concepts: single-stage electrical-pulse compression, impedance matching, and transit-time-isolated drive circuits. The prime power source of the accelerator consists of 600 independent impedance-matched Marx generators. Each Marx comprises eight 5.8-GW bricks connected electrically in series, and generates a 100-ns 46-GW electrical-power pulse. A 450-ns-long water-insulated coaxial-transmission-line impedance transformer transports the power generated by each Marx to a system of twelve 2.5-m-radius water-insulated conical transmission lines. The conical lines are connected electrically in parallel at a 66-cm radius by a water-insulated 45-post sextuple-post-hole convolute. The convolute sums the electrical currents at the outputs of the conical lines, and delivers the combined current to a single solid-dielectric-insulated radial transmission line. The radial line in turn transmits the combined current to the load. Since much of the accelerator is water insulated, we refer to it as Neptune. Neptune is 40 m in diameter, stores 4.8 MJ of electrical energy in its Marx capacitors, and generates 28 TW of peak electrical power. Since the Marxes are transit-time isolated from each other for 900 ns, they can be triggered at different times to construct-over an interval as long as 1 μ s -the specific load-current time history required for a given experiment. Neptune delivers 1 MJ and 20 MA in a 380-ns current pulse to an 18 -m Ω load; hence Neptune is a megajoule-class 20-MA arbitrary waveform generator. Neptune will allow the international scientific community to conduct dynamic

  16. Creative experimentation with art materials in art class

    OpenAIRE

    Bajc, Karin

    2015-01-01

    I have divided the graduation thesis titled Creative Experimentation with Art Materials in Art Class into two parts, namely theoretical and empirical part. In the theoretical part, I have researched the term creativity: what is that, how do we encourage creativity in schools, what are the phases of creative thinking. A special attention was paid to the creativity in the field of art; I have described design fields such as drawing, painting, sculpture, graphic design, and architecture in ...

  17. A new class of chiral materials hosting magnetic skyrmions beyond room temperature.

    Science.gov (United States)

    Tokunaga, Y; Yu, X Z; White, J S; Rønnow, H M; Morikawa, D; Taguchi, Y; Tokura, Y

    2015-01-01

    Skyrmions, topologically protected vortex-like nanometric spin textures in magnets, have been attracting increasing attention for emergent electromagnetic responses and possible technological applications for spintronics. In particular, metallic magnets with chiral and cubic/tetragonal crystal structure may have high potential to host skyrmions that can be driven by low electrical current excitation. However, experimental observations of skyrmions have been limited to below room temperature for the metallic chiral magnets, specifically for the MnSi-type B20 compounds. Towards technological applications, transcending this limitation is crucial. Here we demonstrate the formation of skyrmions with unique spin helicity both at and above room temperature in a family of cubic chiral magnets: β-Mn-type Co-Zn-Mn alloys with a different chiral space group from that of B20 compounds. Lorentz transmission electron microscopy, magnetization and small-angle neutron scattering measurements unambiguously reveal formation of a skyrmion crystal under application of a magnetic field in both thin-plate and bulk forms. PMID:26134284

  18. Development of E-Assessment Materials for Fifth Grade Middle School Classes

    OpenAIRE

    Arı, Asım; Tahirova, Esra Eren Şefika Sümeyye Çam Gyuldzhan G

    2014-01-01

    Developments in information and communication technologies affect education with regard to gain the necessary skills for individuals living in technological environment, train manpower having the quality that technological environment requires and benefit from the opportunities of technology. Using more technology in education is thought to increase educational opportunities and quality, contribute to learning by doing and living addressing more senses in teaching-learning process by some res...

  19. Two-dimensional B-C-O alloys: a promising class of 2D materials for electronic devices

    Science.gov (United States)

    Zhou, Si; Zhao, Jijun

    2016-04-01

    Graphene, a superior 2D material with high carrier mobility, has limited application in electronic devices due to zero band gap. In this regard, boron and nitrogen atoms have been integrated into the graphene lattice to fabricate 2D semiconducting heterostructures. It is an intriguing question whether oxygen can, as a replacement of nitrogen, enter the sp2 honeycomb lattice and form stable B-C-O monolayer structures. Here we explore the atomic structures, energetic and thermodynamic stability, and electronic properties of various 2D B-C-O alloys using first-principles calculations. Our results show that oxygen can be stably incorporated into the graphene lattice by bonding with boron. The B and O species favor forming alternate patterns into the chain- or ring-like structures embedded in the pristine graphene regions. These B-C-O hybrid sheets can be either metals or semiconductors depending on the B : O ratio. The semiconducting (B2O)nCm and (B6O3)nCm phases exist under the B- and O-rich conditions, and possess a tunable band gap of 1.0-3.8 eV and high carrier mobility, retaining ~1000 cm2 V-1 s-1 even for half coverage of B and O atoms. These B-C-O alloys form a new class of 2D materials that are promising candidates for high-speed electronic devices.Graphene, a superior 2D material with high carrier mobility, has limited application in electronic devices due to zero band gap. In this regard, boron and nitrogen atoms have been integrated into the graphene lattice to fabricate 2D semiconducting heterostructures. It is an intriguing question whether oxygen can, as a replacement of nitrogen, enter the sp2 honeycomb lattice and form stable B-C-O monolayer structures. Here we explore the atomic structures, energetic and thermodynamic stability, and electronic properties of various 2D B-C-O alloys using first-principles calculations. Our results show that oxygen can be stably incorporated into the graphene lattice by bonding with boron. The B and O species favor

  20. High-performance 193-nm photoresist materials based on a new class of polymers containing spaced ester finctionalities

    Science.gov (United States)

    Khojasteh, Mahmoud; Chen, K. Rex; Kwong, Ranee W.; Lawson, Margaret C.; Varanasi, Pushkara R.; Patel, Kaushal S.; Kobayashi, Eiichi

    2003-06-01

    ArF lithography has been selected as the imaging method for the 90 nm technology node. Manufacturing related issues will have to be addressed when designing advanced 193 nm resists that are production worthy. Post exposure bake (PEB) sensitivity, dissolution properties and process window are some issues that need continuous improvement. Initially our investigation focused on a cyclic olefin (CO) platform which led us to a better understanding of the relationship between polymer structure and physical properties and how to improve cyclic olefin resist performance. Since then we have developed a new class of acrylate polymers with pendant "spaced ester" functionality. We have investigated the potential use of "spaced ester" functionality on improving the lithographic performance of CO and acrylate resist platforms. We have found that with "spaced ester" as pending group in CO polymer structures, it can lower the Tg and improve the dissolution properties of the CO resists. Resists formulated with acrylate containing "spaced ester" group exhibit excellent PEB temperature sensitivity (1 nm/°C), and are soluble in PGMEA. In addition, we have demonstrated sub-100 nm resolution with excellent process window through formulation optimization for acrylate based resists. This paper will focus on the "spaced ester" based polymer design, material properties; resist characteristics, and the lithographic performance for logic dense line applications.

  1. Student versus Faculty Perceptions of Missing Class.

    Science.gov (United States)

    Sleigh, Merry J.; Ritzer, Darren R.; Casey, Michael B.

    2002-01-01

    Examines and compares student and faculty attitudes towards students missing classes and class attendance. Surveys undergraduate students (n=231) in lower and upper level psychology courses and psychology faculty. Reports that students found more reasons acceptable for missing classes and that the amount of in-class material on the examinations…

  2. 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 is the...... 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 the...

  3. Electroactive mesoporous yttria stabilized zirconia containing platinum or nickel oxide nanoclusters: a new class of solid oxide fuel cell electrode materials

    Energy Technology Data Exchange (ETDEWEB)

    Mamak, M.; Coombs, N.; Ozin, G.A. [Toronto Univ., ON (Canada). Dept. of Chemistry

    2001-02-01

    The electroactivity of surfactant-templated mesoporous yttria stabilized zirconia, containing nanoclusters of platinum or nickel oxide, is explored by alternating current (AC) complex impedance spectroscopy. The observed oxygen ion and mixed oxygen ion-electron charge-transport behavior for these materials, compared to the sintered-densified non-porous crystalline versions, is ascribed to the unique integration of mesoporosity and nanocrystallinity within the binary and ternary solid solution microstructure. These attributes inspire interest in this new class of materials as candidates for the development of improved performance solid oxide fuel cell electrodes. (orig.)

  4. Design and fabrication of a new class of nano hybrid materials based on reactive polymeric molecular cages.

    Science.gov (United States)

    Zhang, De Suo; Liu, Xiang Yang; Li, Jing Liang; Xu, Hong Yao; Lin, Hong; Chen, Yu Yue

    2013-09-10

    This paper describes a strategy of fabricating a new class of nano hybrid particles in terms of the "nanocages" of reactive molecular matrices/networks. The concept is to design molecular matrices functionalized with particular reactive groups, which can on-site synthesize and fix nanoparticles at the designated positions of the molecular networks. The cages of the molecular networks impose the confinement and protection to the nanoparticles so that the size and the stability of nano hybrid particles can be better controlled. To this end, polyamide network polymers (PNP) were synthesized and adopted as the reactive molecular cages for the control of silver nanoparticles formation. It follows that the silver nano hybrid particles fabricated by this method have an average diameter of 4.34 nm much smaller than any other or similar methods ie by a hyperbranched polyamide polymer (HB-PA). As per our design, the size of the silver nano hybrid particles can also be tuned by controlling the molar ratio between silver ions and the functional groups in the polymeric matrices. The silver nano hybrid particles reveal the substantially enhanced stability in aqueous solutions, which gives rise to the long stable performance of localized surface plasmon resonance. As the nano hybrid particles display long eminent nanoeffects, they exert broad implications for a wide range of applications such as biomedicine, catalysis, and optoelectronics. PMID:23980927

  5. theories of class

    Science.gov (United States)

    Gaiotto, Davide; Razamat, Shlomo S.

    2015-07-01

    We construct classes of superconformal theories elements of which are labeled by punctured Riemann surfaces. Degenerations of the surfaces correspond, in some cases, to weak coupling limits. Different classes are labeled by two integers ( N, k). The k = 1 case coincides with A N - 1 theories of class and simple examples of theories with k > 1 are orbifolds of some of the A N - 1 class theories. For the space of theories to be complete in an appropriate sense we find it necessary to conjecture existence of new strongly coupled SCFTs. These SCFTs when coupled to additional matter can be related by dualities to gauge theories. We discuss in detail the A 1 case with k = 2 using the supersymmetric index as our analysis tool. The index of theories in classes with k > 1 can be constructed using eigenfunctions of elliptic quantum mechanical models generalizing the Ruijsenaars-Schneider integrable model. When the elliptic curve of the model degenerates these eigenfunctions become polynomials with coefficients being algebraic expressions in fugacities, generalizing the Macdonald polynomials with rational coefficients appearing when k = 1.

  6. Residues of Chern classes

    OpenAIRE

    Suwa, Tatsuo; 諏訪, 立雄

    2003-01-01

    If we have a finite number of sections of a complex vector bundle E over a manifold M, certain Chern classes of E are localized at the singular set S, i.e., the set of points where the sections fail to be linearly independent. When S is compact, the localizations define the residues at each connected component of S by the Alexander duality. If M itself is compact, the sum of the residues is equal to the Poincaré dual of the corresponding Chern class. This type of theory is also developed for ...

  7. Residues of Chern classes

    OpenAIRE

    Suwa, Tatsuo

    2003-01-01

    If we have a finite number of sections of a complex vector bundle $E$ over a manifold $M$ , certain Chern classes of $E$ are localized at the singular set $S$ , i.e., the set of points where the sections fail to be linearly independent. When $S$ is compact, the localizations define the residues at each connected component of $S$ by the Alexander duality. If $M$ itself is compact, the sum of the residues is equal to the Poincaré dual of the corresponding Chern class. This type of theory is als...

  8. 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…

  9. Class notes from the first international training course on the physical protection of nuclear facilities and materials

    Energy Technology Data Exchange (ETDEWEB)

    Herrington, P.B. (ed.)

    1979-05-01

    The International Training Course on Physical Protection of Nuclear Facilities and Materials was intended for representatives from the developing countries who are responsible for preparing regulations and designing and assessing physical protection systems. The first part of the course consists of lectures on the objectives, organizational characteristics, and licensing and regulations requirements of a state system of physical protection. Since the participants may have little experience in nuclear energy, background information is provided on the topics of nuclear materials, radiation hazards, reactor systems, and reactor operations. Transportation of nuclear materials is addressed and emphasis is placed on regulations. Included in these discussions are presentations by guest speakers from countries outside the United States of America who present their countries' threat to nuclear facilities. Effectiveness evaluation methodology is introduced to the participants by means of instructions which teach them how to use logic trees and the EASI (Estimate of Adversary Sequence Interruption) program. The following elements of a physical protection system are discussed: barriers, protective force, intrusion detection systems, communications, and entry-control systems. Total systems concepts of physical protection system design are emphasized throughout the course. Costs, manpower/technology trade-offs, and other practical considerations are discussed. Approximately one-third of the course is devoted to practical exercises during which the attendees participatein problem solving. A hypothetical nuclear facility is introduced, and the attendees participate in the conceptual design of a physical protection system for the facility.

  10. Class notes from the first international training course on the physical protection of nuclear facilities and materials

    International Nuclear Information System (INIS)

    The International Training Course on Physical Protection of Nuclear Facilities and Materials was intended for representatives from the developing countries who are responsible for preparing regulations and designing and assessing physical protection systems. The first part of the course consists of lectures on the objectives, organizational characteristics, and licensing and regulations requirements of a state system of physical protection. Since the participants may have little experience in nuclear energy, background information is provided on the topics of nuclear materials, radiation hazards, reactor systems, and reactor operations. Transportation of nuclear materials is addressed and emphasis is placed on regulations. Included in these discussions are presentations by guest speakers from countries outside the United States of America who present their countries' threat to nuclear facilities. Effectiveness evaluation methodology is introduced to the participants by means of instructions which teach them how to use logic trees and the EASI (Estimate of Adversary Sequence Interruption) program. The following elements of a physical protection system are discussed: barriers, protective force, intrusion detection systems, communications, and entry-control systems. Total systems concepts of physical protection system design are emphasized throughout the course. Costs, manpower/technology trade-offs, and other practical considerations are discussed. Approximately one-third of the course is devoted to practical exercises during which the attendees participatein problem solving. A hypothetical nuclear facility is introduced, and the attendees participate in the conceptual design of a physical protection system for the facility

  11. 49 CFR 173.428 - Empty Class 7 (radioactive) materials packaging.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Empty Class 7 (radioactive) materials packaging... SHIPPERS-GENERAL REQUIREMENTS FOR SHIPMENTS AND PACKAGINGS Class 7 (Radioactive) Materials § 173.428 Empty Class 7 (radioactive) materials packaging. A packaging which previously contained Class 7...

  12. IRIDIUM LINER FOR NASA 5 LBF CLASS MATERIAL TEST CHAMBER IRIDIUM LINER FOR ATLANTIC RESEARCH CORPORA

    Science.gov (United States)

    1995-01-01

    IRIDIUM LINER FOR NASA 5 LBF CLASS MATERIAL TEST CHAMBER IRIDIUM LINER FOR ATLANTIC RESEARCH CORPORATION 5 LBF CLASS ROCKET CHAMBER 25 LBF CLASS 75 HFC 25 TAC CERAMIC COMPOSITE ROCKET CHAMBER FROM REFRACTURY COMPOSITES INC. PURCHASE ORDER C-551941-

  13. Student Reactions to Materials Relating to the Social Sciences in a Third Semester College Spanish Class.

    Science.gov (United States)

    Stansfield, Charles W.

    The problem of evaluating instructional materials in foreign language courses in terms of educational relevance is examined in this survey of a third-semester, college, Spanish class. Students were given reading materials in the social sciences in lieu of the more traditional literary selections and asked to evaluate them through an attitudinal…

  14. Aviation Structural Mechanic, Second Class, 2-13. Military Curriculum Materials for Vocational and Technical Education.

    Science.gov (United States)

    Ohio State Univ., Columbus. National Center for Research in Vocational Education.

    This self-paced, individualized course, adapted from military curriculum materials for use in vocational and technical education, teaches students the skills needed to become aviation structural mechanics (second class). The course materials consist of five pamphlets covering the structural maintenance and repair of aircraft. The first pamphlet…

  15. Aviation Structural Mechanic, First Class, 2-12. Military Curriculum Materials for Vocational and Technical Education.

    Science.gov (United States)

    Ohio State Univ., Columbus. National Center for Research in Vocational Education.

    This self-paced, individualized course, adapted from military curriculum materials for use in vocational and technical education, teaches students the skills needed to become aviation structural mechanics (first class). The course materials consist of three pamphlets. The first pamphlet covers aircraft maintenance management, records, and reports…

  16. The Class of '34

    OpenAIRE

    Cairney, Richard

    1995-01-01

    The Great Depression raged, governments were beleaguered, the unemployment rate stood at 30%, scurvy stalked the poor and no one was immune to contagious diseases such as scarlet fever, polio and measles when the University of Alberta School of Medicine's Class of '34 graduated. For four alumni who recently gathered in Edmonton—Drs. Morley Hodgson, Melvin Gaudin, John McLurg and Edmund Cairns—their 60th-anniversary reunion was a time to recall the changes they have witnessed in medicine, incl...

  17. New class of photocatalytic materials and a novel principle for efficient water splitting under infrared and visible light: MgB2 as unexpected example.

    Science.gov (United States)

    Kravets, V G; Grigorenko, A N

    2015-11-30

    Water splitting is unanimously recognized as environment friendly, potentially low cost and renewable energy solution based on the future hydrogen economy. Especially appealing is photocatalytic water splitting whereby a suitably chosen catalyst dramatically improves efficiency of the hydrogen production driven by direct sunlight and allows it to happen even at zero driving potential. Here, we suggest a new class of stable photocatalysts and the corresponding principle for catalytic water splitting in which infrared and visible light play the main role in producing the photocurrent and hydrogen. The new class of catalysts - ionic or covalent binary metals with layered graphite-like structures - effectively absorb visible and infrared light facilitating the reaction of water splitting, suppress the inverse reaction of ion recombination by separating ions due to internal electric fields existing near alternating layers, provide the sites for ion trapping of both polarities, and finally deliver the electrons and holes required to generate hydrogen and oxygen gases. As an example, we demonstrate conversion efficiency of ~27% at bias voltage Vbias = 0.5V for magnesium diboride working as a catalyst for photoinduced water splitting. We discuss its advantages over some existing materials and propose the underlying mechanism of photocatalytic water splitting by binary layered metals. PMID:26698811

  18. Evaluation of arch width among Class I normal occlusion, Class II Division 1, Class II Division 2, and Class III malocclusion in Indian population

    OpenAIRE

    Dolly Patel; Falguni Mehta; Nimesh Patel; Nishit Mehta; Ipist Trivedi; Apexa Mehta

    2015-01-01

    Objective: To test the hypothesis that there is no difference between Class I (CI) normal occlusion, Class II division 1 (CIId1) and CII division 2 (CIId2), and Class III (CIII) malocclusion with respect to arch widths, width of the maxillary and mandibular arches, gender dimorphism within groups, and gender comparisons. Materials and Methods: Samples of 40 CI subjects, 40 CIId1 subjects, 40 CIId2 subjects, and 34 CIII subjects were studied. All subjects were Indians with no history of or...

  19. A study of the compatibility of an existing CFD package with a broader class of material constitutions

    Science.gov (United States)

    French, K. W., Jr.

    1985-01-01

    The flexibility of the PHOENICS computational fluid dynamics package was assessed along two general avenues; parallel modeling and analog modeling. In parallel modeling the dependent and independent variables retain their identity within some scaling factors, even though the boundary conditions and especially the constitutive relations do not correspond to any realistic fluid dynamic situation. PHOENICS was used to generate a CFD model that should exhibit the physical anomalies of a granular medium and permit reasonable similarity with boundary conditions typical to membrane or porous piston loading. A considerable portion of the study was spent prying into the existing code with a prejudice toward rate type and disarming any inherent fluid behavior. The final stages of the study were directed at the more specific problem of multiaxis loading of cylindrical geometry with a concern for the appearance of bulging, cross slab shear failure modes.

  20. Metal free earth abundant elemental red phosphorus: a new class of visible light photocatalyst and photoelectrode materials.

    Science.gov (United States)

    Ansari, Sajid Ali; Ansari, Mohammad Shahnawaze; Cho, Moo Hwan

    2016-02-01

    Developing a high-performance photocatalyst and a photoelectrode with enhanced visible light harvesting properties is essential for practical visible light photocatalytic applications. Noble metal-free, highly visible light-active, elemental red phosphorus (RP) was prepared by a facile mechanical ball milling method, which is a reproducible, low cost and controllable synthesis process. The synthesis used inexpensive and abundant raw materials because most RP hybrids are based on expensive noble-metals. The novel milled RP showed significantly enhanced photocatalytic and photoelectrochemical performances with a lower charge transfer resistance compared to commercial RP under wide visible photoirradiation, making it a feasible alternative for photocatalytic applications. PMID:26765211

  1. A New Class of Octahedral Molecular Sieve Materials for the Selective Removal and Sequestration of 90Sr2+

    International Nuclear Information System (INIS)

    The structure of Na16Nb12.8Ti3.2O44.8(OH)3.2 · 8H2O, a member of a new family of Sandia Octahedral Molecular Sieves (SOMS) having a Nb/Na/MIV (M= Ti, Zr) oxide framework and exchangeable Na and water in open channels, was determined from Synchrotron X-ray data. The SOMS phases are isostructural with variable MIV:Nb(1:50--1:4) ratios. The SOMS are extremely selective for sorption of divalent cations, particularly Sr2+. The ion-exchanged SOMS undergo direct thermal conversion to a perovskite-type phase, indicating this is a promising new method for removal and sequestration of radioactive Sr-90 from mixed nuclear wastes

  2. Raradox of class description

    Institute of Scientific and Technical Information of China (English)

    吕光

    2004-01-01

    We have a more active class atmophere, but more passive self-study situations. We are too talktive when we should bury ourselves in books, but too less efficient when we spend too much time. We complain teachers

  3. Use of a Concentration Game for Environmental Chemistry Class Review

    Science.gov (United States)

    Nowosielski, Danica A.

    2007-01-01

    The concentration game can be used as a complete class or a portion of it to help reinforce the material being presented or for review sessions. An environmental chemistry class review is presented with the use of the concentration game.

  4. A robust, melting class bulk superhydrophobic material with heat-healing and self-cleaning properties

    OpenAIRE

    Ramakrishna, S; Santhosh Kumar, K. S.; Dona Mathew; Reghunadhan Nair, C. P.

    2015-01-01

    Superhydrophobic (SH) materials are essential for a myriad of applications such as anti-icing and self-cleaning due to their extreme water repellency. A single, robust material simultaneously possessing melt-coatability, bulk water repellency, self-cleanability, self-healability, self-refreshability, and adhesiveness has been remaining an elusive goal. We demonstrate a unique class of melt-processable, bulk SH coating by grafting long alkyl chains on silica nanoparticle surface by a facile on...

  5. Computational Nano-materials Design for Spinodal Nanotechnology as a New Class of Bottom-up Nanotechnology

    Science.gov (United States)

    Katayama-Yoshida, Hiroshi; Fukushima, Tetsuya; Sato, Kazunori

    Based on the spinodal nano-decomposition (SND) of dilute magnetic semiconductors (DMS), we generalized the SND to the application of catalysis and photovoltaic solar-cells, where nano-scale particle formation in catalysis and and nano-scale separation of electrons and holes are essential in order to enhance the efficiency. First, we summarize the shape control (Konbu- & Dairiseki-Phases) and dimensionality dependence of crystal growth condition on SND in DMS. Second, we discuss the application of SND for the formation of nano-particles and the self-regeneration in three-way catalysis for automotive emission control by Perovskite La(Fe,Pd or Rh)O3. Third, we propose (i) self-regeneration mechanism and (ii) self-organized nano-structures by SND in chalcopyrite Cu(In,Ga)Se2, Kesterite Cu2ZnSnSe4, and Perovskite CsSnI3 for the low-cost, environment-friendly and high-efficiency photovoltaic solar cells using first-principles calculations.

  6. Teachers' professional growth during the development and class enactment of context-based chemistry student learning material

    NARCIS (Netherlands)

    Coenders, Fer

    2010-01-01

    In 2002, a committee installed by the Ministry of Education concluded that four main problems regarding the high school chemistry curriculum necessitate a major curriculum renewal. A year later the following three recommendations for such a new curriculum were formulated: (a) the chemistry content s

  7. New class of neutron detectors

    Energy Technology Data Exchange (ETDEWEB)

    Czirr, J.B.

    1997-09-01

    An optimized neutron scattering instrument design must include all significant components, including the detector. For example, useful beam intensity is limited by detector dead time; detector pixel size determines the optimum beam diameter, sample size, and sample to detector distance; and detector efficiency vs. wavelength determines the available energy range. As an example of the next generation of detectors that could affect overall instrumentation design, we will describe a new scintillator material that is potentially superior to currently available scintillators. We have grown and tested several small, single crystal scintillators based upon the general class of cerium-activated lithium lanthanide borates. The outstanding characteristic of these materials is the high scintillation efficiency-as much as five times that of Li-glass scintillators. This increase in light output permits the practical use of the exothermic B (n, alpha) reaction for low energy neutron detection. This reaction provides a four-fold increase in capture cross section relative to the Li (n, alpha) reaction, and the intriguing possibility of demanding a charged-particle/gamma ray coincidence to reduce background detection rates. These new materials will be useful in the thermal and epithermal energy ran at reactors and pulsed neutron sources.

  8. A Touch of...Class!

    Science.gov (United States)

    Netten, Joan W., Ed.

    1984-01-01

    A collection of ideas for class activities in elementary and secondary language classes includes a vocabulary review exercise and games of memory, counting, vocabulary, flashcard tic-tac-toe, dice, trashcans, questioning, and spelling. Some are designed specifically for French. (MSE)

  9. The Generalizability of Class Means

    Science.gov (United States)

    Kane, Michael T.; Brennan, Robert L.

    1977-01-01

    Dependability of class means is analyzed by applying generalizability to a split-plot design with students nested within classes. Basic generalizability concepts are reviewed, and the derivation and interpretation of distinct generalizability concepts are discussed. Four generalizability coefficients are compared with each other and with the three…

  10. Application of the Materials-by-Design Methodology to Redesign a New Grade of the High-Strength Low-Alloy Class of Steels with Improved Mechanical Properties and Processability

    Science.gov (United States)

    Grujicic, M.; Snipes, J. S.; Ramaswami, S.

    2016-01-01

    An alternative to the traditional trial-and-error empirical approach for the development of new materials is the so-called materials-by-design approach. Within the latter approach, a material is treated as a complex system and its design and optimization is carried out by employing computer-aided engineering analyses, predictive tools, and available material databases. In the present work, the materials-by-design approach is utilized to redesign a grade of high-strength low-alloy (HSLA) class of steels with improved mechanical properties (primarily strength and fracture toughness), processability (e.g., castability, hot formability, and weldability), and corrosion resistance. Toward that end, a number of material thermodynamics, kinetics of phase transformations, and physics of deformation and fracture computational models and databases have been developed/assembled and utilized within a multi-disciplinary, two-level material-by-design optimization scheme. To validate the models, their prediction is compared against the experimental results for the related steel HSLA100. Then the optimization procedure is employed to determine the optimal chemical composition and the tempering schedule for a newly designed grade of the HSLA class of steels with enhanced mechanical properties, processability, and corrosion resistance.

  11. A Survey of English Reading Outside Class

    Institute of Scientific and Technical Information of China (English)

    Peng; Yuan

    2015-01-01

    The aims of middle school English teaching areto cultivate students to acquire reading competence,which enable them to gain the information.Reading is the required method to collect information and material.This paper reports a survey on reading outside class among senior school students,by the way of questionnaires and interview,including the interests,focus,assignment of reading time,selection of reading materials,reading motives and other aspects..

  12. A Survey of English Reading Outside Class

    Institute of Scientific and Technical Information of China (English)

    Peng Yuan

    2015-01-01

    The aims of middle school English teaching are to cultivate students to acquire reading competence,which enable them to gain the information.Reading is the required method to collect information and material.This paper reports a survey on reading outside class among senior school students,by the way of questionnaires and interview,including the interests,focus,assignment of reading time,selection of reading materials,reading motives and other aspects..

  13. Class in Metropolitan India: The Rise of the Middle Classes

    OpenAIRE

    Mooij, Jos; Lama-Rewal, S.T.

    2009-01-01

    textabstractIt is almost a cliché to say that India’s appearance and image (internationally as well as self-image) have changed dramatically in the last fifteen years. Instead of being associated with rural poverty, India is now associated with high rates of economic growth, a booming Information Technology (IT) sector and, particularly, an increasingly expanding middle class that consumes and behaves like elites and middle classes elsewhere in the world. Considering that cities concentrate m...

  14. A new class of photo-catalytic materials and a novel principle for efficient water splitting under infrared and visible light - MgB2 as unexpected example

    CERN Document Server

    Kravets, V G

    2015-01-01

    Water splitting is unanimously recognized as environment friendly, potentially low cost and renewable energy solution based on the future hydrogen economy. Especially appealing is photo-catalytic water splitting whereby a suitably chosen catalyst dramatically improves efficiency of the hydrogen production driven by direct sunlight and allows it to happen even at zero driving potential. Here, we suggest a new class of stable photo-catalysts and the corresponding principle for catalytic water splitting in which infrared and visible light play the main role in producing the photocurrent and hydrogen. The new class of catalysts based on ionic binary metals with layered graphite-like structures which effectively absorb visible and infrared light facilitating the reaction of water splitting, suppress the inverse reaction of ion recombination by separating ions due to internal electric fields existing near alternating layers, provide the sites for ion trapping of both polarities, and finally deliver the electrons an...

  15. A new class of sonic composites

    Science.gov (United States)

    Munteanu, Ligia; Chiroiu, Veturia; Donescu, Ştefania; Brişan, Cornel

    2014-03-01

    Transformation acoustics opens a new avenue towards the architecture, modeling and simulation of a new class of sonic composites with scatterers made of various materials and having various shapes embedded in an epoxy matrix. The design of acoustic scatterers is based on the property of Helmholtz equations to be invariant under a coordinate transformation, i.e., a specific spatial compression is equivalent to a new material in a new space. In this paper, the noise suppression for a wide full band-gap of frequencies is discussed for spherical shell scatterers made of auxetic materials (materials with negative Poisson's ratio). The original domain consists of spheres made from conventional foams with positive Poisson's ratio. The spatial compression is controlled by the coordinate transformation, and leads to an equivalent domain filled with an auxetic material. The coordinate transformation is strongly supported by the manufacturing of auxetics which is based on the pore size reduction through radial compression molds.

  16. CaTiO.sub.3 Interfacial template structure on semiconductor-based material and the growth of electroceramic thin-films in the perovskite class

    Science.gov (United States)

    McKee, Rodney Allen; Walker, Frederick Joseph

    1998-01-01

    A structure including a film of a desired perovskite oxide which overlies and is fully commensurate with the material surface of a semiconductor-based substrate and an associated process for constructing the structure involves the build up of an interfacial template film of perovskite between the material surface and the desired perovskite film. The lattice parameters of the material surface and the perovskite of the template film are taken into account so that during the growth of the perovskite template film upon the material surface, the orientation of the perovskite of the template is rotated 45.degree. with respect to the orientation of the underlying material surface and thereby effects a transition in the lattice structure from fcc (of the semiconductor-based material) to the simple cubic lattice structure of perovskite while the fully commensurate periodicity between the perovskite template film and the underlying material surface is maintained. The film-growth techniques of the invention can be used to fabricate solid state electrical components wherein a perovskite film is built up upon a semiconductor-based material and the perovskite film is adapted to exhibit ferroelectric, piezoelectric, pyroelectric, electro-optic or large dielectric properties during use of the component.

  17. Spectroscopic characterization of various Yb.sup.3+./sup. doped laser materials at cryogenic temperatures for the development of high energy class diode pumped solid state lasers

    Czech Academy of Sciences Publication Activity Database

    Jambunathan, Venkatesan; Koerner, J.; Sikocinski, Pawel; Divoký, Martin; Sawicka, Magdalena; Lucianetti, Antonio; Hein, J.; Mocek, Tomáš

    Bellingham: SPIE, 2013 - (Hein, J.; Korn, G.; Silva, L.), 87800G. (Proceedings of SPIE. 8780). ISBN 978-0-8194-9582-2. ISSN 0277-786X. [High-Power, High-Energy, and High-Intensity Laser Technology; and Research Using Extreme Light - Entering New Frontiers with Petawatt-Class Lasers. Praha (CZ), 15.04.2013-17.04.2013] Institutional support: RVO:68378271 Keywords : YAG * LuAG * CaF2 * FP15-glass * cross-section Subject RIV: BH - Optics, Masers, Lasers

  18. A library of function classes

    International Nuclear Information System (INIS)

    We have written a library of function classes in C++, which is distributed as part of the CLHEP foundation class libraries for High Energy Physics. The main goals of the library are to provide objects having all the mathematical behavior of functions, and to provide a mechanism for parameterizing these functions. Our functions support all the normal function operations such as addition, subtraction, multiplication, division, composition, et. cetera. The library allows programmers to compose complicated one-or multi-dimensional functions with great economy and natural semantics

  19. Lateral cephalometric diagnosis of asymmetry in Angle Class II subdivision compared to Class I and II

    OpenAIRE

    Aparecida Fernanda Meloti; Renata de Cássia Gonçalves; Ertty Silva; Lídia Parsekian Martins; Ary dos Santos-Pinto

    2014-01-01

    INTRODUCTION: Lateral cephalometric radiographs are traditionally required for orthodontic treatment, yet rarely used to assess asymmetries. OBJECTIVE: The objective of the present study was to use lateral cephalometric radiographs to identify existing skeletal and dentoalveolar morphological alterations in Class II subdivision and to compare them with the existing morphology in Class I and II relationship. MATERIAL AND METHODS: Ninety initial lateral cephalometric radiographs of male...

  20. On uniqueness of characteristic classes

    DEFF Research Database (Denmark)

    Feliu, Elisenda

    2011-01-01

    We give an axiomatic characterization of maps from algebraic K-theory. The results apply to a large class of maps from algebraic K-theory to any suitable cohomology theory or to algebraic K-theory. In particular, we obtain comparison theorems for the Chern character and Chern classes and for the...... Adams operations and ¿-operations on higher algebraic K-theory. We show that the Adams operations and ¿-operations defined by Grayson agree with the ones defined by Gillet and Soulé....

  1. A Class of Graceful Trees

    Institute of Scientific and Technical Information of China (English)

    孟凡洪; 苏耕; 杨继

    2000-01-01

    The present paper shows the coordinates of a tree and its vertices, defines a kind of Trees with Odd-Number Radiant Type (TONRT), deals with the gracefulness of TONRT by using the edge-moving theorem, and uses graceful TONRT to construct another class of graceful trees.

  2. Design of Class-E Radio Frequency Power Amplifier

    OpenAIRE

    Al-Shahrani, Saad Mohammed

    2000-01-01

    Power amplifiers (PA) are typically the most power-consuming building blocks of RF transceivers. Therefore, the design of a high-efficiency radio frequency power amplifier is the most obvious solution to overcoming the battery lifetime limitation in the portable communication systems. A power amplifierà ­s classes (A, AB, B, C, F, E, etc), and design techniques (Load-pull and large-signal S-parameters techniques) are presented. The design accuracy of class-A power amplifier based on the s...

  3. Art of Class Teaching Encourage

    Institute of Scientific and Technical Information of China (English)

    HE Jiao-fei

    2013-01-01

    Teaching encourage can lead to student’s learning motivation and interesting. It improves the effect of classroom teach⁃ing. Methods of class teaching inspiration are: Target encourage, expectation encourage, emotional encourage, positive encourage, attribution encourage, competition encourage, caress encourage, democracy encourage, praise encourage, time encourage, check en⁃courage, questions encourage, examination encourage, score encourage, example encourage and understanding encourage.

  4. DNA as Genetic Material: Revisiting Classical Experiments through an Easy, Practical Class

    Directory of Open Access Journals (Sweden)

    W. J. Malagó

    2009-05-01

    Full Text Available In 1928, Frederick Griffith demonstrated a process of transmission of genetic information by transforming  Pneumococcus. In 1944, Oswald Avery, Colin Munro MacLeod and Maclyn McCarty showed that Griffith´stransformation principle  is DNA. Here, we intend to revisit these classicalexperiments by reproducing them in easier adapted forms, for a practical class given to undergraduate students. The Griffith experiment was reproduced by mixing heat-killed, ampicillin - resistant  E. coliwith live ampicillin -susceptible  E. coli, followed by plating samples in the presence or absence of the antibiotic. Cells were also plated separately as control. Avery’s work was reproduced by pre-treating a purified plasmid harboring the ampicillin resistan ce gene with Dnase I. Treated and untreated plasmids were then used to transform  E. colicells, which were plated in culture media containing ampicillin. The students received a class guide with brief theoretical explanations and protocols to perform the experiments. The original papers by Griffith and Avery  et al. were also provided, along with a list of questions to encourage a discussion on the experimental approach and results obtained. The adapted experiments were successful completed and all expected results were obtained in class. Thus the students effectively revisited the classical experiments which revealed that DNA is the genetic material. Also, the class was very well accepted, as indicated by students’ evaluations. Thus, we presented an inexpens ive, quick class involving important concepts, which can be easily reproduced in any laboratory withminor resources.

  5. Special Classes of Solutions for Linear String Baryon Configuration

    OpenAIRE

    Petrov, V. P.; Sharov, G. S.

    2001-01-01

    For the linear string baryon model with three material points (three quarks) joined sequentially by the relativistic strings, the class of motions admitting linearizable boundary conditions is investigated. These motions may be represented as the Fourier series with eigenfunctions of some boundary-value problem. The two types of rotational motions are found among the mentioned class of solutions.

  6. Stochastic prediction of drought class transitions

    OpenAIRE

    Paulo, Ana A.; L. S. Pereira

    2008-01-01

    This paper aims at the stochastic characterization of droughts applying Markov chains modeling to drought class transitions derived from SPI time series. Several sites in Southern Portugal having updated data on precipitation available were considered. The drought class probabilities, the expected residence time in each class of severity, the expected time for the transition between drought classes and the drought severity class predictions 1, 2, or 3 months ahead have been obt...

  7. Safety-technical lay-out of the operational environment of a high-power spallation target system of the megawatt class with mercury as target material

    International Nuclear Information System (INIS)

    This thesis is concerning the safety relevant layout of the environment of a mercury based 5-Megawatt-spallation target. All safety relevant aspects related to construction, operation and dismantling as well as economical issues were taken into account. Safety concerns are basically driven by the toxic and radioactive inventory as well as the kind and intensity of radiation produced by the spallation process. Due to significant differences in inventory and radiation between a spallation source and a fission reactor, for the design of the spallation source mentioned above the safety philosophy of a fission reactor must not be used unchanged. Rather than this a systematic study of all safety related boundary conditions is necessary. Within this thesis all safety relevant boundary conditions for this specific type of machine are given. Beside the spatial distribution of different areas inside the target station, influence of medias to be used as well as arising radiation and handling requirements are discussed in detail. A general layout of the target station is presented, serving as a basis for all further component and system development. An enclosure concept for the target station was developed, taking into account the safety relevant issues concerning the mercury used as target materials, the water cooling loops containing massive amounts of tritium as well as the materials used for the moderators potentially forming explosive mixtures. Concept and detailed technical layout of the enclosure system was chosen to guarantee safe operation of the source as well as taking care of requirement arising for handling needs. For design of the shielding different suitable materials have been discussed. A design for assembling the shielding is shown taking into account the safety relevant requirements during operation as well as during dismantling. The neutron beam shutters, buried inside the shielding were designed to optimize handling and positioning issued of the inner part

  8. Multimedia Material to Help Photosynthesis Teaching in Regular and Distance Classes

    Directory of Open Access Journals (Sweden)

    G.R.T. Costa

    2005-07-01

    Full Text Available The  difficulties  related  to  the  understanding of biochemistry  concepts  and  processes  observed during  regular  classes using  only schemes  and  static  pictures  have  raised  the  interest of professors towards  multimedia material.   In  the  few last  decades  we could  notice the  development of many computational tools that are helping this  process.  This  work presents a software  elaborated to show the  phases  of Photosynthesis (both  light-dependent  and  independent  processes.   FLASH  software was used to  make  regular  classes more attractive with schemes,  interactivity and  animations to  be projected.   An intuitive navigation system  was elaborated using ActionScript programming, so that students can  use the  same class material  for reviewing the major  topics.   The  students will benefit from characteristics like text boxes, summarizing  the  concepts  displayed  on each screen,  the  guided study  mode that suggests to the student the next  navigation step and the automatic navigation that gives a general look about the theme,  yet keeping the freedom for choosing any available  topic.

  9. 49 CFR 172.403 - Class 7 (radioactive) material.

    Science.gov (United States)

    2010-10-01

    ... for the package design issued by the Competent Authority for import and export shipments. For... definition for “transport index,” taken by the person initially offering the packages contained within the... Register citations affecting § 172.403, see the List of CFR Sections Affected which appears in the...

  10. 49 CFR 173.116 - Class 2-Assignment of hazard zone.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Class 2-Assignment of hazard zone. 173.116 Section... for Hazardous Materials Other Than Class 1 and Class 7 § 173.116 Class 2—Assignment of hazard zone. (a) The hazard zone of a Class 2, Division 2.3 material is assigned in column 7 of the § 172.101...

  11. TEACHING "CORROSION AND CORROSION-RESISTANT MATERIALS" CLASS AS A MUST COURSE IN MATERIAL AND MATERIAL PROCESSING TECHNOLOGIES PROGRAM

    OpenAIRE

    GERENGİ, Hüsnü; KURTAY, Mine

    2013-01-01

    Corrosion has become a main problem due to the rise in the use of metal with the developing technology. Corrosion is the degradation of metal or metal alloys as a result of chemical or electrochemical reactions. Corrosion education is a matter of concern for all material types. The aim of this study is to demonstrate and discuss the importance of “Corrosion and Corrosion Materials Technology Course” indicating the importance of corrosion science and taught in all programs under the Department...

  12. A class of integrable metrics

    Science.gov (United States)

    Anabalón, Andrés; Batista, Carlos

    2016-03-01

    In four dimensions, the most general metric admitting two commuting Killing vectors and a rank-two Killing tensor can be parametrized by ten arbitrary functions of a single variable. We show that picking a special vierbein, reducing the system to eight functions, implies the existence of two geodesic and share-free, null congruences, generated by two principal null directions of the Weyl tensor. Thus, if the spacetime is an Einstein manifold, the Goldberg-Sachs theorem implies it is Petrov type D, and by explicit construction, is in the Carter class. Hence, our analysis provides a straightforward connection between the most general integrable structure and the Carter family of spacetimes.

  13. A Class of Integrable Metrics

    CERN Document Server

    Anabalon, Andres

    2016-01-01

    In four dimensions, the most general metric admitting two Killing vectors and a rank-two Killing tensor can be parameterized by ten arbitrary functions of a single variable. We show that picking a special vierbien, reducing the system to eight functions, implies the existence of two geodesic and share-free, null congruences, generated by two principal null directions of the Weyl tensor. Thus, if the spacetime is an Einstein manifold, the Goldberg-Sachs theorem implies it is Petrov type D, and by explicit construction, is in the Carter class. Hence, our analysis provide an straightforward connection between the most general integrable structure and the Carter family of spacetimes.

  14. A Class of DSm Conditional Rules

    OpenAIRE

    Smarandache, Florentin; Alford, Mark

    2009-01-01

    In this paper we introduce two new DSm fusion conditioning rules with example, and as a generalization of them a class of DSm fusion conditioning rules, and then extend them to a class of DSm conditioning rules.

  15. Characteristic classes of mixed Hodge modules

    CERN Document Server

    Schuermann, Joerg

    2009-01-01

    This paper gives an introduction and overview about recent developments on the interaction of the theories of characteristic classes and mixed Hodge theory for singular spaces in the complex algebraic context. It uses M. Saito's deep theory of mixed Hodge modules as a "black box", thinking about them as "constructible or perverse sheaves of Hodge structures", having the same functorial calculus of Grothendieck functors. For the "constant Hodge sheaf", one gets the "motivic characteristic classes" of Brasselet-Schuermann-Yokura, whereas the classes of the "intersection homology Hodge sheaf" were studied by Cappell-Maxim-Shaneson. There are two versions of these characteristic classes. The K-theoretical classes capture information about the graded pieces of the filtered de Rham complex of the filtered D-module underlying a mixed Hodge module. Application of a suitable Todd class transformation then gives classes in homology. These classes are functorial for proper pushdown and exterior products, together with s...

  16. Diffusion of Responsibility in College Classes

    Institute of Scientific and Technical Information of China (English)

    李珍珍

    2015-01-01

    Diffusion of responsibility takes place in college classes nowadays.The author points out diffusion of responsibility in college classes,analyses psychological reasons of diffusion of responsibility,and gives strategies on avoiding the diffusion of responsibility.The paper aims at doing some contribution to improving teaching quality of college class.

  17. FDA Bolsters Warnings about Class of Antibiotics

    Science.gov (United States)

    ... html FDA Bolsters Warnings About Class of Antibiotics Fluoroquinolones such as Cipro, Levaquin should be reserved for ... label warnings on a class of antibiotics called fluoroquinolones because the drugs can lead to disabling side ...

  18. The Materiality of Learning

    DEFF Research Database (Denmark)

    Sørensen, Estrid

    . Drawing on science and technology studies (STS), Estrid Sørensen compares an Internet-based 3D virtual environment project in a fourth-grade class with the class's work with traditional learning materials, including blackboards, textbooks, notebooks, pencils, and rulers. Taking into account pupils' and...... postgraduate students interested in a variety of fields, including educational studies, educational psychology, social anthropology, and STS. Original ethnographic descriptions showing the fine details of how materials influence the learning process Introduces the advanced and complex Actor-Network Theory to...

  19. New Curricular Material for Science Classes: How Do Students Evaluate It?

    Science.gov (United States)

    Freire, Sofia; Faria, Cláudia; Galvão, Cecília; Reis, Pedro

    2013-02-01

    Living in an unpredictable and ever changing society demands from its' citizens the development of complex competencies that challenges school, education and curriculum. PARSEL, a pan-European Project related to science education, emerges as a contribution to curricular development as it proposes a set of teaching-learning materials (modules) in order to make science classes more popular and relevant in the eyes of the students and as such to increase their interest with school science. The goal of this study was to understand how students evaluate those innovative modules. This paper presents data concerning 134 secondary students, collected through interviews, questionnaires and written documents. A quantitative analysis of the data collected through questionnaires was complemented by a qualitative analysis of the data collected by interviews and written documents. Results show that understanding the relationship between science and daily life, participating in practical activities based on problem solving and developing critical thinking and reasoning were the issues most valued by students.

  20. The Use of Virtual Media Laboratory to Increase Students’ Motivation on Direct Current Circuits Materials at Class X of MAN I Pekanbaru

    Directory of Open Access Journals (Sweden)

    Emhadelima Emhadelima

    2015-12-01

    Full Text Available The purpose of the study is to determine whether there is a significance effect on the use of Practicum methods by using Crocodile Program combined with lectures, question and answer activities give significant effect on  students’ activities in learning electricity simple lesson and to identify whether the use of the simulation lab provides better results than the traditional lab on learning outcomes. 36 natural science students was involved in the study. The data was analyzed by using t-test. The finding showed that the use of Practicum methods by using Crocodile Program combined with lectures; question and answer activities give significant effect on students’ activities in learning electricity simple lesson. The finding also showed that the use of the simulation lab can provide better results than the traditional lab on learning outcomes. It occurred when there is an adequate software capability and students can operate the software properly. Without taking into account about the cost of procurement of computers and software programs Crocodile, lab simulations are very low cost because it does not need to purchase laboratory equipment, supplies and other consumables. It is expected that Crocodile Program not only as a practical method to implement but also as a medium to explain the concepts of electronic circuits. Key words: Virtual Media, Circuits Materials.Copyright © 2015 by Al-Ta'lim All right reserved

  1. Activating Students' Motivation in Speaking in English for Tourism Class by Using Authentic Materials and Tasks

    Institute of Scientific and Technical Information of China (English)

    侯志燕

    2008-01-01

    The author analyzes the existing problems in English for Tourism class and possible reasons why students are not highly motivated in oral communication practice:unconsciousness of the ongoing changing tourism industry, failure in their past learning, fear of losing faces,lack of words, structures and cultural background etc.Aiming to change the present situation and stimulate students'motivation in speaking, she offers some possible ways tO the problems based on her perspectives:(1)choose authenfic materials relevant to student's future career,(2)adapt a more current coulee book which is more authentically tourist-based in content.(3)adapt authentic video and TV tourist based materials related to the experience of tourism.(4)adapt authentic materials to make it more accessible and comprehemible by adaing some proper authendc materiaIs from difierent sources and tasks.(5)organize tearm activities based on authentic situations without changing the dialogue format in order to maintain redundancy of communication but in a real life focus.

  2. Application of Class Activities in English Teaching

    Institute of Scientific and Technical Information of China (English)

    刘琦

    2015-01-01

    Beginning with the analysis of present English teaching,the article puts forward some questions occurring in English classes.Then it talks about the necessity of implementing class activities.Finally it further elaborates how to carry out class activities through three specific examples.

  3. What Are Lay Theories of Social Class?

    OpenAIRE

    Varnum, Michael E. W.

    2013-01-01

    Numerous studies have documented the effects of social class on psychological and behavioral variables. However, lay beliefs about how social class affects these dimensions have not been systematically tested. Studies 1 and 2 assessed lay beliefs about the association between social class and 8 variables (including psychological and behavioral tendencies and cognitive ability). Study 3 assessed lay beliefs about the Big five personality traits and social class, and study 4 reframed the 8 vari...

  4. The Social Psychology of Class and Classism

    Science.gov (United States)

    Lott, Bernice

    2012-01-01

    In the United States, one is born into a family that can be identified as working class, middle class, or affluent--divisions that denote status and power, as defined by access to resources. This article explores the relationships between social class membership and a wide array of personal and social daily life experiences. It concludes with a…

  5. Algebraic Structures using Natural Class of Intervals

    CERN Document Server

    Kandasamy, W B Vasantha

    2011-01-01

    This book has eleven chapters. Chapter one describes all types of natural class of intervals and the arithmetic operations on them. Chapter two introduces the semigroup of natural class of intervals using R or Zn and study the properties associated with them. Chapter three studies the notion of rings constructed using the natural class of intervals. Matrix theory using the special class of intervals is analyzed in chapter four of this book. Chapter five deals with polynomials using interval coefficients. New types of rings of natural intervals are introduced and studied in chapter six. The notion of vector space using natural class of intervals is built in chapter seven. In chapter eight fuzzy natural class of intervals are introduced and algebraic structures on them is built and described. Algebraic structures using natural class of neutrosophic intervals are developed in chapter nine.Chapter ten suggests some possible applications. The final chapter proposes over 200 problems of which some are at research l...

  6. Long-term effects of class size

    OpenAIRE

    Fredriksson, Peter; Öckert, Björn; Oosterbeek, Hessel

    2012-01-01

    This paper evaluates the long-term effects of class size in primary school. We use rich data from Sweden and exploit variation in class size created by a maximum class size rule. Smaller classes in the last three years of primary school (age 10 to 13) are beneficial for cognitive and non-cognitive ability at age 13, and improve achievement at age 16. Most importantly, we find that smaller classes have positive effects on completed education, wages, and earnings at age 27 to 42. The estimated ...

  7. Lateral cephalometric diagnosis of asymmetry in Angle Class II subdivision compared to Class I and II

    Directory of Open Access Journals (Sweden)

    Aparecida Fernanda Meloti

    2014-08-01

    Full Text Available INTRODUCTION: Lateral cephalometric radiographs are traditionally required for orthodontic treatment, yet rarely used to assess asymmetries. OBJECTIVE: The objective of the present study was to use lateral cephalometric radiographs to identify existing skeletal and dentoalveolar morphological alterations in Class II subdivision and to compare them with the existing morphology in Class I and II relationship. MATERIAL AND METHODS: Ninety initial lateral cephalometric radiographs of male and female Brazilian children aged between 12 to 15 years old were randomly and proportionally divided into three groups: Group 1 (Class I, Group 2 (Class II and Group 3 (Class II subdivision. Analysis of lateral cephalometric radiographs included angular measurements, horizontal linear measurements and two indexes of asymmetry that were prepared for this study. RESULTS: In accordance with an Index of Dental Asymmetry (IDA, greater mandibular dental asymmetry was identified in Group 3. An Index of Mandibular Asymmetry (IMA revealed less skeletal and dental mandibular asymmetry in Group 2, greater skeletal mandibular asymmetry in Group 1, and greater mandibular dental asymmetry in Group 3. CONCLUSION: Both IDA and IMA revealed greater mandibular dental asymmetry for Group 3 in comparison to Groups 1 and 2. These results are in accordance with those found by other diagnostic methods, showing that lateral cephalometric radiography is an acceptable method to identify existing skeletal and dentoalveolar morphological alterations in malocclusions.

  8. Integrals of the Ising Class

    Energy Technology Data Exchange (ETDEWEB)

    Bailey, David H.; Borwein, Jonathan M.; Crandall, Richard E.

    2006-06-01

    From an experimental-mathematical perspective we analyze"Ising-class" integrals. Our experimental results involvedextreme-precision, multidimensional quadrature on intricate integrands;thus, highly parallel computation was required.

  9. A robust, melting class bulk superhydrophobic material with heat-healing and self-cleaning properties

    Science.gov (United States)

    Ramakrishna, S.; Santhosh Kumar, K. S.; Mathew, Dona; Reghunadhan Nair, C. P.

    2015-12-01

    Superhydrophobic (SH) materials are essential for a myriad of applications such as anti-icing and self-cleaning due to their extreme water repellency. A single, robust material simultaneously possessing melt-coatability, bulk water repellency, self-cleanability, self-healability, self-refreshability, and adhesiveness has been remaining an elusive goal. We demonstrate a unique class of melt-processable, bulk SH coating by grafting long alkyl chains on silica nanoparticle surface by a facile one-step method. The well-defined nanomaterial shows SH property in the bulk and is found to heal macro-cracks on gentle heating. It retains wettability characteristics even after abrading with a sand paper. The surface regenerates SH features (due to reversible self-assembly of nano structures) quickly at ambient temperature even after cyclic water impalement, boiling water treatment and multiple finger rubbing tests. It exhibits self-cleaning properties on both fresh and cut surfaces. This kind of coating, hitherto undisclosed, is expected to be a breakthrough in the field of melt-processable SH coatings.

  10. A robust, melting class bulk superhydrophobic material with heat-healing and self-cleaning properties

    Science.gov (United States)

    Ramakrishna, S.; Santhosh Kumar, K. S.; Mathew, Dona; Reghunadhan Nair, C. P.

    2015-01-01

    Superhydrophobic (SH) materials are essential for a myriad of applications such as anti-icing and self-cleaning due to their extreme water repellency. A single, robust material simultaneously possessing melt-coatability, bulk water repellency, self-cleanability, self-healability, self-refreshability, and adhesiveness has been remaining an elusive goal. We demonstrate a unique class of melt-processable, bulk SH coating by grafting long alkyl chains on silica nanoparticle surface by a facile one-step method. The well-defined nanomaterial shows SH property in the bulk and is found to heal macro-cracks on gentle heating. It retains wettability characteristics even after abrading with a sand paper. The surface regenerates SH features (due to reversible self-assembly of nano structures) quickly at ambient temperature even after cyclic water impalement, boiling water treatment and multiple finger rubbing tests. It exhibits self-cleaning properties on both fresh and cut surfaces. This kind of coating, hitherto undisclosed, is expected to be a breakthrough in the field of melt-processable SH coatings. PMID:26679096

  11. Flexible Use of Teaching Materials, Excellent Interpret the Class%灵活运用教材,演绎课堂精彩

    Institute of Scientific and Technical Information of China (English)

    李艳静

    2016-01-01

    思想品德课教材是品德教师进行教学的依据和根本。一堂思想品德课的成功与否的关键就在于教师对教材的挖掘和处理是否得当。教师只有吃透教材,在实际的教学实践中使“教材为我所用”,而不可千人一面,照本宣科,导致“我为教材所缚”,本文就灵活使用教材方面谈几点建议。%Text book is the basis for Ideology and morality course teaching. The key of a successful Ideological and moral lesson lies in the teacher's proper mining and processing of text book. The teachers should master the materials thoroughly, and utilize text book fully in real teaching rather than echo what the books say or limited by text book. This paper provides several suggestions on how to use text book flexibly.

  12. Optimization of class 2 tensegrity towers

    Science.gov (United States)

    Masic, Milenko; Skelton, Robert E.

    2004-07-01

    This paper concerns the optimal mass-to-stiffness ratio design of class-2 tensegrity towers. For different loading scenarios, the procedure seeks the topology and geometry of the structure that yields an optimal design satisfying common constraints. The domain of feasible tensegrity geometries is defined by imposing tensegrity equilibrium conditions on both unloaded and loaded structure. Remaining constraints include strength constraints for all elements of the structure and buckling constraints for bars. The symmetry of the design is imposed by restricting the domain of geometric variables and element parameters. The static response of the structure is computed by using a nonlinear large displacement model. The problem is cast in the form of a nonlinear program. The influence of material parameters on the optimal shape of the structure is investigated.

  13. Consumer behavior of the middle class

    OpenAIRE

    Kostyuk, Oleh

    2013-01-01

    The topic of my bachelor thesis is consumer behavior and social stratification. The thesis specifically focuses on the middle class. The aim is to find the differences in the consumer behavior of the middle class and to compare it with other classes. The theoretical part is divided into two parts . The first one is dedicated to consumer behavior, models of explication of this behavior and consumer dispositions. The second one addresses to social stratification, segmentation of the market. The...

  14. 一类高聚物电子封装材料的分层失效问题%Delamination in a class of generalized plastic IC packaging materials due to thermal load and moisture

    Institute of Scientific and Technical Information of China (English)

    李志刚; 树学峰

    2012-01-01

    对一类具有径向摄动的广义neo-Hookean特征的高聚物电子封装材料在回流焊过程中,由于湿热的联合作用而导致的“爆米花”式的分层失效行为进行了理论研究。给出了此类各向同性不可压材料在包含单一球形孔穴的条件下孔穴的增长和湿热应力之间的解析关系;讨论了孔穴失稳的临界相当应力对初始孔穴率以及径向摄动参数的依赖关系。计算结果表明,当高聚物电子封装材料具有某种缺陷存在时,其孔穴失稳的临界相当应力将会降低,即更易发生“爆米花”式的分层失效。%A representative material cell containing a single microvoid was used to investigate void growth under combined vapor pressure and thermal stress. The plastic IC packaging material was assumed to be a class of generalized neo-Hookean materials. Using the theory of cavity formation and unstable void growth in the incompressible hyper-elastic materials, we gained an analytical relation between the applied traction (moisture-in- duced vapor pressure and thermal stress) and void volume fraction in forementioned materials. The dependence of critical equivalence stress under void instability on initial void rates and radial perturbation parameter was also discussed. Results showed that some perturbation parameters significantly lower the critical stress levels, popcorn failure was more likely to take place.

  15. Asymptotic study of subcritical graph classes

    CERN Document Server

    Drmota, Michael; Kang, Mihyun; Kraus, Veronika; Rué, Juanjo

    2010-01-01

    We present a unified general method for the asymptotic study of graphs from the so-called "subcritical"$ $ graph classes, which include the classes of cacti graphs, outerplanar graphs, and series-parallel graphs. This general method works both in the labelled and unlabelled framework. The main results concern the asymptotic enumeration and the limit laws of properties of random graphs chosen from subcritical classes. We show that the number $g_n/n!$ (resp. $g_n$) of labelled (resp. unlabelled) graphs on $n$ vertices from a subcritical graph class ${\\cG}=\\cup_n {\\cG_n}$ satisfies asymptotically the universal behaviour

  16. Class diagram based evaluation of software performance

    Science.gov (United States)

    Pham, Huong V.; Nguyen, Binh N.

    2013-03-01

    The evaluation of software performance in the early stages of the software life cycle is important and it has been widely studied. In the software model specification, class diagram is the important object-oriented software specification model. The measures based on a class diagram have been widely studied to evaluate quality of software such as complexity, maintainability, reuse capability, etc. However the software performance evaluation based on Class model has not been widely studied, especially for object-oriented design of embedded software. Therefore, in this paper we propose a new approach to directly evaluate the software performance based on class diagrams. From a class diagram, we determine the parameters which are used to evaluate and build formula of the measures such as Size of Class Variables, Size of Class Methods, Size of Instance Variables, Size of Instance Methods, etc. Then, we do analysis of the dependence of performance on these measures and build the performance evaluation function from class diagram. Thereby we can choose the best class diagram based on this evaluation function.

  17. Long-term effects of class size

    OpenAIRE

    Fredriksson, Peter; Öckert, Björn; Oosterbeek, Hessel

    2012-01-01

    This paper evaluates the long-term effects of class size in primary school. We use rich administrative data from Sweden and exploit variation in class size created by a maximum class size rule. Smaller classes in the last three years of primary school (age 10 to 13) are not only beneficial for cognitive test scores at age 13 but also for non-cognitive scores at that age, for cognitive test scores at ages 16 and 18, and for completed education and wages at age 27 to 42. The estimated effect on...

  18. Long-Term Effects of Class Size

    OpenAIRE

    Fredriksson, Peter; Öckert, Björn; Oosterbeek, Hessel

    2011-01-01

    This paper evaluates the long-term effects of class size in primary school. We use rich administrative data from Sweden and exploit variation in class size created by a maximum class size rule. Smaller classes in the last three years of primary school (age 10 to 13) are not only beneficial for cognitive test scores at age 13 but also for non-cognitive scores at that age, for cognitive test scores at ages 16 and 18, and for completed education and wages at age 27 to 42. The estimated effect on...

  19. Long-term effects of class size

    OpenAIRE

    Fredriksson, Peter; Öckert, Björn; Oosterbeek, Hessel

    2011-01-01

    This paper evaluates the long-term effects of class size in primary school. We use rich administrative data from Sweden and exploit variation in class size created by a maximum class size rule. Smaller classes in the last three years of primary school (age 10 to 13) are not only beneficial for cognitive test scores at age 13 but also for non-cognitive scores at that age, for cognitive test scores at ages 16 and 18, and for completed education and wages at age 27 to 42. The estimated effect on...

  20. Class B0631+519: Last of the Class Lenses

    Energy Technology Data Exchange (ETDEWEB)

    York, Tom; Jackson, N.; Browne, I.W.A.; Koopmans, L.V.E.; McKean, J.P.; Norbury, M.A.; Biggs, A.D.; Blandford, R.D.; de Bruyn, A.G.; Fassnacht, C.D.; Myers, S.T.; Pearson, T.J.; Phillips, P.M.; Readhead, A.C.S.; Rusin, D.; Wilkinson, P.N.; /Jodrell Bank /Kapteyn Astron. Inst., Groningen /UC, Davis /JIVE, Dwingeloo /KIPAC, Menlo Park /NFRA,

    2005-05-31

    We report the discovery of the new gravitational lens system CLASS B0631+519. Imaging with the VLA, MERLIN and the VLBA reveals a doubly-imaged flat-spectrum radio core, a doubly-imaged steep-spectrum radio lobe and possible quadruply-imaged emission from a second lobe. The maximum separation between the lensed images is 1.16 arcsec. High resolution mapping with the VLBA at 5 GHz resolves the most magnified image of the radio core into a number of sub-components spread across approximately 20 mas. No emission from the lensing galaxy or an odd image is detected down to 0.31 mJy (5{sigma}) at 8.4 GHz. Optical and near-infrared imaging with the ACS and NICMOS cameras on the HST show that there are two galaxies along the line of sight to the lensed source, as previously discovered by optical spectroscopy. We find that the foreground galaxy at z=0.0896 is a small irregular, and that the other, at z=0.6196 is a massive elliptical which appears to contribute the majority of the lensing effect. The host galaxy of the lensed source is detected in the HST near-infrared imaging as a set of arcs, which form a nearly complete Einstein ring. Mass modeling using non-parametric techniques can reproduce the near-infrared observations and indicates that the small irregular galaxy has a (localized) effect on the flux density distribution in the Einstein ring at the 5-10% level.

  1. Inclusion relations between classes of hypergeometric functions

    Directory of Open Access Journals (Sweden)

    O. P. Ahuja

    1994-01-01

    Full Text Available The use of hypergeometric functions in univalent function theory received special attention after the surprising application of such functions by de Branges in the proof of the 70-year old Bieberbach Conjecture. In this paper we consider certain classes of analytic functions and examine the distortion and containment properties of generalized hypergeometric functions under some operators in these classes.

  2. The Use of Virtual Media Laboratory to Increase Students’ Motivation on Direct Current Circuits Materials at Class X of MAN I Pekanbaru

    OpenAIRE

    Emhadelima Emhadelima

    2015-01-01

    The purpose of the study is to determine whether there is a significance effect on the use of Practicum methods by using Crocodile Program combined with lectures, question and answer activities give significant effect on  students’ activities in learning electricity simple lesson and to identify whether the use of the simulation lab provides better results than the traditional lab on learning outcomes. 36 natural science students was involved in the study. The data was analyzed by using t-tes...

  3. A New Class of Octahedral Molecular Sieve Materials for the Selective Removal and Sequestration of {sup 90}Sr{sup 2+}

    Energy Technology Data Exchange (ETDEWEB)

    NYMAN,MAY D.; NENOFF,TINA M.; TRIPATHI,AKHILESH; PARISE,JOHN B.; MAXWELL,ROBERT S.; HARRISON,WILLIAM T.A.

    2000-07-14

    The structure of Na{sub 16}Nb{sub 12.8}Ti{sub 3.2}O{sub 44.8}(OH){sub 3.2} {center_dot} 8H{sub 2}O, a member of a new family of Sandia Octahedral Molecular Sieves (SOMS) having a Nb/Na/M{sup IV} (M= Ti, Zr) oxide framework and exchangeable Na and water in open channels, was determined from Synchrotron X-ray data. The SOMS phases are isostructural with variable M{sup IV}:Nb(1:50--1:4) ratios. The SOMS are extremely selective for sorption of divalent cations, particularly Sr{sup 2+}. The ion-exchanged SOMS undergo direct thermal conversion to a perovskite-type phase, indicating this is a promising new method for removal and sequestration of radioactive Sr-90 from mixed nuclear wastes.

  4. A Class of Binomial Permutation Polynomials

    OpenAIRE

    Tu, Ziran; Zeng, Xiangyong; Hu, Lei; Li, Chunlei

    2013-01-01

    In this note, a criterion for a class of binomials to be permutation polynomials is proposed. As a consequence, many classes of binomial permutation polynomials and monomial complete permutation polynomials are obtained. The exponents in these monomials are of Niho type.

  5. Material properties of Ni-Cr-Al alloy and design of a 4 GPa class non-magnetic high-pressure cell

    International Nuclear Information System (INIS)

    The Ni-Cr-Al Russian alloy was prepared. Its magnetic and mechanical properties were better than those of MP35N alloy. We fabricated the a piston-cylinder-type hybrid high-pressure cell using the Ni-Cr-Al alloy. It has been found that the maximum working pressure can be repeatedly raised to 3.5 GPa at T = 2 K without any difficulties

  6. A CLASS OF IPPS SAMPLING SCHEMES

    Directory of Open Access Journals (Sweden)

    L.N. Sahoo1# ; S.C. Senapati**2; A.K. Mangaraj***

    2010-09-01

    Full Text Available This paper introduces a general class of Inclusion Probability Proportional to Size (IPPS sampling schemes for selecting two units from a finite population. All IPPS sampling schemes, identified as particular members of this class, possess some desirable properties with regard to the inclusion probabilities, and provide unbiased and non-negative variance estimators under Horvitz-Thomson (HT model.

  7. Python Classes for Numerical Solution of PDE's

    OpenAIRE

    Asif Mushtaq; Trond Kvamsdal; Kare Olaussen

    2015-01-01

    We announce some Python classes for numerical solution of partial differential equations, or boundary value problems of ordinary differential equations. These classes are built on routines in \\texttt{numpy} and \\texttt{scipy.sparse.linalg} (or \\texttt{scipy.linalg} for smaller problems).

  8. A new Class of Extremal Composites

    DEFF Research Database (Denmark)

    Sigmund, Ole

    2000-01-01

    The paper presents a new class of two-phase isotropic composites with extremal bulk modulus. The new class consists of micro geometrics for which exact solutions can be proven and their bulk moduli are shown to coincide with the Hashin-Shtrikman bounds. The results hold for two and three dimensio...

  9. Ultrasonic Processing of Materials

    Energy Technology Data Exchange (ETDEWEB)

    Meek, Thomas T.; Han, Qingyou; Jian, Xiaogang; Xu, Hanbing

    2005-06-30

    The purpose of this project was to determine the impact of a new breakthrough technology, ultrasonic processing, on various industries, including steel, aluminum, metal casting, and forging. The specific goals of the project were to evaluate core principles and establish quantitative bases for the ultrasonc processing of materials, and to demonstrate key applications in the areas of grain refinement of alloys during solidification and degassing of alloy melts. This study focussed on two classes of materials - aluminum alloys and steels - and demonstrated the application of ultrasonic processing during ingot casting.

  10. MFV-Class:a multi-faceted visualization tool of object classes

    Institute of Scientific and Technical Information of China (English)

    张志猛; 潘云鹤; 庄越挺

    2004-01-01

    Classes are key software components in an object-oriented software system. In many industrial OO software systems,there are some classes that have complicated structure and relationships. So in the processes of software maintenance,testing,software reengineering,software reuse and software restructure,it is a challenge for software engineers to understand these classes thoroughly. This paper proposes a class comprehension model based on constructivist learning theory,and implements a software visualization tool(MFV-Class)to help in the comprehension of a class. The tool provides multiple views of class to uncover manifold facets of class contents. It enables visualizing three object-oriented metrics of classes to help users focus on the understanding process. A case study was conducted to evaluate our approach and the toolkit.

  11. Price Responsiveness of Wheat Class Demands

    OpenAIRE

    Gallagher, Paul; Wilson, William W.; Riepe, Jean

    1988-01-01

    This paper identifies the price responsiveness and preferences for wheat classes using a "Case" Function specification. Results indicate there have been numerous changes in market shares of wheat classes from the different exporters in specific markets. In general, quality differentials are important in some international markets, whereas others are very price responsive.

  12. PENELOPE. Taking advantage of Class II simulation

    International Nuclear Information System (INIS)

    PENELOPE is a general-purpose Monte Carlo code for the simulation of electron-photon showers in arbitrary materials. It covers the energy range from ∼1 keV up to ∼1 GeV. The simulation of electron and positron transport is based on a mixed (Class II) simulation scheme. The cut-off angular deflection, which separates soft and hard (catastrophic) elastic collisions, is allowed to vary with the energy of the particle in such a way that the multiple soft interactions which occur between two consecutive hard events produce only gentle deflections of the track. Space displacements are generated by a simple and accurate algorithm that works even in the vicinity of interfaces. The physics of PENELOPE, the simulation algorithm for charged particle transport and the structure and operation of the code system are described. The distribution package also includes subroutines for simulation in quadric geometries (i.e. material systems consisting of homogeneous bodies limited by quadric surfaces) and a simple geometry viewer. (author)

  13. The Continuing Story of Class IIa Bacteriocins

    Science.gov (United States)

    Drider, Djamel; Fimland, Gunnar; Héchard, Yann; McMullen, Lynn M.; Prévost, Hervé

    2006-01-01

    Many bacteria produce antimicrobial peptides, which are also referred to as peptide bacteriocins. The class IIa bacteriocins, often designated pediocin-like bacteriocins, constitute the most dominant group of antimicrobial peptides produced by lactic acid bacteria. The bacteriocins that belong to this class are structurally related and kill target cells by membrane permeabilization. Despite their structural similarity, class IIa bacteriocins display different target cell specificities. In the search for new antibiotic substances, the class IIa bacteriocins have been identified as promising new candidates and have thus received much attention. They kill some pathogenic bacteria (e.g., Listeria) with high efficiency, and they constitute a good model system for structure-function analyses of antimicrobial peptides in general. This review focuses on class IIa bacteriocins, especially on their structure, function, mode of action, biosynthesis, bacteriocin immunity, and current food applications. The genetics and biosynthesis of class IIa bacteriocins are well understood. The bacteriocins are ribosomally synthesized with an N-terminal leader sequence, which is cleaved off upon secretion. After externalization, the class IIa bacteriocins attach to potential target cells and, through electrostatic and hydrophobic interactions, subsequently permeabilize the cell membrane of sensitive cells. Recent observations suggest that a chiral interaction and possibly the presence of a mannose permease protein on the target cell surface are required for a bacteria to be sensitive to class IIa bacteriocins. There is also substantial evidence that the C-terminal half penetrates into the target cell membrane, and it plays an important role in determining the target cell specificity of these bacteriocins. Immunity proteins protect the bacteriocin producer from the bacteriocin it secretes. The three-dimensional structures of two class IIa immunity proteins have been determined, and it has

  14. Presence of Third Molar Germs in Orthodontic Patients with Class II/2 and Class III Malocclusions

    OpenAIRE

    Maričić, Barbara Mady; Legović, Mario; Šlaj, Martina; Lapter Varga, Marina; Žuvić Butorac, Marta; Kapović, Miljenko

    2009-01-01

    The aim of this study was to determine the presence of third molar germs in patients with Class II/2 and Class III malocclusions. The study comprised 146 examinees from Zagreb and Istria. Examinees with Class II/2 malocclusions amounted to 77 and those with Class III 69. With regard to development of dentition the examinees were divided into two groups: Group I subjects with early mixed dentition (23 subjects with Class II/2 and 21 subjects with Class III), and Group II subjects with late mix...

  15. Motivation in Physical Education classes of senior high school grades

    Directory of Open Access Journals (Sweden)

    Karen Cristina Chicati

    2008-06-01

    Full Text Available The aim of the present investigation was to make a diagnosis and analyze students’ motivation in Physical Education classes of the senior high school of the public school system in the city of Maringá, state of Paraná, Brazil. This descriptive research comprised a population of 12,889 students, males and females, with 15-to-17-year average age, enrolled in the three grades of senior high school. The sample comprised 240 students randomly selected from four schools: 60 students per school, 20 from each grade, 10 males and 10 females. A questionnaire constituted by 16 mixed questions was applied to the students. The data were analyzed through frequency and percentage calculus. The results demonstrated that Physical Education classes are not so highly motivated, once the students have been given the same contents since the first grades, prevailing sports. Command and open teaching have been the most frequently used methodology, despite most of the students answering that they do what they want to in class. Evaluation comprises attendance and theoretical/practical classes. The students demonstrated a strong interest in classes, but those who are not so much interested answered that the classes were demotivating, besides backing appropriate materials and space. Thus it may be concluded that students motivation in Physical Education classes in the senior high school grades is not so clear.

  16. Design of a class 1 safety valve

    International Nuclear Information System (INIS)

    Spring-loaded safety valves are used to protect the over-pressurization of fluid systems or pressure vessels. The valves are required to open for the pressure mitigation and reseat after the system pressure is reduced to a certain value. Due to its critical role in power plants, the structural integrity of the valve is highly demanded. In nuclear power application, the design of the valve is required to comply with the provisions in the codes and standards. In many countries, nuclear service safety valves are designed to the requirements of ASME Section III. In Korea, KEPIC (Korea Electric Power Industry Code) as well as ASME Section III is accepted as the standards for the design and manufacturing of nuclear equipment as specified in the Notice No. 2000-17 of the MOST (Ministry of Science and Technology). To date, the maintenance of safety related valves has been principally relied on by overseas technology, if significant failure was found during the valve operation. This is mainly due to the fact that nuclear service safety valves were not developed domestically until a recent date. In the last two years, KEPRI has developed a MSSV (Main Steam Safety Valve) in cooperation with Jokwang I.L.I. Co. In the design process, the structural adequacy of the valve was assessed as a safety Class 1 valve by principally relying on the FE (Finite Element) technique. Actually, the valve can be designed to the requirement of a Class 2 valve. In spite of the industrial interest, there are few design materials which could be referred to. Therefore, delineation of a design procedure for nuclear equipment is claimed. To this end, the assessment procedure for the safety valve structure is discussed in the present study based on KEPIC MNB (or ASME Section III NB)

  17. Generation of proper classes of short exact sequences

    OpenAIRE

    Ali Pancar

    1997-01-01

    The generation of proper classes of short exact sequences of modules by subclasses is considered. The class generated by two proper classes is studied by means of some operations between these classes. These operations are investigated in details for classes of short quasi-splitting, torsion-splitting and pure exact sequences of abelian groups.

  18. Universality Class of Fluctuating Pulled Fronts

    International Nuclear Information System (INIS)

    It has recently been proposed that fluctuating 'pulled' fronts propagating into an unstable state should not be in the standard Kardar-Parisi-Zhang (KPZ) universality class for rough interface growth. We introduce an effective field equation for this class of problems, and show on the basis of it that noisy pulled fronts in d+1 bulk dimensions should be in the universality class of the ((d+1)+1) D KPZ equation rather than of the (d+1)D KPZ equation. Our scenario ties together a number of heretofore unexplained observations in the literature, and is supported by previous numerical results

  19. Is Active Learning Like Broccoli? Student Perceptions of Active Learning in Large Lecture Classes

    Science.gov (United States)

    Smith, C. Veronica; Cardaciotto, LeeAnn

    2011-01-01

    Although research suggests that active learning is associated with positive outcomes (e.g., memory, test performance), use of such techniques can be difficult to implement in large lecture-based classes. In the current study, 1,091 students completed out-of-class group exercises to complement course material in an Introductory Psychology class.…

  20. Automatic Identification Systems the Effects of Class B on the Use of Class A Systems

    Science.gov (United States)

    Norris, Andy

    2006-05-01

    The standards for CSTDMA Class B AIS will shortly be published by the International Electrotechnical Commission and equipment will become available during 2006. The perceived benefits that Class B brings to leisure craft users and its relatively low cost will make it attractive in the market place. A rapid take-up of Class B use can therefore be expected. This paper considers the impact that increased use of Class B will have on users of Class A AIS that are compulsorily fitted to larger vessels to meet the requirements of the International Maritime Organization Safety of Life at Sea convention. The CSTDMA Class B system has been designed to prevent overloading of the AIS VHF data link. This is briefly reviewed but there are a number of other aspects that need to be considered. These include: the increased garbling of Class B messages compared to those of Class A; the problems accruing from the low update rate of Class B information; the increase in display information that will need to be managed; and the possible increase in inappropriate manoeuvres of leisure craft caused by misplaced reliance on AIS. As a result of the investigation the paper highlights the fact that Class B users must not assume that their own presence, in the form of Class B transmissions, will be particularly visible on the bridge of many SOLAS vessels. This will continue to be the case for many years into the future, until such vessels are mandated to carry radar with AIS target overlay capability.

  1. Class, Mothering and the Values of Food

    DEFF Research Database (Denmark)

    Aamann, Iben Charlotte

    2015-01-01

    The data analysed in this empirical paper stems from ethnographic fieldwork among new school parents at three Danish primary schools. I draw on empirically grounded theories on the cultural and subjective dimensions of class, inspired by the “English School” of poststructuralist informed, feminist...... scholars, to explore how class matters. Using the values ascribed to food at social arrangements as a lens, I explore different ways of doing class and mothering: through the exchange value of the food, through its use value and through its healthiness. I conclude by arguing that food studies hold a huge...

  2. Two decades of Neo-Marxist class analysis and health inequalities: A critical reconstruction

    OpenAIRE

    MUNTANER, CARLES; Ng, Edwin; Chung, Haejoo; Prins, Seth J

    2015-01-01

    Most population health researchers conceptualize social class as a set of attributes and material conditions of life of individuals. The empiricist tradition ofclass as an individual attribute' equates class to an ‘observation', precluding the investigation of unobservable social mechanisms. Another consequence of this view of social class is that it cannot be conceptualized, measured, or intervened upon at the meso- or macro levels, being reduced to a personal attribute. Thus, population h...

  3. The Science of Materials: from Materials Discovered by Chance to Customized Materials

    OpenAIRE

    Bréchet, Yves; Haroche, Serge

    2015-01-01

    Throughout the ages, humans have applied knowledge and know-how to master materials. They have gone from materials encountered by chance available in their environment to customized materials designed to meet multi-criteria specifications. Today, owing particularly to digital modelling on different scales, we are able to design high-performance materials, combining various classes of materials, in controlled geometries and dimensions. These innovation strategies – architectured or bio-inspire...

  4. A new model of social class : findings from the BBC's Great British Class Survey Experiment.

    OpenAIRE

    Savage, Mike; Devine, Fiona; Cunningham, Niall; Taylor, Mark; Li, Yaojun; Hjellbrekke, Johs.; Le Roux, Brigitte; Friedman, Sam; Miles, Andrew

    2013-01-01

    The social scientific analysis of social class is attracting renewed interest given the accentuation of economic and social inequalities throughout the world. The most widely validated measure of social class, the Nuffield class schema, developed in the 1970s, was codified in the UK’s National Statistics Socio-Economic Classification (NS-SEC) and places people in one of seven main classes according to their occupation and employment status. This principally distinguishes between people workin...

  5. The State of the Australian Middle Class

    Directory of Open Access Journals (Sweden)

    Clive Hamilton

    2008-09-01

    Full Text Available There is a widespread view that the middle class in Australia is doing it tough, that they arefinding it increasingly difficult to maintain a decent standard of living and are suffering frommortgage stress. Indeed, some media reports have announced the end of the middle classdream.This paper tests a number of these popular views against the statistical data. It asks whetherthe typical Australian family can be said to be struggling? Are mortgages creating severeproblems for middle-class families? Is the middle class shrinking? Are families copingfinancially only because wives are going out to work?

  6. Social Class (In)Visibility and the Professional Experiences of Middle-Class Novice Teachers

    Science.gov (United States)

    Hall, David; Jones, Lisa

    2013-01-01

    This article focuses upon the classed and early professional experiences of middle-class novice teachers in England experiencing and contemplating working in schools serving socio-economically disadvantaged communities. Through an examination of the visibility and invisibility of social class in education set within an increasingly unequal and…

  7. A new class of variational equation problems

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Applying an analysis method to a group of multivariable equations, a new class of variational equations are proved. This method is more concise and more direct than the others. This result can be applied to some stochastic control models.

  8. On Hereditary Helly classes of graphs

    Directory of Open Access Journals (Sweden)

    Marina Groshaus

    2008-01-01

    Full Text Available In graph theory, the Helly property has been applied to families of sets, such as cliques, disks, bicliques, and neighbourhoods, leading to the classes of clique-Helly, disk-Helly, biclique-Helly, neighbourhood-Helly graphs, respectively. A natural question is to determine for which graphs the corresponding Helly property holds, for every induced subgraph. This leads to the corresponding classes of hereditary clique-Helly, hereditary disk-Helly, hereditary biclique-Helly and hereditary neighbourhood-Helly graphs. In this paper, we describe characterizations in terms of families of forbidden subgraphs, for the classes of hereditary biclique-Helly and hereditary neighbourhood-Helly graphs. We consider both open and closed neighbourhoods. The forbidden subgraphs are all of fixed size, implying polynomial time recognition for these classes.

  9. Perspective through the 1st class innovation award-innovation in the key materials

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    @@ Directed by Prof.Litong Zhang (Member of CAS)from Northwestern Polytechnical University, the project on the topic of ceramic matrix composite, which sustains high temperature, resists oxidization, and has a long lifetime,achieved the 1st class National Technology Innovation Award in 2004.

  10. 49 CFR 173.469 - Tests for special form Class 7 (radioactive) materials.

    Science.gov (United States)

    2010-10-01

    ... the test material, such as the use of non-radioactive contents, must be taken into account in... (radioactive) material contained in a sealed capsule need not be subjected to— (1) The impact test and the percussion test of this section provided that the mass of the special form radioactive material is less...

  11. Evolution of major histocompatibility complex class I and class II genes in the brown bear

    Directory of Open Access Journals (Sweden)

    Kuduk Katarzyna

    2012-10-01

    Full Text Available Abstract Background Major histocompatibility complex (MHC proteins constitute an essential component of the vertebrate immune response, and are coded by the most polymorphic of the vertebrate genes. Here, we investigated sequence variation and evolution of MHC class I and class II DRB, DQA and DQB genes in the brown bear Ursus arctos to characterise the level of polymorphism, estimate the strength of positive selection acting on them, and assess the extent of gene orthology and trans-species polymorphism in Ursidae. Results We found 37 MHC class I, 16 MHC class II DRB, four DQB and two DQA alleles. We confirmed the expression of several loci: three MHC class I, two DRB, two DQB and one DQA. MHC class I also contained two clusters of non-expressed sequences. MHC class I and DRB allele frequencies differed between northern and southern populations of the Scandinavian brown bear. The rate of nonsynonymous substitutions (dN exceeded the rate of synonymous substitutions (dS at putative antigen binding sites of DRB and DQB loci and, marginally significantly, at MHC class I loci. Models of codon evolution supported positive selection at DRB and MHC class I loci. Both MHC class I and MHC class II sequences showed orthology to gene clusters found in the giant panda Ailuropoda melanoleuca. Conclusions Historical positive selection has acted on MHC class I, class II DRB and DQB, but not on the DQA locus. The signal of historical positive selection on the DRB locus was particularly strong, which may be a general feature of caniforms. The presence of MHC class I pseudogenes may indicate faster gene turnover in this class through the birth-and-death process. South–north population structure at MHC loci probably reflects origin of the populations from separate glacial refugia.

  12. The economic basis of social class

    OpenAIRE

    John H. Goldthorpe; McKnight, Abigail

    2004-01-01

    In this paper we adopt a theory of class positions based on employment relations to assess what implications individuals¿ class positions have for their economic life. In particular we consider economic security (the risk of unemployment), economic stability (the variability component in earnings) and economic prospects (lifetime earnings profiles). Our findings provide empirical support for the theory itself and little evidence for the currently fashionable claims of the decline, or even dea...

  13. On hereditary Helly classes of graphs

    OpenAIRE

    Marina Groshaus; Jayme Luiz Szwarcfiter

    2008-01-01

    In graph theory, the Helly property has been applied to families of sets, such as cliques, disks, bicliques, and neighbourhoods, leading to the classes of clique-Helly, disk-Helly, biclique-Helly, neighbourhood-Helly graphs, respectively. A natural question is to determine for which graphs the corresponding Helly property holds, for every induced subgraph. This leads to the corresponding classes of hereditary clique-Helly, hereditary disk-Helly, hereditary biclique-Helly and hereditar...

  14. A Simple Class of Measures of Skewness

    OpenAIRE

    ALTINAY, Galip

    2016-01-01

    In this paper, a simple class of measures for detecting skewness in samples is introduced. The new class of measures is based on a new definition of skewness that takes midrange into consideration. The proposed coefficients of skewness can be computed easily with only three of the summary statistics, i.e., the minimum value, the maximum value and the median (or the mode, or the mean). Another advantage of the new statistics is that they are bounded by -1 and +1, hence, the coefficients of ske...

  15. Pyroxenes: a new class of multiferroics

    International Nuclear Information System (INIS)

    Pyroxenes with the general formula AMSi2O6 (A = mono- or divalent metal, M = di- or trivalent metal) are shown to be a new class of multiferroic materials. In particular, we have found so far that NaFeSi2O6 becomes ferroelectric in a magnetically ordered state below ∼6 K. Similarly, magnetically driven ferroelectricity is also detected in the Li homologues, LiFeSi2O6 (TC∼18 K) and LiCrSi2O6 (TC∼11 K). In all these monoclinic systems the electric polarization can be strongly modified by magnetic fields. Measurements of magnetic susceptibility, pyroelectric current and dielectric constants (and their dependence on magnetic field) are performed using a natural crystal of aegirine (NaFeSi2O6) and synthetic crystals of LiFeSi2O6 and LiCrSi2O6 grown from melt solution. For NaFeSi2O6 a temperature versus magnetic field phase diagram is proposed. Exchange constants are computed on the basis of ab initio band structure calculations. The possibility of a spiral magnetic structure caused by frustration to be the reason for the origin of the multiferroic behaviour is discussed. We propose that other pyroxenes may also be multiferroic, and that the versatility of this family offers an exceptional opportunity to study general conditions for and mechanisms of magnetically driven ferroelectricity. (fast track communication)

  16. Prediction of class membership of biodiesels using chemometrics.

    Science.gov (United States)

    Mustafa, Zylia; Milina, Rumyana; Simeonova, Pavlina A; Tsakovski, Stefan L; Simeonov, Vasil D

    2015-01-01

    Recently, serious scientific and technological attention is paid to creation of alternative energy sources, including biofuels. The assessment of the quality of the biofuels produced and of the raw materials needed for the production technology is an important scientific challenge. One of the major sources for biodiesel production is plant oils material (sunflower, rapeseed, palm, soya etc.). Since plants are complex system from the biota it is not easy to find specific chemical components responsible for their ability to serve as biodiesels. The characterization and classification of plant sources as biofuel material could be reliably estimated only by the use of multivariate statistical approaches (chemometrics). The chemometric expertise makes it possible not only to classify different biofuel sources into similarity classes but also to predict the membership of unknown by origin chemically analyzed samples to already existing classes. The present study deals with the prediction of the class membership of several unknown by origin samples, which are included in a large data set with FAME profiles of biodiesel plant sources. Using a data set from chromatographic analysis of fatty acid methyl esters profiles (FAME) of different plant biodiesel sources and applying the chemometric technique know as partial least squares-discriminant analysis (PLS - DA) a pattern recognition procedure is developed to: I. Model classes of similarity of biodiesel plant sources using their FAME profiles not taking into account the samples with unknown origin; II. Classify correctly the samples with unknown origin to the previously defined classes of biodiesel sources (palm oil, soybean oil, peanut oil, rapeseed oil, sunflower oil and maize oil). The prediction is successfully achieved for all samples with previously unknown origin. This pattern recognition approach is applied for the first time in the field of biodiesel classification and modeling tasks. PMID:25438133

  17. Classes and Theories of Trees Associated with a Class Of Linear Orders

    DEFF Research Database (Denmark)

    Goranko, Valentin; Kellerman, Ruaan

    2011-01-01

    classes of trees and between their corresponding first-order theories. We then obtain some general results about the axiomatization of the first-order theories of some of these classes of trees in terms of the first-order theory of the generating class C, and indicate the problems obstructing such general...... results for the other classes. These problems arise from the possible existence of nondefinable paths in trees, that need not satisfy the first-order theory of C, so we have started analysing first order definable and undefinable paths in trees....

  18. Class and ideological orientations revisited: an exploration of class-based mechanisms.

    Science.gov (United States)

    Bengtsson, Mattias; Berglund, Tomas; Oskarson, Maria

    2013-12-01

    Studies of the relationship between class position and political outlooks still only have a limited understanding of the class-related mechanisms that matter for ideological orientations. This article presents a comprehensive analysis of the mechanisms that link class position and left/right and authoritarian/libertarian orientations. Besides main factors such as income, career prospects, job security, education, class origin and class identification, the significance of work-related factors such as work autonomy, working in a team, a physically demanding job and a mentally demanding job is studied. The findings are based on a survey specifically designed for this purpose and collected in Sweden in 2008/2009. A great deal of the association between class position and left/right orientations is explained by socio-economic conditions; different classes sympathize with policies that will benefit them economically. Another important factor is class identification. Work-related factors also have relevance, but the effect of class position on left/right orientations works mainly through the remuneration system. Class position is also related to authoritarian/libertarian orientations. However, this relationship is less explained by socio-economic position per se, but is rather an effect of the educational system and its allocation of the workforce into different class positions. It also turns out that work-related factors do not explain the class effects; however, a physically demanding job shows a unique effect. Overall, our findings suggest that besides factors such as class position, income, education and class identification, we need to consider work-related aspects to derive a more complete understanding of the distribution of ideological orientations in Western societies. PMID:24320072

  19. A Checklist of Navicula (Class Bacillariophyceae) of the Philippines

    OpenAIRE

    Milagrosa Martinez-Goss

    2001-01-01

    A unified acocunt of all known diatoms in the genus Navicula, class Bacillariophyceae, of the Philippines from 1886 to 1987 is presented. A total of 226 taxa are listed. Included herewith are the references that originally described or cited the taxon and the ecological/habitat records for each taxon. As much as possible, a list of exsciccata materials is given together with their repository places.

  20. Students' different understandings of class diagrams

    Science.gov (United States)

    Boustedt, Jonas

    2012-03-01

    The software industry needs well-trained software designers and one important aspect of software design is the ability to model software designs visually and understand what visual models represent. However, previous research indicates that software design is a difficult task to many students. This article reports empirical findings from a phenomenographic investigation on how students understand class diagrams, Unified Modeling Language (UML) symbols, and relations to object-oriented (OO) concepts. The informants were 20 Computer Science students from four different universities in Sweden. The results show qualitatively different ways to understand and describe UML class diagrams and the "diamond symbols" representing aggregation and composition. The purpose of class diagrams was understood in a varied way, from describing it as a documentation to a more advanced view related to communication. The descriptions of class diagrams varied from seeing them as a specification of classes to a more advanced view, where they were described to show hierarchic structures of classes and relations. The diamond symbols were seen as "relations" and a more advanced way was seeing the white and the black diamonds as different symbols for aggregation and composition. As a consequence of the results, it is recommended that UML should be adopted in courses. It is briefly indicated how the phenomenographic results in combination with variation theory can be used by teachers to enhance students' possibilities to reach advanced understanding of phenomena related to UML class diagrams. Moreover, it is recommended that teachers should put more effort in assessing skills in proper usage of the basic symbols and models and students should be provided with opportunities to practise collaborative design, e.g. using whiteboards.

  1. Group cohesion in exercise classes: An examination of gender and type of exercise class differences

    Directory of Open Access Journals (Sweden)

    Hülya Aşçı

    2011-10-01

    Full Text Available Group cohesion has been attributed to the higher levels of attendance and performance and lower levels of drop-outs in exercise classes. Cohesion can be affected by different type of exercise classes and gender. Therefore, the main purpose of the study was to compare the group cohesion levels of martial arts participants (aikido, taekwondo, karate, and kendo with aerobic-like participants (aerobics, aero-steps, phys-gym, and high-low aerobics. This causal comparative study also aimed at examining sex differences in group cohesion in exercise classes. There were 140 participants (Mage=28.1 SD= 8.01 and female= 138 male= 2 in aerobic-like classes and 137 participants (Mage= 22.2 SD= 3.8 and female= 48 male= 89 in martial arts classes. Results revealed no sex differences between the groups on the perceptions of cohesion. On the other hand, except for individual attractions to the group-task dimension, participants of martial art classes had higher levels of group cohesion than the participants of aerobic-like classes. Consequently, it was concluded that different types of exercise classes may have different levels of cohesion and those differences were discussed within the context of exercise classes.

  2. Group cohesion in exercise classes: An examination of gender and type of exercise class differences

    Directory of Open Access Journals (Sweden)

    Selçuk Akpınar

    2011-10-01

    Full Text Available Group cohesion has been attributed to the higher levels of attendance and performance and lower levels of drop-outs in exercise classes. Cohesion can be affected by different type of exercise classes and gender. Therefore, the main purpose of the study was to compare the group cohesion levels of martial arts participants (aikido, taekwondo, karate, and kendo with aerobic-like participants (aerobics, aero-steps, phys-gym, and high-low aerobics. This causal comparative study also aimed at examining gender differences in group cohesion in exercise classes. There were 140 participants (Mage=28.1 SD= 8.01 and female= 138 male= 2 in aerobic-like classes and 137 participants (Mage= 22.2 SD= 3.8 and female= 48 male= 89 in martial arts classes. Results revealed no gender differences between the groups on the perceptions of cohesion. On the other hand, except for individual attractions to the group-task dimension, participants of martial art classes had higher levels of group cohesion than the participants of aerobic-like classes. Consequently, it was concluded that different types of exercise classes may have different levels of cohesion and those differences were discussed within the context of exercise classes

  3. Teachers’ perspectives on flipping the language class: More than creating materials

    OpenAIRE

    Peters, Mitchell Joseph; Calzas Hernández, María; Jara Maroto, Concepción; Díaz Garrido, Ana Isabel; Fernández Chaves, Ismael; López Lago, Miguel Ángel; Marcos Miguel, Nausica; Rivas Reyes, Mirian

    2015-01-01

    Higher education in the 21st century is distinguished by accelerating technological adoption, offering key challenges and new opportunities (NMC, 2015). This phenomenon has significant impact on teaching and learning, including the emergence of new trends such as the flipped classroom methodology. University leadership encourages the adoption of this methodology in both content classes as well as in language instruction. Creating a flipped classroom learning design implies that a teacher e...

  4. Evaluation depth of the curve of Spee in class I, class II, and class III malocclusion: A cross sectional study

    Directory of Open Access Journals (Sweden)

    Sanjna Nayar

    2015-01-01

    Full Text Available Occlusal plane is an essential consideration when multiple long-span posterior restorations are designed. When restorations are added to an existing tooth arrangement characterized by rotated, tipped, or extruded teeth, excursive interferences may be incorporated, resulting in detrimental squeal. The curve of Spee, which exists in the ideal natural dentition, allows harmony to exist between the anterior tooth and condylar guidance. This curve exists in the sagittal plane and is the best viewed from a lateral aspect. It permits total posterior disclusion on mandibular protrusion, given proper anterior tooth guidance. It is unclear that whether the curve of Spee is a description of the occlusal surface of each arch separately or in maximal intercuspation. The purpose of this study was to examine the differences in the depth of curve of Spee between the class I, class II, class III and to investigate the relationship of depth of curve of Spee with over jet, over-bite.

  5. APPLICATION OF TWO OPERATORS TRANSFORM FROM CLASS A OPERATOR TO THE CLASS OF HYPONORMAL OPERATOR

    Institute of Scientific and Technical Information of China (English)

    Yang Changsen; Ding Yanfeng

    2011-01-01

    In this article, we give an operator transform (∧T)(*) from class A operator to the class of hyponormal operators. It is different from the operator transform (∧T) defined by M.Chō and T. Yamazaki. Then, we show that σ(T) = σ(∧T)(*)) and σa(T)\\{0} = σa(∧T)(*))\\{0},in case T belongs to class A. Next, we obtain some relations between (∧T) and (∧T)(*).

  6. Postura de cabeça nas deformidades dentofaciais classe II e classe III Head posture in the presence of class II and class III dentofacial deformities

    Directory of Open Access Journals (Sweden)

    Marcela Ralin de Carvalho Deda

    2012-04-01

    Full Text Available OBJETIVO: este estudo investiga se existe diferença entre grupos com diferentes deformidades dentofaciais (padrão classe II e classe III e o grupo sem a deformidade em relação à postura de cabeça. MÉTODO: participaram deste estudo, voluntariamente, 25 pacientes (entre 16 e 40 anos. Dez pacientes com diagnóstico de deformidade dentofacial classe II e 15 pacientes com o diagnóstico de classe III esquelética e 15 voluntários sadios, com equivalência em sexo e idade ao grupo de deformidade, formando o grupo controle. Primeiramente foi realizada a inspeção da postura de cabeça. Logo em seguida foi realizada a avaliação postural de cabeça por meio da fotografia postural (fotogrametria. RESULTADOS: não houve diferença significante (p>0,05 entre os grupos em relação à avaliação postural utilizando-se a fotogrametria. Já em relação à avaliação postural pela inspeção clínica, observou-se uma postura anterior de cabeça nos indivíduos com a deformidade dentofacial padrão classe II, comparados ao padrão classe III (p = 0,001 e ao grupo controle (p = 0,001. Foi visto também que o grupo deformidade classe II apresentou um percentual inferior de indivíduos com posição neutra de cabeça comparado ao grupo deformidade classe III (p = 0,008 e ao grupo controle (p = 0,001. CONCLUSÃO: indivíduos com deformidade dentofacial classe II podem apresentar uma anteriorização de cabeça. Não há influência da deformidade no aumento ou na redução do ângulo cabeça-pescoço, analisado por meio da fotogrametria.PURPOSE: this study investigates whether there is a difference in head posture between groups with different dentofacial deformities (class II and class III and a group with no deformity. METHOD: 25 volunteers aged from 16 to 40 year old took part in the study. Ten patients had a diagnosis of class II dentofacial deformity, 15 had a diagnosis of class III skeletal deformity, and 15 healthy volunteers matched for sex and

  7. Fibonacci family of dynamical universality classes.

    Science.gov (United States)

    Popkov, Vladislav; Schadschneider, Andreas; Schmidt, Johannes; Schütz, Gunter M

    2015-10-13

    Universality is a well-established central concept of equilibrium physics. However, in systems far away from equilibrium, a deeper understanding of its underlying principles is still lacking. Up to now, a few classes have been identified. Besides the diffusive universality class with dynamical exponent [Formula: see text], another prominent example is the superdiffusive Kardar-Parisi-Zhang (KPZ) class with [Formula: see text]. It appears, e.g., in low-dimensional dynamical phenomena far from thermal equilibrium that exhibit some conservation law. Here we show that both classes are only part of an infinite discrete family of nonequilibrium universality classes. Remarkably, their dynamical exponents [Formula: see text] are given by ratios of neighboring Fibonacci numbers, starting with either [Formula: see text] (if a KPZ mode exist) or [Formula: see text] (if a diffusive mode is present). If neither a diffusive nor a KPZ mode is present, all dynamical modes have the Golden Mean [Formula: see text] as dynamical exponent. The universal scaling functions of these Fibonacci modes are asymmetric Lévy distributions that are completely fixed by the macroscopic current density relation and compressibility matrix of the system and hence accessible to experimental measurement. PMID:26424449

  8. A GENERALIZED CLASS OF PSNR SAMPLING SCHEME

    Directory of Open Access Journals (Sweden)

    D. Shukla

    2010-01-01

    Full Text Available In the present days of advanced electronic technologies in the field of communicationlike mobile phones, e-mail, internet etc. (and so forth the incentive based mail surveys are beingpopular due to their cost effectiveness and rapid approach to individuals. But, a majordisadvantage appears as mail surveys are affected by a huge amount of non-response of units inthe sample. The post-stratified non-response (PSNR scheme is used, in the stratified samplingset-up, when (i frames of stratum are unknown and (ii strata contain some non-responding units.This paper presents a general class of PSNR type sampling scheme by introducing three groupsof earmarked strata based on response pattern along-with two parameters pf the class. TheBayesian approach regarding utilization of prior knowledge (or guess of response pattern isintroduced in the proposed class for estimating the population mean. Several properties of theclass are derived and the results are numerically supported.

  9. The class of n-entire operators

    International Nuclear Information System (INIS)

    We introduce a classification of simple, regular, closed symmetric operators with deficiency indices (1, 1) according to a geometric criterion that extends the classical notions of entire operators and entire operators in the generalized sense due to M G Krein. We show that these classes of operators have several distinctive properties, some of them related to the spectra of their canonical self-adjoint extensions. In particular, we provide necessary and sufficient conditions on the spectra of two canonical self-adjoint extensions of an operator for it to belong to one of our classes. Our discussion is based on some recent results in the theory of de Branges spaces. (paper)

  10. Dosing method of physical activity in aerobics classes for students

    OpenAIRE

    Beliak Yu. I.; Zinchenko N.M.

    2014-01-01

    Purpose : reasons for the method of dosing of physical activity in aerobics classes for students. The basis of the method is the evaluation of the metabolic cost of funds used in them. Material : experiment involved the assessment of the pulse response of students to load complexes classical and step aerobics (n = 47, age 20-23 years). In complexes used various factors regulating the intensity: perform combinations of basic steps, involvement of movements with his hands, holding in hands dumb...

  11. A new class of dynamic quantum metamaterials

    CERN Document Server

    Quach, James Q; Martin, Andrew M; Greentree, Andrew D; Hollenberg, Lloyd C L

    2010-01-01

    Controllable quantum systems are heralding a quantum technology revolution. By coupling controllable quantum systems into larger structures we introduce the concept of a quantum metamaterial. Conventional metamaterials represent one the most important frontiers in optical design, with applications in diverse fields ranging from medicine to aerospace. Up until now however, metamaterials have themselves been classical structures and interact only with the classical properties of light. Here we describe a class of dynamic metamaterials, based on the quantum properties of coupled atom-cavity arrays, which are intrinsically lossless, reconfigurable, and operate fundamentally at the quantum level. We show how this new class of metamaterial could be used to create a reconfigurable quantum superlens possessing a negative index gradient for single photon imaging. With the inherent features of quantum superposition and entanglement of metamaterial properties, this new class of dynamic quantum metamaterial, opens a new ...

  12. Deployment of a class 2 tensegrity boom

    Science.gov (United States)

    Pinaud, Jean-Paul; Solari, Soren; Skelton, Robert E.

    2004-07-01

    Tensegrity structures are special truss structures composed of bars in compression and cables in tension. Most tensegrity structures under investigation, to date, have been of Class 1, where bars do not touch. In this article, however, we demonstrate the hardware implementation of a 2 stage symmetric Class 2 tensegrity structure, where bars do connect to each other at a pivot. The open loop control law for tendon lengths to accomplish the desired geometric reconfiguration are computed analytically. The velocity of the structure's height is chosen and reconfiguration is accomplished in a quasi-static manner, ignoring dynamic effects. The main goal of this research was to design, build, and test the capabilities of the Class 2 structure for deployment concepts and to further explore the possibilities of multiple stage structures using the same design and components.

  13. On a class of topological groups

    Directory of Open Access Journals (Sweden)

    Dinamérico P. Pombo Jr

    2006-11-01

    Full Text Available A topological group is an SNS-group if its identity element possessesa fundamental system of neighborhoods formed by normal subgroups. In this paper we prove the existence of initial SNS-topologies, from which we derive that the class of SNS-groups is closed under the formation of products and projective limits, and we prove the existence of final SNS-topologies, from which we derive that the class of SNS-groups is closed under the formation of free products and inductive limits.

  14. Characteristic classes of quantum principal bundles

    CERN Document Server

    Durdevic, M

    1995-01-01

    A noncommutative-geometric generalization of classical Weil theory of characteristic classes is presented, in the conceptual framework of quantum principal bundles. A particular care is given to the case when the bundle does not admit regular connections. A cohomological description of the domain of the Weil homomorphism is given. Relations between universal characteristic classes for the regular and the general case are analyzed. In analogy with classical geometry, a natural spectral sequence is introduced and investigated. The appropriate counterpart of the Chern character is constructed, for structures admitting regular connections. Illustrative examples and constructions are presented.

  15. Learnable Classes of Categorial Grammars.

    Science.gov (United States)

    Kanazawa, Makoto

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

  16. GOALS OF PARTICIPATION IN PHYSICAL EDUCATION CLASSES

    OpenAIRE

    Rahim Ramzaninezhad; Farhad Rahmaninia; Mehr Ali Hemmatinezhad; Nooshin Benar; Misagh Hoseini Keshtan

    2011-01-01

    The importance of physical education in school life and for health points to the need to the better understands goal's participation of students in school education classes. This study was an attempt to investigate students' goals for participates in physical education (PE) classes. 455 random out of 72673 students of junior and senior high schools with the age range of 11 to 19 years (M=14.67). A 28-items survey was administrated to assess (a) demographics and (b) Purposes for Engaging in Ph...

  17. A Small Special Needs Class or a Smaller Class at the Beginning of the Educational Path?

    OpenAIRE

    Valli, Raine; Jokinen, Katja

    2016-01-01

    This article is based on the case study which focuses on the small class (in this article used to describe a small special needs class) operation of one medium-sized Finnish town. In the study an attempt was made to clarify what kind of alternative the small class is to the first grade of general education at the beginning of the child's educational path, what kind of experiences the teachers had of the pupils of the small class, of multi-vocational cooperation and of pupils' i...

  18. Weak equivalence classes of complex vector bundles

    OpenAIRE

    Hông-Vân Lê

    2006-01-01

    For any complex vector bundle Ek of rank k over a manifold Mm with Chern classes ci Î H2i(Mm, Z) and any non-negative integers l1, . . ., lk we show the existence of a positive number p(m, k) and the existence of a complex vector bundle Êk over Mm whose Chern classes are p(m, k) × li × ci Î H2i(Mm, Z). We also discuss a version of this statement for holomorphic vector bundles over projective algebraic manifolds.

  19. A new class of non-leaves

    CERN Document Server

    Souza, Fábio S

    2011-01-01

    We give examples of open smooth manifolds that cannot be leaves of any Riemannian foliation of arbitrary codimension on a compact manifold. We also present a new class of non-leaves of C^0 codimension one foliations, simply connected manifolds of dimension at least 5 that are non-periodic in homotopy, namely in their 2-dimensional homotopy groups.

  20. System Model Semantics of Class Diagrams

    OpenAIRE

    Cengarle, Maria Victoria; Grönninger, Hans; Rumpe, Bernhard

    2014-01-01

    Defining semantics for UML is a difficult task. Disagreements in the meaning of UML constructs as well as the size of UML are major obstacles. In this report, we describe our approach to define the semantics for UML. Semantics is defined denotationally as a mapping into our semantics domain called the system model [4, 5, 6]. We demonstrate our approach by defining the semantics for a comprehensive version of class diagrams. The semantics definition is detailed for UML/P class diagrams, a vari...

  1. Designing a new class of distributed systems

    CERN Document Server

    Mikkilineni, Rao

    2011-01-01

    Designing a New Class of Distributed Systems closely examines the Distributed Intelligent Managed Element (DIME) Computing Model, a new model for distributed systems, and provides a guide to implementing Distributed Managed Workflows with High Reliability, Availability, Performance and Security. The book also explores the viability of self-optimizing, self-monitoring autonomous DIME-based computing systems. Designing a New Class of Distributed Systems is designed for practitioners as a reference guide for innovative distributed systems design. Researchers working in a related field will also f

  2. Types and classes of insurance

    International Nuclear Information System (INIS)

    The German insurance pool for nuclear risks, the Deutsche Kernreaktor-Versicherungsgemeinschaft (DKVG), currently counts 105 members. In 1987, insurance protection provided for German nuclear power plants amounted to DM 1.5 thousand millions from property insurance, and DM 200 millions from nuclear liability insurance. The major part of financial security comes from the pool members, but some security also is provided by foreign nuclear insurance pools. In return, the DKVG signed a number of insurance policies as a reinsurance for nuclear installations abroad. The statistical survey presents facts and data for 1986 and 1987, and a brief review of 1986 events. The Chernobyl reactor accident did not affect the DKVG financially, as the Soviet nuclear industry does not co-operate in the international system of reinsurance. (orig./HSCH)

  3. Hierarchical Classes Modeling of Rating Data

    Science.gov (United States)

    Van Mechelen, Iven; Lombardi, Luigi; Ceulemans, Eva

    2007-01-01

    Hierarchical classes (HICLAS) models constitute a distinct family of structural models for N-way N-mode data. All members of the family include N simultaneous and linked classifications of the elements of the N modes implied by the data; those classifications are organized in terms of hierarchical, if-then-type relations. Moreover, the models are…

  4. Classes of almost clean rings

    OpenAIRE

    Akalan, Evrim; Vas, Lia

    2013-01-01

    A ring is clean (almost clean) if each of its elements is the sum of a unit (regular element) and an idempotent. A module is clean (almost clean) if its endomorphism ring is clean (almost clean). We show that every quasi-continuous and nonsingular module is almost clean and that every right CS and right nonsingular ring is almost clean. As a corollary, all right strongly semihereditary rings, including finite $AW^*$-algebras and noetherian Leavitt path algebras in particular, are almost clean...

  5. Utilization of Social Media in Marketing Classes

    Science.gov (United States)

    Allen, Charlotte

    2013-01-01

    The goal of this paper is to highlight how instructors may integrate the different social media into various marketing classes. The paper will address the major social networks, and then follow with discussions of microblogging, media sites, and social gaming. Given that there is a great deal of research highlighting the effectiveness of utilizing…

  6. Negotiations of Acknowledgement among Middle Class Residents

    DEFF Research Database (Denmark)

    Andersen, Nina Blom

    2013-01-01

    The article presents an analysis of communication processes between residents, between residents and people in the broader societal context as well as of media coverage of a fireworks disaster in a Danish suburb. It demonstrates how residents (all members of the Danish middle class) were able to...

  7. Non-extraction treatment of skeletal class II malocclusion

    Directory of Open Access Journals (Sweden)

    Abhay K Jain

    2012-01-01

    Full Text Available Introduction: Every orthodontist at some point in his clinical practice has faced the dilemma of how ′best′ to manage a mild to moderate Class II malocclusion. Aims and Objectives: To demonstrate the efficacy of Forsus™ Fatigue Resistant Device in the management of Class II malocclusion. Materials and Method: A patient having Class II division 1 malocclusion with functional jaw retrusion was treated using MBT 0.022" prescription and Forsus FRD appliance. Pre- and post-treatment photographs and lateral cephalograms were taken. Cephalometric analysis was done, and results were superimposed. Result: 7-8 months of Forsus wear obtained stable and successful results with improvement in facial profile, skeletal jaw relationship, and mild increase in IMPA. Discussion and Conclusion: Greater forward displacement of the mandible was the predominant factor for successful treatment Class II patient. Forsus gives good results for class II management, and it would be wise to consider treating such cases by non-extraction approach rather than contemplating extractions.

  8. Dentofacial characteristics of patients with Angle Class I and Class II malocclusions

    Directory of Open Access Journals (Sweden)

    Rogério Lacerda dos Santos

    2012-04-01

    Full Text Available OBJECTIVE: The present study assessed some cephalometric measurements of the soft tissue profile in order to observe the behavior of facial convexity in patients with Class I, Class II division 1, and Class II division 2 malocclusions. METHODS: One hundred and thirty pre-treatment teleradiographs of Caucasian patients aged 10-16 years (mean age of 12.6 years were selected for study and divided into 3 groups. The cephalometric measurements used in the present study were the following: H.SN, Cx, NLA, MLA, UL-SUL-S, LL-S, IMPA, and 1-SN. Analysis of variance and Tukey's test were applied for measurements H.SN, Cx, IMPA, 1-SN, MLA, and NLA, whereas Kruskal-Wallis and Dunn's tests were applied for UL-S and LL-S. RESULTS: The results showed statistically significant differences for the measurements H.SN, Cx, UL-S, and IMPA between Groups I, II-1 and II-2 (p < 0.05. Measurements LL-S and MLA showed statistically significant difference between Groups I and II-1 only (p < 0.05. On the other hand, no statistically significant differences were found for measurement NLA among the 3 groups (p < 0.05. CONCLUSION: Regarding facial characteristics expressed by measurements H.SN, Cx, and UL-S, one could conclude that Class II division 1 and Class II division 2 malocclusions, both differed from Class I malocclusion. In addition, Class II division 1 malocclusion was found to have facial characteristics expressed by MLA, which differentiate it from the Class II division 2 and Class 1 malocclusions. Class I, Class II division 1 and Class II division 2 malocclusions showed no difference in facial characteristics expressed by the measurement NLA, and measurement LL-S was directly related to eversion of the lower lip.

  9. Social Class Experiences of Working-Class Students: Transitioning out of College

    Science.gov (United States)

    Treager Huber, Carey

    2010-01-01

    Issues surrounding social class are often overlooked and rarely discussed in higher education; however, they affect students and institutions in critical ways. Although research has demonstrated that social class is a predictor of access to college, retention, academic performance, overall undergraduate and graduate experience, and college…

  10. Weighted classes of quaternion-valued functions

    OpenAIRE

    A. El-Sayed Ahmed; Omran, Saleh

    2012-01-01

    In this paper, we define the classes $F(p,q,s)$ of quaternion-valued functions, then we characterize quaternion Bloch functions by quaternion $F(p,q,s)$ functions in the unit ball of $\\mathbb{R}^3$. Further, some important basic properties of these functions are also considered.

  11. The Promise of Single-Sex Classes

    Science.gov (United States)

    Stotsky, Sandra

    2012-01-01

    Despite the enthusiasm and the absence of definitive research on the pros and cons of single-sex classes, a 2011 article in Science, titled "The Pseudoscience of Single-Sex Schooling," by a new organization called American Council for CoEducational Schooling (ACCES) came out with the astonishing conclusion that single-sex education is ineffective…

  12. Class in Metropolitan India: The Rise of the Middle Classes

    NARCIS (Netherlands)

    J.E. Mooij (Jos); S.T. Lama-Rewal

    2009-01-01

    textabstractIt is almost a cliché to say that India’s appearance and image (internationally as well as self-image) have changed dramatically in the last fifteen years. Instead of being associated with rural poverty, India is now associated with high rates of economic growth, a booming Information Te

  13. Economies of Scale and Large Classes

    Science.gov (United States)

    Saiz, Martin

    2014-01-01

    Making classes larger saves money--and public universities across the country have found it a useful strategy to balance their budgets after decades of state funding cuts and increases to infrastructure costs. Where this author teaches, in the College of Social and Behavioral Sciences at California State University, Northridge (CSUN),…

  14. In Pursuit of the Working Class

    Directory of Open Access Journals (Sweden)

    Ben Clarke

    2013-08-01

    Full Text Available A review of Owen Jones, Chavs: The Demonization of the Working Class (Verso, 2012, Zygmunt Bauman, Collateral Damage: Social Inequalities in a Global Age (Polity, 2011 and David Nichols, The Bogan Delusion: Myths, Mischief and Misconceptions (Affirm, 2011.

  15. Higher class groups of Eichler orders

    International Nuclear Information System (INIS)

    In this paper, we prove that if A is a quaternion algebra and Λ an Eichler order in A, then the only p-torsion possible in even dimensional higher class groups Cl2n (Λ) (n ≥ 1) are for those rational primes p which lie under prime ideals of OF at which Λ are not maximal. (author)

  16. p-Coloring Classes of Torus Knots

    OpenAIRE

    Breiland, Anna-Lisa; Oesper, Layla; Taalman, Laura

    2009-01-01

    We classify by elementary methods the $p$-colorability of torus knots, and prove that every $p$-colorable torus knot has exactly one nontrivial $p$-coloring class. As a consequence, we note that the two-fold branched cyclic cover of a torus knot complement has cyclic first homology group.

  17. A new class of SUMO proteases

    OpenAIRE

    Gillies, Jennifer; Hochstrasser, Mark

    2012-01-01

    A new class of SUMO protease, DeSUMOylating enzyme (DeSI)—that has different substrates and localization to SENP SUMO proteases—is characterized in this issue of EMBO reports. The implications for the field are discussed here.

  18. Stability of latent class segments over time

    DEFF Research Database (Denmark)

    Mueller, Simone

    2011-01-01

    Dynamic stability, as the degree to which identified segments at a given time remain unchanged over time in terms of number, size and profile, is a desirable segment property which has received limited attention so far. This study addresses the question to what degree latent classes identified from...

  19. The Class of 2011 Student Survey Report

    Science.gov (United States)

    National Association of Colleges and Employers (NJ3), 2011

    2011-01-01

    Based on responses from 20,000 college seniors nationwide, "The Class of 2011 Student Survey Report" gives you hard numbers "plus" the analysis you need to develop your college recruiting strategy and build your brand among college students. Align your recruiting strategies tactics with students' wants, needs, attitudes, and behaviors--you'll get…

  20. 76 FR 68058 - Classes of Poultry

    Science.gov (United States)

    2011-11-03

    .... demand elasticity to be -. 43 for young chickens and - 0.62 for other chickens. Poultry Slaughter and... chicken (roaster or broiler) over the other. In addition, empirical evidence shows that price elasticity... definitions and standards for the official U.S. classes of poultry (68 FR 55902). Before publishing the...

  1. Social Class and Social Action: The Middle-Class Bias of Democratic Theory in Education

    Science.gov (United States)

    Schutz, Aaron

    2008-01-01

    Background: This article examines the emergence of the middle and working classes in America and describes key characteristics of these cultures as they manifest themselves today. It then explores the effects of social class on our conceptions of democracy. Purpose: To help educators understand the relationship between social action strategies and…

  2. Reading in Class & out of Class: An Experience Sampling Method Study

    Science.gov (United States)

    Shumow, Lee; Schmidt, Jennifer A.; Kackar, Hayal

    2008-01-01

    This study described and compared the reading of sixth and eighth grade students both in and out of school using a unique data set collected with the Experience Sampling Method (ESM). On average, students read forty minutes a day out of class and seventeen minutes a day in class indicating that reading is a common leisure practice for…

  3. 25 CFR 522.12 - Revocation of class III gaming.

    Science.gov (United States)

    2010-04-01

    ... 25 Indians 2 2010-04-01 2010-04-01 false Revocation of class III gaming. 522.12 Section 522.12 Indians NATIONAL INDIAN GAMING COMMISSION, DEPARTMENT OF THE INTERIOR APPROVAL OF CLASS II AND CLASS III ORDINANCES AND RESOLUTIONS SUBMISSION OF GAMING ORDINANCE OR RESOLUTION § 522.12 Revocation of class...

  4. Contrasting evolutionary histories of MHC class I and class II loci in grouse—Effects of selection and gene conversion

    Science.gov (United States)

    Minias, Piotr; Bateson, Zachary W; Whittingham, Linda A; Johnson, Jeff A.; Oyler-McCance, Sara J.; Dunn, Peter O

    2016-01-01

    Genes of the major histocompatibility complex (MHC) encode receptor molecules that are responsible for recognition of intracellular and extracellular pathogens (class I and class II genes, respectively) in vertebrates. Given the different roles of class I and II MHC genes, one might expect the strength of selection to differ between these two classes. Different selective pressures may also promote different rates of gene conversion at each class. Despite these predictions, surprisingly few studies have looked at differences between class I and II genes in terms of both selection and gene conversion. Here, we investigated the molecular evolution of MHC class I and II genes in five closely related species of prairie grouse (Centrocercus and Tympanuchus) that possess one class I and two class II loci. We found striking differences in the strength of balancing selection acting on MHC class I versus class II genes. More than half of the putative antigen-binding sites (ABS) of class II were under positive or episodic diversifying selection, compared with only 10% at class I. We also found that gene conversion had a stronger role in shaping the evolution of MHC class II than class I. Overall, the combination of strong positive (balancing) selection and frequent gene conversion has maintained higher diversity of MHC class II than class I in prairie grouse. This is one of the first studies clearly demonstrating that macroevolutionary mechanisms can act differently on genes involved in the immune response against intracellular and extracellular pathogens.

  5. Chemical Compatibility of Polymeric Materials.

    Science.gov (United States)

    Solen, Kenneth A.; Kuchar, Marvin C.

    1990-01-01

    Presents some principles for specifying general classes of polymers for predicting relative chemical attack from acids, bases, oxidants, and certain common antagonists. Also discusses predicting relative solvent effects. Suggests uses of this information in two or three lectures in a chemical engineering materials course. (YP)

  6. Structural Properties of MHC Class II Ligands, Implications for the Prediction of MHC Class II Epitopes

    DEFF Research Database (Denmark)

    Jørgensen, Kasper Winther; Buus, Søren; Nielsen, Morten

    2010-01-01

    properties of MHC class II ligands. Here, we perform one such large-scale analysis. A large set of SYFPEITHI MHC class II ligands covering more than 20 different HLA-DR molecules was analyzed in terms of their secondary structure and surface exposure characteristics in the context of the native structure of...... the corresponding source protein. We demonstrated that MHC class II ligands are significantly more exposed and have significantly more coil content than other peptides in the same protein with similar predicted binding affinity. We next exploited this observation to derive an improved prediction...

  7. Small-Space Analogues of Valiant's Classes

    Science.gov (United States)

    Mahajan, Meena; Rao, B. V. Raghavendra

    In the uniform circuit model of computation, the width of a boolean circuit exactly characterises the “space” complexity of the computed function. Looking for a similar relationship in Valiant’s algebraic model of computation, we propose width of an arithmetic circuit as a possible measure of space. We introduce the class VL as an algebraic variant of deterministic log-space L. In the uniform setting, we show that our definition coincides with that of VPSPACE at polynomial width.

  8. Thoughts on the Role of Government in the Development of World-Class Universities in China

    Science.gov (United States)

    Guangcai, Yan

    2011-01-01

    Looking at the rise of world-class universities through history, creating an institutional environment in which universities are relatively autonomous, while also ensuring effective material support from the government is essential for the formation of world-class universities. It is worth examining the deteriorating academic environment in China…

  9. A Maximal Tractable Class of Soft Constraints

    CERN Document Server

    Cohen, D; Jeavons, P; Krokhin, A; 10.1613/jair.1400

    2011-01-01

    Many researchers in artificial intelligence are beginning to explore the use of soft constraints to express a set of (possibly conflicting) problem requirements. A soft constraint is a function defined on a collection of variables which associates some measure of desirability with each possible combination of values for those variables. However, the crucial question of the computational complexity of finding the optimal solution to a collection of soft constraints has so far received very little attention. In this paper we identify a class of soft binary constraints for which the problem of finding the optimal solution is tractable. In other words, we show that for any given set of such constraints, there exists a polynomial time algorithm to determine the assignment having the best overall combined measure of desirability. This tractable class includes many commonly-occurring soft constraints, such as 'as near as possible' or 'as soon as possible after', as well as crisp constraints such as 'greater than'. F...

  10. Singularity Classes of Special 2-Flags

    OpenAIRE

    Piotr Mormul

    2009-01-01

    In the paper we discuss certain classes of vector distributions in the tangent bundles to manifolds, obtained by series of applications of the so-called generalized Cartan prolongations (gCp). The classical Cartan prolongations deal with rank-2 distributions and are responsible for the appearance of the Goursat distributions. Similarly, the so-called special multi-flags are generated in the result of successive applications of gCp's. Singularities of such distributions turn out to be very ric...

  11. Transportation of Hazardous Evidentiary Material.

    Energy Technology Data Exchange (ETDEWEB)

    Osborn, Douglas.

    2005-06-01

    This document describes the specimen and transportation containers currently available for use with hazardous and infectious materials. A detailed comparison of advantages, disadvantages, and costs of the different technologies is included. Short- and long-term recommendations are also provided.3 DraftDraftDraftExecutive SummaryThe Federal Bureau of Investigation's Hazardous Materials Response Unit currently has hazardous material transport containers for shipping 1-quart paint cans and small amounts of contaminated forensic evidence, but the containers may not be able to maintain their integrity under accident conditions or for some types of hazardous materials. This report provides guidance and recommendations on the availability of packages for the safe and secure transport of evidence consisting of or contaminated with hazardous chemicals or infectious materials. Only non-bulk containers were considered because these are appropriate for transport on small aircraft. This report will addresses packaging and transportation concerns for Hazardous Classes 3, 4, 5, 6, 8, and 9 materials. If the evidence is known or suspected of belonging to one of these Hazardous Classes, it must be packaged in accordance with the provisions of 49 CFR Part 173. The anthrax scare of several years ago, and less well publicized incidents involving unknown and uncharacterized substances, has required that suspicious substances be sent to appropriate analytical laboratories for analysis and characterization. Transportation of potentially hazardous or infectious material to an appropriate analytical laboratory requires transport containers that maintain both the biological and chemical integrity of the substance in question. As a rule, only relatively small quantities will be available for analysis. Appropriate transportation packaging is needed that will maintain the integrity of the substance, will not allow biological alteration, will not react chemically with the substance being

  12. Demographic Characteristics of World Class Jamaican Sprinters

    OpenAIRE

    Rachael Irving; Vilma Charlton; Errol Morrison; Aldeam Facey; Oral Buchanan

    2013-01-01

    The dominance of Jamaican sprinters in international meets remains largely unexplained. Proposed explanations include demographics and favorable physiological characteristics. The aim of this study was to analyze the demographic characteristics of world class Jamaican sprinters. Questionnaires administered to 120 members of the Jamaican national team and 125 controls elicited information on place of birth, language, ethnicity, and distance and method of travel to school. Athletes were divided...

  13. On some classes of bipartite unitary operators

    Science.gov (United States)

    Deschamps, Julien; Nechita, Ion; Pellegrini, Clément

    2016-08-01

    We investigate unitary operators acting on a tensor product space, with the property that the quantum channels they generate, via the Stinespring dilation theorem, are of a particular type, independently of the state of the ancilla system in the Stinespring relation. The types of quantum channels we consider are those of interest in quantum information theory: unitary conjugations, constant channels, unital channels, mixed unitary channels, positive partial transpose channels, and entanglement breaking channels. For some of the classes of bipartite unitary operators corresponding to the above types of channels, we provide explicit characterizations, necessary and/or sufficient conditions for membership, and we compute the dimension of the corresponding algebraic variety. Inclusions between these classes are considered, and we show that for small dimensions, many of these sets are identical.

  14. The Effect of Mixed-Age Classes in Sweden

    Science.gov (United States)

    Lindstrom, Elly-Ann; Lindahl, Erica

    2011-01-01

    Mixed-aged (MA) classes are a common phenomenon around the world. In Sweden, these types of classes increased rapidly during the 1980s and 1990s, despite the fact that existing empirical support for MA classes is weak. In this paper, the effect of attending an MA class during grades 4-6 on students' cognitive skills is estimated. Using a unique…

  15. Classes of graphs with restricted interval models

    Directory of Open Access Journals (Sweden)

    Andrzej Proskurowski

    1999-12-01

    Full Text Available We introduce q-proper interval graphs as interval graphs with interval models in which no interval is properly contained in more than q other intervals, and also provide a forbidden induced subgraph characterization of this class of graphs. We initiate a graph-theoretic study of subgraphs of q-proper interval graphs with maximum clique size k+1 and give an equivalent characterization of these graphs by restricted path-decomposition. By allowing the parameter q to vary from 0 to k, we obtain a nested hierarchy of graph families, from graphs of bandwidth at most k to graphs of pathwidth at most k. Allowing both parameters to vary, we have an infinite lattice of graph classes ordered by containment.

  16. Polarity for a Class of Levy Processes

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Polar set of Markov processes is an important concept in probabilistic potential theory, but it is not easy to judge the polarity of the sets. In this paper, we give some results which can be easily used to examine the polarity of the sets when Xt belongs to a special class of Levy processes. We also give a result about polar functions of symmetric stable processes.

  17. A class of singularly perturbed evolution systems

    Directory of Open Access Journals (Sweden)

    N. U. Ahmed

    1994-01-01

    Full Text Available In this paper we study a class of evolution equations where the semigroup generators are singularly perturbed by a nonnegative real valued function of time. Sufficient conditions for existence of evolution operators and their compactness are given including continuous dependence on the perturbation. Further, for a coupled system of singularly perturbed semilinear systems in two Banach spaces, existence of periodic solutions and their stability are studied.

  18. Catastrophic models of materials destruction

    Science.gov (United States)

    Kupchishin, A. I.; Taipova, B. G.; Kupchishin, A. A.; Voronova, N. A.; Kirdyashkin, V. I.; Fursa, T. V.

    2016-02-01

    The effect of concentration and type of fillers on mechanical properties of composite material based on polyimide were studied. Polyethylene terephthalate (PET, polyester), polycarbonate (PCAR) and montmorillonite (MM) were used as the fillers. The samples were prepared by mechanically blending the polyimide-based lacquer solutions with different concentrations of the second component. The concentration of filler and its class, especially their internal structure and technology of synthesis determine features of physical and mechanical properties of obtained materials. Models of catastrophic failure of material satisfactorily describe the main features depending on tension ct from deformation e.

  19. Perception of classroom climate in gym classes

    Directory of Open Access Journals (Sweden)

    Vlasta Zabukovec

    2001-09-01

    Full Text Available This presentation is a part of larger study among Slovene primary and secondary students and their sports' teachers, related to their attitude to gym classes. In this part the results of perception of classroom climate among students will be presented. In the research, 1152 students were participated; they were from fifth and seventh grade from primary school and first and third grade form secondary school. The questionnaire Classroom climate in sport classes was applied (actual and preferred form, which included seven dimensions: satisfaction, competitiveness, methods, students' activity, difficulty, adequateness and personal relationship. Results confirmed the changes in perception of classroom climate; they decreased form fifth grade of primary school to third grade of secondary school. The changes were more extensive in primary school, from primary to secondary school and became stable in secondary school. The differences in perception of classroom climate between boys and girls were confirmed, too.

  20. Stochastic blockmodels with growing number of classes

    CERN Document Server

    Choi, David S; Airoldi, Edoardo M

    2010-01-01

    We present asymptotic and finite-sample results on the use of single-membership stochastic blockmodels for the analysis of network data. We show that the fraction of misclassified network nodes converges in probability to zero under maximum likelihood fitting when the number of classes is allowed to grow as the root of the network size and the average network degree grows at least poly-logarithmically in this size. We also establish finite-sample confidence bounds on maximum-likelihood blockmodel parameter estimates from data comprising independent Bernoulli random variates; these results hold uniformly over class assignment. We provide simulations verifying the conditions sufficient for our results, and conclude by fitting a logit parameterization of a stochastic blockmodel with covariates to a network data example comprising a collection of Facebook profiles, resulting in block estimates that reveal residual structure.

  1. Universality Classes in Folding Times of Proteins

    Science.gov (United States)

    Cieplak, Marek; Hoang, Trinh Xuan

    2003-01-01

    Molecular dynamics simulations in simplified models allow one to study the scaling properties of folding times for many proteins together under a controlled setting. We consider three variants of the Go models with different contact potentials and demonstrate scaling described by power laws and no correlation with the relative contact order parameter. We demonstrate existence of at least three kinetic universality classes that are correlated with the types of structure: the α-, α-β-, and β- proteins have the scaling exponents of ∼1.7, 2.5, and 3.2, respectively. The three classes merge into one when the contact range is truncated at a reasonable value. We elucidate the role of the potential associated with the chirality of a protein. PMID:12524300

  2. 49 CFR 173.427 - Transport requirements for low specific activity (LSA) Class 7 (radioactive) materials and...

    Science.gov (United States)

    2010-10-01

    ... this section must be packaged in accordance with 10 CFR part 71. (e) Tables 5 and 6 are as follows... 49 Transportation 2 2010-10-01 2010-10-01 false Transport requirements for low specific activity... SHIPMENTS AND PACKAGINGS Class 7 (Radioactive) Materials § 173.427 Transport requirements for low...

  3. Lattices of Schunck Classes of Finite Universal Algebras

    Institute of Scientific and Technical Information of China (English)

    Wenbin Guo; K.P. Shum

    2003-01-01

    We prove that the set of all Schunck classes of Mal'cev algebras satisfying the maximum condition for subalgebras is a distributive lattice and its sublattice consisting of all Schunck classes of finite algebras is algebraic. This generalizes many results in the literature on Schunck classes. We also obtain some equivalent conditions for a class of algebras to be a Schunck class and investigate the structure of the class (algebras A |τ(A) = {A}), where τ is a subsystem functor.2000 Mathematics Subject Classification: 08A05, 08B05

  4. Universality classes in folding times of proteins

    OpenAIRE

    Cieplak, Marek; Hoang, Trinh Xuan

    2002-01-01

    Molecular dynamics simulations in simplified models allow one to study the scaling properties of folding times for many proteins together under a controlled setting. We consider three variants of the Go models with different contact potentials and demonstrate scaling described by power laws and no correlation with the relative contact order parameter. We demonstrate existence of at least three kinetic universality classes which are correlated with the types of structure: the alpha-, alpha--be...

  5. Rational design of class I MHC ligands

    Science.gov (United States)

    Rognan, D.; Scapozza, L.; Folkers, G.; Daser, Angelika

    1995-04-01

    From the knowledge of the three-dimensional structure of a class I MHC protein, several non natural peptides were designed in order to either optimize the interactions of one secondary anchor amino acid with its HLA binding pocket or to substitute the non interacting part with spacer residues. All peptides were synthesized and tested for binding to the class I MHC protein in an in vitro reconstitution assay. As predicted, the non natural peptides present an enhanced binding to the HLA-B27 molecule with respect to their natural parent peptides. This study constitutes the first step towards the rational design of non peptidic MHC ligands that should be very promising tools for the selective immunotherapy of autoimmune diseases.

  6. Dimensions of a class of high-dimensional homogeneous Moran sets and Moran classes

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A class of high-dimensional homogeneous Moran sets and Moran classes are introduced and some dimensional properties are studied. The Hausdorff dimension, modified lower box-counting dimension, lower and upper box-counting dimension, and packing dimension of high-dimensional homogeneous and partial homogeneous Cantor sets are determined. Moreover, a kind of fractal E is obtained, which is not regular but with the property Dimw(Ed)=dDimw(E), where w denotes any of the dimensions mentioned above.

  7. Liquidity constraints of the middle class

    OpenAIRE

    Campbell, J.R.; Hercowitz, Zvi

    2009-01-01

    Consumption of households with liquid financial assets responds much more to transitory income shocks than the permanent-income hypothesis predicts. That is, middle class households act as if they face liquidity constraints. This paper addresses this puzzling observation with a model of impatient households that face a large recurring expenditure. In spite of impatience, they save as this expenditure draws near. We call such saving made in preparation for a foreseeable event "term saving". Un...

  8. Another Class of Perfect Nonlinear Polynomial Functions

    Directory of Open Access Journals (Sweden)

    Menglong Su

    2013-01-01

    Full Text Available Perfect nonlinear (PN functions have been an interesting subject of study for a long time and have applications in coding theory, cryptography, combinatorial designs, and so on. In this paper, the planarity of the trinomials xpk+1+ux2+vx2pk over GF(p2k are presented. This class of PN functions are all EA-equivalent to x2.

  9. Determination of the Universality Class of Gadolinium

    International Nuclear Information System (INIS)

    We resolve a long-standing puzzle for the static and dynamic critical behavior of gadolinium by a combined theoretical and experimental investigation. It is shown that the spin dynamics of a ferromagnet with hcp lattice structure and a spin-spin interaction given by both exchange and dipole-dipole interaction belongs to a new dynamic universality class, model J* . Comparing results from mode coupling theory with results from three different hyperfine interaction probes we find quantitative agreement. copyright 1997 The American Physical Society

  10. A class of Sudan-decodable codes

    DEFF Research Database (Denmark)

    Nielsen, Rasmus Refslund

    2000-01-01

    In this article, Sudan's algorithm is modified into an efficient method to list-decode a class of codes which can be seen as a generalization of Reed-Solomon codes. The algorithm is specialized into a very efficient method for unique decoding. The code construction can be generalized based on...... algebraic-geometry codes and the decoding algorithms are generalized accordingly. Comparisons with Reed-Solomon and Hermitian codes are made....

  11. THE WORKING CLASS, THE EMERGENCE OF THE CLASS CONSCIOUSNESS AND EDUCATION

    Directory of Open Access Journals (Sweden)

    Paulino José Orso

    2011-12-01

    Full Text Available This article deals with the class society, the emergence of the working class, its recognition as such and the education. Starts with a brief discussion of the positivist and materialist conceptions of society and historical dialectics, following, discusses the tests made by the working class in its long history to win his consciousness to another. If, from ancient times we live in a class society, this period is not the consciousness of belonging to a class of workers and much less for an action based on and consistent with this membership. This achievement goes through several times and struggles, whether against the nobility and aristocracy or against the bourgeoisie, who rub shoulders with many struggles to overthrow the forces of the Old Regime. However, these struggles the working class was also realizing that if the bourgeoisie, at various times, was interested in making alliances incidental to the conquest of power, definitely had no interest in sharing it. Thus, in the successive struggles and betrayals of the bourgeoisie, the working class was learning not only not believe in the promises and illusions of his former "comrades", but also claim the right to give the direction of their lives and "their destination".

  12. Novelty Detection in MultiClass Scenarios with Incomplete Set of Class Labels

    OpenAIRE

    Vinokurov, Nomi; Weinshall, Daphna

    2016-01-01

    We address the problem of novelty detection in multiclass scenarios where some class labels are missing from the training set. Our method is based on the initial assignment of confidence values, which measure the affinity between a new test point and each known class. We first compare the values of the two top elements in this vector of confidence values. In the heart of our method lies the training of an ensemble of classifiers, each trained to discriminate known from novel classes based on ...

  13. SMA Observations of Class 0 Protostars

    DEFF Research Database (Denmark)

    Chen, Xuepeng; Arce, Héctor G.; Zhang, Qizhou;

    2013-01-01

    We present high angular resolution 1.3 mm and 850 μm dust continuum data obtained with the Submillimeter Array toward 33 Class 0 protostars in nearby clouds (distance <500 pc), which represents so far the largest survey toward protostellar binary/multiple systems. The median angular resolution in...... the survey is 2.''5, while the median linear resolution is approximately 600 AU. Compact dust continuum emission is observed from all sources in the sample. Twenty-one sources in the sample show signatures of binarity/multiplicity, with separations ranging from 50 AU to 5000 AU. The numbers of singles......, binaries, triples, and quadruples in the sample are 12, 14, 5, and 2, respectively. The derived multiplicity frequency (MF) and companion star fraction (CSF) for Class 0 protostars are 0.64 ± 0.08 and 0.91 ± 0.05, respectively, with no correction for completeness. The derived MF and CSF in this survey are...

  14. The Complexity of Identifying Large Equivalence Classes

    DEFF Research Database (Denmark)

    Skyum, Sven; Frandsen, Gudmund Skovbjerg; Miltersen, Peter Bro;

    1999-01-01

    We prove that at least 3k−4/k(2k−3)(n/2) – O(k)equivalence tests and no more than 2/k (n/2) + O(n) equivalence tests are needed in the worst case to identify the equivalence classes with at least k members in set of n elements. The upper bound is an improvement by a factor 2 compared to known res...

  15. CONSTRUCTION OF A NEW CLASS OF ORTHOGONAL ARRAYS

    Institute of Scientific and Technical Information of China (English)

    Shanqi PANG

    2007-01-01

    By using the generalized Hadamard product, difference matrix and projection matrices, we present a class of orthogonal projection matrices and related orthogonal arrays of strength two. A new class of orthogonal arrays are constructed.

  16. Working Class Mothers and School Life: Exploring the Role of Emotional Capital

    Science.gov (United States)

    Gillies, Val

    2006-01-01

    This paper explores the emotional resources generated by working class mothers to support their children at school. Analysis of material from qualitative interview research with a range working class mothers will focus on specific accounts of children's school lives to reveal how situated meanings can clash with institutional expectations. By…

  17. Dentofacial characteristics of patients with Angle Class I and Class II malocclusions

    OpenAIRE

    Rogério Lacerda dos Santos; Antônio Carlos de Oliveira Ruellas

    2012-01-01

    OBJECTIVE: The present study assessed some cephalometric measurements of the soft tissue profile in order to observe the behavior of facial convexity in patients with Class I, Class II division 1, and Class II division 2 malocclusions. METHODS: One hundred and thirty pre-treatment teleradiographs of Caucasian patients aged 10-16 years (mean age of 12.6 years) were selected for study and divided into 3 groups. The cephalometric measurements used in the present study were the following: H.SN, C...

  18. A study of long term ageing effects in A533B Class 1 and A508 Class 3 steels

    International Nuclear Information System (INIS)

    The effects of long term thermal ageing treatments on notched impact fracture properties has been studied in two commercially produced PWR pressure vessel steels, A533B Class 1 and A508 Class 3. Heat treatments of up to 10,000h duration at temperatures between 300 and 6000C have been investigated. Additionally the effects of specimen size, specimen orientation, specimen position from within the plate and the effect of a prior post weld heat treatment on subsequent fracture behaviour following thermal ageing have been evaluated for the A533B Class 1 material. The susceptibility of both materials to temper embrittlement effects is relatively low, the maximum increase in transition temperature following thermal ageing treatments in the temperature range 300 to 5000C being about 40 to 450C. Thermal ageing at 6000C for times in excess of 100h produces microstructural changes resulting in larger increases in transition temperature. For the A533B material, specimen position and orientation are found to have a large influence on impact behaviour but do not affect the susceptibility to temper embrittlement. Post weld heat treatment has little or no influence on impact fracture behaviour before further isothermal ageing treatments nor on susceptibility to temper embrittlement. (author)

  19. Qualitative Analysis of Animation versus Reading for Pre-Class Preparation in a "Flipped" Classroom

    Science.gov (United States)

    Persky, Adam M.

    2015-01-01

    The "flipped" classroom model, including such approaches as team-based learning (TBL), stresses pre-class preparation. For three years in a pharmacokinetics course within a pharmacy curriculum, students had the choice of using reading material or a fully animated module to prepare for class. Qualitative methods were used to analyze…

  20. Automatic Segmentation of Eight Tissue Classes in Neonatal Brain MRI

    Science.gov (United States)

    Anbeek, Petronella; Išgum, Ivana; van Kooij, Britt J. M.; Mol, Christian P.; Kersbergen, Karina J.; Groenendaal, Floris; Viergever, Max A.; de Vries, Linda S.; Benders, Manon J. N. L.

    2013-01-01

    Purpose Volumetric measurements of neonatal brain tissues may be used as a biomarker for later neurodevelopmental outcome. We propose an automatic method for probabilistic brain segmentation in neonatal MRIs. Materials and Methods In an IRB-approved study axial T1- and T2-weighted MR images were acquired at term-equivalent age for a preterm cohort of 108 neonates. A method for automatic probabilistic segmentation of the images into eight cerebral tissue classes was developed: cortical and central grey matter, unmyelinated and myelinated white matter, cerebrospinal fluid in the ventricles and in the extra cerebral space, brainstem and cerebellum. Segmentation is based on supervised pixel classification using intensity values and spatial positions of the image voxels. The method was trained and evaluated using leave-one-out experiments on seven images, for which an expert had set a reference standard manually. Subsequently, the method was applied to the remaining 101 scans, and the resulting segmentations were evaluated visually by three experts. Finally, volumes of the eight segmented tissue classes were determined for each patient. Results The Dice similarity coefficients of the segmented tissue classes, except myelinated white matter, ranged from 0.75 to 0.92. Myelinated white matter was difficult to segment and the achieved Dice coefficient was 0.47. Visual analysis of the results demonstrated accurate segmentations of the eight tissue classes. The probabilistic segmentation method produced volumes that compared favorably with the reference standard. Conclusion The proposed method provides accurate segmentation of neonatal brain MR images into all given tissue classes, except myelinated white matter. This is the one of the first methods that distinguishes cerebrospinal fluid in the ventricles from cerebrospinal fluid in the extracerebral space. This method might be helpful in predicting neurodevelopmental outcome and useful for evaluating neuroprotective clinical

  1. Automatic segmentation of eight tissue classes in neonatal brain MRI.

    Directory of Open Access Journals (Sweden)

    Petronella Anbeek

    Full Text Available PURPOSE: Volumetric measurements of neonatal brain tissues may be used as a biomarker for later neurodevelopmental outcome. We propose an automatic method for probabilistic brain segmentation in neonatal MRIs. MATERIALS AND METHODS: In an IRB-approved study axial T1- and T2-weighted MR images were acquired at term-equivalent age for a preterm cohort of 108 neonates. A method for automatic probabilistic segmentation of the images into eight cerebral tissue classes was developed: cortical and central grey matter, unmyelinated and myelinated white matter, cerebrospinal fluid in the ventricles and in the extra cerebral space, brainstem and cerebellum. Segmentation is based on supervised pixel classification using intensity values and spatial positions of the image voxels. The method was trained and evaluated using leave-one-out experiments on seven images, for which an expert had set a reference standard manually. Subsequently, the method was applied to the remaining 101 scans, and the resulting segmentations were evaluated visually by three experts. Finally, volumes of the eight segmented tissue classes were determined for each patient. RESULTS: The Dice similarity coefficients of the segmented tissue classes, except myelinated white matter, ranged from 0.75 to 0.92. Myelinated white matter was difficult to segment and the achieved Dice coefficient was 0.47. Visual analysis of the results demonstrated accurate segmentations of the eight tissue classes. The probabilistic segmentation method produced volumes that compared favorably with the reference standard. CONCLUSION: The proposed method provides accurate segmentation of neonatal brain MR images into all given tissue classes, except myelinated white matter. This is the one of the first methods that distinguishes cerebrospinal fluid in the ventricles from cerebrospinal fluid in the extracerebral space. This method might be helpful in predicting neurodevelopmental outcome and useful for evaluating

  2. GOALS OF PARTICIPATION IN PHYSICAL EDUCATION CLASSES

    Directory of Open Access Journals (Sweden)

    Rahim Ramzaninezhad

    2011-07-01

    Full Text Available The importance of physical education in school life and for health points to the need to the better understands goal's participation of students in school education classes. This study was an attempt to investigate students' goals for participates in physical education (PE classes. 455 random out of 72673 students of junior and senior high schools with the age range of 11 to 19 years (M=14.67. A 28-items survey was administrated to assess (a demographics and (b Purposes for Engaging in Physical Activity (PEPAS, on a 5-point Likert scale [23]. A panel of experts (n=10 reviewed the translated from of survey and provided feedback and comments on content validity of the instrument, and 50 student participated in pilot study. The analysis of the result indicated that the Individual development (the physiological efficiency and Psychic equilibrium was rated the highest goal of participating in physical activity followed by the social interaction (the group interaction and cultural involvement and the environmental coping (the spatial orientation and object manipulation. One-way Tukeys' post hoc comparison revealed significant difference between groups of subject differentiated on the basis gender age, Junior/senior high school, physical activity out of school, school team member ships, and physical activity on summer & holidays as Independent factors. The multivariate effect of these factors on some of the student's purpose was significant. The unvaried analyses showed that these factors had a significant effect on some of goals. These findings indicate the importance of ranking of students' purposes for engaging in PE classes. It is also necessary that these goals to be considered by the parents & teachers point of view.

  3. On a Class of Generalized Sampling Functions

    Institute of Scientific and Technical Information of China (English)

    Yi Wang

    2014-01-01

    In this note, we discuss a class of so-called generalized sampling functions. These functions are defined to be the inverse Fourier transform of a family of piece-wise constant functions that are either square integrable or Lebegue integrable on the real number line. They are in fact the generalization of the classic sinc function. Two approaches of constructing the generalized sampling functions are reviewed. Their properties such as cardinality, orthogonality, and decaying properties are discussed. The interactions of those functions and Hilbert transformer are also discussed.

  4. Material deprivation or minimal education? Social class and crime in an egalitarian welfare state.

    Science.gov (United States)

    Savolainen, Jukka; Paananen, Reija; Merikukka, Marko; Aaltonen, Mikko; Gissler, Mika

    2013-09-01

    Research on social class and crime is dominated by perspectives that assume socioeconomic disadvantage to exert causal influence on offending. As an alternative approach, the present study examined hypotheses derived from a social selection perspective which treats intergenerational continuity in antisocial propensity as the primary source of socioeconomic differences in criminal activity. Under this theory, individual characteristics of the parents influence their personal socioeconomic attainment as well as the behavioral traits they pass on to their children. Consistent with both of these perspectives, longitudinal data tracking Finnish males born in 1987 (n=21,513) showed strong negative associations between family socioeconomic status (SES) and offspring rates of criminal offending. In critical support for the selection perspective: (1) these association were linear rather than discrete, (2) parents' educational attainment accounted for most of the association between the occupational measure of family SES and crime, and (3) measures of offspring criminal propensity mediated a substantial share of these effects. Adolescent educational marginalization emerged as the key factor linking childhood socioeconomic status to the risk of criminal offending in emerging adulthood. We discuss the implications of this finding for social influence and social selection models of explanation. PMID:24796557

  5. One class of single negative acoustic metamaterials

    Science.gov (United States)

    Grekova, E. F.

    2015-05-01

    We consider linear elastic complex media the point-body motion of which is described by two vectorial generalized coordinates and the elastic energy contains a term coupling them. All constraints are holonomic and ideal. The dynamics of this continuum is determined by modified Lagrange equations. We specify a class of media whose strain energy depends only on one of the vectorial generalized coordinates, but does not depend on its gradient. We call this generalized coordinate "special." On the partial frequency of the special generalized coordinates under some conditions for the inertial and elastic characteristics, the medium behaves as a system of independent harmonic oscillators, and under other conditions, only the trivial solution exists. It is shown that independently of the nature of generalized coordinates, if the inertial and elastic tensors satisfy certain requirements, there exists a band gap of frequencies for most of the dispersion curves; i.e., the medium is a single negative acoustic metamaterial in this band of frequencies. The partial frequency of the "special" coordinate limits the band gap. For a specific class of parameters, apart from this, there exists a decreasing part of the dispersion curve; i.e., the medium is also a double negative acoustic metamaterial in a certain domain of frequencies.

  6. A class of amplitude modulating and invisible inhomogeneous media

    CERN Document Server

    Vial, Benjamin; Horsley, Simon A R; Philbin, Thomas G; Hao, Yang

    2016-01-01

    We propose a general method to arbitrarily manipulate the amplitude of an electromagnetic wave propagating in a two-dimensional medium, without introducing any scattering. This leads to a whole class of isotropic spatially varying permittivity and permeability profiles that are invisible while shaping the field magnitude. In addition, we propose a metamaterial structure working in the infrared that demonstrates deep sub-wavelength control of the electric field amplitude and strong reduction of the scattering. This work offers an alternative strategy to achieve invisibility with isotropic materials and paves the way for tailoring the propagation of light at the nanoscale.

  7. DYNAMICS IN A CLASS OF NEURON MODELS

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    In this paper, we investigate the dynamics in a class of discrete-time neuron mod-els. The neuron model we discussed, defined by such periodic input-output mapping as a sinusoidal function, has a remarkably larger memory capacity than the conven-tional association system with the monotonous function. Our results show that the orbit of the model takes a conventional bifurcation route, from stable equilibrium, to periodicity, even to chaotic region. And the theoretical analysis is verified by numerical simula...

  8. DYNAMICS IN A CLASS OF NEURON MODELS

    Institute of Scientific and Technical Information of China (English)

    Wang Junping; Ruan Jiong

    2009-01-01

    In this paper, we investigate the dynamics in a class of discrete-time neuron mo-dels. The neuron model we discussed, defined by such periodic input-output mapping as a sinusoidal function, has a remarkably larger memory capacity than the conven-tional association system with the monotonous function. Our results show that the orbit of the model takes a conventional bifurcation route, from stable equilibrium, to periodicity, even to chaotic region. And the theoretical analysis is verified by numerical simulations.

  9. On the Structure of Valiant's Complexity Classes

    Directory of Open Access Journals (Sweden)

    Peter Bürgisser

    1999-12-01

    Full Text Available In Valiant developed an algebraic analogue of the theory of NP-completeness for computations of polynomials over a field. We further develop this theory in the spirit of structural complexity and obtain analogues of well-known results by Baker, Gill, and Solovay, Ladner, and Schöning. We show that if Valiant's hypothesis is true, then there is a p-definable family, which is neither p-computable nor VNP-complete. More generally, we define the posets of p-degrees and c-degrees of p-definable families and prove that any countable poset can be embedded in either of them, provided Valiant's hypothesis is true. Moreover, we establish the existence of minimal pairs for VPin VNP. Over finite fields, we give a specific example of a family of polynomials which is neither VNP-complete nor p-computable, provided the polynomial hierarchy does not collapse. We define relativized complexity classes VP h and VNP h and construct complete families in these classes. Moreover, we prove that there is a p-family h satisfying VP h = VNP h.

  10. Material models of dark energy.

    OpenAIRE

    Pearson, Jonathan A.

    2014-01-01

    A new class of “dark energy” models is reviewed and developed, in which the relativistic theory of solids is used to construct material models of dark energy. These are models which include the effects of a continuous medium with well defined physical properties at the level of linearized perturbations. The formalism is constructed for a medium with arbitrary symmetry, and then specialised to isotropic media (which will be the case of interest for the majority of cosmological applications). T...

  11. Four classes of interactions for evolutionary games

    Science.gov (United States)

    Szabó, György; Bodó, Kinga S.; Allen, Benjamin; Nowak, Martin A.

    2015-08-01

    The symmetric four-strategy games are decomposed into a linear combination of 16 basis games represented by orthogonal matrices. Among these basis games four classes can be distinguished as it is already found for the three-strategy games. The games with self-dependent (cross-dependent) payoffs are characterized by matrices consisting of uniform rows (columns). Six of 16 basis games describe coordination-type interactions among the strategy pairs and three basis games span the parameter space of the cyclic components that are analogous to the rock-paper-scissors games. In the absence of cyclic components the game is a potential game and the potential matrix is evaluated. The main features of the four classes of games are discussed separately and we illustrate some characteristic strategy distributions on a square lattice in the low noise limit if logit rule controls the strategy evolution. Analysis of the general properties indicates similar types of interactions at larger number of strategies for the symmetric matrix games.

  12. The rise of middle class in rural China

    OpenAIRE

    Zhang Yuan; Guanghua Wan; Niny Khor

    2012-01-01

    Purpose – Using official and household survey data, the purpose of this paper is to analyze the size of middle class in rural China, its trend and geographical distribution. Determinants or drivers of changes in the size of middle class are explored. Design/methodology/approach – An absolute definition of middle class, adjusted by rural purchasing power parity (PPP) and spatial price index, is employed to measure the size and geographic distribution of rural middle class in 1988, 1995, 2002, ...

  13. Morita equivalence and characteristic classes of star products

    CERN Document Server

    Bursztyn, H; Waldmann, S

    2009-01-01

    This paper deals with two aspects of the theory of characteristic classes of star products: first, on an arbitrary Poisson manifold, we describe Morita equivalent star products in terms of their Kontsevich classes; second, on symplectic manifolds, we describe the relationship between Kontsevich's and Fedosov's characteristic classes of star products.

  14. Evolução dos preparos das cavidades de classe II Developments in preparation of class II cavities

    Directory of Open Access Journals (Sweden)

    Mary Miyuki ONO

    1997-01-01

    Full Text Available A evolução dos preparos de classe II com a introdução de novos materiais e a conscientização da importância da preservação de estrutura dental sadia são abordadas nos preparos do tipo Almqvist, Roggenkamp e túnel, em que se observa a necessidade de menor desgaste da estrutura dentária, com aumento da resistência à fratura, melhor estética e melhor retençãoDevelopments in preparation of class II cavities with the introduction of new materials and awareness of the importance of preservation of a sound dental structure are broached in preparations of the type Almqvist, Roggenkamp and tunnel, where the need for less wear of the dental structure was observed with an increase in fracture strength, better aesthetics, and better retention

  15. Nobility and Stupidity: Modeling the Evolution of Class Endogamy

    OpenAIRE

    Belding, Theodore C.

    2004-01-01

    Class endogamy is a phenomenon in which nobles only marry other nobles and commoners only marry other commoners. The origin of class endogamy, and of social stratification in general, is a major open question in archaeology. This paper implements a verbal model proposed by Marcus and Flannery as a class of agent-based computer models by generalizing and simplifying a mathematical model of marriage markets developed by Burdett and Coles. One force that can produce class endogamy occurs if agen...

  16. Analysis of Asset Classes Through the Business Cycle

    OpenAIRE

    Audrius Dzikevičius; Jaroslav Vetrov

    2012-01-01

    This study was driven by the dissimilar performance characteristics displayed by asset classes over the business cycle. The authors aim to explore assets classes on the grounds of a scientific literature review and a statistical analysis. Business cycles are divided into four stages to explore broad movements in returns of asset classes and a possible existence of asymmetrical effects of determinants within stages. Six main asset classes were analysed: US stocks, EAFE stocks, Bonds, Gold, Rea...

  17. 7 CFR 201.69 - Classes of certified seed.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Classes of certified seed. 201.69 Section 201.69..., Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED ACT REGULATIONS Certified Seed § 201.69 Classes of certified seed. (a) Classes of certified seed are as...

  18. The Cultures of Social Class and Religious Educational Practice

    Science.gov (United States)

    Turpin, Katherine

    2009-01-01

    Although social class impacts the assumptions, values, and normative practices of Religious Education, the lack of public discourse on class diminishes awareness of and critical reflection on this impact. This article describes social class as a largely unarticulated and embodied performance of identity inflected through hierarchical practices of…

  19. Determinants of Student Performance in an Undergraduate Financial Accounting Class

    OpenAIRE

    Harrington, Donna Ramirez; Kulasekera, Kumuduni; Bates, Rick; Bredahl, Maury E.

    2006-01-01

    This study investigates the effects of class size, high school accounting, aptitude and attitude on learning , measured by the difference between post-test and pre-test scores, in an undergraduate financial accounting class, after controlling for students' major and semester level. Statistical analysis showed that scores of students in small classes improved by 48%, while scores of students in the large classes improved by 6% percent, implying a decline in learning by 88% by shifting to large...

  20. 39 CFR 775.5 - Classes of actions.

    Science.gov (United States)

    2010-07-01

    ... 40 CFR 1508.27. (b) Actions requiring an environmental assessment. Classes of actions that will... 39 Postal Service 1 2010-07-01 2010-07-01 false Classes of actions. 775.5 Section 775.5 Postal... PROCEDURES § 775.5 Classes of actions. (a) Actions which normally require an environment impact...

  1. Comparison of interradicular distances and cortical bone thickness in Thai patients with Class I and Class II skeletal patterns using cone-beam computed tomography

    Science.gov (United States)

    Khumsarn, Nattida; Patanaporn, Virush; Jotikasthira, Dhirawat

    2016-01-01

    Purpose This study evaluated and compared interradicular distances and cortical bone thickness in Thai patients with Class I and Class II skeletal patterns, using cone-beam computed tomography (CBCT). Materials and Methods Pretreatment CBCT images of 24 Thai orthodontic patients with Class I and Class II skeletal patterns were included in the study. Three measurements were chosen for investigation: the mesiodistal distance between the roots, the width of the buccolingual alveolar process, and buccal cortical bone thickness. All distances were recorded at five different levels from the cementoenamel junction (CEJ). Descriptive statistical analysis and t-tests were performed, with the significance level for all tests set at p<0.05. Results Patients with a Class II skeletal pattern showed significantly greater maxillary mesiodistal distances (between the first and second premolars) and widths of the buccolingual alveolar process (between the first and second molars) than Class I skeletal pattern patients at 10 mm above the CEJ. The maxillary buccal cortical bone thicknesses between the second premolar and first molar at 8 mm above the CEJ in Class II patients were likewise significantly greater than in Class I patients. Patients with a Class I skeletal pattern showed significantly wider mandibular buccolingual alveolar processes than did Class II patients (between the first and second molars) at 4, 6, and 8 mm below the CEJ. Conclusion In both the maxilla and mandible, the mesiodistal distances, the width of the buccolingual alveolar process, and buccal cortical bone thickness tended to increase from the CEJ to the apex in both Class I and Class II skeletal patterns. PMID:27358819

  2. Adolescent Students’ Intercultural Awareness When Using Culture-Based Materials in the English Class

    Directory of Open Access Journals (Sweden)

    Castañeda Usaquén Mireya Esther

    2012-04-01

    Full Text Available This article reports on a qualitative and interpretative case study conducted at a high school located in the southeast of Bogotá. The case is comprised of a group of fifty-one eighth graders who had had little contact with English. It aimed at exploring how these adolescents made sense of the culture-based materials implemented in the English lessons, and at describing their perceptions about foreign cultures. Video and audio recordings, surveys, field notes and students' artifacts were used to collect data. In this article, teachers can find some materials and reflections upon cultures as well as some ideas on how they can be adapted to their own needs and/or teaching contexts.

    En este artículo se reporta un estudio de caso de tipo cualitativo e interpretativo que se realizó en un colegio público del suroriente de Bogotá, con un grupo de cincuenta y un estudiantes del grado octavo, quienes tenían poco contacto con el idioma inglés. El objetivo fue explorar cómo estos adolescentes entendían los materiales con contenido cultural usados en las clases de inglés y describir sus percepciones de las culturas extranjeras presentadas en los materiales. Se recolectó información mediante grabaciones de video y audio, encuestas, diario de campo y material elaborado por los estudiantes. En este artículo, los profesores pueden encontrar materiales y reflexiones sobre culturas y adaptarlos a sus necesidades o contextos.

  3. Sensitivity Analysis of Gas Production from Class 2 and Class 3 Hydrate Deposits

    Energy Technology Data Exchange (ETDEWEB)

    Reagan, Matthew; Moridis, George; Zhang, Keni

    2008-05-01

    Gas hydrates are solid crystalline compounds in which gas molecules are lodged within the lattices of an ice-like crystalline solid. The vast quantities of hydrocarbon gases trapped in hydrate formations in the permafrost and in deep ocean sediments may constitute a new and promising energy source. Class 2 hydrate deposits are characterized by a Hydrate-Bearing Layer (HBL) that is underlain by a saturated zone of mobile water. Class 3 hydrate deposits are characterized by an isolated Hydrate-Bearing Layer (HBL) that is not in contact with any hydrate-free zone of mobile fluids. Both classes of deposits have been shown to be good candidates for exploitation in earlier studies of gas production via vertical well designs - in this study we extend the analysis to include systems with varying porosity, anisotropy, well spacing, and the presence of permeable boundaries. For Class 2 deposits, the results show that production rate and efficiency depend strongly on formation porosity, have a mild dependence on formation anisotropy, and that tighter well spacing produces gas at higher rates over shorter time periods. For Class 3 deposits, production rates and efficiency also depend significantly on formation porosity, are impacted negatively by anisotropy, and production rates may be larger, over longer times, for well configurations that use a greater well spacing. Finally, we performed preliminary calculations to assess a worst-case scenario for permeable system boundaries, and found that the efficiency of depressurization-based production strategies are compromised by migration of fluids from outside the system.

  4. Universality classes of foraging with resource renewal

    Science.gov (United States)

    Chupeau, M.; Bénichou, O.; Redner, S.

    2016-03-01

    We determine the impact of resource renewal on the lifetime of a forager that depletes its environment and starves if it wanders too long without eating. In the framework of a minimal starving random-walk model with resource renewal, there are three universal classes of behavior as a function of the renewal time. For sufficiently rapid renewal, foragers are immortal, while foragers have a finite lifetime otherwise. In the specific case of one dimension, there is a third regime, for sufficiently slow renewal, in which the lifetime of the forager is independent of the renewal time. We outline an enumeration method to determine the mean lifetime of the forager in the mortal regime.

  5. James Clerk Maxwell's class of 1856/57

    CERN Document Server

    Reid, John S

    2015-01-01

    James Clerk Maxwell is known for his outstanding contributions to fundamental physics. These include providing the equations that govern electric and magnetic fields, establishing the basis of modern colourimetry, finding important relationships in thermodynamics, molecular science, mechanics, optics and astronomy. In his first Professorial chair in 1856 at the Marischal College and University of Aberdeen he undertook a substantial amount of teaching that laid the foundation for his later pedagogic output. This paper examines whom he taught, where his first students came from and what they did in later life, drawing material from a privately published memoir. Thumbnail portraits are included for 70% of his class. The analysis complements the usual emphasis on educational method and content. The data provide an interesting sociological survey of what Scottish University education was achieving in the middle of the 19th century and is presented as raw material for a wider enquiry.

  6. Calculating the Carbon Footprint from Different Classes of Air Travel

    OpenAIRE

    Bofinger, Heinrich; Strand, Jon

    2013-01-01

    This paper develops a new methodology for calculating the "carbon footprint" of air travel whereby emissions from travel in premium (business and first) classes depend heavily on the average class-specific occupied floor space. Unlike methods currently used for the purpose, the approach properly accounts for the fact that the relative number of passenger seats in economy and premium classe...

  7. Polynomial Operators on Classes of Regular Languages

    Science.gov (United States)

    Klíma, Ondřej; Polák, Libor

    We assign to each positive variety mathcal V and each natural number k the class of all (positive) Boolean combinations of the restricted polynomials, i.e. the languages of the form L_0a_1 L_1a_2dots a_ell L_ell, text{ where } ell≤ k, a 1,...,a ℓ are letters and L 0,...,L ℓ are languages from the variety mathcal V. For this polynomial operator we give a certain algebraic counterpart which works with identities satisfied by syntactic (ordered) monoids of languages considered. We also characterize the property that a variety of languages is generated by a finite number of languages. We apply our constructions to particular examples of varieties of languages which are crucial for a certain famous open problem concerning concatenation hierarchies.

  8. A General Class of Metamaterial Transformation Slabs

    CERN Document Server

    Gallina, Ilaria; Galdi, Vincenzo; Alu', Andrea; Engheta, Nader

    2009-01-01

    In this paper, we apply transformation-based optics to the derivation of a general class of transparent metamaterial slabs. By means of analytical and numerical full-wave studies, we explore their image displacement/formation capabilities, and establish intriguing connections with configurations already known in the literature. Starting from these revisitations, we develop a number of nontrivial extensions, and illustrate their possible applications to the design of perfect radomes, anti-cloaking devices, and super-resolving lenses based on double-positive (possibly nonmagnetic) media. These designs show that such anomalous features may be achieved without necessarily relying on negative-index or strongly resonant metamaterials, suggesting more practical venues for the realization of these devices.

  9. Anticancer properties of distinct antimalarial drug classes.

    Directory of Open Access Journals (Sweden)

    Rob Hooft van Huijsduijnen

    Full Text Available We have tested five distinct classes of established and experimental antimalarial drugs for their anticancer potential, using a panel of 91 human cancer lines. Three classes of drugs: artemisinins, synthetic peroxides and DHFR (dihydrofolate reductase inhibitors effected potent inhibition of proliferation with IC50s in the nM- low µM range, whereas a DHODH (dihydroorotate dehydrogenase and a putative kinase inhibitor displayed no activity. Furthermore, significant synergies were identified with erlotinib, imatinib, cisplatin, dasatinib and vincristine. Cluster analysis of the antimalarials based on their differential inhibition of the various cancer lines clearly segregated the synthetic peroxides OZ277 and OZ439 from the artemisinin cluster that included artesunate, dihydroartemisinin and artemisone, and from the DHFR inhibitors pyrimethamine and P218 (a parasite DHFR inhibitor, emphasizing their shared mode of action. In order to further understand the basis of the selectivity of these compounds against different cancers, microarray-based gene expression data for 85 of the used cell lines were generated. For each compound, distinct sets of genes were identified whose expression significantly correlated with compound sensitivity. Several of the antimalarials tested in this study have well-established and excellent safety profiles with a plasma exposure, when conservatively used in malaria, that is well above the IC50s that we identified in this study. Given their unique mode of action and potential for unique synergies with established anticancer drugs, our results provide a strong basis to further explore the potential application of these compounds in cancer in pre-clinical or and clinical settings.

  10. Latent Trajectory Classes of Depressive and Anxiety Disorders from Adolescence to Adulthood: Descriptions of Classes and Associations with Risk Factors

    OpenAIRE

    Olino, Thomas M.; Klein, Daniel N.; Lewinsohn, Peter M.; Rohde, Paul; John R. Seeley

    2009-01-01

    The study used person-oriented analyses to identify subgroups of individuals who exhibit different patterns of depressive and anxiety disorders over the course of adolescence and young adulthood. Using latent class growth analysis, six trajectory classes were identified. Two classes were mainly characterized by depressive disorders; one was mainly characterized by anxiety disorders; two were characterized by temporally different patterns of comorbidity; and one class was characterized by the ...

  11. Tukey classes of ultrafilters on omega

    CERN Document Server

    Milovich, David

    2008-01-01

    Motivated by a question of Isbell, we show that Jensen's Diamond Principle implies there is a non-P-point ultrafilter U on omega such that U, whether ordered by reverse inclusion or reverse inclusion mod finite, is not Tukey equivalent to the finite sets of reals ordered by inclusion. We also show that, for every regular infinite kappa not greater than 2^{aleph_0}, if MA_{sigma-centered} holds, then some ultrafilter U on omega, ordered by reverse inclusion mod finite, is Tukey equivalent to the sets of reals of size less than kappa, ordered by inclusion. We also prove two negative ZFC results about the possible Tukey classes of ultrafilters on omega.

  12. Arithmetic crystal classes of magnetic symmetries

    International Nuclear Information System (INIS)

    The symmetries and properties of a broad class of magnetic crystals are described by magnetic space groups which contain both (unitary) spatial symmetry operations and their combinations with the (anti-unitary operation of) time inversion, 0. The spatial symmetry operations form a halving, non-magnetic, space group H of the magnetic group M such that M=H+aH. As an abstract group the magnetic group M is isomorphic to a non-magnetic group G. The anti-unitary operator a is simply the time inversion 0 when M is a grey group but a product of time inversion with some spatial operation belonging to the coset G-H when M is a black-and-white group. (Author)

  13. Is the class of all fuzzy rings a fuzzy HSP-class?

    Directory of Open Access Journals (Sweden)

    Nistala V. E. S. Murthy

    2003-09-01

    Full Text Available The aim of this paper is to generalize, the notion of fuzzy subring of a crisp ring to that of a fuzzy ring and the notion of crisp homomorphism between crisp rings with fuzzy direct image and fuzzy inverse image to that of a fuzzy homomorphism between fuzzy rings with truth values in different complete lattices, with fuzzy direct and inverse images, in such a way that the class of all fuzzy rings is in fact a fuzzy HSP-Class. In the process several elementary but important properties that naturally extended, are recorded including Correspondence and Isomorphism Theorems.

  14. Classes of hydrodynamic and magnetohydrodynamic turbulent decay

    CERN Document Server

    Brandenburg, Axel

    2016-01-01

    We perform numerical simulations of decaying hydrodynamic and magnetohydrodynamic turbulence. We classify our time-dependent solutions by their evolutionary tracks in parametric plots between instantaneous scaling exponents. We find distinct classes of solutions evolving along specific trajectories toward points on a line of self-similar solutions. These trajectories are determined by the underlying physics governing individual cases, and not by the initial conditions, as is widely assumed. In the helical case, even for a scale-invariant initial spectrum (inversely proportional to wavenumber k), the solution evolves along the same trajectory as for a Batchelor spectrum (proportional to k^4). All of our self-similar solutions have an intrinsic subinertial range close to k^4$.

  15. Identifying Clusters of Concepts in a Low Cohesive Class for Extract Class Refactoring Using Metrics Supplemented Agglomerative Clustering Technique

    CERN Document Server

    Rao, A Ananda

    2012-01-01

    Object oriented software with low cohesive classes can increase maintenance cost. Low cohesive classes are likely to be introduced into the software during initial design due to deviation from design principles and during evolution due to software deterioration. Low cohesive class performs operations that should be done by two or more classes. The low cohesive classes need to be identified and refactored using extract class refactoring to improve the cohesion. In this regard, two aspects are involved; the first one is to identify the low cohesive classes and the second one is to identify the clusters of concepts in the low cohesive classes for extract class refactoring. In this paper, we propose metrics supplemented agglomerative clustering technique for covering the above two aspects. The proposed metrics are validated using Weyuker's properties. The approach is applied successfully on two examples and on a case study.

  16. Spectral energy distribution analysis of class I and class II FU Orionis stars

    Energy Technology Data Exchange (ETDEWEB)

    Gramajo, Luciana V.; Gómez, Mercedes [Observatorio Astronómico, Universidad Nacional de Córdoba, Argentina, Laprida 854, 5000 Córdoba (Argentina); Rodón, Javier A., E-mail: luciana@oac.uncor.edu, E-mail: mercedes@oac.uncor.edu, E-mail: jrodon@eso.org [European Southern Observatory, Alonso de Córdova 3107, Vitacura, Casilla 19001, Santiago 19 (Chile)

    2014-06-01

    FU Orionis stars (FUors) are eruptive pre-main sequence objects thought to represent quasi-periodic or recurring stages of enhanced accretion during the low-mass star-forming process. We characterize the sample of known and candidate FUors in a homogeneous and consistent way, deriving stellar and circumstellar parameters for each object. We emphasize the analysis in those parameters that are supposed to vary during the FUor stage. We modeled the spectral energy distributions of 24 of the 26 currently known FUors, using the radiative transfer code of Whitney et al. We compare our models with those obtained by Robitaille et al. for Taurus class II and I sources in quiescence periods by calculating the cumulative distribution of the different parameters. FUors have more massive disks: we find that ∼80% of the disks in FUors are more massive than any Taurus class II and I sources in the sample. Median values for the disk mass accretion rates are ∼10{sup –7} M {sub ☉} yr{sup –1} versus ∼10{sup –5} M {sub ☉} yr{sup –1} for standard young stellar objects (YSOs) and FUors, respectively. While the distributions of envelope mass accretion rates for class I FUors and standard class I objects are similar, FUors, on average, have higher envelope mass accretion rates than standard class II and class I sources. Most FUors (∼70%) have envelope mass accretion rates above 10{sup –7} M {sub ☉} yr{sup –1}. In contrast, 60% of the classical YSO sample has an accretion rate below this value. Our results support the current scenario in which changes experimented by the circumstellar disk explain the observed properties of these stars. However, the increase in the disk mass accretion rate is smaller than theoretically predicted, although in good agreement with previous determinations.

  17. The effects of mixed-age classes in Sweden

    OpenAIRE

    Johansson, Elly-Ann; Lindahl, Erica

    2008-01-01

    Mixed-aged classes (MA-classes) are a common phenomenon around the world. In Sweden, these types of classes increased rapidly during the 1980:s and 1990:s. But the scientific evidence of the benefits of MA-classes is not convincing. In this paper, we estimate the effect of attending an MA-class during grades 4–6 on students’ cognitive skills. Using a unique survey with information on students, parents and teachers, we are able to control for many factors that could otherwise bias the results....

  18. The concept of class: the sociology school books and the proposal of E. P. Thompson

    Directory of Open Access Journals (Sweden)

    Kênia Mara Gaedtke

    2015-12-01

    Full Text Available The paper proposes an analysis of new textbooks of sociology made available by the Ministry of Education from the National Textbook Program ( PNLD in 2014 , with specific focus on how the notion of class is treated in each of the materials in question. Starting from the notion of class advocated by British historian E.P. Thompson, we observe advances in theoretical and conceptual quality of the books provided by the program, but still a distance from the thompsonian proposal, which sees class does not like a tight concept, but as a relationship that takes place as active and historical process.

  19. The Association of HLA-Class I and Class II with Hodgkin’s Lymphoma in Iranian Patients

    OpenAIRE

    Arezou Sayad; Mohammad Taghi Akbari; Mahshid Mehdizadeh; Abolfazl Movafagh; Abbas Hajifathali

    2014-01-01

    The Hodgkin's lymphoma disease (HD) is a common malignant neoplasm with germinal centre B-cell origin. It has been suggested that the HLA class I and class II regions have susceptibility effects on HD. In different ethnic groups, different HLA class I and class II alleles affect HD. As a result, there is no consensus which of the different HLA alleles confers susceptibility to HD. In this study, we aimed to ascertain the role of HLA class I and class II alleles in association with Hodgkin's l...

  20. Class Attendance in College: A Meta-Analytic Review of the Relationship of Class Attendance with Grades and Student Characteristics

    Science.gov (United States)

    Crede, Marcus; Roch, Sylvia G.; Kieszczynka, Urszula M.

    2010-01-01

    A meta-analysis of the relationship between class attendance in college and college grades reveals that attendance has strong relationships with both class grades (k = 69, N = 21,195, p = 0.44) and GPA (k = 33, N = 9,243, p = 0.41). These relationships make class attendance a better predictor of college grades than any other known predictor of…

  1. Effect of Problem Based Learning Scenario on Knowledge of Third Class Students About Childhood Poisoning

    OpenAIRE

    Nazan Karaoğlu; Sevgi Pekcan; Burak Cem Soner; Muzaffer Şeker; Rahmi Örs

    2011-01-01

    Introduction: It is stated that students cannot carry their knowledge on basic medical sciences that they gained with classical education to clinical classes and clinical practice and problem based learning (PBL) can compensate this drawback. It was aimed to evaluate the effect of PBL scenario written on this topic on level of knowledge about childhood poisoning of third class students who completed the most of theoretical pharmacology education.Materials and Method: A questionnaire form prep...

  2. The Microfloral Analysis of Secondary Caries Biofilm around Class I and Class II Composite and Amalgam Fillings

    Directory of Open Access Journals (Sweden)

    Mo Si-su

    2010-08-01

    Full Text Available Abstract Background Secondary caries is responsible for 60 percent of all replacement restorations in the typical dental practice. The diversity of the bacterial sources and the different types of filling materials could play a role in secondary caries. The aim of this study was to determine and compare the microbial spectrum of secondary caries biofilms around amalgam and composite resin restorations. Methods Clinical samples were collected from freshly extracted teeth diagnosed with clinical secondary caries. Samples were categorized into four groups according to the types of restoration materials and the classification of the cavity. Biofilms were harvested from the tooth-restoration interface using a dental explorer and after dilution were incubated on special agars. The bacteria were identified using the biochemical appraisal system. Statistical calculations were carried out using SPSS11.5 software to analyze the prevalence of the bacteria involved in secondary caries. Results Samples from a total of four groups were collected: two groups were collected from amalgam restorations, each had 21 samples from both Class I and Class II caries; and the other two groups were from composite resin restorations, each had 13 samples from both class I and class II caries. Our results showed: (1 Anaerobic species were dominant in both restoration materials. (2 In terms of the types of individual bacteria, no significant differences were found among the four groups according to the geometric mean of the detected bacteria (P > 0.05. However, there were significant differences among the detected bacteria within each group (P 0.05, but showed significant differences among the detected bacteria in each group (P 0.05, however, the detection rate of each bacterium within each group was statistically different among the detected bacteria (P Conclusions The proportion of obligatory anaerobic species was much greater than the facultative anaerobic species in the

  3. On a Class of Semicommutative Modules

    Indian Academy of Sciences (India)

    Nazim Agayev; Tahire Özen; Abdullah Harmanci

    2009-04-01

    Let be a ring with identity, a right -module and $S=\\mathrm{End}_R(M)$. In this note, we introduce -semicommutative, -Baer, $S-q.$-Baer and $S-p.q.$-Baer modules. We study the relations between these classes of modules. Also we prove if is an -semicommutative module, then is an $S-p.q.$-Baer module if and only if $M[x]$ is an $S[x]-p.q.$-Baer module, is an -Baer module if and only if $M[x]$ is an $S[x]$-Baer module, is an $S-q.$-Baer module if and only if $M[x]$ is an $S[x]-q.$-Baer module.

  4. Clinical implication of HLA class I expression in breast cancer

    International Nuclear Information System (INIS)

    Human leukocyte antigen (HLA)-class I molecules on tumor cells have been regarded as crucial sites where cytotoxic T lymphocytes (CTL) can recognize tumor-specific antigens and are strongly associated with anti-tumor activity. However, the clinical impact of HLA class I expression in breast cancer has not been clarified. A total of 212 breast cancer patients who received curative surgery from 1993 to 2003 were enrolled in the current study. HLA class I expression was examined immunohistochemically using an anti-HLA class I monoclonal antibody. The correlation between HLA class I positivity and clinical factors was analyzed. The downregulation of HLA class I expression in breast cancer was observed in 69 patients (32.5%). HLA class I downregulation was significantly associated with nodal involvement (p < 0.05), TNM stage (p < 0.05), lymphatic invasion (p < 0.01), and venous invasion (p < 0.05). Patients with preserved HLA class I had significantly better disease-free interval (DFI) than those with loss of HLA class I (p < 0.05). However, in multivariable analysis, HLA class I was not selected as one of the independent prognostic factors of disease-free interval. The examination of HLA class I expression is useful for the prediction of tumor progression and recurrent risk of breast cancer via the antitumor immune system

  5. Social-Class Differences in Consumer Choices: Working-Class Individuals Are More Sensitive to Choices of Others Than Middle-Class Individuals.

    Science.gov (United States)

    Na, Jinkyung; McDonough, Ian M; Chan, Micaela Y; Park, Denise C

    2016-04-01

    The present research shows that, when making choices, working-class Americans are more affected by others' opinions than middle-class Americans due to differences in independent versus interdependent self-construal. Experiment 1 revealed that when working-class Americans made decisions to buy products, they were more influenced by the choices of others than middle-class Americans. In contrast, middle-class Americans were more likely to misremember others' choices to be consistent with their own choices. In other words, working-class Americans adjusted their choices to the preference of others, whereas middle-class Americans distorted others' preferences to fit their choices. Supporting our prediction that this social-class effect is closely linked to the independent versus interdependent self-construal, we showed that the differences in self-construal across cultures qualified the social-class effects on choices (Experiment 2). Moreover, when we experimentally manipulated self-construal in Experiment 3, we found that it mediated the corresponding changes in choices regardless of social class. PMID:26984010

  6. Class Size: Can School Districts Capitalize on the Benefits of Smaller Classes?

    Science.gov (United States)

    Hertling, Elizabeth; Leonard, Courtney; Lumsden, Linda; Smith, Stuart C.

    2000-01-01

    This report is intended to help policymakers understand the benefits of class-size reduction (CSR). It assesses the costs of CSR, considers some research-based alternatives, and explores strategies that will help educators realize the benefits of CSR when it is implemented. It examines how CSR enhances student achievement, such as when the…

  7. Dynamical systems with first- and second-class constraints. I. Separation of constraints into first and second classes

    International Nuclear Information System (INIS)

    In the Dirac approach to the generalized Hamiltonian formalism, dynamical systems with first- and second-class constraints are investigated. The classification and separation of constraints into the first- and second-class ones are presented with the help of passing to an equivalent canonical set of constraints. The general structure of second-class constraints is clarified. copyright 1997 The American Physical Society

  8. The Method of Manufacturing Nonmetallic Test-Blocks on Different Sensitivity Classes

    Science.gov (United States)

    Kalinichenko, N. P.; Kalinichenko, A. N.; Lobanova, I. S.; Zaitseva, A. A.; Loboda, E. L.

    2016-01-01

    Nowadays in our modern world there is a vital question of quality control of details made from nonmetallic materials due to their wide spreading. Nondestructive penetrant testing is effective, and in some cases it is the only possible method of accidents prevention at high- risk sites. A brief review of check sample necessary for quality evaluation of penetrant materials is considered. There was offered a way of making agents for quality of penetrant materials testing according to different liquid penetrant testing sensibility classes.

  9. Can Technology Improve Large Class Learning? The Case of an Upper-Division Business Core Class

    Science.gov (United States)

    Stanley, Denise

    2013-01-01

    Larger classes are often associated with lower student achievement. The author tested the hypothesis that the introduction of personal response systems significantly improves scores in a 250-seat classroom, through the channels of improved attendance and engagement. She focused on how continuous participation with the technology could change…

  10. Chromium-manganese steels of transition class

    International Nuclear Information System (INIS)

    Possibilities of nickel replacing by manganese and preparing the same level of mechanical properties as in chromium-nickel steels due to γ-α transformations taking place during property tests, are studied. Chromium-manganese steels with the composition of 0.05-0.1%C, 13-14%Cr, 5.0-6.5%Mn, 0.2-0.5%Si, 0.03-0.13%N, 0.05-0.01%Al and additionally alloyed 0.3-2.0%Cu, 0.05-0.6%V, 0.3-1.0%Mo, 0.02-0.05%Ca in various combinations have been melted. It is shown, that using alloying and heat treatment one can control the phase composition, austenite resistance to martensite transformation during loading and mechanical properties of chromium-manganese steels of the transition class. The use of the phase transformation in the process of testing determines the level of mechanical properties. The optimum development of the transformation accompanied by a sufficient development of processes of hardening and microstresses relaxation permits to obtain a high level of mechanical properties: σsub(B)=1500 MPa, σsub(0.2)-1130MPa, delta=15%, psi=37%, asub(H)=1000 kJ/msup(2) which exceeds the level for chromium-nickel steels. Steels have a lower cost and do not require any complecated heat treatment regime

  11. Classes of source pairs in interference and diffraction

    CERN Document Server

    Castaneda, R

    2003-01-01

    A description of interference and diffraction based on the concept of class of source pairs is presented. It is the set of pairs of sources whose contributions to the interference or diffraction patterns exhibit the same phase difference. Each class of source pairs provides a specific cosine-like modulation on the intensity distribution of pattern, in such a way that the set provides an expansion of the intensity distribution of the pattern in an orthogonal basis. From this point of view, the classes of source pairs are the effective elementary sources for those intensity distributions. The characteristics of the classes of source pairs can be accurately determined by Fourier transforming the intensity distribution of the patterns. The central value of this Fourier spectrum is related to the number of individual sources. The remaining values will provide two crucial descriptors of the classes: their positions on the Fourier transform domain will be corresponding to the separation vector of the class of pairs ...

  12. The bioenergetics of World Class Cycling.

    Science.gov (United States)

    Jeukendrup, A E; Craig, N P; Hawley, J A

    2000-12-01

    Professional cycle racing is one of the most demanding of all sports combining extremes of exercise duration, intensity and frequency. Riders are required to perform on a variety of surfaces (track, road, cross-country, mountain), terrains (level, uphill and downhill) and race situations (criterions, sprints, time trials, mass-start road races) in events ranging in duration from 10 s to 3 wk stage races covering 200 m to 4,000 km. Furthermore, professional road cyclists typically have approximately 100 race d/yr. Because of the diversity of cycle races, there are vastly different physiological demands associated with the various events. Until recently there was little information on the demands of professional cycling during training or competition. However, with the advent of reliable, valid bicycle crank dynanometers, it is now possible to quantify real-time power output, cadence and speed during a variety of track and road cycling races. This article provides novel data on the physiological demands of professional and world-class amateur cyclists and characterises some of the physiological attributes necessary for success in cycling at the élite level. PMID:11235007

  13. Simultaneous observation of water and class I methanol masers toward class II methanol maser sources

    CERN Document Server

    Kang, Hyunwoo; Byun, Do-Young; Lee, Seokho; Park, Yong-Sun

    2015-01-01

    We present a simultaneous single-dish survey of 22 GHz water maser and 44 GHz and 95 GHz class I methanol masers toward 77 6.7 GHz class II methanol maser sources, which were selected from the Arecibo methanol maser Galactic plane survey (AMGPS) catalog.Water maser emission is detected in 39 (51%) sources, of which 15 are new detections. Methanol maser emission at 44 GHz and 95 GHz is found in 25 (32%) and 19 (25%) sources, of which 21 and 13 sources are newly detected, respectively. We find 4 high-velocity (> 30 km/s) water maser sources, including 3 dominant blue- or redshifted outflows.The 95 GHz masers always appear with the 44 GHz maser emission. They are strongly correlated with 44 GHz masers in velocity, flux density, and luminosity, while they are not correlated with either water or 6.7 GHz class II methanol masers. The average peak flux density ratio of 95 GHz to 44 GHz masers is close to unity, which is two times higher than previous estimates. The flux densities of class I methanol masers are more ...

  14. The Material Roots of Western Racism

    OpenAIRE

    Freeman, Alan

    1998-01-01

    This article assesses the US discussion on the material roots of racism in which writers such as Malcolm X have been heavily criticised by ‘marxists’ for substituting race for class in the analysis of society. The article argues that such criticism departs from the classical Marxist tradition in a manner characteristic of the dominant countries of the world in subordinating issues of political rights to the economic class struggle. This in turn arises from a failure to recognise the rela...

  15. 78 FR 5754 - Proposed Amendment of Class D and Class E Airspace; Reading, PA

    Science.gov (United States)

    2013-01-28

    ... Procedures (44 FR 11034; February 26, 1979); and (3) does not warrant preparation of a Regulatory Evaluation... continues to read as follows: Authority: 49 U.S.C. 106(g); 40103, 40113, 40120; E.O. 10854, 24 FR 9565, 3... Class E Airspace; Reading, PA AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice...

  16. Study of a new class of nonlinear inextensible elastic bodies

    Science.gov (United States)

    Bustamante, R.; Rajagopal, K. R.

    2015-12-01

    In this paper, we study the consequences of the constraint of inextensibility with regard to a class of constitutive relations, where the strain is given as a function of the stress. Such constitutive equations belong to a wider class of implicit constitutive relations, which have been proposed recently in the literature.

  17. Zintl phase compounds AM2Sb2 (A=Ca, Sr, Ba, Eu, Yb;M=Zn, Cd) and their substitution variants:a class of potential thermoelectric materials

    Institute of Scientific and Technical Information of China (English)

    郭凯; 操齐高; 赵景泰

    2013-01-01

    Zintl phase compounds AM2Sb2 (A=Ca, Sr, Ba, Eu, Yb;M=Zn, Cd) is a new class of promising thermoelectrics owing to their intrinsic features in electronic and crystal structure, such as a small or even disappeared band-gap, large density-of-states at the Fermi level, covalently bonded network of M-Sb, as well as the layered stacking by cations A2+and anionic slabs (M2Sb2)2-. In addi-tion, the rich solid-state chemistry of Zintl phase allows structural modification and chemical substitution to adjust the fundamental transport parameters (carrier concentration, mobility, effective mass, electronic and lattice thermal conductivity) for improving the thermoelectric performance. In the present review, the recent advances in synthesis and thermoelectric characterization of title com-pounds AM2Sb2 were presented, and the effects of alloying or substitution for sites A, M and Sb on the electrical and thermal trans-port were emphasized. The structural disorder yielded by the incorporation of multiple ions significantly increased the thermoelectric figure of merit mainly resulted from the reduction of thermal conductivity without disrupting the carrier transport region in substance. Therefore, alloying or substitution has been a feasible and common route utilized to enhance thermoelectric properties in these Zintl phase compounds, especially for YbZn0.4Cd1.6Sb2 (ZT700 K=1.26), EuZn1.8Cd0.2Sb2 (ZT650 K=1.06), and YbCd1.85Mn0.15Sb2 (ZT650 K=1.14).

  18. 既有建筑拆除物碎砖类骨料再生混凝土的可行性研究%Feasibility Study of the Exiting Building Demolition Material the Brickbat Class Aggregate of Recycled Concrete

    Institute of Scientific and Technical Information of China (English)

    童滋捷; 宗兰; 张士萍

    2012-01-01

    By using the exiting buildings to remove material broken bricks as aggregate , this article describes the background and purpose of preparation of recycled concrete. And, it has done a feasibility study about preparation of recycled concrete contents , steps, technologies routes and so on .%文章介绍了利用既有建筑拆除物碎砖作为骨料,制备再生混凝土的研究背景及目的,并对既有建筑拆除物中的碎砖作为骨料.制备再生混凝土的研究内容、步骤、技术路线等方面做了可行性研究。

  19. Comprehensive analysis of cooperative gene mutations between class I and class II in de novo acute myeloid leukemia.

    Science.gov (United States)

    Ishikawa, Yuichi; Kiyoi, Hitoshi; Tsujimura, Akane; Miyawaki, Shuichi; Miyazaki, Yasushi; Kuriyama, Kazutaka; Tomonaga, Masao; Naoe, Tomoki

    2009-08-01

    Acute myeloid leukemia (AML) has been thought to be the consequence of two broad complementation classes of mutations: class I and class II. However, overlap-mutations between them or within the same class and the position of TP53 mutation are not fully analyzed. We comprehensively analyzed the FLT3, cKIT, N-RAS, C/EBPA, AML1, MLL, NPM1, and TP53 mutations in 144 newly diagnosed de novo AML. We found 103 of 165 identified mutations were overlapped with other mutations, and most overlap-mutations consisted of class I and class II mutations. Although overlap-mutations within the same class were found in seven patients, five of them additionally had the other class mutation. These results suggest that most overlap-mutations within the same class might be the consequence of acquiring an additional mutation after the completion both of class I and class II mutations. However, mutated genes overlapped with the same class were limited in N-RAS, TP53, MLL-PTD, and NPM1, suggesting the possibility that these irregular overlap-mutations might cooperatively participate in the development of AML. Notably, TP53 mutation was overlapped with both class I and class II mutations, and associated with morphologic multilineage dysplasia and complex karyotype. The genotype consisting of complex karyotype and TP53 mutation was an unfavorable prognostic factor in entire AML patients, indicating this genotype generates a disease entity in de novo AML. These results collectively suggest that TP53 mutation might be a functionally distinguishable class of mutation. PMID:19309322

  20. Classes of feedforward neural networks and their circuit complexity

    OpenAIRE

    Shawe-Taylor, John S.; Anthony, Martin H.G.; Kern, Walter

    1992-01-01

    This paper aims to place neural networks in the context of boolean circuit complexity. We define appropriate classes of feedforward neural networks with specified fan-in, accuracy of computation and depth and using techniques of communication complexity proceed to show that the classes fit into a well-studied hierarchy of boolean circuits. Results cover both classes of sigmoid activation function networks and linear threshold networks. This provides a much needed theoretical basis for the stu...

  1. Genetic Enhancement and the Biopolitical Horizon of Class Conflict

    Directory of Open Access Journals (Sweden)

    Wade Roberts

    2010-01-01

    Full Text Available In this paper I argue that the widespread use of liberal eugenics  would establish a biopolitical horizon for class conflict.  In the course of my discussion, I examine Foucault’s discussion of the origins of class racism in Society Must Be Defended.  I then turn to an examination of how a widespread use of genetic engineering could aggravate class divisions and produce new forms of class racism.  I conclude the essay with an overview of the political options which are available to opponents of liberal eugenics.

  2. The sinking of the Soviet Mike class nuclear powered submarine

    International Nuclear Information System (INIS)

    The purpose of this preliminary study is to assess the quantities of the longer-lived or persistent radioactive materials, or source terms, that have been lost at sea with the sinking of the Soviet MIKE class submarine off Bear Island on 7 April 1989. The report arrives at an assessment of the amount of radioactivity and compares this to the quantities of radioactive materials dumped by the UK from 1953 to 1982 at which time sea dumping of radioactive wastes was suspended by international resolve. This comparison can be used to assess the relative significance of the sinking of this submarine. The study does not extrapolate the estimated radioactive source terms to an environmental or radiological significance of the sinking, although it is concluded that unless the submarine is recovered intact from the ocean floor, the by far greater part of the radioactive materials on board will disperse to the marine environment at some future time, if they are not doing so already. (author)

  3. Genomic Characterization of Methanomicrobiales Reveals Three Classes of Methanogens

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, Iain; Ulrich, Luke E.; Lupa, Boguslaw; Susanti, Dwi; Porat, Iris; Hooper, Sean D.; Lykidis, Athanasios; Sieprawska-Lupa, Magdalena; Dharmarajan, Lakshmi; Goltsman, Eugene; Lapidus, Alla; Saunders, Elizabeth; Han, Cliff; Land, Miriam; Lucas, Susan; Mukhopadhyay, Biswarup; Whitman, William B.; Woese, Carl; Bristow, James; Kyrpides, Nikos

    2009-05-01

    Methanomicrobiales is the least studied order of methanogens. While these organisms appear to be more closely related to the Methanosarcinales in ribosomal-based phylogenetic analyses, they are metabolically more similar to Class I methanogens. In order to improve our understanding of this lineage, we have completely sequenced the genomes of two members of this order, Methanocorpusculum labreanum Z and Methanoculleus marisnigri JR1, and compared them with the genome of a third, Methanospirillum hungatei JF-1. Similar to Class I methanogens, Methanomicrobiales use a partial reductive citric acid cycle for 2-oxoglutarate biosynthesis, and they have the Eha energy-converting hydrogenase. In common with Methanosarcinales, Methanomicrobiales possess the Ech hydrogenase and at least some of them may couple formylmethanofuran formation and heterodisulfide reduction to transmembrane ion gradients. Uniquely, M. labreanum and M. hungatei contain hydrogenases similar to the Pyrococcus furiosus Mbh hydrogenase, and all three Methanomicrobiales have anti-sigma factor and anti-anti-sigma factor regulatory proteins not found in other methanogens. Phylogenetic analysis based on seven core proteins of methanogenesis and cofactor biosynthesis places the Methanomicrobiales equidistant from Class I methanogens and Methanosarcinales. Our results indicate that Methanomicrobiales, rather than being similar to Class I methanogens or Methanomicrobiales, share some features of both and have some unique properties. We find that there are three distinct classes of methanogens: the Class I methanogens, the Methanomicrobiales (Class II), and the Methanosarcinales (Class III).

  4. N=1 theories of class S_k

    OpenAIRE

    Gaiotto, Davide; Razamat, Shlomo S.

    2015-01-01

    We construct classes of ${\\cal N}=1$ superconformal theories elements of which are labeled by punctured Riemann surfaces. Degenerations of the surfaces correspond, in some cases, to weak coupling limits. Different classes are labeled by two integers (N,k). The k=1 case coincides with A_{N-1} ${\\cal N}=2$ theories of class S and simple examples of theories with k>1 are Z_k orbifolds of some of the A_{N-1} class S theories. For the space of ${\\cal N}=1$ theories to be complete in an appropriate...

  5. Thor: Modeling of a Megabar Class Pulsed Power Accelerator

    Science.gov (United States)

    Haill, T. A.; Reisman, D. B.; Stoltzfus, B. S.; Austin, K. N.; Stygar, W. A.; Brown, J. L.; Davis, J.-P.; Waisman, E. M.

    2015-06-01

    Thor is a compact, economical machine to drive megabar-class shockless compression material physics experiments and multi-mega-ampere HEDP experiments for the physics community. It is capable of driving peak currents up to 7 MA with rise times of 200-500 ns, resulting in material pressures between 1 to 5 Mbar depending upon the load design, and incorporates a pulse tailoring capability required to maintain shockless loading of many materials. Thor is modular in nature with 200 capacitive bricks triggered in groups by independent, de-coupled switches. The current pulse at the load is a simple linear combination of the 200 time-shifted basis pulses. This enables a variety of experiments including shockless compression experiments using smooth ramped pulses, shock-ramp compression experiments using tailored pulses, and strength measurement experiments using flat top pulses. This paper overviews the Thor design and describes an equivalent circuit model of the machine that drives MHD simulations of the load region. 3D ALEGRA MHD simulations explore topics such as the uniformity of the magnetic field along the stripline load and the design modifications to improve uniformity. Optimized current drives and simulations of the aforementioned applications are also presented. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Company, for the U.S. DOE's NNSA under Contract DE-AC04-94AL85000.

  6. Economic struggle and the class culture of workers

    OpenAIRE

    Branko Bembič

    2013-01-01

    Economic struggles are usually linked to the spontaneous working class ideology of fighting for a mere improvement in wages and working conditions. However, they often transcend their meagre economic results as they are indispensable in the construction of the working class culture of solidarity. Far from being spontaneous, the process of transforming the trade union orientation from class unionism to business unionism in the USA and to social partnership in Europe had to be imposed through s...

  7. THE PLACE OF LITERATURE CLASSES IN FRENCH LANGUAGE TEACHING PROGRAMS

    OpenAIRE

    Rıfat GÜNDAY

    2009-01-01

    The curriculum of teacher training programs has changed several times since 1982 when the management of the educational faculties has been left to YÖK. The curriculum has also covered core classes of literature in foreign language programs. However, core classes in literature have not remained static; they have rather changed in content, number, title and approach in teaching and analysis. In this study the place of literature classes in French Language Department Programs, the subsequent cha...

  8. Class characteristics of serrated knife stabs to cartilage.

    Science.gov (United States)

    Pounder, Derrick J; Cormack, Lesley; Broadbent, Elizabeth; Millar, John

    2011-06-01

    A total of 136 stab wounds were made in cartilage with 8 serrated knives and 72 stabs with 4 nonserrated knives. The walls of the stab track were documented by photography, cast with dental impression material, and the casts photographed. Staining the translucent cartilage surface with blue or green food dye improved photography. Serrated blades produced striations on cartilage in all stabbings. Patterns of blade serration beyond the broad categories of coarse and fine were recognizable. The overall pattern of striations was "irregularly regular." The distance between the blade-spine wound end and the first serration striation is a class characteristic of the knife which produced the defect, as are distances to the subsequent serration striations, which become ever close together and eventually merge near the blade-edge wound end. Serrated knives may be ground (scalloped) on either the left side or the right side of the blade and this class characteristic is identifiable from the walls of the wound track, on which the scalloped blade surface produces broad ridges and narrow striation valleys, with a reverse image on the opposing wound wall. A drop point serrated blade consistently produced an additional oblique mark angled from the blade-spine wound end, accurately reflecting the shape of the blade tip, and representing a chatter mark. PMID:20407362

  9. Representations of deaf students about inclusion in physical education classes

    Directory of Open Access Journals (Sweden)

    Tássia Pereira Alves

    2014-04-01

    Full Text Available Inclusion is a social process in school aims to change attitudes and to build a position to cover everyone without distinction. Thus, the objective was to analyze the representations of deaf students on their inclusion in physical education classes. It is qualitative, descriptive and analytical, attended eight deaf students from 2 public schools in a city in the countryside of Bahia. For data production, it was used a semi -structured interview, through the aid of an interpreter of Brazilian Sign Language (Libras, at the same time, it was translated by the interpreter and transcribed by the researchers. Data analysis used the technique of categorical content analysis. The inclusion of deaf people in physical education classes still failed to materialize and in fact, even having found some teachers with pedagogical actions that proved to be inclusive, yet they still leave many gaps, regarding satisfactory learning of students because they simply just integrate deaf students in the classroom. It is necessary that the school and the teacher ensure that the curriculum is accessible to them, so that they can contribute to the construction of citizenship, motor development, cognitive and social-emotional student.

  10. On Bivariate Generalized Exponential-Power Series Class of Distributions

    OpenAIRE

    Jafari, Ali Akbar; Roozegar, Rasool

    2015-01-01

    In this paper, we introduce a new class of bivariate distributions by compounding the bivariate generalized exponential and power-series distributions. This new class contains some new sub-models such as the bivariate generalized exponential distribution, the bivariate generalized exponential-poisson, -logarithmic, -binomial and -negative binomial distributions. We derive different properties of the new class of distributions. The EM algorithm is used to determine the maximum likelihood estim...

  11. 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; Hvid, C.S.; Lamberth, K.; Buus, S.; Brunak, Søren; Lund, Ole

    2004-01-01

    , 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...... MHC class II complex HLA-DR4(B1*0401). Prior identification of information-rich (anchor) positions in the binding motif is shown to improve the predictive performance of the Gibbs sampler. Similarly, a consensus solution obtained from an ensemble average over suboptimal solutions is shown to...... conventional alignment algorithm of ClustalW. The calculation demonstrates that the predictive performance of the Gibbs sampler is higher than that of ClustalW and in most cases also higher than that of the TEPITOPE method....

  12. Assessment of the efficacy of blended learning in an introductory pharmacy class

    Science.gov (United States)

    Munson, Christina Elizabeth

    Blended learning is the convergence between traditional face-to-face learning typically seen in a university setting and a computer-mediated learning environment, and is increasingly being seen as a viable alternative for learning instruction. Pharmaceutical calculations (PC) is a course taken by students in the first year in the school of pharmacy at the University of Kansas (KU SOP). One of the objectives of the PC class is that students are able to perform calculations with minimal error consistently. This requires repetitive drill which is a poor use of class time. By moving presentation of material online and using class time for small learning group problem solving as well as practice exams, the transformation of the course to a blended or hybrid course is assessed for efficacy and found to have student outcomes which are comparable to previous face-to-face (F2F) classes. As KU SOP expands it class sizes from 105 to ˜150 students and its campuses (building a satellite campus in Wichita, Kansas), being able to provide quality instruction at a reasonable cost is desirable. By redesigning PC to be a hybrid course, the need to hire additional instructors and/or increase available resources is minimized. Instructors remain for the large part on the main campus in Lawrence while students are learning at remote locations, a cost-effective measure for all parties involved. Using small learning groups (consisting of not more than 3 or 4 students) to work problems in PC was demonstrated to be an effective use of F2F class time in the fall semester, 2008 at KU. The class was taught by the same instructor in the fall of 2009 using blended learning as the class format. The current computer Learning Management System (LMS) in use at KU is Blackboard((c)2010). By using Blackboard to deliver lectures and have students work through tutorials to learn the material, class time was devoted to highly-focused problem solving. Due to unequal data distribution, the non

  13. Time to Confront Willis's Lads with a Ballet Class? A Case Study of Educational Orthodoxy and White Working-Class Boys

    Science.gov (United States)

    Ashley, Martin

    2009-01-01

    This is a retrospective study tracing the longer term effects on identity and aspiration of white working-class boys from an area of high social deprivation. The boys were members of an acclaimed boys' dance company and have been retrospectively interviewed as young men in their twenties. Documentary and film material dating from the time they…

  14. Statins: An undesirable class of aquatic contaminants?

    Science.gov (United States)

    Santos, Miguel M; Ruivo, Raquel; Lopes-Marques, Mónica; Torres, Tiago; de Los Santos, Carmen B; Castro, L Filipe C; Neuparth, Teresa

    2016-05-01

    Emerging pollutants, such as pharmaceuticals, may pose a considerable environment risk. Hypocholesterolaemic drugs such as statins are among the most prescribed human pharmaceuticals in western European countries. In vertebrates, this therapeutic class disrupts the cholesterol synthesis by inhibiting the enzyme 3-hydroxy-3-methyl-glutaryl-CoA reductase (HMGR), responsible for the limiting step in the mevalonate pathway. Recently, functional studies have shown that statins competitively inhibit HMGR in vertebrates and arthropods, two taxa that have diverged over 450 million years ago. Importantly, chronic simvastatin exposure disrupts crustacean reproduction and development at environmentally relevant concentrations. Hence, a fundamental question emerges: what is the taxonomic scope of statins-induced HMGR inhibition across metazoans? Here, we address this central question in a large sampling of metazoans using comparative genomics, homology modelling and molecular docking. Sequence alignment of metazoan HMGRs allowed the annotation of highly conserved catalytic, co-factor and substrate binding sites, including residues highjacked for statin binding. Furthermore, molecular docking shows that the catalytic domains of metazoan HMGRs are highly conserved regarding interactions, not only with HMG-CoA, but also with both simvastatin and atorvastatin, the top prescribed statins in Europe and USA. Hence, the data indicates that both statins are expected to competitively inhibit metazoan's HMGRs, and therefore all metazoan taxa might be at risk. The environmental relevance of these findings are discussed and research priorities established. We believe that the conceptual framework used in this study can be applied to other emerging pollutants and assist in the design of toxicity testing and risk assessment. PMID:26896816

  15. SnO2 Nanorods on ZnO Nanofibers: A New Class of Hierarchical Nanostructures Enabled by Electrospinning as Anode Material for High-Performance Lithium-Ion Batteries

    International Nuclear Information System (INIS)

    Highlights: • We have successfully fabricated the novel SnO2/ZnO11HNFs by a simple and controllable strategy. • The present synthetic strategy is controllable and can be further extended to prepare various heterostructure nanocomposites between two metal oxides. • The as-obtained SnO2/ZnO11HNFs exhibits outstanding cycle performance, anodic capacity and rate performance. - Abstract: The ZnO/SnO2 heterogeneous nanofibers (HNFs) have been prepared via an electrospinning method followed by calcination at 500 °C in air. XRD, BET, SEM, TEM and electrochemical measurements were performed to characterize the new material, including structure, morphology and electrochemical properties. The spacing between adjacent SnO2 nanorods on mesoporous ZnO nanofibers is about twice the diameter of each SnO2 nanorod. The SnO2/ZnO11 (molar ratio of Sn: Zn = 1:1) HNFs based electrodes exhibit excellent cycle performance and rate performance, which is attributed to the heterogeneous and mesoporous structure as well as the ultrafine ZnO NPs embedded in the HNFs matrix. Outstanding electrochemical performance as anode material for LIBs together with low cost, facile procedures and high reproducibility make the SnO2/ZnO HNFs have a prospect in the field of energy storage

  16. Alteration and long-term behaviour of different types of innovative materials for long-lived radionuclides confinement; Alteration et comportement a long terme de differentes classes de materiaux innovants pour le confinement des radionucleides a vie longue

    Energy Technology Data Exchange (ETDEWEB)

    Leturcq, G

    1998-09-29

    The present work is an experimental study on alteration mechanisms of synthetic and natural materials: aluminosilicate glasses, glass ceramics and Ti, Zr or P based ceramics. It is a part of CEA's study program on the immobilization of long- lived radionuclides and deals with chemical processes which control dissolution of amorphous and crystallized solids. The different aluminosilicate glasses studied are altered according to a process of hydrolysis of the bonds between the glass network formers; the activation energy of this reaction is about 60 kJ/mol. Alteration rates of all the glasses decrease by four orders of magnitude when the reaction progress increases. Kinetic laws based on the deviation from the thermodynamic equilibrium between leachate and the fresh solid cannot explain these great decreases. Alteration layers in the reactional interface seem to control the alteration kinetics by providing a passivation process. The chemical durability of the glass ceramics (zirconolite and titanite) improves by a factor of ten in regard to the primary glasses which were obtained by thermal treatment. Zirconium-titanate ceramics are altered only slightly by water. The altered mass corresponds to a few atomic layers only. Steady stases are quickly observed. On the basis of thermodynamic calculations, they are not correlated with saturation between the leachate and primary zirconium-titanate phases. Alteration here also ceases due to the development of a passivating layer. Models aiming at studying the chemical durability of zirconium-titanate ceramics under conditions more representative of a clayey site of geological storage were carried out. The results of the interactions of these ceramics with clays, at 708 deg.C, show clearly that there is no modification of the process of alteration, compared to the simpler pure water systems. Thus, perovskite and zirconolite do not deteriorate under these conditions. (author)

  17. Stress relief cracking of A533B Class 1 and A508 Class 3 steels

    International Nuclear Information System (INIS)

    The stress relief cracking (SRC) susceptibility of A533B Class 1 and A508 Class 3 steels with simulated heat affected zone (HAZ) microstructures has been assessed using a constant displacement stress relaxation test. Notched four point bend samples were loaded to various levels to simulate a range of residual stresses and the subsequent load-relaxation and crack growth behaviour determined during a heating cycle typical of a post-weld-heat-treatment (1000C h-1). The cracking response and the micromechanisms of SRC were determined by metallographic and surface analytical techniques. The validity of the test method was assessed by conducting comparative tests on the coarse-grained HAZ microstructure of a C-Mn steel which was known to have a very low susceptibility to SRC

  18. On Ramsey properties of classes with forbidden trees

    CERN Document Server

    Foniok, Jan

    2011-01-01

    Let $\\F$ be a set of relational trees and let $\\Forbh(\\F)$ be the class of all structures that admit no homomorphism from any tree in $\\F$; all this happens over a fixed finite relational signature $\\sigma$. There is a natural way to expand $\\Forbh(\\F)$ by unary relations to an amalgamation class. This expanded class, enhanced with a linear ordering, has the Ramsey property.

  19. ORTHOGNATIC SURGICAL TREATMENT OF SKELETAL CLASS III MALOCLUSION: CASE REPORT

    OpenAIRE

    GÜNGÖR, AHMET YALÇIN; Turkkahraman, Hakan; Baykul, Timucin; Aydın, Asım

    2012-01-01

    In this case report a case is presented with skeletal class III malocclusion which were treated with proper planned orthognatic surgery and orthodontic treatment. Our patient was a girl with 16 years, 3 months of chronologic and Ru period of skeletal age. A concave soft tissue profile and Class III molar relation was detected in extraoral and intraoral examination. Cephalometric evaluation revealed a significant Class III skeletal discrepancy (ANBº= -6). Presurgical orthodontics involved deco...

  20. Exploring the diversity of Jupiter-class planets.

    Science.gov (United States)

    Fletcher, Leigh N; Irwin, Patrick G J; Barstow, Joanna K; de Kok, Remco J; Lee, Jae-Min; Aigrain, Suzanne

    2014-04-28

    Of the 900+ confirmed exoplanets discovered since 1995 for which we have constraints on their mass (i.e. not including Kepler candidates), 75% have masses larger than Saturn (0.3 MJ), 53% are more massive than Jupiter and 67% are within 1 AU of their host stars. When Kepler candidates are included, Neptune-sized giant planets could form the majority of the planetary population. And yet the term 'hot Jupiter' fails to account for the incredible diversity of this class of astrophysical object, which exists on a continuum of giant planets from the cool jovians of our own Solar System to the highly irradiated, tidally locked hot roasters. We review theoretical expectations for the temperatures, molecular composition and cloud properties of hydrogen-dominated Jupiter-class objects under a variety of different conditions. We discuss the classification schemes for these Jupiter-class planets proposed to date, including the implications for our own Solar System giant planets and the pitfalls associated with compositional classification at this early stage of exoplanetary spectroscopy. We discuss the range of planetary types described by previous authors, accounting for (i) thermochemical equilibrium expectations for cloud condensation and favoured chemical stability fields; (ii) the metallicity and formation mechanism for these giant planets; (iii) the importance of optical absorbers for energy partitioning and the generation of a temperature inversion; (iv) the favoured photochemical pathways and expectations for minor species (e.g. saturated hydrocarbons and nitriles); (v) the unexpected presence of molecules owing to vertical mixing of species above their quench levels; and (vi) methods for energy and material redistribution throughout the atmosphere (e.g. away from the highly irradiated daysides of close-in giants). Finally, we discuss the benefits and potential flaws of retrieval techniques for establishing a family of atmospheric solutions that reproduce the

  1. On a General Class of Trigonometric Functions and Fourier Series

    Science.gov (United States)

    Pavao, H. Germano; Capelas de Oliveira, E.

    2008-01-01

    We discuss a general class of trigonometric functions whose corresponding Fourier series can be used to calculate several interesting numerical series. Particular cases are presented. (Contains 4 notes.)

  2. Managing changes of location classes of gas pipelines

    Energy Technology Data Exchange (ETDEWEB)

    Cunha, Sergio B.; Sousa, Antonio Geraldo de [PETROBRAS Transporte S.A. (TRANSPETRO), Rio de Janeiro, RJ (Brazil)

    2009-12-19

    Most of the gas pipeline design codes utilize a class location system, where the design safety factor and the hydrostatic test factor are determined according to the population density in the vicinities of the pipeline route. Consequently, if an operator is requested or desires to maintain an existing gas pipeline in compliance with its design code, it will reduce the operational pressure or replace pipe sections to increase the wall thickness whenever a change in location class takes place. This article introduces an alternative methodology to deal with changes in location classes of gas pipelines. Initially, selected codes that utilize location class systems are reviewed. Afterwards, a model for the area affected by an ignition following a natural gas pipeline leak is described. Finally, a methodology to determine the MAOP and third part damage mitigation measures for gas transport pipelines that underwent changes in location class is presented. (author)

  3. How 'core' are motor timing difficulties in ADHD? A latent class comparison of pure and comorbid ADHD classes.

    Science.gov (United States)

    van der Meer, Jolanda M J; Hartman, Catharina A; Thissen, Andrieke J A M; Oerlemans, Anoek M; Luman, Marjolein; Buitelaar, Jan K; Rommelse, Nanda N J

    2016-04-01

    Children with attention-deficit/hyperactivity disorder (ADHD) have motor timing difficulties. This study examined whether affected motor timing accuracy and variability are specific for ADHD, or that comorbidity with autism spectrum disorders (ASD) contributes to these motor timing difficulties. An 80-trial motor timing task measuring accuracy (μ), variability (σ) and infrequent long response times (τ) in estimating a 1-s interval was administered to 283 children and adolescents (8-17 years) from both a clinic and population based sample. They were divided into four latent classes based on the SCQ and CPRS-R:L data. These classes were: without behavioral problems 'Normal-class' (n = 154), with only ADHD symptoms 'ADHD-class' (n = 49), and two classes with both ASD and ADHD symptoms; ADHD(+ASD)-class (n = 39) and ASD(+ADHD)-class (n = 41). The pure ADHD-class did not deviate from the Normal class on any of the motor timing measures (mean RTs 916 and 925 ms, respectively). The comorbid ADHD(+ASD) and ASD(+ADHD) classes were significantly less accurate (more time underestimations) compared to the Normal class (mean RTs 847 and 870 ms, respectively). Variability in motor timing was reduced in the younger children in the ADHD(+ASD) class, which may reflect a tendency to rush the tedious task. Only patients with more severe behavioral symptoms show motor timing deficiencies. This cannot merely be explained by high ADHD severity with ASD playing no role, as ADHD symptom severity in the pure ADHD-class and the ASD(+ADHD) class was highly similar, with the former class showing no motor timing deficits. PMID:26154019

  4. The dynamics of absence behaviour: Interrelations between absence from class and absence in class

    DEFF Research Database (Denmark)

    Jonasson, Charlotte

    2011-01-01

    absence is best prevented. Sample: Fieldwork was conducted at a vocational school containing 850 students. In this particular study, 24 student interviews were used in combination with interviews from four teachers and three school managers. Design and methods: The study is an ethnographic case study of a...... single school conducted over a continuous six-month period. It used participant observation followed by semi-structured interviews and school documents. Results: Findings suggest that student absence consists of interrelated forms of absence behaviour that have specific consequences for student...... the social practice of students, teachers and school managers. Evaluations of both absence from class and absence in class are important for understanding how absence behaviour can be identified and prevented....

  5. A Harvest of Learning for a Multiage Class.

    Science.gov (United States)

    Chase, Penelle

    1995-01-01

    For the past four years, a multiage class in Maine has been involved in a pumpkin-growing and -marketing enterprise--a project involving real work and problem solving. Begun with a seed grant, the project raises money for field trips and nonessential teaching materials. Working cooperatively forges strong bonds among children, teachers, and…

  6. WORKING WITH ALKALINE MATERIALS TO ACHIEVE A CLASS B, CLASS A, AND/OR A BIOSOLIDS THAT DOES NOT ATTRACT VECTORS

    Science.gov (United States)

    This workshop presentation begins with a discussion of the use of lime and other alkaline materials from the very earliest times to the present for killing bacteria, viruses and parasites and for controlling odors in wastewaters and sludge. It answers the question "How did EPA ar...

  7. Integration of Nutrition Education Classes Into English As Second Language Classes For Refugees

    OpenAIRE

    Gunnell, Sarah

    2012-01-01

    Recently resettled refugees are at high risk for food insecurity and its health consequences. This observational study evaluated the effectiveness of integrating nutrition lessons into English as a Second Language (ESL) classes at a work-site training center for refugees. The lessons focused on making healthy choices with a limited budget. Through the assistance of ESL teachers, nutrition educator assistants (NEAs) from the Supplemental Nutrition Assistance Program (SNAP) taught nutrition les...

  8. From mapping class groups to automorphism groups of free groups

    DEFF Research Database (Denmark)

    Wahl, Nathalie

    2005-01-01

    We show that the natural map from the mapping class groups of surfaces to the automorphism groups of free groups, induces an infinite loop map on the classifying spaces of the stable groups after plus construction. The proof uses automorphisms of free groups with boundaries which play the role of...... mapping class groups of surfaces with several boundary components....

  9. Class analysis and the reorientation of class theory: the case of persisting differentials in educational attainment. 1996.

    Science.gov (United States)

    Goldthorpe, John H

    2010-01-01

    In class analysis the main regularities that have been established by empirical research are not ones of long-term class formation or decomposition, as envisaged in Marxist or liberal theory, but rather ones that exhibit the powerful resistance to change of class relations and associated life-chances and patterns of social action. If these regularities are to be explained, theory needs to be correspondingly reoriented, and must abandon functionalist and teleological assumptions in favour of providing more secure micro-foundations. This argument is developed and illustrated in the course of an attempt to apply rational action theory to the explanation of persisting class differentials in educational attainment. PMID:20092500

  10. Classes of source pairs in interference and diffraction

    International Nuclear Information System (INIS)

    A description of interference and diffraction based on the concept of class of source pairs is presented. It is the set of pairs of sources whose contributions to the interference or diffraction patterns exhibit the same phase difference. Each class of source pairs provides a specific cosine-like modulation on the intensity distribution of pattern, in such a way that the set provides an expansion of the intensity distribution of the pattern in an orthogonal basis. From this point of view, the classes of source pairs are the effective elementary sources for those intensity distributions. The characteristics of the classes of source pairs can be accurately determined by Fourier transforming the intensity distribution of the patterns. The central value of this Fourier spectrum is related to the number of individual sources. The remaining values will provide two crucial descriptors of the classes: their positions on the Fourier transform domain will be corresponding to the separation vector of the class of pairs for wave front splitting interferometers (WSI) and diffraction, or the time delay for amplitude splitting interferometers (ASI), and their heights will be proportional to their populations. The concept was also applied to Fraunhofer and Fresnel diffraction, but now the classes of source pairs constitute a continuous set instead of the discrete sets in interference. However, the set of classes can also be determined by Fourier analysis. (author)

  11. CLASSING APPROACH TO ANALYZING THE INVESTMENT SPACE OF SILK INDUSTRY OF UZBEKISTAN

    OpenAIRE

    Madjidov, Shakhrukh; Ibragimova, Sabokhat

    2015-01-01

    In the article the results of verification were brought which were dedicated for cluster approach and analyzing the investment space of silk industry of Uzbekistan. In particular the purpose of investment’s direction to the main capital of silk industry in corresponding class while proceeding from closeness to manual forces and raw material resources.

  12. A New Class of Electrically Tunable Metamaterial Terahertz Modulators

    CERN Document Server

    Yan, Rusen; Liu, Lei; Jena, Debdeep; Xing, Huili Grace

    2012-01-01

    Switchable metamaterials offer unique solutions for efficiently manipulating electromagnetic waves, particularly for terahertz waves, which has been difficult since naturally occurring materials rarely respond to terahertz frequencies controllably. However, few terahertz modulators demonstrated to date exhibit simultaneously low attenuation and high modulation depth. In this letter we propose a new class of electrically-tunable terahertz metamaterial modulators employing metallic frequency-selective-surfaces (FSS) in conjunction with capacitively-tunable layers of electrons, promising near 100% modulation depth and < 15% attenuation. The fundamental departure in our design from the prior art is tuning enabled by self-gated electron layers that is independent from the metallic FSS. Our proposal is applicable to all possible electrically tunable elements including graphene, Si, MoS2, oxides etc, thus opening up myriad opportunities for realizing high performance switchable metamaterials over an ultra-wide te...

  13. Analysis of College Classes Based on U-CLASS System Using Personal Mobile Nodes

    OpenAIRE

    Chonggun Kim; Jeongmi Kim; Hohwan Park; Ilkyu Ha

    2015-01-01

    The increase in mobile communications has led to advanced educational methods and technologies through accepting new technologies. A lot of studies have tried to overcome temporal and spatial limits on using personal mobile devices and have tried to increase learning effectiveness using various efficient educational methods. In this paper, U-CLASS, an interactive learning management system that provides interactive communications between a professor and students, is proposed and implemented. ...

  14. Work-life balance/imbalance: the dominance of the middle class and the neglect of the working class.

    Science.gov (United States)

    Warren, Tracey

    2015-12-01

    The paper was stimulated by the relative absence of the working class from work-life debates. The common conclusion from work-life studies is that work-life imbalance is largely a middle-class problem. It is argued here that this classed assertion is a direct outcome of a particular and narrow interpretation of work-life imbalance in which time is seen to be the major cause of difficulty. Labour market time, and too much of it, dominates the conceptualization of work-life and its measurement too. This heavy focus on too much labour market time has rendered largely invisible from dominant work-life discourses the types of imbalance that are more likely to impact the working class. The paper's analysis of large UK data-sets demonstrates a reduction in hours worked by working-class men, more part-time employment in working-class occupations, and a substantial growth in levels of reported financial insecurity amongst the working classes after the 2008-9 recession. It shows too that economic-based work-life imbalance is associated with lower levels of life satisfaction than is temporal imbalance. The paper concludes that the dominant conceptualization of work-life disregards the major work-life challenge experienced by the working class: economic precarity. The work-life balance debate needs to more fully incorporate economic-based work-life imbalance if it is to better represent class inequalities. PMID:26487574

  15. Groupoid extensions of mapping class representations for bordered surfaces

    DEFF Research Database (Denmark)

    Andersen, Jørgen Ellegaard; Bene, Alex; Penner, Robert

    The mapping class group of a surface with one boundary component admits numerous interesting representations including as a group of automorphisms of a free group and as a group of symplectic transformations. Insofar as the mapping class group can be identified with the fundamental group of Riema...

  16. 7 CFR 1007.40 - Classes of utilization.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Classes of utilization. 1007.40 Section 1007.40 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing... Handling Classification of Milk § 1007.40 Classes of utilization. See § 1000.40....

  17. 7 CFR 1126.40 - Classes of utilization.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Classes of utilization. 1126.40 Section 1126.40 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing... Handling Classification of Milk § 1126.40 Classes of utilization. See § 1000.40....

  18. 7 CFR 1033.40 - Classes of utilization.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Classes of utilization. 1033.40 Section 1033.40 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing... Handling Classification of Milk § 1033.40 Classes of utilization. See § 1000.40....

  19. 7 CFR 1001.40 - Classes of utilization.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Classes of utilization. 1001.40 Section 1001.40 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing... Handling Classification of Milk § 1001.40 Classes of utilization. See § 1000.40....

  20. 7 CFR 1131.40 - Classes of utilization.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Classes of utilization. 1131.40 Section 1131.40 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing... Handling Classification of Milk § 1131.40 Classes of utilization. See § 1000.40....

  1. 7 CFR 1124.40 - Classes of utilization.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Classes of utilization. 1124.40 Section 1124.40 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing... Regulating Handling Classification of Milk § 1124.40 Classes of utilization. See § 1000.40....

  2. 7 CFR 1000.40 - Classes of utilization.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Classes of utilization. 1000.40 Section 1000.40 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing... Classification of Milk § 1000.40 Classes of utilization. Except as provided in § 1000.42, all skim milk...

  3. 7 CFR 1032.40 - Classes of utilization.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Classes of utilization. 1032.40 Section 1032.40 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing... Handling Classification of Milk § 1032.40 Classes of utilization. See § 1000.40....

  4. 7 CFR 1006.40 - Classes of utilization.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Classes of utilization. 1006.40 Section 1006.40 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing... Handling Classification of Milk § 1006.40 Classes of utilization. See § 1000.40....

  5. 7 CFR 1005.40 - Classes of utilization.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Classes of utilization. 1005.40 Section 1005.40 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing... Regulating Handling Classification of Milk § 1005.40 Classes of utilization. See § 1000.40....

  6. 7 CFR 1030.40 - Classes of utilization.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Classes of utilization. 1030.40 Section 1030.40 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing... Regulating Handling Classification of Milk § 1030.40 Classes of utilization. See § 1000.40....

  7. The Intersections of Social Class and the Transition to Adulthood

    Science.gov (United States)

    Furstenberg, Frank F.

    2008-01-01

    This article provides an introduction to and overview of the literature on how the transition to adulthood is shaped by social class. It brings together two strands of literature. The first reviews why and how the third decade of life has been reshaped by later and longer education. The second considers how the social class position of young…

  8. Race/class : Jamaica's discourse of heritable identity

    Directory of Open Access Journals (Sweden)

    Diane J. Austin-Broos

    1994-07-01

    Full Text Available Argues that Jamaican notions of 'race' and 'class' can be rendered as a discourse of heritable biological and environmental identity. There has been a movement in the meaning of colour categories from an emphasis on biology, to a greater emphasis on environment. This transition has been encouraged by the emergence of class as a 20th-c. idiom.

  9. Principles of Food Science Class Sheds Light on Chemistry

    Science.gov (United States)

    Ward, Janet

    2004-01-01

    Many students are curious about the steps in food preparation. As a result of such experiences, the author of this article began to incorporate science demonstrations into food preparation classes. She conducted research, developed resources, and piloted the "Principles of Food Science" class over the next 6 years. "Principles of Food Science"…

  10. Nonproliferation Graduate Fellowship Program, Annual Report, Class of 2012

    Energy Technology Data Exchange (ETDEWEB)

    McMakin, Andrea H.

    2013-09-23

    This 32-pp annual report/brochure describes the accomplishments of the Class of 2012 of the Nonproliferation Graduate Fellowship Program (the last class of this program), which PNNL administers for the National Nuclear Security Administration. The time period covers Sept 2011 through June 2013.

  11. 78 FR 37114 - Self-Regulation of Class II Gaming

    Science.gov (United States)

    2013-06-20

    ... the issuance of a certificate for tribal self-regulation of Class II gaming. 78 FR 20236, April 4... National Indian Gaming Commission 25 CFR Part 518 RIN 3141-AA44 Self-Regulation of Class II Gaming AGENCY: National Indian Gaming Commission, Department of the Interior. ACTION: Final rule; technical and...

  12. Prime valued polynomials and class numbers of quadratic fields

    Directory of Open Access Journals (Sweden)

    Richard A. Mollin

    1990-01-01

    Full Text Available It is the purpose of this paper to give a survey of the relationship between the class number one problem for real quadratic fields and prime-producing quadratic polynomials; culminating in an overview of the recent solution to the class number one problem for real quadratic fields of Richaud-Degert type. We conclude with new conjectures, questions and directions.

  13. On the effective and automatic enumeration of polynomial permutation classes

    OpenAIRE

    Homberger, Cheyne; Vatter, Vince

    2013-01-01

    We describe an algorithm, implemented in Python, which can enumerate any permutation class with polynomial enumeration from a structural description of the class. In particular, this allows us to find formulas for the number of permutations of length n which can be obtained by a finite number of block sorting operations (e.g., reversals, block transpositions, cut-and-paste moves).

  14. Geometric properties of composition operators belonging to Schatten classes

    OpenAIRE

    Yongsheng Zhu

    2001-01-01

    We investigate the connection between the geometry of the image domain of an analytic function mapping the unit disk into itself and the membership of the composition operator induced by this function in the Schatten classes. The purpose is to provide solutions to Lotto's conjectures and show a new compact composition operator which is not in any of the Schatten classes.

  15. 19 CFR 19.1 - Classes of customs warehouses.

    Science.gov (United States)

    2010-04-01

    ... 19 Customs Duties 1 2010-04-01 2010-04-01 false Classes of customs warehouses. 19.1 Section 19.1 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND SECURITY; DEPARTMENT OF THE TREASURY CUSTOMS WAREHOUSES, CONTAINER STATIONS AND CONTROL OF MERCHANDISE THEREIN § 19.1 Classes...

  16. Properties of oxygen free copper (ASTM-F68-Class 1) for particle accelerators

    International Nuclear Information System (INIS)

    In vacuum, materials like stainless steel, aluminum and copper desorb gas molecules. Oxygen free copper (OFC) is widely used for a material of vacuum components. Some components especially for a particle accelerator like electron tubes, waveguides, accelerator cavities have been troubled with rapid pressure rise, discharge breakdown and other vacuum related accidents caused by the enhanced gas desorption in a 'hot' vacuum. Vacuum degassing process applied to a continuous casting plant successfully reduces the content of gases such as hydrogen and oxygen. It is confirmed that the vacuum degassed OFC shows almost no porosity in itself, and thus satisfies ASTM (American Society for Testing and Materials)-F68 specification of Class 1, the highest grade OFC for electron devices. This material also shows less gas desorption yield in some measurements that simulate a dynamic gas desorption likely occurred in accelerators, and higher breakdown field than ordinary OFC. Therefore, OFC-Class 1 is the best copper material for the particle accelerator. (author)

  17. Material models of dark energy

    CERN Document Server

    Pearson, Jonathan A

    2014-01-01

    We review and develop a new class of "dark energy" models, in which the relativistic theory of solids is used to construct material models of dark energy. These are models which include the effects of a continuous medium with well defined physical properties at the level of linearized perturbations. The formalism is constructed for a medium with arbitrary symmetry, and then specialised to isotropic media (which will be the case of interest for the majority of cosmological applications). We develop the theory of relativistic isotropic viscoelastic media whilst keeping in mind that we ultimately want to observationally constrain the allowed properties of the material model. We do this by obtaining the viscoelastic equations of state for perturbations (the entropy and anisotropic stress), as well as identifying the consistent corner of the theory which has constant equation of state parameter $\\dot{w}=0$. We also connect to the non-relativistic theory of solids, by identifying the two quadratic invariants that a...

  18. QUALITATIVE STUDY OF CAVITATED BIFURCATION FOR A CLASS OF INCOMPRESSIBLE GENERALIZED NEO-HOOKEAN SPHERES

    Institute of Scientific and Technical Information of China (English)

    YUAN Xue-gang; ZHU Zheng-you

    2005-01-01

    The problem of spherical cavitated bifurcation was examined for a class of incompressible generalized neo-Hookean materials, in which the materials may be viewed as the homogeneous incompressible isotropic neo-Hookean material with radial perturbations.The condition of void nucleation for this problem was obtained. In contrast to the situation for a homogeneous isotropic neo-Hookean sphere, it is shown that not only there exists a secondary turning bifurcation point on the cavitated bifurcation solution which bifurcates locally to the left from trivial solution, and also the critical load is smaller than that for the material with no perturbations, as the parameters belong to some regions. It is proved that the cavitated bifurcation equation is equivalent to a class of normal forms with single-sided constraints near the critical point by using singularity theory. The stability of solutions and the actual stable equilibrium state were discussed respectively by using the minimal potential energy principle.

  19. Local invariants for a class of mixed states

    International Nuclear Information System (INIS)

    We investigate the equivalence of quantum states under local unitary transformations. A complete set of invariants under local unitary transformations is presented for a class of mixed states. It is shown that two states in this class are locally equivalent if and only if all these invariants have equal values for them. (orig.)

  20. A Revised Class Play Method of Peer Assessment.

    Science.gov (United States)

    Masten, Ann S.; And Others

    1985-01-01

    Revised Class Play (RCP) was presented as a measure of peer reputation designed to improve the assessment of social competence as well as the psychometric properties of class play method. Administered to third through sixth graders three test dimensions were revealed: sociability-leadership, aggressive-disruptive, and sensitive-isolated. Data…

  1. More Classes of Complete Permutation Polynomials over $\\F_q$

    OpenAIRE

    Wu, Gaofei; Li, Nian; Helleseth, Tor; Zhang, Yuqing

    2013-01-01

    In this paper, by using a powerful criterion for permutation polynomials given by Zieve, we give several classes of complete permutation monomials over $\\F_{q^r}$. In addition, we present a class of complete permutation multinomials, which is a generalization of recent work.

  2. Does a tetracycline resistance determinant of class N exist?

    OpenAIRE

    Horaud, T; Delbos, F; Pepper, K

    1990-01-01

    pMV120 was reported to carry the tetracycline resistance (Tcr) determinant of class N. We obtained tetracycline-susceptible transconjugants harboring plasmids with restriction enzyme profiles indistinguishable from those of pMV120 isolated from tetracycline-resistant clones. We conclude that pMV120 is a cryptic plasmid and that class N of Tcr determinants does not exist.

  3. The Rise of Class Culture Theory in Educational Anthropology

    Science.gov (United States)

    Foley, Douglas

    2010-01-01

    This article chronicles how the ideas of neo-Weberians, Marxists, feminists, and critical race thinkers have merged to create a new cultural production or class culture paradigm of schooling. Reviews of recent ethnographic work illustrates how the articulations among class, race, gender, and sexual identity practices in schools are studied without…

  4. Invariants for a Class of Nongeneric Three-qubit States

    CERN Document Server

    Sun, B Z; Sun, Bao-Zhi; Fei, Shao-Ming

    2006-01-01

    We investigate the equivalence of quantum states under local unitary transformations. A complete set of invariants under local unitary transformations is presented for a class of non-generic three-qubit mixed states. It is shown that two such states in this class are locally equivalent if and only if all these invariants have equal values for them.

  5. Selfsimilarity in a Class of Quadratic-Quasiperiodic Chains

    Science.gov (United States)

    Kaneko, Masanobu; Odagaki, Takashi

    1993-04-01

    We prove that quasiperiodic chains associated with a class of quadratic irrational numbers have an inflation symmetry and can be generated from a regular chain by a hyperinflation. We devise the explicit method to find the hyperinflation symmetry and discuss the properties of such a class of quasiperiodic sequences.

  6. 22 CFR 40.9 - Classes of inadmissible aliens.

    Science.gov (United States)

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Classes of inadmissible aliens. 40.9 Section 40.9 Foreign Relations DEPARTMENT OF STATE VISAS REGULATIONS PERTAINING TO BOTH NONIMMIGRANTS AND... inadmissible aliens. Subparts B through L describe classes of inadmissible aliens who are ineligible to...

  7. 47 CFR 80.207 - Classes of emission.

    Science.gov (United States)

    2010-10-01

    ... Register citations affecting § 80.207, see the List of CFR Sections Affected, which appears in the Finding... 47 Telecommunication 5 2010-10-01 2010-10-01 false Classes of emission. 80.207 Section 80.207... MARITIME SERVICES General Technical Standards § 80.207 Classes of emission. (a) Authorization to...

  8. Input, Output, and Negotiation of Meaning in Spanish Conversation Classes

    Science.gov (United States)

    Rondon-Pari, Graziela

    2014-01-01

    This research study is based on the analysis of speech in three Spanish conversation classes. Research questions are: What is the ratio of English and Spanish spoken in class? Is classroom speech more predominant in students or the instructor? And, are teachers' beliefs in regards to the use of English and Spanish consistent with their…

  9. 19 CFR 151.25 - Mixing classes of sugar.

    Science.gov (United States)

    2010-04-01

    ... 19 Customs Duties 2 2010-04-01 2010-04-01 false Mixing classes of sugar. 151.25 Section 151.25... TREASURY (CONTINUED) EXAMINATION, SAMPLING, AND TESTING OF MERCHANDISE Sugars, Sirups, and Molasses § 151.25 Mixing classes of sugar. No regulations relative to the weighing, taring, sampling,...

  10. Uniqueness of source for a class of semilinear elliptic equations

    International Nuclear Information System (INIS)

    Uniqueness of source is proved for an important class of semilinear elliptic partial differential equations useful for identification of doping profiles in semiconductor devices and for modeling of ion channels in biological systems

  11. Joining of dissimilar materials

    Science.gov (United States)

    Tucker, Michael C; Lau, Grace Y; Jacobson, Craig P

    2012-10-16

    A method of joining dissimilar materials having different ductility, involves two principal steps: Decoration of the more ductile material's surface with particles of a less ductile material to produce a composite; and, sinter-bonding the composite produced to a joining member of a less ductile material. The joining method is suitable for joining dissimilar materials that are chemically inert towards each other (e.g., metal and ceramic), while resulting in a strong bond with a sharp interface between the two materials. The joining materials may differ greatly in form or particle size. The method is applicable to various types of materials including ceramic, metal, glass, glass-ceramic, polymer, cermet, semiconductor, etc., and the materials can be in various geometrical forms, such as powders, fibers, or bulk bodies (foil, wire, plate, etc.). Composites and devices with a decorated/sintered interface are also provided.

  12. Methods of materiality

    DEFF Research Database (Denmark)

    Aagaard, Jesper; Matthiesen, Noomi

    2016-01-01

    researchers should start paying attention to the material world (consisting of both human bodies and material objects) and what it means for how people live their lives. It is argued that this can be done by incorporating the concept of material presence to capture embodied and material layers of existence......, and the method of participant observation is suggested as a viable approach to achieve this end. An empirical example of how authority is produced in a parent-teacher conference, not only through language but also through material objects and embodied being, is then presented. The article concludes by...... suggesting practical guidelines for incorporating attention to materiality in qualitative research....

  13. Impact of Class Lecture Webcasting on Attendance and Learning

    Science.gov (United States)

    Traphagan, Tomoko; Kucsera, John V.; Kishi, Kyoko

    2010-01-01

    The present study investigated the impact of class lecture webcasts on students' attendance and learning. The research design employed four data collection methods in two class sections--one with webcast access and another without--of the same course taught by the same instructors. Results indicated the following four major findings. (1) The…

  14. 12 CFR 931.1 - Classes of capital stock.

    Science.gov (United States)

    2010-01-01

    ... 12 Banks and Banking 7 2010-01-01 2010-01-01 false Classes of capital stock. 931.1 Section 931.1 Banks and Banking FEDERAL HOUSING FINANCE BOARD FEDERAL HOME LOAN BANK RISK MANAGEMENT AND CAPITAL STANDARDS FEDERAL HOME LOAN BANK CAPITAL STOCK § 931.1 Classes of capital stock. The authorized...

  15. A new class of generalized Fibonacci unimodal maps

    International Nuclear Information System (INIS)

    We study a class of unimodal maps with generalized Fibonacci combinatorics in terms of generalized renormalization. This class is different from the ‘Fibonacci-like’ one considered by Bruin. It is proved that the map has no absolutely continuous invariant probability measure, provided that the critical order is large enough. (paper)

  16. Standardization of transportation classes for object-oriented deployment simulations.

    Energy Technology Data Exchange (ETDEWEB)

    Burke, J. F., Jr.; Howard, D. L.; Jackson, J.; Macal, C. M.; Nevins, M. R.; Van Groningen, C. N.

    1999-07-30

    Many recent efforts to integrate transportation and deployment simulations, although beneficial, have lacked a feature vital for seamless integration: a common data class representation. It is an objective of the Department of Defense (DoD) to standardize all classes used in object-oriented deployment simulations by developing a standard class attribute representation and behavior for all deployment simulations that rely on an underlying class representation. The Extensive Hierarchy and Object Representation for Transportation Simulations (EXHORT) is a collection of three hierarchies that together will constitute a standard and consistent class attribute representation and behavior that could be used directly by a large set of deployment simulations. The first hierarchy is the Transportation Class Hierarchy (TCH), which describes a significant portion of the defense transportation system; the other two deal with infrastructure and resource classes. EXHORT will allow deployment simulations to use the same set of underlying class data, ensure transparent exchanges, reduce the effort needed to integrate simulations, and permit a detailed analysis of the defense transportation system. This paper describes EXHORT's first hierarchy, the TCH, and provides a rationale for why it is a helpful tool for modeling major portions of the defense transportation system.

  17. Effects of Behavioral and Social Class Information on Social Judgment.

    Science.gov (United States)

    Baron, Reuben M.; And Others

    1995-01-01

    Investigated the role of disconfirming behavioral information and the limits on social class schema effects. Using a Bayesian model of social perception, it was found that unambiguous, relevant stimulus information influenced judgments. Although social class information did not affect relevant stimulus information, it did sway judgments in…

  18. Class Attendance and Performance in Principles of Economics

    Science.gov (United States)

    Cohn, Elchanan; Johnson, Eric

    2006-01-01

    A sample of 347 students, enrolled in principles of economics classes during the period 1997-2001, is used to examine the relation between class attendance and student performance on examinations. Among the questions examined are: Is attendance related to performance, with and without controls for other factors? Do only substantial levels of…

  19. Sub-classes and evolution stability of Wolfram's classesin the total-rule cellular automata

    Institute of Scientific and Technical Information of China (English)

    YAN Guangwu; TIAN Feng; DONG Yinfeng

    2004-01-01

    In this paper, we propose a concept of sub-classes and its evolution stability for the Wolfram's classes. Firstly, we obtain the sub-classes of the Wolfram's class IV, gene-piece of these sub-classes and their existing circumstance. Secondly, we introduce a new concept, the evolution stability, for the Wolfram's classes and sub-classes of Wolfram's class IV. Lastly, we find that Wolfram's classes I, II, and III have the evolution stability, but sub-classes of the Wolfram's class IV have not the evolution stability for the total rule cellular automata.

  20. Modelling of anisotropic compact star of emending class one

    CERN Document Server

    Bhar, Piyali; Manna, Tuhina

    2016-01-01

    In the present article, we have constructed static anisotropic compact star models of Einstein field equations for the spherical symmetric metric of embedding class one. By assuming the particular form of metric function $\

  1. Receiver operating characteristic analysis under tree orderings of disease classes.

    Science.gov (United States)

    Wang, Dan; Attwood, Kristopher; Tian, Lili

    2016-05-20

    Receiver operating characteristic (ROC) curve and its summary statistics (e.g., the area under curve (AUC)) are commonly used to evaluate the diagnostic accuracy for disease processes with binary classification. The ROC curve has been extended to ROC surface for scenarios with three ordinal classes or to hyper-surface for scenarios with more than three classes. For classifier under tree or umbrella ordering in which the marker measurement for one class is lower or higher than those for the other classes, the commonly adopted diagnostic measures are the naive AUC (NAUC) based on a pooled class of all the unordered classes and the umbrella volume (UV) based on the concept of volume under surface. However, both NAUC and UV have some limitations. For example, NAUC depends on the sampling weights for all the classes in population, and UV has only been introduced for three-class settings. In this article, we initiate the idea of a new ROC framework for tree or umbrella ordering (denoted as TROC) and propose the area under TROC curve (denoted as TAUC) as an appropriate diagnostic measure. The proposed TROC and TAUC share many nice features with the traditional ROC and AUC. Both parametric and nonparametric approaches are explored to construct the confidence interval estimation of TAUC. The performances of these methods are compared in simulation studies under a variety settings. At the end, the proposed methods are applied to a published microarray data set. Copyright © 2015 John Wiley & Sons, Ltd. PMID:26678355

  2. 75 FR 13670 - Amendment of Class E Airspace; Gadsden, AL

    Science.gov (United States)

    2010-03-23

    ... direct final rule with a request for comments in the Federal Register on December 29, 2009 (74 FR 68667... Federal Aviation Administration 14 CFR Part 71 Amendment of Class E Airspace; Gadsden, AL AGENCY: Federal... December 29, 2009 that amends Class E airspace at Northeast Alabama Regional, Gadsden, AL. DATES:...

  3. 75 FR 4270 - Modification of Class E Airspace; Anniston, AL

    Science.gov (United States)

    2010-01-27

    ... direct final rule with a request for comments in the Federal Register on October 28, 2009 (74 FR 55449... Federal Aviation Administration 14 CFR Part 71 Modification of Class E Airspace; Anniston, AL AGENCY... October 28, 2009 that modifies the Class E airspace at Anniston Metropolitan Airport, Anniston, AL....

  4. 75 FR 20773 - Establishment of Class E Airspace; Jackson, AL

    Science.gov (United States)

    2010-04-21

    ... final rule with a request for comments in the Federal Register on December 7, 2009 (74 FR 63973), Docket... Federal Aviation Administration 14 CFR Part 71 Establishment of Class E Airspace; Jackson, AL AGENCY... December 7, 2009 that establishes Class E airspace at Jackson Muni, Jackson, AL. DATES: Effective...

  5. Quality Differences and Price Responsiveness of Wheat Class Demands

    OpenAIRE

    Wilson, William W.; Gallagher, Paul W.

    1990-01-01

    Price responsiveness and preferences for wheat classes are measured using a Case function specification. Results indicate there have been numerous changes in market shares of wheat classes from different exporters in specific markets. In general, quality differentials are important in some international markets; in others, relative prices are more important in determining market shares.

  6. Race and Class in a Culture of Risk

    Science.gov (United States)

    McDermott, Ray; Raley, Jason D.; Seyer-Ochi, Ingrid

    2009-01-01

    Studies of race, class, and educational risk often proceed in an established but misleading order: First, race is defined as a trait given at birth and turned into trouble by prejudice and unequal conditions; then, class is defined as traits socialized into children with diminished socioeconomic opportunities; finally, risk is treated as the…

  7. The Pearson diffusions: A class of statistically tractable diffusion processes

    DEFF Research Database (Denmark)

    Forman, Julie Lyng; Sørensen, Michael

    The Pearson diffusions is a flexible class of diffusions defined by having linear drift and quadratic squared diffusion coefficient. It is demonstrated that for this class explicit statistical inference is feasible. Explicit optimal martingale estimating func- tions are found, and the corresponding...

  8. Radar Observations of Main-Belt M-class Asteroids

    NARCIS (Netherlands)

    Shepard, Michael K.; Clark, B. E.; Ockert-Bell, M.; Nolan, M. C.; Howell, E. S.; Magri, C.; Giorgini, J. D.; Benner, L. A. M.; Ostro, S. J.; Harris, A. W.; Warner, B. D.; Stephens, R. D.; Mueller, M.

    2009-01-01

    Using the S-band radar at Arecibo Observatory, we have observed 19 Tholen M-class asteroids. The mean radar albedo for all our targets is 0.28 ± 0.13, considerably higher than the mean radar albedo of every other class (Magri et al. 2007, Icarus 186, 126-151). We find approximately one-third (six) o

  9. In the Physics Class: University Physics Students' Enactment of Class and Gender in the Context of Laboratory Work

    Science.gov (United States)

    Danielsson, Anna T.

    2014-01-01

    This article explores how the doing of social class and gender can intersect with the learning of science, through case studies of two male, working-class university students' constitutions of identities as physics students. In doing so, I challenge the taken-for-granted notion that male physics students have an unproblematic relation to…

  10. Questions of Degree? Middle-Class Rejection of Higher Education and Intra-Class Differences in Educational Decision-Making

    Science.gov (United States)

    Morrison, Andrew

    2011-01-01

    This article is an analysis of middle-class rejection of higher education. The author uses accounts of the educational decision-making of three female students, all identified to be from broadly middle-class backgrounds, from within full-time vocational further education in the United Kingdom, as a means to consider two issues. First, the author…

  11. Antimicrobial resistance markers of class 1 and class 2 integron-bearing Escherichia coli from irrigation water and sediments.

    Science.gov (United States)

    Roe, Matthew T; Vega, Everardo; Pillai, Suresh D

    2003-07-01

    Municipal and agricultural pollution affects the Rio Grande, a river that separates the United States from Mexico. Three hundred and twenty-two Escherichia coli isolates were examined for multiple antibiotic resistance phenotypes and the prevalence of class 1 and class 2 integron sequences. Thirty-two (10%) of the isolates were resistant to multiple antibiotics. Four (13%) of these isolates contained class 1-specific integron sequences; one isolate contained class 2 integron-specific sequences. Sequencing showed that the class 1 integron-bearing strain contained two distinct gene cassettes, sat-1 and aadA. Although three of the four class 1 integron-bearing strains harbored the aadA sequence, none of the strains was phenotypically resistant to streptomycin. These results suggest that integron-bearing E. coli strains can be present in contaminated irrigation canals and that these isolates may not express these resistance markers. PMID:12890322

  12. A benefit-risk assessment of class III antiarrhythmic agents

    DEFF Research Database (Denmark)

    Elming, Hanne; Brendorp, Bente; Pehrson, Steen;

    2004-01-01

    relief. Since many patients experience a decrease in physical performance as well as a diminished quality of life during arrhythmia there is still a need for antiarrhythmic drug therapy. The development of new antiarrhythmic agents has changed the focus from class I to class III agents since it became...... evident that with class I drug therapy the prevalence of mortality is considerably higher. This review focuses on the benefits and risks of known and newer class III antiarrhythmic agents. The benefits discussed include the ability to maintain sinus rhythm in persistent atrial fibrillation patients, and...... reducing the need for implantable cardioverter defibrillator shock/antitachycardia therapy, since no class III antiarrhythmic agents have proven survival benefit. The risks discussed mainly focus on pro-arrhythmia as torsade de pointes ventricular tachycardia....

  13. Patchy colloidosomes - an emerging class of structures

    Science.gov (United States)

    Rozynek, Z.; Józefczak, A.

    2016-07-01

    A colloidosome, i.e., a selectively permeable capsule composed of colloidal particles forming a stable homogenous shell, is a tiny container that can be used for storage, transportation, and release of cargo species. There are many routes to preparing colloidosomes; dozens of examples of future applications of such colloidal capsules have been demonstrated. Their functionality can be further extended if the capsules are designed to have heterogeneous shells, i.e., one or more regions (patches) of a shell are composed of material with specific properties that differ from the rest of the shell. Such patchy colloidosomes, supplemented by functionalities similar to that offered by well-studied patchy particles, will surely possess advantageous properties when compared with their homogenous counterparts. For example, owing to specific interactions between patches, they either can self-assemble into complex structures; specifically adhere to a surface; release their cargo species in specific direction; or guided-align,-orient or -propel. Fabrication of patchy colloidal microcapsules has long been theorized by scientists able to design different models, but actual large-scale production remains a challenge. Until now, only a few methods for fabricating patchy colloidosomes have been demonstrated, and these include production by means of microfluidics and mechanical pipetting. The field of science related to fabrication and application of patchy colloidosomes is clearly unexplored, and we envision it blooming in the coming years.

  14. Canister filling materials -- Design requirements and evaluation of candidate materials

    International Nuclear Information System (INIS)

    SKB has been evaluating a copper/steel canister for use in the disposal of spent nuclear reactor fuel. Once the canister is breached by corrosion, it is possible that the void volume inside the canister might fill with water. Water inside the canister would moderate the energy of the neutrons emitted by spontaneous fission in the fuel. It the space in the canister between and around the fuel pins is occupied by canister filling materials, the potential for criticality is avoided. The authors have developed a set of design requirements for canister filling material for the case where it is to be used alone, with no credit for burnup of the fuel or other measures, such as the use of neutron absorbers. Requirements were divided into three classes: essential requirements, desirable features, and undesirable features. The essential requirements are that the material fill at least 60% of the original void space, that the solubility of the filling material be less than 100 mg/l in pure water or expected repository waters at 50 C, and that the material not compact under its own weight by more than 10%. In this paper they review the reasons for these requirements, the desirable and undesirable features, and evaluate 11 candidate materials with respect to the design requirements and features. The candidate materials are glass beads, lead shot, copper spheres, sand, olivine, hematite, magnetite, crushed rock, bentonite, other clays, and concrete. Emphasis is placed on the determination of whether further work is needed to eliminate uncertainties in the evaluation of the ability of a particular filling material to be successfully used under actual conditions, and on the ability to predict the long-term performance of the material under the repository conditions

  15. Machinability of advanced materials

    CERN Document Server

    Davim, J Paulo

    2014-01-01

    Machinability of Advanced Materials addresses the level of difficulty involved in machining a material, or multiple materials, with the appropriate tooling and cutting parameters.  A variety of factors determine a material's machinability, including tool life rate, cutting forces and power consumption, surface integrity, limiting rate of metal removal, and chip shape. These topics, among others, and multiple examples comprise this research resource for engineering students, academics, and practitioners.

  16. Analysis of irradiated materials

    International Nuclear Information System (INIS)

    Papers presented at the UKAEA Conference on Materials Analysis by Physical Techniques (1987) covered a wide range of techniques as applied to the analysis of irradiated materials. These varied from reactor component materials, materials associated with the Authority's radwaste disposal programme, fission products and products associated with the decommissioning of nuclear reactors. An invited paper giving a very comprehensive review of Laser Ablation Microprobe Mass Spectroscopy (LAMMS) was included in the programme. (author)

  17. Class effect of pharmacotherapy in bipolar disorder: fact or misbelief?

    Directory of Open Access Journals (Sweden)

    Vieta Eduard

    2011-03-01

    Full Text Available Abstract Background Anecdotal reports suggests that most clinicians treat medications as belonging to a class with regard to all therapeutic indications; this means that the whole 'class' of drugs is considered to possesses a specific therapeutic action. The present article explores the possible existence of a true 'class effect' for agents available for the treatment of bipolar disorder. Methods We reviewed the available treatment data from randomized controlled trials (RCTs and explored 16 'agent class'/'treatment issue' cases for bipolar disorder. Four classes of agents were examined: first-generation antipsychotics (FGAs, second-generation antipsychotics (SGAs, antiepileptics and antidepressants, with respect to their efficacy on four treatment issues of bipolar disorder (BD (acute mania, acute bipolar depression, maintenance against mania, maintenance against depression. Results From the 16 'agent class'/' treatment issue' cases, only 3 possible class effects were detected, and they all concerned acute mania and antipsychotics. Four effect cases have not been adequately studied (FGAs against acute bipolar depression and in maintenance protection from depression, and antidepressants against acute mania and protection from mania and they all concern treatment cases with a high risk of switching to the opposite pole, thus research in these areas is poor. There is no 'class effect' at all concerning antiepileptics. Conclusions The available data suggest that a 'class effect' is the exception rather than the rule in the treatment of BD. However, the possible presence of a 'class effect' concept discourages clinicians from continued scientific training and reading. Focused educational intervention might be necessary to change this attitude.

  18. Using Storytelling Strategies to Improve Student Comprehension in Online Classes

    Science.gov (United States)

    Powell, Rasby Marlene; Murray, Ottis

    2012-01-01

    Previous research shows that presenting class material in story formats can improve student learning in lecture classes. This pilot study of eight sociology classes investigates the efficacy of using storytelling as a means to improve student comprehension in online classes. Our findings show that when material is presented in story format rather…

  19. The Crucial Aspects of Class: An Empirical Assessment of the Relevance of Class Analysis with Swedish Data Covering the Late Twentieth Century

    OpenAIRE

    Erik Bihagen; Björn Halleröd

    2000-01-01

    Class structure and class formation are two crucial aspects of class. The former relates to differences in market positions and the latter concerns social factors such as interaction, mobility and class action. This paper is based on Swedish data covering the period from 1975 to 1995. Analysis reveals a persistent class hierarchy and that there is no trend towards declining class differences regarding market position. The situation is better described as being in a state of non-linear flux. H...

  20. Gender, class and space in the field of parenthood: comparing middle-class fractions in Amsterdam and London

    OpenAIRE

    Boterman, W.R.; Bridge, G.

    2014-01-01

    This paper argues that becoming a parent/carer can be seen as a new field of social relations and suggests how gender is the key mechanism in the reconfiguration of class relations in this field. By conceptualising parenthood as a field, that is a social world with specific stakes and rules, this study suggests that residential decisions and strategies developed by different middle-class households do not solely depend on their class habitus, but also on gendered positions and dispositions in...

  1. Materials Analysis and Modeling of Underfill Materials.

    Energy Technology Data Exchange (ETDEWEB)

    Wyatt, Nicholas B [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Chambers, Robert S. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-08-01

    The thermal-mechanical properties of three potential underfill candidate materials for PBGA applications are characterized and reported. Two of the materials are a formulations developed at Sandia for underfill applications while the third is a commercial product that utilizes a snap-cure chemistry to drastically reduce cure time. Viscoelastic models were calibrated and fit using the property data collected for one of the Sandia formulated materials. Along with the thermal-mechanical analyses performed, a series of simple bi-material strip tests were conducted to comparatively analyze the relative effects of cure and thermal shrinkage amongst the materials under consideration. Finally, current knowledge gaps as well as questions arising from the present study are identified and a path forward presented.

  2. 41 CFR 301-10.121 - What classes of airline accommodations are available?

    Science.gov (United States)

    2010-07-01

    ...-class. The basic class of accommodation by airlines that is normally the lowest fare offered regardless... airlines as “tourist class,” “economy class,” or as “single class” when the airline offers only one class... as full-fare economy class, and only restricted economy fares are available in the back of...

  3. Terminology of carbonaceous materials

    Energy Technology Data Exchange (ETDEWEB)

    Bagrov, G.N.; Nagornyi, V.G.; Ostrovskii, V.S.

    1986-07-01

    The need is discussed to standardize definition of carbonaceous material. Terms related to carbonaceous materials and their products are selected and analyzed. Diagramatic representation is given of relationships between carbonaceous materials. Carbon has two forms of structure, cubic and hexagonal, characterized by sp/sup 3/-hybrid groups of atoms forming spatial system of tetrahedral bonds. Hexagonal form of carbon is represented by natural materials such as graphite, shungite, anthracite and a number of artificial materials obtained during thermal treatment of organic substances at temperatures above carbonization temperature. 4 references.

  4. 49 CFR 173.2a - Classification of a material having more than one hazard.

    Science.gov (United States)

    2010-10-01

    ... PG I. Note 2: A material which meets the definition of Class 8 and has an inhalation toxicity by... meets the definition of more than one hazard class or division as defined in this part, shall be classed... the definition of a pyrophoric material in § 173.124(b)(1) of this subchapter (Division 4.2). (7)...

  5. Mid-Infrared Observations of Class I/Flat-Spectrum Systems in Six Nearby Molecular Clouds

    Science.gov (United States)

    Haisch, Karl E., Jr.; Barsony, Mary; Ressler, Michael E.; Greene, Thomas P.

    2006-12-01

    We have obtained new mid-infrared observations of 65 Class I/flat-spectrum (FS) objects in the Perseus, Taurus, Chamaeleon I and II, ρ Ophiuchi, and Serpens dark clouds. These objects represent a subset of the young stellar objects (YSOs) from our previous near-infrared multiplicity surveys. We detected 45 out of 48 (94%) of the single sources, 16 out of 16 (100%) of the primary components, and 12 out of 16 (75%) of the secondary/triple components of the binary/multiple objects surveyed. One target, IRS 34, a 0.31" separation FS binary, remains unresolved at near-infrared wavelengths. The composite spectral energy distributions for all of our sample YSOs are either Class I or FS, and in 15 out of 16 multiple systems at least one of the individual components displays a Class I or FS spectral index. However, the occurrence of mixed pairings, such as FS with Class I, FS with Class II, and, in one case, an FS with a Class III (Cha I T33B), is suprisingly frequent. Such behavior is not consistent with that of multiple systems among T Tauri stars (TTSs), where the companion of a classical TTS also tends to be a classical TTS, although other mixed pairings have been previously observed among Class II YSOs. Based on an analysis of the spectral indices of the individual binary components, there appears to be a higher proportion of mixed Class I/FS systems (65%-80%) than that of mixed classical and weak-lined TTSs (25%-40%), demonstrating that the envelopes of Class I/FS systems are rapidly evolving during this evolutionary phase. In general, the individual binary/multiple components suffer very similar extinctions, Av, suggesting that most of the line-of-sight material is either in the foreground of the molecular cloud or circumbinary. We report the discovery of a steep spectral index secondary companion to ISO-Cha I 97, detected for the first time via our mid-infrared observations. In our previous near-infrared imaging survey of binary/multiple Class I and FS YSOs, ISO

  6. Doing Class Analysis in Singapore's Elite Education: Unravelling the Smokescreen of "Meritocratic Talk"

    Science.gov (United States)

    Koh, Aaron

    2014-01-01

    This paper examines the specificity of the education-class nexus in an elite independent school in Singapore. It seeks to unravel the puzzle that meritocracy is dogmatically believed in Singapore in spite of evidences that point to the contrary. The paper draws on discursive (analysis of media materials) and institutional (analysis of interview…

  7. Cyclic subgroups in class groups of real quadratic fields

    International Nuclear Information System (INIS)

    While examining the class numbers of the real quadratic field Q(√n2 + 3n + 9), we observed that the class number is often a multiple of 3. There is a simple explanation for this, namely -27 = (2n + 3)2 - 4(n2 + 3n + 9), so the cubes of the prime ideals above 3 are principal. If the prime ideals themselves are non-principal then 3 must divide the class number. In the present paper, we study this idea from a couple different directions. In the first section we present a criterion that allows us to show that the ideal class group of a real quadratic field has a cyclic subgroup of a given order n. We then give several families of fields to which this criterion applies, hence in which the ideal class groups contain elements of order n. In the second section, we discuss the situation where there is only a potential element of order p (=an odd prime) in the class group, such as the situation described above. We present a modification of the Cohen-Lenstra heuristics for the probability that in this situation the class number is actually a multiple of p. We also extend this idea to predict how often the potential element of order p is actually non-trivial. Both of these predictions agree fairly well with the numerical data. (author). 14 refs, 2 tabs

  8. Meanings of Materials

    NARCIS (Netherlands)

    Karana, E.

    2009-01-01

    This book is about meanings we attribute to materials of the objects around us. Materials convey meanings: they look traditional, they express luxury, they are associated with factories, or they conjure up one’s childhood. How do materials obtain these meanings? How do they interact with other e

  9. Improvising with Material in the Higher Education Dance Technique Class: Exploration and Ownership

    Science.gov (United States)

    Rimmer, Rachel

    2013-01-01

    In this article the author, Rachel Rimmer, explores how improvisation can facilitate skills that are transferable to other areas of dance practice, enabling different areas of study to complement each other. The experimental forum of improvisation as an alternative method of learning technique is considered, contemplating the value of this…

  10. Syntactic classes of subordinate clauses in German

    Directory of Open Access Journals (Sweden)

    Hardarik Blühdorn

    2013-06-01

    Full Text Available O artigo dá uma visão panorâmica das classes de orações subordinadas da língua alemã. Suas funções e estruturas sintáticas são descritas mediante o esquema das posições e dos campos. Três aspectos específicos são tratados mais a fundo: as funções (i de pronomes e (ii de partículas de comparação em relação a orações subordinadas e (iii o papel de orações subordinadas em construções clivadas. O artigo pode ser usado para fins didáticos no meio acadêmico e como ponto de partida para estudos em sintaxe comparativa.

  11. A class of globally convergent conjugate gradient methods

    Institute of Scientific and Technical Information of China (English)

    DAI; Yuhong(戴彧虹); YUAN; Yaxiang(袁亚湘)

    2003-01-01

    Conjugate gradient methods are very important ones for solving nonlinear optimization problems,especially for large scale problems. However, unlike quasi-Newton methods, conjugate gradient methods wereusually analyzed individually. In this paper, we propose a class of conjugate gradient methods, which can beregarded as some kind of convex combination of the Fletcher-Reeves method and the method proposed byDai et al. To analyze this class of methods, we introduce some unified tools that concern a general methodwith the scalarβk having the form of φk/φk-1. Consequently, the class of conjugate gradient methods canuniformly be analyzed.

  12. Two Classes of Crooked Multinomials Inequivalent to Power Functions

    CERN Document Server

    Duan, Xueying

    2011-01-01

    It is known that crooked functions can be used to construct many interesting combinatorial objects, and a quadratic function is crooked if and only if it is almost perfect nonlinear (APN). In this paper, we introduce two infinite classes of quadratic crooked multinomials on fields of order $2^{2m}$. One class of APN functions constructed in [7] is a particular case of the one we construct in Theorem 1. Moreover, we prove that the two classes of crooked functions constructed in this paper are EA inequivalent to power functions and conjecture that CCZ inequivalence between them also holds.

  13. Steinitz class of elliptic curves with complex multilication

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Let E be any elliptic curve having complex multiplication by the ring CK of integers of the quadratic number field K= Q(- D). Let H be the Hilbert class field of K. The Mordell-Weil group E(H) of H-rational points is a module over the Dedekind domain CK, its structure depends on its Steinitz class. Here the Steinits class is determined when D is any prime number. This result advances the result for the specific elliptic curves when D=10.A general theorem on structure of modules over Dedekind domain is also proposed.

  14. 49 CFR 174.700 - Special handling requirements for Class 7 (radioactive) materials.

    Science.gov (United States)

    2010-10-01

    ... by rail car or stored at any single location is limited to a total transport index and a total... between areas) which may be continuously occupied by any passenger, rail employee, or shipment of one or... the transport index numbers on the labels of the individual packages) of packages in the rail car...

  15. Building an Evolving Method and Materials for Teaching Legal Writing in Large Classes

    Science.gov (United States)

    Clarence, Sherran; Albertus, Latiefa; Mwambene, Lea

    2014-01-01

    In South Africa and in other parts of the world, many professions are bemoaning the poor ability of many graduates to communicate their skills and knowledge effectively once they enter the workplace. Increasingly, pressure is placed on higher education to do more in terms of equipping future professionals with the necessary critical reading,…

  16. Dual MHC class I and class II restriction of a single T cell receptor: distinct modes of tolerance induction by two classes of autoantigens.

    Science.gov (United States)

    Arsov, I; Vukmanović, S

    1999-02-15

    In the final stages of thymic development, immature T cells undergo three distinct processes (positive selection, negative selection, and lineage commitment) that all depend on interactions of thymocyte TCRs with MHC molecules. It is currently thought that TCRs are preferentially restricted by either MHC class I or class II molecules. In this report, we present direct evidence that the TCR previously described as H-Y/H-2Db specific cross-reacts with H-2IAb if expressed in CD4+ cells. We also demonstrate an increase in thymocyte numbers in H-Y TCR-trangenic mice deficient in MHC class II, suggesting a relatively discrete form of negative selection by MHC class II compared with that induced by H-Y/H-2Db. We propose that inability to generate CD4+ T cells expressing H-Y TCR in different experimental settings may be due to tolerance to self-MHC class II. These results, therefore, support an intriguing possibility that tolerance to self may influence and/or interfere with the outcome of the lineage commitment. PMID:9973472

  17. Modelling of thermoelectric materials

    DEFF Research Database (Denmark)

    Bjerg, Lasse

    In order to discover new good thermoelectric materials, there are essentially two ways. One way is to go to the laboratory, synthesise a new material, and measure the thermoelectric properties. The amount of compounds, which can be investigated this way is limited because the process is time...... consuming. Another approach is to model the thermoelectric properties of a material on a computer. Several crystal structures can be investigated this way without use of much man power. I have chosen the latter approach. Using density functional theory I am able to calculate the band structure of a material....... This band structure I can then use to calculate the thermoelectric properties of the material. With these results I have investigated several materials and found the optimum theoretical doping concentration. If materials with these doping concentrations be synthesised, considerably better thermoelectric...

  18. Management of Class I and Class II Amalgam Restorations with Localized Defects: Five-Year Results

    Directory of Open Access Journals (Sweden)

    Javier Martin

    2013-01-01

    Full Text Available Replacement of dental restorations has been the traditional treatment for defective restorations. This five-year prospective clinical trial evaluated amalgam restorations with localized defects that were treated by means of repair or refurbishing. Fifty-two patients (50% female and 50% male, mean age 28.3±18.1 years, range 18–80 with 160 class I and class II defective restorations were included. The study focused on the application of two minimally invasive treatments for localized restoration defects and compared these with no treatment and total replacement as negative and positive controls, respectively. Restorations were assessed by two calibrated examiners according to modified U.S. Public Health Service criteria, including marginal adaptation, anatomic form, secondary caries, and roughness. At five years, recall was examined in 45 patients with 108 restorations (67.5%. The results suggest that repair treatment is as effective as total replacement of restorations with localized defects, reducing biological costs to the patient and providing new tools to the clinician. Refinishing restoration is a useful treatment for localized anatomic form defects.

  19. Study of Asymmetric Polling System with Two Message Classes

    Institute of Scientific and Technical Information of China (English)

    CAO Chun-sheng; ZHANG Wei-dong

    2007-01-01

    A novel mixed polling system with multiple stations is considered.Each station produces two classes of messages served with different disciplines.The real time message served with exhaustive service discipline and the unreal time message served with gated service discipline.Using an iterative method, the exact mean waiting times for both message classes are derived.The influence of the gate location of the message class served by the gated service discipline on the mean waiting time is also analyzed.The analytical results are verified with simulation method and agree well with simulation results.

  20. Stringy Chern classes of singular toric varieties and their applications

    CERN Document Server

    Batyrev, Victor

    2016-01-01

    Let X be a normal projective Q-Gorenstein variety with at worst log-terminal singularities. We prove a formula expressing the total stringy Chern class of a generic complete intersection in X via the total stringy Chern class of X. This formula is motivated by its applications to mirror symmetry for Calabi-Yau complete intersections in toric varieties. We compute stringy Chern classes and give a combinatorial interpretation of the stringy Libgober-Wood identity for arbitrary projective Q-Gorenstein toric varieties. As an application we derive a new combinatorial identity relating d-dimensional reflexive polytopes to the number 12 in dimension d>3.

  1. Polynomial approximations of a class of stochastic multiscale elasticity problems

    Science.gov (United States)

    Hoang, Viet Ha; Nguyen, Thanh Chung; Xia, Bingxing

    2016-06-01

    We consider a class of elasticity equations in {mathbb{R}^d} whose elastic moduli depend on n separated microscopic scales. The moduli are random and expressed as a linear expansion of a countable sequence of random variables which are independently and identically uniformly distributed in a compact interval. The multiscale Hellinger-Reissner mixed problem that allows for computing the stress directly and the multiscale mixed problem with a penalty term for nearly incompressible isotropic materials are considered. The stochastic problems are studied via deterministic problems that depend on a countable number of real parameters which represent the probabilistic law of the stochastic equations. We study the multiscale homogenized problems that contain all the macroscopic and microscopic information. The solutions of these multiscale homogenized problems are written as generalized polynomial chaos (gpc) expansions. We approximate these solutions by semidiscrete Galerkin approximating problems that project into the spaces of functions with only a finite number of N gpc modes. Assuming summability properties for the coefficients of the elastic moduli's expansion, we deduce bounds and summability properties for the solutions' gpc expansion coefficients. These bounds imply explicit rates of convergence in terms of N when the gpc modes used for the Galerkin approximation are chosen to correspond to the best N terms in the gpc expansion. For the mixed problem with a penalty term for nearly incompressible materials, we show that the rate of convergence for the best N term approximation is independent of the Lamé constants' ratio when it goes to {infty}. Correctors for the homogenization problem are deduced. From these we establish correctors for the solutions of the parametric multiscale problems in terms of the semidiscrete Galerkin approximations. For two-scale problems, an explicit homogenization error which is uniform with respect to the parameters is deduced. Together

  2. On a class of fourth order linear recurrence equations

    Directory of Open Access Journals (Sweden)

    Sui-Sun Cheng

    1984-03-01

    Full Text Available This paper is concerned with sequences that satisfy a class of fourth order linear recurrence equations. Basic properties of such sequences are derived. In addition, we discuss the oscillatory and nonoscillatory behavior of such sequences.

  3. On a class of graphs with prescribed mean curvature

    International Nuclear Information System (INIS)

    We study a class of quasilinear elliptic equations on the unit ball of Rn and apply these results to get the existence of graphs with prescribed mean curvature on n-hyperbolic spaces. (author). 18 refs

  4. Micromechanics of hierarchical materials

    DEFF Research Database (Denmark)

    Mishnaevsky, Leon, Jr.

    2012-01-01

    A short overview of micromechanical models of hierarchical materials (hybrid composites, biomaterials, fractal materials, etc.) is given. Several examples of the modeling of strength and damage in hierarchical materials are summarized, among them, 3D FE model of hybrid composites with...... nanoengineered matrix, fiber bundle model of UD composites with hierarchically clustered fibers and 3D multilevel model of wood considered as a gradient, cellular material with layered composite cell walls. The main areas of research in micromechanics of hierarchical materials are identified, among them, the...... investigations of the effects of load redistribution between reinforcing elements at different scale levels, of the possibilities to control different material properties and to ensure synergy of strengthening effects at different scale levels and using the nanoreinforcement effects. The main future directions...

  5. Cohort Dropout Study: The Class of 1986. OEA Analytic Report.

    Science.gov (United States)

    New York City Board of Education, Brooklyn. Office of Educational Assessment.

    In order to determine the extent to which New York City students are dropping out of high school, the progress of the over 70,000 members of the class of 1986 was followed from September 1982, through June 1986. By the date of their anticipated graduation, the class of 1986 was characterized by the following: (1) 22 percent had dropped out; (2) 12…

  6. Explaining Social Class Inequalities in Educational Achievement in the UK: Quantifying the Contribution of Social Class Differences in School "Effectiveness"

    Science.gov (United States)

    Hobbs, Graham

    2016-01-01

    There are large social class inequalities in educational achievement in the UK. This paper quantifies the contribution of one mechanism to the production of these inequalities: social class differences in school "effectiveness," where "effectiveness" refers to a school's impact on pupils' educational achievement (relative to…

  7. Reinforcement of ceramic materials

    International Nuclear Information System (INIS)

    In the commercial field, greater reproduceability of ceramic materials was achieved by systematic process control of the steps in manufacture. By improvement of the microstructure design, the strength and toughness against tearing of the materials were increased. The articles give a survey of theoretical and experimental results in manufacture and of the composition of ceramics with reinforced structure. Preferred materials are zirconium-, aluminium- and yttrium oxide, silicon oxide and -nitride and titanium- and silicon carbide. (DG)

  8. Piezoelectric actuators control applications of smart materials

    CERN Document Server

    Choi, Seung-Bok

    2010-01-01

    Newer classes of smart materials are beginning to display the capacity for self-repair, self-diagnosis, self-multiplication, and self-degradation. While there are other candidates, piezoelectric actuators and sensors are proving to be the best choice. This title details the authors' research and development in this area.

  9. ON CLASSES OF REGULAR GRAPHS WITH CONSTANT METRIC DIMENSION

    Institute of Scientific and Technical Information of China (English)

    Muhammad IMRAN; Syed Ahtsham ul Haq BOKHARY; Ali AHMAD; Andrea SEMANI(C)OV(A)-FE(N)OV(C)(I)KOV(A)

    2013-01-01

    In this paper,we are dealing with the study of the metric dimension of some classes of regular graphs by considering a class of bridgeless cubic graphs called the flower snarks Jn,a class of cubic convex polytopes considering the open problem raised in [M.Imran et al.,families of plane graphs with constant metric dimension,Utilitas Math.,in press] and finally Harary graphs H5,n by partially answering to an open problem proposed in [I.Javaid et al.,Families of regular graphs with constant metric dimension,Utilitas Math.,2012,88:43-57].We prove that these classes of regular graphs have constant metric dimension.

  10. Class preserving automorphisms of finite $p$-groups: A survey

    OpenAIRE

    Yadav, Manoj K.

    2010-01-01

    In this short survey article, we try to list maximum number of known results on class preserving automorphisms of finite $p$-groups. We conclude the survey with some interesting (at least for the author) open problems on this topic.

  11. Class preserving automorphisms of finite $p$-groups: A survey

    CERN Document Server

    Yadav, Manoj K

    2010-01-01

    In this short survey article, we try to list maximum number of known results on class preserving automorphisms of finite $p$-groups. We conclude the survey with some interesting (at least to me) open problems on this topic.

  12. Software Sensors Design for a Class of Aerobic Fermentation Processes

    OpenAIRE

    Trayana Patarinska; Vasil Trenev; Silvia Popova

    2010-01-01

    The problem of on-line state and parameter estimation (software sensors design) of a class of aerobic fermentation processes for metabolite product formation is considered. The class is characterized by: two limiting substrates one of which, growth factor, is practically depleted during the biomass growth where the product formation is negligible; corresponding general reaction scheme – a qualitative description of the main metabolic reactions between the main components in the liquid phase (...

  13. Controlling class size to manage enrollment decline of secondary schools

    OpenAIRE

    Ma, Jo-zin.; 馬晉修.

    2012-01-01

    In the recent decade or so, the phenomenon of enrollment decline of secondary schools has been clearly observed in Hong Kong. The significance of this phenomenon has grown over time such that the number of public sector schools has had to be reduced. Meanwhile, an alternative to school closure is to reduce the class size of schools which is however not less controversial. On the surface, the arguments against class size reduction include perceived extra cost per student and ineffectiveness o...

  14. Who is More Responsible? Preparatory Class Students’ Perceptions of Responsibility

    OpenAIRE

    CESUR, Kürşat; Ertaş, Abdullah

    2014-01-01

     The main aim of this study is to explore learners’ perceptions of their own responsibility in learning English. The question of whether our learners in Canakkale Onsekiz Mart University (hereafter COMU) Compulsory and Voluntary English Language Prep Classes are responsible enough for their own learning or not is the main focus of this study. Whether some variables like gender, the type of the prep class education (compulsory or voluntary) and the students’ departments will affect their perce...

  15. Coincidence Theorems for Certain Classes of Hybrid Contractions

    Directory of Open Access Journals (Sweden)

    Singh SL

    2010-01-01

    Full Text Available Coincidence and fixed point theorems for a new class of hybrid contractions consisting of a pair of single-valued and multivalued maps on an arbitrary nonempty set with values in a metric space are proved. In addition, the existence of a common solution for certain class of functional equations arising in dynamic programming, under much weaker conditions are discussed. The results obtained here in generalize many well known results.

  16. Classes of secondary metabolites identified in three legume species

    OpenAIRE

    Delci de Deus Nepomuceno; João Carlos de Carvalho Almeida; Mário Geraldo de Carvalho; Renata Duarte Fernandes; Francisco Eduardo Aragão Catunda Júnior

    2013-01-01

    The objective of this study was to identify secondary metabolite classes of tropical kudzu, perennial soybean and archer legumes through identification by phytochemical screening and confirmation by infrared (IR), ¹H and carbon-13 NMR spectroscopy of fractions obtained by organic solvents partition of crude extracts. These analyses allowed for proposing the presence of the following metabolite classes: reducing sugars, saccharides, saponins, cardiac glucosides, terpenes, coumarins, tannins, a...

  17. Classes of Spatiotemporal Objects and Their Closure Properties

    OpenAIRE

    Chomicki, Jan; Haesevoets, Sofie; Kuijpers, Bart; Revesz, Peter

    2002-01-01

    We present a data model for spatio-temporal databases. In this model spatio-temporal data is represented as a finite union of objects described by means of a spatial reference object, a temporal object and a geometric transformation function that determines the change or movement of the reference object in time. We define a number of practically relevant classes of spatio-temporal objects, and give complete results concerning closure under Boolean set operators for these classes. Since only f...

  18. Specificity of Schoolchildren's Social Skills during Physical Education Classes

    OpenAIRE

    Malinauskas, Romualdas; Emeljanovas, Arunas

    2013-01-01

    The objective of the study was to analyse the level of schoolchildren's social skills during physical education classes, and to examine specificity of social skills among schoolchildren during physical education classes. The analysis included 364 schoolchildren (178 male and 186 female students). The data were collected according to social skills inventory prepared by Bakutyte and adapted by Sniras and Malinauskas. An original conception of the exploration of schoolchildren’s social skills du...

  19. Steganography: a class of secure and robust algorithms

    CERN Document Server

    Bahi, Jacques M; Guyeux, Christophe

    2011-01-01

    This research work presents a new class of non-blind information hiding algorithms that are stego-secure and robust. They are based on some finite domains iterations having the Devaney's topological chaos property. Thanks to a complete formalization of the approach we prove security against watermark-only attacks of a large class of steganographic algorithms. Finally a complete study of robustness is given in frequency DWT and DCT domains.

  20. Exploring the Potential of Smartphones and Tablets for Performance Support in Food Chemistry Laboratory Classes

    Science.gov (United States)

    van der Kolk, Koos; Hartog, Rob; Beldman, Gerrit; Gruppen, Harry

    2013-01-01

    Increasingly, mobile applications appear on the market that can support students in chemistry laboratory classes. In a multiple app-supported laboratory, each of these applications covers one use-case. In practice, this leads to situations in which information is scattered over different screens and written materials. Such a multiple app-supported…

  1. Dosing method of physical activity in aerobics classes for students

    Directory of Open Access Journals (Sweden)

    Beliak Yu.I.

    2014-10-01

    Full Text Available Purpose : reasons for the method of dosing of physical activity in aerobics classes for students. The basis of the method is the evaluation of the metabolic cost of funds used in them. Material : experiment involved the assessment of the pulse response of students to load complexes classical and step aerobics (n = 47, age 20-23 years. In complexes used various factors regulating the intensity: perform combinations of basic steps, involvement of movements with his hands, holding in hands dumbbells weighing 1kg increase in the rate of musical accompaniment, varying heights step platform. Results . on the basis of the relationship between heart rate and oxygen consumption was determined by the energy cost of each admission control load intensity. This indicator has been used to justify the intensity and duration of multiplicity aerobics. Figure correspond to the level of physical condition and motor activity deficits students. Conclusions : the estimated component of this method of dosing load makes it convenient for use in automated computer programs. Also it can be easily modified to dispense load other types of recreational fitness.

  2. Safety learning from drugs of the same class

    DEFF Research Database (Denmark)

    Stefansdottir, G; Knol, M J; Arnardottir, A H;

    2012-01-01

    This study was aimed at assessing the extent of safety learning from data pertaining to other drugs of the same class. We studied drug classes for which the first and second drugs were centrally registered in the European Union from 1995 to 2008. We assessed whether adverse drug reactions (ADRs...... present in both SPCs of a drug pair, 241 (61.3%) were present when the drug entered the market and 152 (30.7%) appeared in the postmarketing phase. The mention of ADRs in the SPCs of both same-class drugs in the postmarketing phase was associated with type A ADRs, marketing in the same regulator country......, a longer time interval between entry into the market by the two drugs, and an earlier date of ADR. Although there appears to be some degree of safety learning from same-class drugs, there is still room for improvement, possibly by increasing proactive risk management....

  3. Computational consideration for selection of social classes in Romania

    Directory of Open Access Journals (Sweden)

    Andoria Ioniţă

    2015-09-01

    Full Text Available Middle class is a subject discussed by almost everyone, judging it in most cases from the visible living standard’s point of view: having the ownership of the dwelling, a car, making trips inside country or abroad, buying good quality and expensive goods or services and so on. But, at least in the case of our country, very often there is not a quantitative measurement of middle class, due to the fact that defining correct and reliable criteria to separate this social class from the others isn’t an easy task. Which are the “latent” factors which ensure each person’s capability to belong to the middle class? How much this affiliation depends on the individual characteristics and how much it depends on external factors like the characteristics of the society in which the persons are living in? A subtle definition of the middle class has to take into consideration several aspects, some of them more easily or more difficult to measure from the quantitative point of view. We are taking about some quantitative criteria like incomes or the number of endowment goods owned by a person, which are criteria relatively easy to estimate thought statistical methods, but also about aspects like wellbeing or social prestige, variables with a strong subjective specificity, on which there is very difficult to find an accord regarding methods of measurement between different specialists. This paper presents the results of an attempt to define social classes for Romania, in order to highlight the dimensions and the social importance of the middle class in our country. The elaboration of the methodology to build the social classes starts from the definition of 11 professional categories, based on the Classification of Occupation in Romania. By using the professional categories defined, which can be considered a first instrument (or a first step for the separation of middle class from the other ones, the present paper presents a first image of the middle

  4. Stability and optimal control for some classes of tritrophic systems.

    Science.gov (United States)

    Galbusera, Luca; Pasquali, Sara; Gilioli, Gianni

    2014-04-01

    The objective of this paper is to study an optimal resource management problem for some classes of tritrophic systems composed by autotrophic resources (plants), bottom level consumers (herbivores) and top level consumers (humans). The first class of systems we discuss are linear chains, in which biomass flows from plants to herbivores, and from herbivores to humans. In the second class of systems humans are omnivorous and hence compete with herbivores for plant resources. Finally, in the third class of systems humans are omnivorous, but the plant resources are partitioned so that humans and herbivores do not complete for the same ones. The three trophic chains are expressed as Lotka-Volterra models, which seems to be a suitable choice in contexts where there is a shortage of food for the consumers. Our model parameters are taken from the literature on agro-pastoral systems in Sub-Saharan Africa. PMID:24245717

  5. Global asymptotic stability for a class of nonlinear chemical equations

    OpenAIRE

    Anderson, David F.

    2007-01-01

    We consider a class of nonlinear differential equations that arises in the study of chemical reaction systems that are known to be locally asymptotically stable and prove that they are in fact globally asymptotically stable. More specifically, we will consider chemical reaction systems that are weakly reversible, have a deficiency of zero, and are equipped with mass action kinetics. We show that if for each $c \\in \\R_{> 0}^m$ the intersection of the stoichiometric compatibility class $c + S$ ...

  6. Molten Air -- A new, highest energy class of rechargeable batteries

    CERN Document Server

    Licht, Stuart

    2013-01-01

    This study introduces the principles of a new class of batteries, rechargeable molten air batteries, and several battery chemistry examples are demonstrated. The new battery class uses a molten electrolyte, are quasi reversible, and have amongst the highest intrinsic battery electric energy storage capacities. Three examples of the new batteries are demonstrated. These are the iron, carbon and VB2 molten air batteries with respective intrinsic volumetric energy capacities of 10,000, 19,000 and 27,000 Wh per liter.

  7. The roles of the teacher in ELT classes

    Institute of Scientific and Technical Information of China (English)

    刘振梅

    2007-01-01

    Nowadays,ELT pays more attention to the ability of communication.So the role of the teacher is very different from the one before.This paper mainly gives an analysis of the possible roles a teacher is supposed to take in an ELT class by dividing the class into three stages,presenting the practical approaches and procedures of teaching to develop students'communicative abilities.

  8. Molten Air -- A new, highest energy class of rechargeable batteries

    OpenAIRE

    Licht, Stuart

    2013-01-01

    This study introduces the principles of a new class of batteries, rechargeable molten air batteries, and several battery chemistry examples are demonstrated. The new battery class uses a molten electrolyte, are quasi reversible, and have amongst the highest intrinsic battery electric energy storage capacities. Three examples of the new batteries are demonstrated. These are the iron, carbon and VB2 molten air batteries with respective intrinsic volumetric energy capacities of 10,000, 19,000 an...

  9. Dynamic Principal Components: a New Class of Multivariate GARCH Models

    OpenAIRE

    Gian Piero Aielli; Massimiliano Caporin

    2015-01-01

    The OGARCH specification is the leading model for a class of multivariate GARCH (MGARCH)specifications that are based on linear combinations of univariate GARCH specifications. Most MGARCH models in this class adopt a spectral decomposition of the covariance matrix, allowing for heteroskedasticity on at least some of the principal components, while the loading matrix, which maps the conditional principal components to the asset returns, is constant over time. This paper extends the OGARCH mod...

  10. Type Iax Supernovae: A New Class of Stellar Explosion

    OpenAIRE

    Foley, Ryan J.; Challis, P. J.; Chornock, R.; Ganeshalingam, M.; Li, W; Marion, G. H.; Morrell, N. I.; Pignata, G.; Stritzinger, M. D.; Silverman, J. M.; X Wang; Anderson, J.P.; Filippenko, A. V.; Freedman, W. L.; Hamuy, M.

    2012-01-01

    We describe observed properties of the Type Iax class of supernovae (SNe Iax), consisting of SNe observationally similar to its prototypical member, SN 2002cx. The class currently has 25 members, and we present optical photometry and/or optical spectroscopy for most of them. SNe Iax are spectroscopically similar to SNe Ia, but have lower maximum-light velocities (2000 M_V,peak > -18.9 mag), and most have hot photospheres. Relative t...

  11. Middle-Class Entrepreneurship and the Effect of Social Capital

    OpenAIRE

    Ordenana, Xavier; Arteaga, Elizabeth

    2012-01-01

    This paper surveys Ecuadorian entrepreneurs to ascertain the differences between middle-class and upper-class entrepreneurs and identify the variables associated with the “success” of a business. The paper also explores the variables that can determine the probability of upward intergenerational mobility. The paper finds that, although the level of social capital among Ecuadorian entrepreneurs is weak, it positively affects the chances of being a dynamic entrepreneur.

  12. Ideal Class Groups and Subgroups of Real Quadratic Function Fields

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    In this paper, we study the real quadratic function fields K=k(D), given a necessary and sufficient condition for the ideal class group H(K) of any real quadratic function field K to have a cyclic subgroup of order n, and obtained eight series of such fields. The ideal class numbers h(OK) of K in the series all have a factor n.

  13. Joining of advanced materials

    CERN Document Server

    Messler, Robert W

    1993-01-01

    Provides an unusually complete and readable compilation of the primary and secondary options for joining conventional materials in non-conventional ways. Provides unique coverage of adhesive bonding using both organic and inorganic adhesives, cements and mortars. Focuses on materials issues without ignoring issues related to joint design, production processing, quality assurance, process economics, and joining performance in service.Joining of advanced materials is a unique treatment of joining of both conventional and advanced metals andalloys, intermetallics, ceramics, glasses, polymers, a

  14. Physical characteristics of bright Class I methanol masers

    Science.gov (United States)

    Leurini, S.; Menten, K. M.; Walmsley, C. M.

    2016-07-01

    Context. Class I methanol masers are thought to be tracers of interstellar shock waves. However, they have received relatively little attention mostly as a consequence of their low luminosities compared to other maser transitions. This situation has changed recently and Class I methanol masers are now routinely used as signposts of outflow activity especially in high extinction regions. The recent detection of polarisation in Class I lines now makes it possible to obtain direct observational information about magnetic fields in interstellar shocks. Aims: We make use of newly calculated collisional rate coefficients for methanol to investigate the excitation of Class I methanol masers and to reconcile the observed Class I methanol maser properties with model results. Methods: We performed large velocity gradient calculations with a plane-parallel slab geometry appropriate for shocks to compute the pump and loss rates which regulate the interactions of the different maser systems with the maser reservoir. We study the dependence of the pump rate coefficient, the maser loss rate, and the inversion efficiency of the pumping scheme of several Class I masers on the physics of the emitting gas. Results: We predict inversion in all transitions where maser emission is observed. Bright Class I methanol masers are mainly high-temperature (>100 K) high-density (n(H2) ~ 107-108 cm-3) structures with methanol maser emission measures, ξ, corresponding to high methanol abundances close to the limits set by collisional quenching. Our model predictions reproduce reasonably well most of the observed properties of Class I methanol masers. Class I masers in the 25 GHz series are the most sensitive to the density of the medium and mase at higher densities than other lines. Moreover, even at high density and high methanol abundances, their luminosity is predicted to be lower than that of the 44 GHz and 36 GHz masers. Our model predictions also reflect the observational result that the

  15. Turkish Managers as a Part of the Transnational Capitalist Class

    Directory of Open Access Journals (Sweden)

    Meltem Yinaz Sener

    2015-08-01

    Full Text Available During the period after 1970s, capitalism has gone through a significant restructuring. This period has been primarily characterized by the process of globalization. Globalization has not emerged as the natural result of capitalism but it has been actively promoted and the appropriate conditions for the functioning of global capitalism have been created by certain actors. Many scholars argue that it is a newly emerging transnational capitalist class which transformed capitalism into a globalizing project. Although the members of this class are located in different parts of the world, they have a common interest in supporting globalization. They are aware of their common interests and they have a certain class consciousness. Moreover, their habits, tastes, and lifestyles are becoming increasingly similar. Considering these debates on transnational capitalist class, in a case study of the Turkish top managers working in the ?stanbul branch of a multinational corporation, this paper looks at the lifestyle characteristics of this group of managers, comparing them with those aspects of the lifestyle of the transnational capitalist class that are indicated by the scholars. A second question that has been considered is to what extent these managers feel themselves as part of a transnational class that has common goals and interests. This study shows that for this group of managers the primary identification is with the people who have the same position with them, regardless of their country or corporation, not with their fellow nationals.

  16. A Further Examination of the Big-Fish-Little-Pond Effect: Perceived Position in Class, Class Size, and Gender Comparisons

    Science.gov (United States)

    Thijs, Jochem; Verkuyten, Maykel; Helmond, Petra

    2010-01-01

    Among early adolescents (10-12 years) in the Netherlands, this study examined the academic self-concept in terms of the big-fish-little-pond effect (BFLPE). The BFLPE implies that students in classes where the average achievement is low will have a higher academic self-concept than equally achieving students in classes where the average…

  17. Effect of age and diameter class on the properties of wood from clonal Eucalyptus

    Directory of Open Access Journals (Sweden)

    Wilma Michele Santos Santana

    2012-03-01

    Full Text Available The objective of this work was to evaluate the influence of age and diameter class on the physical, thermal and chemical characteristics of a clone of Eucalyptus grandis and Eucalyptus urophylla. The material originated from a reforestation site owned by GERDAU S.A. and included trees at age 34, 48, 61, 74 and 86 months. Two trees were selected per age in each diameter class, observing the proportion of each established plot. Analyses of physical characteristics included wood basic density, dry matter weight and carbon stock, and of chemical characteristics included holocellulose, total extractives content, total lignin and ash content, in addition to elemental and thermal analysis of the wood. Results led to the conclusion that most wood properties were influenced by age and diameter class. The species was found to have great potential for production of biomass and generation of heat energy, potentially convertible into mechanical energy and electricity.

  18. 78 FR 21044 - Amendment of Class D and Class E Airspace; Reading, PA

    Science.gov (United States)

    2013-04-09

    ... amend Class D and Class E airspace at Reading, PA (78 FR 5754) Docket No. FAA-2012-1270. Interested... rule'' under DOT Regulatory Policies and Procedures (44 FR 11034; February 26, 1979); and (3) does not..., 40120; E.O. 10854, 24 FR 9565, 3 CFR, 1959-1963 Comp., p. 389. Sec. 71.1 0 2. The incorporation...

  19. Comparison of Group Cohesion, Class Participation, and Exam Performance in Live and Online Classes

    Science.gov (United States)

    Galyon, Charles E.; Heaton, Eleanore C. T.; Best, Tiffany L.; Williams, Robert L.

    2016-01-01

    Though class participation and group cohesion have shown some potential to promote student performance in conventional classrooms, their efficacy has not yet been demonstrated in an online-class setting. Group cohesion, defined as member attraction to and self-identification with a group, is thought to promote positive interdependence and the…

  20. Reassessing Pre-market Regulation of Class III Medical Devices

    OpenAIRE

    Zollinger, Geri

    2003-01-01

    Regulation of medical devices has evolved over the past twenty-five years. Initially, Congress created a regime where the safety and efficacy of all medical devices would be reviewed to varying degrees, depending on the risk posed by the device. Class III devices, the most dangerous class of devices, were to each have a safety and efficacy review. To permit new market entrants on similar grounds as those marketing devices prior to the 1976 Amendments, Congress also created a premarket notific...

  1. Anxiety of primary school students in the biology class

    OpenAIRE

    Stražar, Klavdija

    2014-01-01

    The thesis deals with anxiety among primary school students in biology class. Examination and evaluation process as well as public exposure of students often provokes a slightly increased anxiety which negatively impacts the learning process. The present research studied the level of anxiety in students during the assessment of knowledge and other achievements in biology class in elementary school. The empirical analysis took place in April 2014 at an elementary school in Ljubljana and involv...

  2. Liquid class predictor for liquid handling of complex mixtures

    Science.gov (United States)

    Seglke, Brent W.; Lekin, Timothy P.

    2008-12-09

    A method of establishing liquid classes of complex mixtures for liquid handling equipment. The mixtures are composed of components and the equipment has equipment parameters. The first step comprises preparing a response curve for the components. The next step comprises using the response curve to prepare a response indicator for the mixtures. The next step comprises deriving a model that relates the components and the mixtures to establish the liquid classes.

  3. Fractal position spectrum for a class of oscillators

    International Nuclear Information System (INIS)

    We show that the position operator in a class of f-deformed oscillators has a fractal spectrum, homeomorphic to the Cantor set, via a unitary transformation to Harper’s model. The class corresponds to a choice of ergodic operators for the deformation function. Hofstadter’s butterfly is plotted by direct diagonalization of a position operator with an originally vanishing diagonal. This is equivalent to a one-dimensional hamiltonian without potential. (paper)

  4. Several ways of encouraging students in English class

    Institute of Scientific and Technical Information of China (English)

    赵晓云

    2006-01-01

    Encouragement is not only important in communication but also in teaching. This paper will analyse the importance of encouragement in middle school English class, offering some suggestions on how to improve English classroom teaching.

  5. ASYMPTOTIC SOLUTION TO MODEL FOR A CLASS OF VIRUS TRANSMISSION

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    In this paper, a class of HIV virus transmission is considered. The transmissive dynamic model for the HIV virus is described. Using the functional-variational iteration theory, the rule for human group in the epidemic transmissive area is studied.

  6. AN EFFICIENT CLASSIFICATION OF GENOMES BASED ON CLASSES AND SUBCLASSES

    Directory of Open Access Journals (Sweden)

    B.V. DHANDRA,

    2010-08-01

    Full Text Available The grass family has been the subject of intense research over the past. Reliable and fast classification / sub-classification of large sequences which are rapidly gaining importance due to genome sequencing projects all over the world is contributing large amount of genome sequences to public gene bank . Hence sequence classification has gained importance for predicting the genome function, structure, evolutionary relationships and also gives the insight into the features associated with the biological role of the class. Thus, classification of functional genome is an important andchallenging task to both computer scientists and biologists. The presence of motifs in grass genome chains predicts the functional behavior of the grass genome. The correlation between grass genome properties and their motifs is not always obvious since more than one motif may exist within a genome chain. Due to the complexity of this association most of the data mining algorithms are either non efficient or time consuming. Hence, in this paper we proposed an efficient method for main classes based on classes to reduce the time complexity for the classification of large sequences of grass genomes dataset. The proposed approaches classify the given dataset into classes with conserved threshold and again reclassify the class relaxed threshold into major classes. Experimental results indicate that the proposed method reduces the time complexity keepingclassification accuracy level as that compared with general NNCalgorithm.

  7. Identification of class B and class C floral organ identity genes from rice plants.

    Science.gov (United States)

    Kang, H G; Jeon, J S; Lee, S; An, G

    1998-12-01

    The functions of two rice MADS-box genes were studied by the loss-of-function approach. The first gene, OsMADS4, shows a significant homology to members in the PISTILLATA (PI) family, which is required to specify petal and stamen identity. The second gene, OsMADS3, is highly homologous to the members in the AGAMOUS (AG) family that is essential for the normal development of the internal two whorls, the stamen and carpel, of the flower. These two rice MADS box cDNA clones were connected to the maize ubiquitin promoter in an antisense orientation and the fusion molecules were introduced to rice plants by the Agrobacterium-mediated transformation method. Transgenic plants expressing antisense OsMADS4 displayed alterations of the second and third whorls. The second-whorl lodicules, which are equivalent to the petals of dicot plants in grasses, were altered into palea/lemma-like organs, and the third whorl stamens were changed to carpel-like organs. Loss-of-function analysis of OsMADS3 showed alterations in the third and fourth whorls. In the third whorl, the filaments of the transgenic plants were changed into thick and fleshy bodies, similar to lodicules. Rather than making a carpel, the fourth whorl produced several abnormal flowers. These phenotypes are similar to those of the agamous and plena mutants in Arabidopsis and Antirrhinum, respectively. These results suggest that OsMADS4 belongs to the class B gene family and OsMADS3 belongs to the class C gene family of floral organ identity determination. PMID:9869408

  8. Prediction of MHC class I binding peptides, using SVMHC

    Directory of Open Access Journals (Sweden)

    Elofsson Arne

    2002-09-01

    Full Text Available Abstract Background T-cells are key players in regulating a specific immune response. Activation of cytotoxic T-cells requires recognition of specific peptides bound to Major Histocompatibility Complex (MHC class I molecules. MHC-peptide complexes are potential tools for diagnosis and treatment of pathogens and cancer, as well as for the development of peptide vaccines. Only one in 100 to 200 potential binders actually binds to a certain MHC molecule, therefore a good prediction method for MHC class I binding peptides can reduce the number of candidate binders that need to be synthesized and tested. Results Here, we present a novel approach, SVMHC, based on support vector machines to predict the binding of peptides to MHC class I molecules. This method seems to perform slightly better than two profile based methods, SYFPEITHI and HLA_BIND. The implementation of SVMHC is quite simple and does not involve any manual steps, therefore as more data become available it is trivial to provide prediction for more MHC types. SVMHC currently contains prediction for 26 MHC class I types from the MHCPEP database or alternatively 6 MHC class I types from the higher quality SYFPEITHI database. The prediction models for these MHC types are implemented in a public web service available at http://www.sbc.su.se/svmhc/. Conclusions Prediction of MHC class I binding peptides using Support Vector Machines, shows high performance and is easy to apply to a large number of MHC class I types. As more peptide data are put into MHC databases, SVMHC can easily be updated to give prediction for additional MHC class I types. We suggest that the number of binding peptides needed for SVM training is at least 20 sequences.

  9. Isomorphism classes and automorphism groups of algebras of Weyl type

    Institute of Scientific and Technical Information of China (English)

    SU; Yucai(苏育才); ZHAO; Kaiming(赵开明)

    2002-01-01

    In one of our recent papers, the associative and the Lie algebras of Weyl type A[D] = A F[D] were defined and studied, where A is a commutative associative algebra with an identity element over a field F of any characteristic, and F[D] is the polynomial algebra of a commutative derivation subalgebra D of A. In the present paper, a class of the above associative and Lie algebras A[D] with F being a field of characteristic 0, D consisting of locally finite but not locally nilpotent derivations of A, are studied. The isomorphism classes and automorphism groups of these associative and Lie algebras are determined.

  10. Physical characteristics of bright Class I methanol masers

    CERN Document Server

    Leurini, S; Walmsley, C M

    2016-01-01

    Class I CH$_3$OH masers trace interstellar shocks. They have received little attention mostly as a consequence of their low luminosities; this situation has changed recently and Class I masers are now routinely used as signposts of outflows. The recent detection of polarisation in Class I lines now makes it possible to obtain information on magnetic fields in shocks. We make use of newly calculated collisional rates to investigate the excitation of Class I masers and to reconcile their observed properties with model results. We performed LVG calculations with a plane-parallel slab geometry to compute the pump and loss rates which regulate the interactions of the different maser systems with the maser reservoir. We study the dependence of the pump rate, the loss rate, and the inversion efficiency of the pumping scheme of Class I masers on the physics of the gas. Bright Class I masers are mainly high-temperature high-density structures with maser emission measures corresponding to high CH$_3$OH abundances close...

  11. Modelling of Closed Loop Class E Inverter Based Induction Heater

    Directory of Open Access Journals (Sweden)

    S. Arumugam

    2011-01-01

    Full Text Available This study presents simulation of class E inverter based induction heater system using simulink. DC is converted into high frequency AC using class E inverter. This high frequency AC is used for induction heating. Closed loop systems are modeled and they are simulated using Mat lab Simulink.The results of closed loop systems are presented. The proposed amplifier with two series-parallel resonant load networks will allow sinusoidal output voltage to be achieved by associating with the positive and negative quasi-sinusoidal waveforms. The complementarily activated configuration will provide continuous high-ripple-frequency inputcurrent waveforms; this approach significantly reduces electromagnetic interference and requires very little filtering. With the symmetry of the push-pull Class-E Circuit, there is the additional benefit that the even harmonics are suppressed at the load, and thus there are fewer harmonic distortions.

  12. Research into the environment of science laboratory classes in australian schools

    Science.gov (United States)

    McRobbie, Campbell J.; Giddings, Geoffrey J.; Fraser, Barry J.

    1990-01-01

    Existing instruments for assessing student or teacher perceptions of characteristics of actual or preferred classroom psychosocial environment are unsuitable for one of the most important settings in science teaching, namely, the science laboratory class. Consequently, the Science Laboratory Environment Inventory (SLEI), was designed to assess student or teacher perceptions of seven scales: Teacher Supportiveness, Student Cohesiveness, Open-Endedness, Integration, Organization, Rule Clarity and Material Environment. An important feature of the design of the study was that the new instrument was field tested simultaneously in six countries: Australia, USA, Canada, England, Nigeria and Israel. This paper is based on a sample of 4643 students in 225 individual laboratory classes, together with the teachers of most of these classes. Preliminary analyses were used to shed light on various important research questions including the differences between Actual and Preferred environments, gender differences in perceptions of Actual and Preferred environment, the relationship between the science laboratory environment and attitude towards science laboratory work, differences between school and university laboratory classes, differences between teachers’ and students’ perceptions of the same laboratory classes, and differences between laboratory classes in different science subjects (Physics, Chemistry, Biology).

  13. The rise of China's middle class and prospects for democratization

    OpenAIRE

    Cichon, Frederick A.

    2007-01-01

    Since Deng Xiaoping instituted economic reforms under the "reform and open" policy in 1978, the Chinese Communist Party has overseen a gradualist approach to modernizing China's economy. A new Chinese middle class has emerged with China's economic reforms and economic growth. According to Seymour Martin Lipset's modernization theory, there is a strong relationship between socioeconomic development and the emergence of democratic politics accompanying the growth of an educated middle class...

  14. Class II barodontalgia: review and report of a case.

    Science.gov (United States)

    Woodmansey, Karl

    2008-01-01

    Barodontalgia is a rarely reported condition involving changes in ambient pressure resulting in tooth pain. According to Ferjentsik and Aker, Class II barodontalgia is observed in teeth that have pre-existing pulpal disease and an ultimate diagnosis of irreversible pulpitis.1 This article describes a case of Class II barodontalgia that was experienced on a commercial airline flight and reviews current knowledge regarding this phenomenon, including proposed etiologic mechanisms. PMID:21444271

  15. Assessment of toxicity and hazard class slag of incinerator

    Directory of Open Access Journals (Sweden)

    Demura V.I.

    2016-02-01

    Full Text Available Researches of the contents soluble forms of heavy metals in waste are executed. The estimation of a degree of toxicity of products of thermal processing of waste is lead. It is established, that slag of an incinerate factory concerns to І class of danger under the contents of mobile forms of heavy meta

  16. The roles of social class of origin, achieved social class and intergenerational social mobility in explaining social-class inequalities in alcoholism among young men

    DEFF Research Database (Denmark)

    Hemmingsson, T; Lundberg, I; Diderichsen, Finn

    1999-01-01

    The aim of this study was to investigate the role of intergenerational health-related mobility in explaining social-class inequalities in alcoholism among young men. Data on social class of origin and on risk factors in childhood and adolescence, e.g. risk use of alcohol, were collected for 49...... diagnosis. The increased relative risk could, to a considerable extent, be attributed to factors from childhood/adolescence. In this longitudinal study, it is shown that intergenerational social mobility associated with health-related factors, albeit not with illness itself, made a major contribution to...

  17. Analysis of Asset Classes Through the Business Cycle

    Directory of Open Access Journals (Sweden)

    Audrius Dzikevičius

    2012-06-01

    Full Text Available This study was driven by the dissimilar performance characteristics displayed by asset classes over the business cycle. The authors aim to explore assets classes on the grounds of a scientific literature review and a statistical analysis. Business cycles are divided into four stages to explore broad movements in returns of asset classes and a possible existence of asymmetrical effects of determinants within stages. Six main asset classes were analysed: US stocks, EAFE stocks, Bonds, Gold, Real Estate and Commodities. Monthly data from February 1976 to August 2011 were used for the study. The article combines business cycle and asset allocation theories by adding valuable information about performance of asset classes during different phases of the business cycle. Using the OECD Composite Leading Indicator as a business cycle measure, the authors demonstrate that different assets classes have different return/risk characteristics over the business cycle. The article demonstrates how to use the business cycle approach for investment decision-making. The OECD Composite Leading Indicator can provide significant information on market expectations and the future outlook; hence, results of this study can help every investor improve his/her performance and risk management.

  18. Thermal behaviour of geopolymers prepared using class F fly ash and elevated temperature curing

    Energy Technology Data Exchange (ETDEWEB)

    T. Bakharev [Monash University, Clayton, Vic. (Australia). Department of Civil Engineering

    2006-06-15

    This article reports a study of thermal stability of properties upon firing at 800-1200{sup o}C of geopolymer materials prepared using class F fly ash and Na and K alkaline activators. Compressive strength and shrinkage measurements, XRD, SEM (BEI), TGA and MIP were utilised in these studies. The materials were prepared at water/binder ratios in a range of 0.09-0.35, using compaction pressures up to 10 MPa and curing temperatures 80 and 100{sup o}C. Thermal stability of the studied geopolymer materials was rather low. In the samples prepared using sodium-containing activators rapid deterioration of strength at 800{sup o}C was observed, which was connected to a dramatic increase of the average pore size. Initially amorphous structures were replaced by the crystalline Na-feldspars. In materials prepared using fly ash and potassium silicate compressive strength was significantly increased on heating, deterioration of strength started at 1000{sup o}C. After firing these materials remained amorphous with reduced average pore size and significantly increased compressive strength. Compaction at 1-10 MPa reduced shrinkage on firing in all materials. Geopolymer materials prepared using class F fly ash and alkaline activators showed high shrinkage as well as large changes in compressive strength with increasing fired temperature in the range of 800-1200{sup o}C. Thus the materials were found unsuitable for refractory insulation applications.

  19. On the explicit integration of a class of linearizable mappings

    International Nuclear Information System (INIS)

    We examine a class of second-order mappings which can be integrated by reduction to a linear equation. These mappings have been identified in our previous works where we have precisely shown how to obtain their linearization. The mappings belonging to this class are referred to as ‘linearizable mappings of the third kind’. We construct their explicit solution and obtain, for all of them, an invariant of QRT aspect but which is non-autonomous. We show that some of these ‘third-kind’ mappings are related to another class of linearizable mappings, known as mappings of Gambier type, from which they are obtained through a (discrete) derivative with respect to a parameter. (paper)

  20. HLA class I and class II haplotypes in admixed families from several regions of Mexico.

    Science.gov (United States)

    Barquera, Rodrigo; Zúñiga, Joaquín; Hernández-Díaz, Raquel; Acuña-Alonzo, Victor; Montoya-Gama, Karla; Moscoso, Juan; Torres-García, Diana; García-Salas, Claudia; Silva, Beatriz; Cruz-Robles, David; Arnaiz-Villena, Antonio; Vargas-Alarcón, Gilberto; Granados, Julio

    2008-02-01

    We studied HLA class I and class II alleles in 191 Mexican families (381 non-related individuals) to directly obtain the HLA-A/B/DRB1/DQB1 haplotypes and their linkage disequilibrium (LD). The most frequent HLA haplotypes observed were: A*02-B*39-DRB1*04-DQB1*0302, A*02-B*35-DRB1*04-DQB1*0302, A*68-B*39-DRB1*04-DQB1*0302, A*02-B*35-DRB1*08-DQB1*04, A*33-B*1402-DRB1*01-DQB1*05, and A*24-B*35-DRB1*04-DQB1*0302. The four most common haplotypes found by our study involve those previously reported in Amerindian populations. LD analysis of HLA-A-B and HLA-B-DRB1 loci showed significant associations between A29(19)-B44(12), A33(19)-B65(14), A1-B8, A26(19)-B44(12), A24(9)-B61(40), B65(14)-DR1, B8-DR17(3), B44(12)-DR7, B7-DR15(2), and B39(16)-DR4. Also, all DRB1-DQB1 associations showed significant LD values. Admixture estimations using a trihybrid model showed that Mexicans from the State of Sinaloa (Northern Mexico) have a greater proportion of European genetic component compared with Mexicans from the Central area of Mexico, who have a greater percentage of Amerindian genes. Our results are important for future comparative genetic studies of different Mexican ethnic groups with special relevance to disease association and transplantation studies. PMID:17904223