WorldWideScience

Sample records for neuroethologically formative periods

  1. The neuroethology of friendship.

    Science.gov (United States)

    Brent, Lauren J N; Chang, Steve W C; Gariépy, Jean-François; Platt, Michael L

    2014-05-01

    Friendship pervades the human social landscape. These bonds are so important that disrupting them leads to health problems, and difficulties forming or maintaining friendships attend neuropsychiatric disorders like autism and depression. Other animals also have friends, suggesting that friendship is not solely a human invention but is instead an evolved trait. A neuroethological approach applies behavioral, neurobiological, and molecular techniques to explain friendship with reference to its underlying mechanisms, development, evolutionary origins, and biological function. Recent studies implicate a shared suite of neural circuits and neuromodulatory pathways in the formation, maintenance, and manipulation of friendships across humans and other animals. Health consequences and reproductive advantages in mammals additionally suggest that friendship has adaptive benefits. We argue that understanding the neuroethology of friendship in humans and other animals brings us closer to knowing fully what it means to be human. © 2013 New York Academy of Sciences.

  2. The neuroethology of friendship

    Science.gov (United States)

    Brent, Lauren J.N.; Chang, Steve W.C.; Gariépy, Jean-François; Platt, Michael L.

    2014-01-01

    Friendship pervades the human social landscape. These bonds are so important that disrupting them leads to health problems, and difficulties forming or maintaining friendships attend neuropsychiatric disorders like autism and depression. Other animals also have friends, suggesting that friendship is not solely a human invention but is instead an evolved trait. A neuroethological approach applies behavioral, neurobiological, and molecular techniques to explain friendship in terms of its underlying mechanisms, development, evolutionary origins, and biological function. Recent studies implicate a shared suite of neural circuits and neuromodulatory pathways in the formation, maintenance, and manipulation of friendships across humans and other animals. Health consequences and reproductive advantages in mammals additionally suggest that friendship has adaptive benefits. We argue that understanding the neuroethology of friendship in humans and other animals brings us closer to knowing fully what it means to be human. PMID:24329760

  3. The neuroethology of friendship

    OpenAIRE

    Brent, Lauren J. N.; Chang, Steve W.C.; Gariépy, Jean-François; Platt, Michael L.

    2013-01-01

    Friendship pervades the human social landscape. These bonds are so important that disrupting them leads to health problems, and difficulties forming or maintaining friendships attend neuropsychiatric disorders like autism and depression. Other animals also have friends, suggesting that friendship is not solely a human invention but is instead an evolved trait. A neuroethological approach applies behavioral, neurobiological, and molecular techniques to explain friendship in terms of its underl...

  4. 12th International Congress of Neuroethology

    Science.gov (United States)

    2016-10-14

    Zuzana Musilova ABSTRACT TITLE POSTER How does larval growth affect fruit fly vision and flight Pl-112 behavior’ Neural summation in the hawkmoth...edition of the International Congress of Neuroethology. It has been a fruitful 30-year journey for Neuroethology, since the first congress of our...of neocortical circuits (or how to make a mammalian brain) Dr. Rodrigo Suarez, Queensland Brain Institute, The University of Queensland , Austra lia

  5. Decision making: the neuroethological turn

    Science.gov (United States)

    Pearson, John M.; Watson, Karli K.; Platt, Michael L.

    2014-01-01

    Neuroeconomics applies models from economics and psychology to inform neurobiological studies of choice. This approach has revealed neural signatures of concepts like value, risk, and ambiguity, which are known to influence decision-making. Such observations have led theorists to hypothesize a single, unified decision process that mediates choice behavior via a common neural currency for outcomes like food, money, or social praise. In parallel, recent neuroethological studies of decision-making have focused on natural behaviors like foraging, mate choice, and social interactions. These decisions strongly impact evolutionary fitness and thus are likely to have played a key role in shaping the neural circuits that mediate decision-making. This approach has revealed a suite of computational motifs that appear to be shared across a wide variety of organisms. We argue that the existence of deep homologies in the neural circuits mediating choice may have profound implications for understanding human decision-making in health and disease. PMID:24908481

  6. Looking for complexity in quantitative semiology of frontal and temporal lobe seizures using neuroethology and graph theory.

    Science.gov (United States)

    Bertti, Poliana; Tejada, Julian; Martins, Ana Paula Pinheiro; Dal-Cól, Maria Luiza Cleto; Terra, Vera Cristina; de Oliveira, José Antônio Cortes; Velasco, Tonicarlo Rodrigues; Sakamoto, Américo Ceiki; Garcia-Cairasco, Norberto

    2014-09-01

    Epileptic syndromes and seizures are the expression of complex brain systems. Because no analysis of complexity has been applied to epileptic seizure semiology, our goal was to apply neuroethology and graph analysis to the study of the complexity of behavioral manifestations of epileptic seizures in human frontal lobe epilepsy (FLE) and temporal lobe epilepsy (TLE). We analyzed the video recordings of 120 seizures of 18 patients with FLE and 28 seizures of 28 patients with TLE. All patients were seizure-free >1 year after surgery (Engel Class I). All patients' behavioral sequences were analyzed by means of a glossary containing all behaviors and analyzed for neuroethology (Ethomatic software). The same series were used for graph analysis (CYTOSCAPE). Behaviors, displayed as nodes, were connected by edges to other nodes according to their temporal sequence of appearance. Using neuroethology analysis, we confirmed data in the literature such as in FLE: brief/frequent seizures, complex motor behaviors, head and eye version, unilateral/bilateral tonic posturing, speech arrest, vocalization, and rapid postictal recovery and in the case of TLE: presence of epigastric aura, lateralized dystonias, impairment of consciousness/speech during ictal and postictal periods, and development of secondary generalization. Using graph analysis metrics of FLE and TLE confirmed data from flowcharts. However, because of the algorithms we used, they highlighted more powerfully the connectivity and complex associations among behaviors in a quite selective manner, depending on the origin of the seizures. The algorithms we used are commonly employed to track brain connectivity from EEG and MRI sources, which makes our study very promising for future studies of complexity in this field. Copyright © 2014 Elsevier Inc. All rights reserved.

  7. Robot design from a neuro-ethological point of view. Shinkei kodogaku kara mita robot

    Energy Technology Data Exchange (ETDEWEB)

    Shimozawa, T. (Hokkaido Univ., Sapporo (Japan). Research Inst. of Applied Electricity)

    1991-11-01

    The science concerning the method of obtaining the desirable information by adjusting the controllable quantity based on the measurement of the uncontrollable quantity is called cybernetics. The cybernetics is the most ideal image of the robot. The instinct of animals is supported by the nervous system. The science which deals with the nervous system of animals as a function of its instinct is called the neuro-ethology. In this sense, the neuro-ethology is identical to the cybernetics. The fundamental basis of robot design the design of the robot is therefore the neuro-ethology. The treatment of the dependent information about space and time in the auditory nervous system of animals was reviewed. The petuliarity of the auditory system, auditory as an interferometry, and the evolution of the auditory system was explained by taking the sonner system in bats as a prototype of the auditory system of animal. For further explanation of auditory system, the correspondence to the phonetic recognition of Homo-sapiens was also reviewed. It is important for design of the robot to investigate the mechanism to extract informations of the auditory nervous system in animals including Homo-sapiens. 19 refs., 10 figs.

  8. From sequence to spike to spark: evo-devo-neuroethology of electric communication in mormyrid fishes.

    Science.gov (United States)

    Carlson, Bruce A; Gallant, Jason R

    2013-09-01

    Mormyrid fishes communicate using pulses of electricity, conveying information about their identity, behavioral state, and location. They have long been used as neuroethological model systems because they are uniquely suited to identifying cellular mechanisms for behavior. They are also remarkably diverse, and they have recently emerged as a model system for studying how communication systems may influence the process of speciation. These two lines of inquiry have now converged, generating insights into the neural basis of evolutionary change in behavior, as well as the influence of sensory and motor systems on behavioral diversification and speciation. Here, we review the mechanisms of electric signal generation, reception, and analysis and relate these to our current understanding of the evolution and development of electromotor and electrosensory systems. We highlight the enormous potential of mormyrids for studying evolutionary developmental mechanisms of behavioral diversification, and make the case for developing genomic and transcriptomic resources. A complete mormyrid genome sequence would enable studies that extend our understanding of mormyrid behavior to the molecular level by linking morphological and physiological mechanisms to their genetic basis. Applied in a comparative framework, genomic resources would facilitate analysis of evolutionary processes underlying mormyrid diversification, reveal the genetic basis of species differences in behavior, and illuminate the origins of a novel vertebrate sensory and motor system. Genomic approaches to studying the evo-devo-neuroethology of mormyrid communication represent a deeply integrative approach to understanding the evolution, function, development, and mechanisms of behavior.

  9. Claw asymmetry in lobsters: case study in developmental neuroethology.

    Science.gov (United States)

    Govind, C K

    1992-12-01

    An enduring debate in the study of development is the relative contribution of genetic and epigenetic factors in the genesis of an organism, that is, the nature vs. nurture debate. The behavior of the paired claws in the lobster offers promising material for pursuing this debate because of the way they develop. The paired claws and their closer muscles are initially symmetrical; both are slender in appearance and have a mixture of fast and slow fibers in their closer muscles. During a critical period of development, they become determined into a major (crusher) and minor (cutter) claw and during subsequent development acquire their final form and behavior: The crusher becomes a stout, molar-toothed claw capable of closing only slowly because its closer muscle has 100% slow fibers while the cutter becomes a slender, incisor-toothed claw capable of closing rapidly because its closer muscle has 90% fast fibers. Our initial hypothesis was that the more active claw became the crusher and its less active counterpart the cutter. Presumably, nerve activity would influence muscle transformation, which in turn would influence the exoskeleton to which they attach and hence claw morphology. Curtailing nerve activity to the claw prevented crusher development, while reflex activation of a claw promoted its development; both results support the notion that nerve activity directly regulates claw form and function. This is not, however, the case, for when both claws were reflexly exercised neither formed a crusher, signifying rather that bilateral differences in predominantly mechanoreceptive input to the paired claws somehow lateralized the claw ganglion [central nervous system (CNS)] into a crusher and cutter side. The side experiencing the greater activity becomes the crusher side while the contralateral side becomes the cutter and is also inhibited from ever becoming a crusher. This initial lateralization in the CNS is expressed, via as yet unknown pathways, at the periphery in

  10. Pathways in the emergence of developmental neuroethology: antecedents to current views of neurobehavioral ontogeny.

    Science.gov (United States)

    Oppenheim, R W

    1992-12-01

    The historical forces that have contributed to our current views of neurobehavioral development (and thus to the fields of developmental psychobiology and neuroethology) are many and varied. Although similar statements might be made about almost any field of science, it is in particular true of this field, which represents a kind of mongrel discipline derived from at least three major sources (psychology, embryology, and neuroscience) and several more minor ones (including developmental psychology and psychiatry, psychoanalysis, education, zoology, ethology, and sociology). Although I attempt to demonstrate here how each of these sources may have influenced the emergence of a unified field of developmental psychobiology or developmental neuroethology, because the present article represents the first attempt of which I am aware to trace the history of these fields I am certain that there is considerable room for improvement, correction, and revision of the views expressed here. Accordingly, I consider this inaugural effort a kind of reconnaissance intended to trace a necessarily imperfect historic path for others to follow and improve upon. In the final analysis, I will be satisfied if this article only serves to underscore two related points: first is the value derived from historical studies of contemporary issues in development, and the second concerns the extent to which our current ideas and concepts about neurobehavioral development, ideas often considered new and contemporary, were already well known to those who came before us. The first point underscores the arguments expressed in the Introduction that the present must always be reconciled with the past, for the past is never entirely past. The second point returns full circle to an important thought expressed in the opening quotation to this article, namely, that even though our historic predecessors lacked much of the empirical facts available to us they were nonetheless able to attain a surprisingly deep

  11. Formation of charged ferroelectric domain walls with controlled periodicity.

    Science.gov (United States)

    Bednyakov, Petr S; Sluka, Tomas; Tagantsev, Alexander K; Damjanovic, Dragan; Setter, Nava

    2015-10-30

    Charged domain walls in proper ferroelectrics were shown recently to possess metallic-like conductivity. Unlike conventional heterointerfaces, these walls can be displaced inside a dielectric by an electric field, which is of interest for future electronic circuitry. In addition, theory predicts that charged domain walls may influence the electromechanical response of ferroelectrics, with strong enhancement upon increased charged domain wall density. The existence of charged domain walls in proper ferroelectrics is disfavoured by their high formation energy and methods of their preparation in predefined patterns are unknown. Here we develop the theoretical background for the formation of charged domain walls in proper ferroelectrics using energy considerations and outline favourable conditions for their engineering. We experimentally demonstrate, in BaTiO3 single crystals the controlled build-up of high density charged domain wall patterns, down to a spacing of 7 μm with a predominant mixed electronic and ionic screening scenario, hinting to a possible exploitation of charged domain walls in agile electronics and sensing devices.

  12. Periodic fluctuations in deep water formation due to sea ice

    Science.gov (United States)

    Saha, R.

    2012-12-01

    During the last ice age, several abrupt warming events took place, known as Dansgaard-Oeschger (D-O) events. Their effects were felt globally, although the North Atlantic experienced the largest temperature increase. The leading hypothesis to explain their occurrence postulates that the warming was caused by abrupt disruptions of the North Atlantic Current due to meltwater discharge from destabilized ice sheets (Heinrich events). However, the number of warming events outnumber the those of ice-sheet collapse. Thus, the majority of D-O events are not attributed to surface freshwater anomalies, and the underlying mechanism behind their occurrence remain unexplained. Using a simple dynamical model of sea ice and an overturning circulation, I show the existence of self-sustained relaxation oscillations in the overturning circulation. The insulating effect of sea ice is shown to paradoxically lead to a net loss of heat from the top layer of the polar ocean when sea ice retreats. Repeated heat loss results in a denser top layer and a destabilized water column, which triggers convection. The convective state pulls the system out of its preferred mode of circulation, setting up relaxation oscillations. The period of oscillations in this case is linked to the geometry of the ocean basin, if solar forcing is assumed to remain constant. If appropriate glacial freshwater forcing is applied to the model, a pattern of oscillation is produced that bears remarkable similarity to the observed fluctuations in North Atlantic climate between 50,000 and 30,000 years before present.; Comparison of NGRIP δ 18-O (proxy for near surface air temperature) between 50,000 and 30,000 years before present, showing Bond cycles (left) with the model output when forced with appropriate glacial freshwater forcing (right).

  13. BIRDS AS A MODEL TO STUDY ADULT NEUROGENESIS: BRIDGING EVOLUTIONARY, COMPARATIVE AND NEUROETHOLOGICAL APPROCHES

    Science.gov (United States)

    BARNEA, ANAT; PRAVOSUDOV, VLADIMIR

    2011-01-01

    During the last few decades evidence has demonstrated that adult neurogenesis is a well-preserved feature throughout the animal kingdom. In birds, ongoing neuronal addition occurs rather broadly, to a number of brain regions. This review describes adult avian neurogenesis and neuronal recruitment, discusses factors that regulate these processes, and touches upon the question of their genetic control. Several attributes make birds an extremely advantageous model to study neurogenesis. First, song learning exhibits seasonal variation that is associated with seasonal variation in neuronal turnover in some song control brain nuclei, which seems to be regulated via adult neurogenesis. Second, food-caching birds naturally use memory-dependent behavior in learning locations of thousands of food caches scattered over their home ranges. In comparison with other birds, food-caching species have relatively enlarged hippocampi with more neurons and intense neurogenesis, which appears to be related to spatial learning. Finally, migratory behavior and naturally occurring social systems in birds also provide opportunities to investigate neurogenesis. Such diversity of naturally-occurring memory-based behaviors, combined with the fact that birds can be studied both in the wild and in the laboratory, make them ideal for investigation of neural processes underlying learning. This can be done by using various approaches, from evolutionary and comparative to neuroethological and molecular. Finally, we connect the avian arena to a broader view by providing a brief comparative and evolutionary overview of adult neurogenesis and by discussing the possible functional role of the new neurons. We conclude by indicating future directions and possible medical applications. PMID:21929623

  14. Validation of the periodicity of growth zone formation in the otoliths ...

    African Journals Online (AJOL)

    Validation of the periodicity of growth zone formation in the otoliths of four fish species from the Upper Zambezi ecoregion, southern Africa. Geraldine C. Taylor, Richard A. Peel, Clinton J. Hay, Olaf L.F. Weyl ...

  15. Mechanisms of femtosecond LIPSS formation induced by periodic surface temperature modulation

    Energy Technology Data Exchange (ETDEWEB)

    Gurevich, Evgeny L., E-mail: gurevich@lat.rub.de

    2016-06-30

    Highlights: • Possible mechanisms of LIPSS formation by single fs-laser ablation are considered. • We suppose that the surface temperature profile is periodically modulated. • Hydrodynamic instabilities transform the temperature to the height profile. • LIPSS cannot appear due to convection induced by either gravity or surface tension. • Ablative instabilities can explain the LIPSS formation. - Abstract: Here we analyze the formation of laser-induced periodic surface structures (LIPSS) on metal surfaces upon single femtosecond laser pulses. Most of the existing models of the femtosecond LIPSS formation discuss only the appearance of a periodic modulation of the electron and ion temperatures. However the mechanism how the inhomogeneous surface temperature distribution induces the periodically-modulated surface profile under the conditions corresponding to ultrashort-pulse laser ablation is still not clear. Estimations made on the basis of different hydrodynamic instabilities allow to sort out mechanisms, which can bridge the gap between the temperature modulation and the LIPSS. The proposed theory shows that the periodic structures can be generated by single ultrashort laser pulses due to ablative instabilities. The Marangoni and Rayleigh–Bénard convection on the contrary cannot cause the LIPSS formation.

  16. Epicatechin, a component of dark chocolate, enhances memory formation if applied during the memory consolidation period

    OpenAIRE

    Fernell, Maria; Swinton, Cayley; Lukowiak, Ken

    2016-01-01

    ABSTRACT Epicatechin (Epi), a flavanol found in foods such as dark chocolate has previously been shown to enhance memory formation in our model system, operant conditioning of aerial respiration in Lymnaea. In those experiments snails were trained in Epi. Here we ask whether snails exposed to Epi before training, during the consolidation period immediately following training, or 1?h after training would enhance memory formation. We report here that Epi is only able to enhance memory if snails...

  17. SUBWAVELENGTH PERIODIC RIPPLE FORMATION ON GaN SURFACE BY FEMTOSECOND LASER PULSES

    OpenAIRE

    Wang, X.C.; G. C. Lim; F. L. NG; W.; Liu; Chua, S. J.

    2005-01-01

    The formation of femtosecond pulsed laser-induced periodic surface structure on GaN is reported for the first time (to our knowledge) in this paper. It has been found that the formation of the laser-induced ripples is very much dependent and quite sensitive to the laser conditions of the incident laser beam energy fluence and pulse numbers. Possibly due to the unique property of high-defect density of GaN material, the process window for laser-induced ripple formation is quite narrow compared...

  18. Cosmos and Rulership: The Function of Olmec-Style Symbols in Formative Period Mesoamerica.

    Science.gov (United States)

    Reilly, F. Kent III

    1990-01-01

    States that iconographic investigations of Olmec style art works have produced convincing evidence that rulership during the Early and Middle Formative Period of Mesoamerican prehistory was publicly legitimized by a visual charter. Shows that the charter's naturally derived symbols functioned within a system which stressed the human ruler's access…

  19. Crossover between Spatially Confined Precipitation and Periodic Pattern Formation in Reaction Diffusion Systems

    Science.gov (United States)

    López Cabarcos, E.; Kuo, Chein-Shiu; Scala, A.; Bansil, R.

    1996-09-01

    We have observed a crossover between a spatially confined precipitation regime and periodic pattern formation regime. This unusual behavior was observed when electrolyte solutions of Na2HPO4 and CaCl2 were allowed to diffuse into an agarose gel from opposite ends. The formation of the confined precipitate occurs when the electrolyte flux J is the same at both sides of the gel. The time of formation and the width of the precipitate are a function of J and both follow the scaling relation ω~\\(J/D\\)-β with β = 0.40+/-0.2 and D the diffusion coefficient. The growth of periodic bands of precipitate was observed when J was different at both gel ends.

  20. Spectroscopic studies of wood fossils from the Crato Formation, Cretaceous Period.

    Science.gov (United States)

    da Silva, J H; Freire, P T C; Abagaro, B T O; Silva, J A F; Saraiva, G D; de Lima, F J; Barros, O A; Bantim, R A; Saraiva, A A F; Viana, B C

    2013-11-01

    In this work we study two types of wood fossils (Gymnosperms, Araucariaceae) from the Crato Formation of Araripe Basin in Brazil, from the Cretaceous Period. The samples were characterized by Raman and infrared spectroscopies, X-ray diffraction and scanning electron microscopy. The results obtained by different techniques showed that although the rocks surrounding the fossils have predominantly the same constitution - calcite - however, the formation processes of these types of wood fossils are quite different. One of the fossils, denominated as light wood, is predominantly composed of gypsum, while the other fossil, the dark wood, is rich in amorphous carbon, possibly the kerogen type. Implications relative to the environment where the plants lived millions years ago are also given. Finally, the results highlight the constitution of one of the most important paleontological sites of the Cretaceous Period in the South America. Copyright © 2013 Elsevier B.V. All rights reserved.

  1. Spectroscopic studies of wood fossils from the Crato Formation, Cretaceous Period

    Science.gov (United States)

    da Silva, J. H.; Freire, P. T. C.; Abagaro, B. T. O.; Silva, J. A. F.; Saraiva, G. D.; de Lima, F. J.; Barros, O. A.; Bantim, R. A.; Saraiva, A. A. F.; Viana, B. C.

    2013-11-01

    In this work we study two types of wood fossils (Gymnosperms, Araucariaceae) from the Crato Formation of Araripe Basin in Brazil, from the Cretaceous Period. The samples were characterized by Raman and infrared spectroscopies, X-ray diffraction and scanning electron microscopy. The results obtained by different techniques showed that although the rocks surrounding the fossils have predominantly the same constitution - calcite - however, the formation processes of these types of wood fossils are quite different. One of the fossils, denominated as light wood, is predominantly composed of gypsum, while the other fossil, the dark wood, is rich in amorphous carbon, possibly the kerogen type. Implications relative to the environment where the plants lived millions years ago are also given. Finally, the results highlight the constitution of one of the most important paleontological sites of the Cretaceous Period in the South America.

  2. Formation and Properties of Laser-Induced Periodic Surface Structures on Different Glasses

    Directory of Open Access Journals (Sweden)

    Stephan Gräf

    2017-08-01

    Full Text Available The formation and properties of laser-induced periodic surface structures (LIPSS was investigated on different technically relevant glasses including fused silica, borosilicate glass, and soda-lime-silicate glass under irradiation of fs-laser pulses characterized by a pulse duration τ = 300 fs and a laser wavelength λ = 1025 nm. For this purpose, LIPSS were fabricated in an air environment at normal incidence with different laser peak fluence, pulse number, and repetition frequency. The generated structures were characterized by using optical microscopy, scanning electron microscopy, focused ion beam preparation and Fast-Fourier transformation. The results reveal the formation of LIPSS on all investigated glasses. LIPSS formation on soda-lime-silicate glass is determined by remarkable melt-formation as an intra-pulse effect. Differences between the different glasses concerning the appearing structures, their spatial period and their morphology were discussed based on the non-linear absorption behavior and the temperature-dependent viscosity. The findings facilitate the fabrication of tailored LIPSS-based surface structures on different technically relevant glasses that could be of particular interest for various applications.

  3. Formation of the periotic space during the early fetal period in humans.

    Science.gov (United States)

    Ishikawa, Aoi; Ohtsuki, Sae; Yamada, Shigehito; Uwabe, Chigako; Imai, Hirohiko; Matsuda, Tetsuya; Takakuwa, Tetsuya

    2018-01-02

    The inner ear is a very complicated structure, composed of a bony labyrinth (otic capsule; OC), membranous labyrinth, with a space between them, named the periotic labyrinth or periotic space. We investigated how periotic tissue fluid spaces covered the membranous labyrinth 3-dimensionally, leading to formation of the periotic labyrinth encapsulated in the OC during human fetal development. Digital data sets from magnetic resonance images and phase-contrast X-ray tomography images of 24 inner ear organs from 24 human fetuses from the Kyoto Collection (fetuses in trimesters 1 and 2; crown-rump length: 14.4-197 mm) were analyzed. The membranous labyrinth was morphologically differentiated in samples at the end of the embryonic period (Carnegie stage 23), and had grown linearly to more than 8 times in size during the observation period. The periotic space was first detected at the 35-mm samples, around the vestibule and basal turn of the cochlea, which elongated rapidly to the tip of the cochlea and semicircular ducts, successively, and almost covered the membranous labyrinth at the 115-mm CRL stage or later. In those samples, several ossification centers were detected around the space. This paper thus demonstrated that formation of the membranous labyrinth, periotic space (labyrinth), and ossification of the OC occurs successively, according to an intricate timetable. This article is protected by copyright. All rights reserved. © 2018 Wiley Periodicals, Inc.

  4. FORMATION OF THE PRECONDITIONS FOR THE EMERGENCE OF GENDER PSYCHOLOGY IN MIDDLE AGES PERIOD

    Directory of Open Access Journals (Sweden)

    Veronika Olegovna Mokhova

    2013-10-01

    Full Text Available The main purpose of this article is to analyze the main ideas of the Medieval Period authors in Europe and in Russia, in terms of identifying the most important theses of this historical period for the formation and development of the ideas of gender psychology. It is being considered the role of Christianity and the emergence of the women's education issue in the formation of gender stereotypes. In this article the Middle Ages period is being considered as a separate historical phase for the basic ideas formation in the gender psychology, which is a new approach to the history of gender science. To estimate medieval texts - European and Russian, the method of qualitative content analysis is used, by means of which the most relevant to the period ideas associated with the sexes are identified. For Europe, it inter-sexual features, for Russia - different behavioral requirements of the society associated with sexes. Conclusions contain ideas of the Middle Ages in Europe and in Russia that are relevant to the development and establishment of gender psychology. In Europe: the continuation of the ancient thesis of the initial androgyny of a human being; impact of the woman's education on her ability for development; consideration of sexuality as sinful; the issue of women's emancipation, the declining value of the large numerous families despite of a ban on interference in the reproductive cycle in the middle of the Medieval period. In Russia: the perception of inter-sexual characteristics as defined by the God; unconditional obedience of a woman to her husband; androgyny in the distribution of the farmers’ responsibilities.Objective: To analyze the main ideas of the authors of the Middle Ages in Europe and in Russia, in terms of identifying the significant theses of this historical period for the formation and development of the ideas of the gender psychology.Method of the research work: A qualitative content analysis of the texts by the authors

  5. Probing Planet Formation with APOGEE: A Dichotomy in Planet Orbital-Periods and Stellar Metallicities

    Science.gov (United States)

    Wilson, Robert Forrest; Teske, Johanna; Majewski, Steven R.; Cunha, Katia; Smith, Verne; Souto, Diogo; Bender, Chad; Mahadevan, Suvrath; Troup, Nicholas; ALLENDE PRIETO, CARLOS; Stassun, Keivan G.; Skrutskie, Michael; ALMEIDA, ANDRES; Brinkmann, Jonathan; APOGEE

    2018-01-01

    The Apache Point Observatory Galactic Evolution Experiment (APOGEE) is a near-infrared (1.5-1.7 microns), high resolution (R~22,500), high S/N (>100), spectroscopic survey as part of the Sloan Digital Sky Survey (SDSS). Among the goals of this survey is multi-epoch monitoring of exoplanetary systems discovered by the Kepler mission, resulting in very high S/N (typically a few hundred) observations of Planet-hosting stars. The combined visits and sensitivity of the Sloan 2.5-meter telescope yield stellar parameters for a large number of planet-hosting systems with higher precision (e.g., $\\sigma_{[Fe/H]} earth) exoplanetary systems. In particular, we find that planets with orbital periods P ≤ 8.5 days have statistically more metal-enriched hosts than planets with P > 8.5 days. This dichotomy implies that there may be different formation histories between these two populations. For example, there may be a protoplanetary disk inner-radius (such as the gas co-rotation radius or the dust-sublimation radius) with a metallicity-dependence at the time of planet formation that allows small, rocky planets to either form or migrate closer in to their host star in metal-rich conditions. In addition, based on previous work about the "Evaporation Valley", there is theoretical support that this critical period of 8.5 days may be tied to the bulk composition of the two exoplanet populations.

  6. Chlorination of iodide-containing waters in the presence of CuO: Formation of periodate

    KAUST Repository

    Liu, Chao

    2014-11-18

    It has been shown previously that the disproportionation of halogen-containing oxidants (e.g., HOCl, HOBr, and ClO2) is enhanced by a CuO-catalyzed process. In this study, the transformation of iodine during chlorination in the presence of CuO was investigated. There is no significant enhancement of the disproportionation of hypoiodous acid (HOI) in the presence of CuO. The formation rate of iodate (IO3 -) in the CuO-HOCl-I- system significantly increased when compared to homogeneous solutions, which was ascribed to the activation of HOCl by CuO enhancing its reactivity toward HOI. In this reaction system, iodate formation rates increase with increasing CuO (0-0.5 g L-1) and bromide (0-2 μM) doses and with decreasing pH (9.6-6.6). Iodate does not adsorb to the CuO surfaces used in this study. Nevertheless, iodate concentrations decreased after a maximum was reached in the CuO-HOCl-I-(-Br-) systems. Similarly, the iodate concentrations decrease as a function of time in the CuO-HOCl-IO3 - or CuO-HOBr-IO3 - system, and the rates increase with decreasing pH (9.6-6.6) due to the enhanced reactivity of HOCl or HOBr in the presence of CuO. It could be demonstrated that iodate is oxidized to periodate by a CuO-activated hypohalous acid, which is adsorbed on the CuO surface. No periodate could be measured in filtered solutions because it was mainly adsorbed to CuO. The adsorbed periodate was identified by scanning electron microscopy plus energy dispersive spectroscopy and X-ray photoelectron spectroscopy.

  7. Spontaneous formation of highly periodic nano-ripples in inclined deposition of Mo/Si multilayers

    Science.gov (United States)

    Voronov, D. L.; Gawlitza, P.; Braun, S.; Padmore, H. A.

    2017-09-01

    We investigated the growth of Mo/Si multilayers (ML) deposited using a highly collimated flux of ion-beam sputtered particles for a wide range of deposition angles. Growth of the multilayers at normal and moderately inclined deposition is dominated by surface relaxation resulting in smooth interfaces of the multilayer stack. The first signs of interface roughening are observed at a deposition angle of 45° with respect to the normal to the substrate surface. At an oblique angle of 55°, the ML interfaces undergo fast progressive roughening from the substrate to the top of the ML stack, leading to the formation of ripples which are perpendicular to the deposition flux direction. Deposition of the multilayer at an angle of 65° results in a highly periodic lateral ripple structure with a period of 10 nm. The mature ripple pattern forms during growth of only the first few layers and then stabilizes. The ripples propagate through the whole ML stack with almost no changes in frequency and amplitude, resulting in a highly periodic bulk array composed of silicon and molybdenum nano-rods closely packed in a 6-fold symmetric lattice. We present a simple model for the ripple growth, which gives results that are in good agreement with experimental data.

  8. High contrast periodic plasma pattern formation during the laser-induced breakdown in transparent dielectric

    Science.gov (United States)

    Gildenburg, V. B.; Pavlichenko, I. A.

    2017-12-01

    Based on a simple 1D initial-time model, we have carried out the numerical simulation for the spatio-temporal evolution of femtosecond laser pulse induced breakdown in transparent dielectric (fused silica) at the nonlinear stage of the plasma resonance ionization instability. The instability develops from very small seed perturbations of the medium permittivity and results in, because of the strong mutual enhancement of the electric field and plasma density perturbations in the plasma resonance region, the formation of the subwavelength periodic plasma-field structure consisting of the overcritical plasma layers perpendicular to the laser polarization. The calculation of the time-course and spatial profiles of the plasma density, field amplitude, and energy deposition density in the medium during one breakdown pulse has allowed us to establish the main possible scenarios of the process considered and to found the laser intensity range where this process can underlie the nanograting modification of the medium by repeated pulses.

  9. Cartilage formation in the pelvic skeleton during the embryonic and early-fetal period.

    Directory of Open Access Journals (Sweden)

    Misaki Okumura

    Full Text Available The pelvic skeleton is formed via endochondral ossification. However, it is not known how the normal cartilage is formed before ossification occurs. Furthermore, the overall timeline of cartilage formation and the morphology of the cartilage in the pelvis are unclear. In this study, cartilage formation in the pelvic skeletons of 25 human fetuses (crown-rump length [CRL] = 11.9-75.0 mm was observed using phase-contrast computed tomography and 7T magnetic resonance imaging. The chondrification center of the ilium, ischium, and pubis first appeared simultaneously at Carnegie stage (CS 18, was located around the acetabulum, and grew radially in the later stage. The iliac crest formed at CS20 while the iliac body's central part remained chondrified. The iliac body formed a discoid at CS22. The growth rate was greater in the ilium than in the sacrum-coccyx, pubis, and ischium. Connection and articulation formed in a limited period, while the sacroiliac joint formed at CS21. The articulation of the pubic symphysis, connection of the articular column in the sacrum, and Y-shape connection of the three parts of the hip bones to the acetabulum were observed at CS23; the connection of the ischium and pubic ramus was observed at the early-fetal stage. Furthermore, the degree of connection at the center of the sacrum varied among samples. Most of the pelvimetry data showed a high correlation with CRL. The transverse and antero-posterior lengths of the pelvic inlet of the lesser pelvis varied among samples (R2 = 0.11. The subpubic angle also varied (65-90° and was not correlated with CRL (R2 = 0.22. Moreover, cartilaginous structure formation appeared to influence bone structure. This study provides valuable information regarding the morphogenesis of the pelvic structure.

  10. Determining Factors and Critical Periods in the Formation of Eating Habits: Results from the Habeat Project.

    Science.gov (United States)

    Issanchou, Sylvie

    2017-01-01

    Eating habits form early during childhood and are likely to track until the beginning of adulthood. Thus, understanding the formation of eating habits is important. Consequently, the population targeted in the European project Habeat comprised infants and young children up to 6 years of age. Habeat mainly focused on the qualitative dimension of eating habits with a particular attention on vegetables and to a lesser extent on fruit. Food intake of young children was also studied in 2 challenging situations where overeating may occur and the relation between children's behaviour and feeding parental practices was examined. Key Messages: Habeat found evidence that breastfeeding may facilitate the consumption of vegetables and fruit and a greater variety of healthy foods in later childhood. Introduction of a variety of vegetables at the beginning of the complementary feeding period increases later acceptance of novel foods. Repeated exposure is a powerful mechanism to increase children's intake of a novel vegetable in infants and young children. Offering energy-dense snacks before or after meals should be avoided. Moreover, food should be offered to children in response to their feelings of hunger, and not used as reward for a good behaviour or for any other reason. © 2017 S. Karger AG, Basel.

  11. Neuroethologic differences in sleep deprivation induced by the single- and multiple-platform methods

    Directory of Open Access Journals (Sweden)

    R. Medeiros

    1998-05-01

    Full Text Available It has been proposed that the multiple-platform method (MP for desynchronized sleep (DS deprivation eliminates the stress induced by social isolation and by the restriction of locomotion in the single-platform (SP method. MP, however, induces a higher increase in plasma corticosterone and ACTH levels than SP. Since deprivation is of heuristic value to identify the functional role of this state of sleep, the objective of the present study was to determine the behavioral differences exhibited by rats during sleep deprivation induced by these two methods. All behavioral patterns exhibited by a group of 7 albino male Wistar rats submitted to 4 days of sleep deprivation by the MP method (15 platforms, spaced 150 mm apart and by 7 other rats submitted to sleep deprivation by the SP method were recorded in order to elaborate an ethogram. The behavioral patterns were quantitated in 10 replications by naive observers using other groups of 7 rats each submitted to the same deprivation schedule. Each quantification session lasted 35 min and the behavioral patterns presented by each rat over a period of 5 min were counted. The results obtained were: a rats submitted to the MP method changed platforms at a mean rate of 2.62 ± 1.17 platforms h-1 animal-1; b the number of episodes of noninteractive waking patterns for the MP animals was significantly higher than that for SP animals (1077 vs 768; c additional episodes of waking patterns (26.9 ± 18.9 episodes/session were promoted by social interaction in MP animals; d the cumulative number of sleep episodes observed in the MP test (311 was significantly lower (chi-square test, 1 d.f., P<0.05 than that observed in the SP test (534; e rats submitted to the MP test did not show the well-known increase in ambulatory activity observed after the end of the SP test; f comparison of 6 MP and 6 SP rats showed a significantly shorter latency to the onset of DS in MP rats (7.8 ± 4.3 and 29.0 ± 25.0 min, respectively

  12. Modelling periodic structure formation on 100Cr6 steel after irradiation with femtosecond-pulsed laser beams

    Science.gov (United States)

    Tsibidis, George D.; Mimidis, Alexandros; Skoulas, Evangelos; Kirner, Sabrina V.; Krüger, Jörg; Bonse, Jörn; Stratakis, Emmanuel

    2018-01-01

    We investigate the periodic structure formation upon intense femtosecond pulsed irradiation of chrome steel (100Cr6) for linearly polarised laser beams. The underlying physical mechanism of the laser-induced periodic structures is explored, their spatial frequency is calculated and theoretical results are compared with experimental observations. The proposed theoretical model comprises estimations of electron excitation, heat transfer, relaxation processes, and hydrodynamics-related mass transport. Simulations describe the sequential formation of sub-wavelength ripples and supra-wavelength grooves. In addition, the influence of the laser wavelength on the periodicity of the structures is discussed. The proposed theoretical investigation offers a systematic methodology towards laser processing of steel surfaces with important applications.

  13. Visualization of hot spot formation in energetic materials under periodic mechanical excitation using phosphor thermography

    Science.gov (United States)

    Casey, Alex; Fenoglio, Gabriel; Detrinidad, Humberto

    2017-06-01

    Under mechanical excitation, energy is known to localize within an energetic material resulting in `hot spot' formation. While many formation mechanisms have been proposed, additional insight to heat generation mechanisms, the effect of binder/crystal interfaces, and predication capabilities can be gained by quantifying the initiation and growth of the hot spots. Phosphor thermography is a well established temperature sensing technique wherein an object's temperature is obtained by collecting the temperature dependent luminescence of an optically excited phosphor. Herein, the phosphor thermography technique has been applied to Dow Corning Sylgard® 184/octahydro 1,3,5,7 tetranitro 1,3,5,7 tetrazocine (HMX) composite materials under mechanical excitation in order to visualize the evolution of the temperature field, and thus hot spot formation, within the binder. Funded by AFOSR. Supported by the Department of Defense (DoD) through the National Defense Science & Engineering Graduate Fellowship (NDSEG) Program.

  14. Spectroscopic studies of the fish fossils (Cladocyclus gardneri and Vinctifer comptoni) from the Ipubi Formation of the Cretaceous Period.

    Science.gov (United States)

    Sousa Filho, F E; da Silva, J H; Saraiva, G D; Abagaro, B T O; Barros, O A; Saraiva, A A F; Viana, B C; Freire, P T C

    2016-03-15

    Fossils are mineralized remains or traces from animals, plants and other organisms aged to about 10(8)years. The chemical processes of fossilization are dated back from old geological periods on Earth. The understanding of these processes and the structure of the fossils are one of the goals of paleontology and geology in the sedimentary environments. Many researches have tried to unveil details about special kinds of biological samples; however, a lack of data is noticed for various other specimens. This study reports the investigations through infrared spectroscopy, X-ray fluorescence and X-ray diffraction measurements for two types of fish fossils from the Cretaceous Period. The sample of Cladocyclus gardneri and Vinctifer comptoni fossils were collected from the Ipubi Formation, being one of the less studied, among the formations that constitute the important Santana group in the Araripe Basin, Brazil. The results obtained through different techniques, showed that the C. gardneri fish fossil contains hydroxyapatite and calcite as constituents whereas its rock matrix was formed by calcite, quartz and pyrite. Regarding the V. comptoni, the measurements confirmed the presence of hydroxyapatite in the fossil and its rock matrix gypsum, pyrite, quartz and calcite. The above scientific data contributed to the understanding the fossil formation in the Ipubi Formation, an important environment of the Cretaceous Period, which is rich in well-preserved fossils from different species. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. Spectroscopic studies of the fish fossils (Cladocyclus gardneri and Vinctifer comptoni) from the Ipubi Formation of the Cretaceous Period

    Science.gov (United States)

    Sousa Filho, F. E.; da Silva, J. H.; Saraiva, G. D.; Abagaro, B. T. O.; Barros, O. A.; Saraiva, A. A. F.; Viana, B. C.; Freire, P. T. C.

    2016-03-01

    Fossils are mineralized remains or traces from animals, plants and other organisms aged to about 108 years. The chemical processes of fossilization are dated back from old geological periods on Earth. The understanding of these processes and the structure of the fossils are one of the goals of paleontology and geology in the sedimentary environments. Many researches have tried to unveil details about special kinds of biological samples; however, a lack of data is noticed for various other specimens. This study reports the investigations through infrared spectroscopy, X-ray fluorescence and X-ray diffraction measurements for two types of fish fossils from the Cretaceous Period. The sample of Cladocyclus gardneri and Vinctifer comptoni fossils were collected from the Ipubi Formation, being one of the less studied, among the formations that constitute the important Santana group in the Araripe Basin, Brazil. The results obtained through different techniques, showed that the C. gardneri fish fossil contains hydroxyapatite and calcite as constituents whereas its rock matrix was formed by calcite, quartz and pyrite. Regarding the V. comptoni, the measurements confirmed the presence of hydroxyapatite in the fossil and its rock matrix gypsum, pyrite, quartz and calcite. The above scientific data contributed to the understanding the fossil formation in the Ipubi Formation, an important environment of the Cretaceous Period, which is rich in well-preserved fossils from different species.

  16. The neuroethology of friendship

    National Research Council Canada - National Science Library

    Brent, Lauren J.N; Chang, Steve W.C; Gariépy, Jean‐François; Platt, Michael L

    2014-01-01

    Friendship pervades the human social landscape. These bonds are so important that disrupting them leads to health problems, and difficulties forming or maintaining friendships attend neuropsychiatric disorders like autism and depression...

  17. Formation of thermal fatigue cracks in periodic rapid quenching of metal

    Energy Technology Data Exchange (ETDEWEB)

    Ots, A. [Tallinn Technical University, Thermal Engineering Department, Tallinn (Estonia)

    1998-12-31

    Water lancing is an effective technique for cleaning boiler heating surfaces from ash deposits by burning low-grade fuels with complicated composition of mineral matter. In water cleaning cycles of boiler`s heat transfer surfaces due to rapid quenching destruction of corrosion protective oxide film and formation of thermal fatigue cracks on the outer surface of the tube`s metal occur. The criterion of the thermal fatigue cracks` formation and their growth intensity depend on the character of temperature field in the tube`s metal outer layer. The solution of non-stationary heat conductivity equation for metal rapid quenching conditions is given. The convective heat transfer coefficients from hot metal surface to water jet were established experimentally. Thermal fatigue crack growth intensity was investigated in real boilers` heat transfer surfaces` tubes as well as in laboratory conditions. The formula for predicting thermal fatigue cracks` depth depending on the number of cleaning cycles. (orig.) 5 refs.

  18. Periodic modulations controlling Kuznetsov–Ma soliton formation in nonlinear Schrödinger equations

    Energy Technology Data Exchange (ETDEWEB)

    Tiofack, C.G.L., E-mail: glatchio@yahoo.fr [Univ. Lille, CNRS, UMR 8523 – PhLAM – Physique des Lasers Atomes et Molécules, F-59000 Lille (France); Coulibaly, S.; Taki, M. [Univ. Lille, CNRS, UMR 8523 – PhLAM – Physique des Lasers Atomes et Molécules, F-59000 Lille (France); De Bièvre, S.; Dujardin, G. [Univ. Lille, CNRS, UMR 8524 – Laboratoire Paul Painlevé, F-59000 Lille (France); Équipe-Projet Mephysto, INRIA Lille-Nord Europe (France)

    2017-06-28

    We analyze the exact Kuznetsov–Ma soliton solution of the one-dimensional nonlinear Schrödinger equation in the presence of periodic modulations satisfying an integrability condition. We show that, in contrast to the case without modulation, the Kuznetsov–Ma soliton develops multiple compression points whose number, shape and position are controlled both by the intensity of the modulation and by its frequency. In addition, when this modulation frequency is a rational multiple of the natural frequency of the Kuznetsov–Ma soliton, a scenario similar to a nonlinear resonance is obtained: in this case the spatial oscillations of the Kuznetsov–Ma soliton's intensity are periodic. When the ratio of the two frequencies is irrational, the soliton's intensity is a quasiperiodic function. A striking and important result of our analysis is the possibility to suppress any component of the output spectrum of the Kuznetsov–Ma soliton by a judicious choice of the amplitude and frequency of the modulation. - Highlights: • Exact Kuznetsov–Ma soliton solution in presence of periodic coefficients is obtained. • The multiple compression points of the solution are studied. • The quasi-periodicity of the solution is discussed. • The possibility to suppress any component of the spectrum is analyzed.

  19. Resource selection and allocation in dynamic multi-period formation of virtual cell with consideration of multiple processing routes

    Directory of Open Access Journals (Sweden)

    Wenmin Han

    2017-03-01

    Full Text Available To enhance the production continuity and optimal utilization of the Shipbuilding enterprises during multi-period, a multi-object dynamic mixed integer programming model of virtual cell is proposed to complete the resource selection and batch assignment of routes by minimizing the processing cost, transportation cost, scheduling factors and load balance. The factors including constraints on the processing capacity equipment redundancy and the influences of batch processing and cellular formation on scheduling are considered in the model design. This paper proposed improved multi-object genetic algorithm to obtain optimal pareto solution set and introduced TOPSIS to determine the best resource group. The model and algorithm presented is applied in a job shop of pipe in a shipyard. The robust resource selection strategy during multi-period can greatly balance the working load of all shops, and achieve more superior structure of virtual cell formation.

  20. Epitaxial nanowire formation in metamorphic GaAs/GaPAs short-period superlattices

    Science.gov (United States)

    Zheng, Nan; Ahrenkiel, S. Phillip

    2017-07-01

    Metamorphic growth presents routes to novel nanomaterials with unique properties that may be suitable for a range of applications. We discuss self-assembled, epitaxial nanowires formed during metalorganic chemical vapor deposition of metamorphic GaAs/GaPAs short-period superlattices. The heterostructures incorporate strain-engineered GaPAs compositional grades on 6°-B miscut GaAs substrates. Lateral diffusion within the SPS into vertically aligned, three-dimensional columns results in nanowires extending along A directions with a lateral period of 70-90 nm. The microstructure is probed by transmission electron microscopy to confirm the presence of coherent GaAs nanowires within GaPAs barriers. The compositional profile is inferred from analysis of {200} dark-field image contrast and lattice images.

  1. The influence of canon law on ius commune in its formative period

    OpenAIRE

    Mehmeti Sami

    2015-01-01

    In the Medieval period, Roman law and canon law formed ius commune or the common European law. The similarity between Roman and canon law was that they used the same methods and the difference was that they relied on different authoritative texts. In their works canonists and civilists combined the ancient Greek achievements in philosophy with the Roman achievements in the field of law. Canonists were the first who carried out research on the distinctions between various legal sources and sys...

  2. Case-control study of the PERIOD3 clock gene length polymorphism and colorectal adenoma formation

    OpenAIRE

    ALEXANDER, MELANNIE; Burch, James B.; Steck, Susan E.; Chen, Chin-Fu; Hurley, Thomas G.; Cavicchia, Philip; Ray, Meredith; Shivappa, Nitin; GUESS, JACLYN; Zhang, Hongmei; Youngstedt, Shawn D; Creek, Kim E.; Lloyd, Stephen; Yang, Xiaoming; H?bert, James R.

    2014-01-01

    Clock genes are expressed in a self-perpetuating, circadian pattern in virtually every tissue including the human gastrointestinal tract. They coordinate cellular processes critical for tumor development, including cell proliferation, DNA damage response and apoptosis. Circadian rhythm disturbances have been associated with an increased risk for colon cancer and other cancers. This mechanism has not been elucidated, yet may involve dysregulation of the ?period? (PER) clock genes, which have t...

  3. Formation of organic layer on femtosecond laser-induced periodic surface structures

    Science.gov (United States)

    Yasumaru, Naoki; Sentoku, Eisuke; Kiuchi, Junsuke

    2017-05-01

    Two types of laser-induced periodic surface structures (LIPSS) formed on titanium by femtosecond (fs) laser pulses (λ = 800 nm, τ = 180 fs, ν = 1 kHz) in air were investigated experimentally. At a laser fluence F above the ablation threshold, LIPSS with a minimum mean spacing of D organic thin film similar to a cellulose derivative that cannot be easily formed by conventional chemical synthesis. The results of these surface analyses indicate that these two types of LIPSS are formed through different mechanisms. This fs-laser processing technique may become a new technology for the artificial synthesis of cellulose derivatives.

  4. The influence of canon law on ius commune in its formative period

    Directory of Open Access Journals (Sweden)

    Mehmeti Sami

    2015-12-01

    Full Text Available In the Medieval period, Roman law and canon law formed ius commune or the common European law. The similarity between Roman and canon law was that they used the same methods and the difference was that they relied on different authoritative texts. In their works canonists and civilists combined the ancient Greek achievements in philosophy with the Roman achievements in the field of law. Canonists were the first who carried out research on the distinctions between various legal sources and systematized them according to a hierarchical order. The Medieval civilists sought solutions in canon law for a large number of problems that Justinian’s Codification did not hinge on or did it only superficially. Solutions offered by canon law were accepted not only in the civil law of Continental Europe, but also in the English law.

  5. Formation of organic layer on femtosecond laser-induced periodic surface structures

    Energy Technology Data Exchange (ETDEWEB)

    Yasumaru, Naoki, E-mail: yasuma@fukui-nct.ac.jp [National Institute of Technology, Fukui College, Sabae, Fukui 916-8507 (Japan); Sentoku, Eisuke [National Institute of Technology, Fukui College, Sabae, Fukui 916-8507 (Japan); Kiuchi, Junsuke [Eyetec Co., Ltd., Sabae, Fukui 916-0016 (Japan)

    2017-05-31

    Highlights: • Surface analyses of two types of femtosecond laser-induced periodic surface structures (LIPSS) on titanium were conducted. • The parallel-oriented ultrafine LIPSS showed the almost same roughness and chemical states as the non-irradiated Ti surface. • The well-known perpendicular-oriented LIPSS were typically covered with an organic layer similar to a cellulose derivative. - Abstract: Two types of laser-induced periodic surface structures (LIPSS) formed on titanium by femtosecond (fs) laser pulses (λ = 800 nm, τ = 180 fs, ν = 1 kHz) in air were investigated experimentally. At a laser fluence F above the ablation threshold, LIPSS with a minimum mean spacing of D < λ⁄2 were observed perpendicular to the laser polarization direction. In contrast, for F slightly below than the ablation threshold, ultrafine LIPSS with a minimum value of D < λ/10 were formed parallel to the polarization direction. The surface roughness of the parallel-oriented LIPSS was almost the same as that of the non-irradiated surface, unlike the high roughness of the perpendicular-oriented LIPSS. In addition, although the surface state of the parallel-oriented LIPSS was the same as that of the non-irradiated surface, the perpendicular-oriented LIPSS were covered with an organic thin film similar to a cellulose derivative that cannot be easily formed by conventional chemical synthesis. The results of these surface analyses indicate that these two types of LIPSS are formed through different mechanisms. This fs-laser processing technique may become a new technology for the artificial synthesis of cellulose derivatives.

  6. Laser-induced periodic surface structures formation: investigation of the effect of nonlinear absorption of laser energy in different materials

    Science.gov (United States)

    Levy, Yoann; Bulgakova, Nadezhda M.; Mocek, Tomáš

    2017-05-01

    To get insight into laser-induced periodic surface structures (LIPSS) formation, the relaxation of a modulation in the temperature profile is investigated numerically on surfaces of two different kinds of materials (metals and dielectrics; gold and fused silica as examples) upon irradiation by ultrashort laser pulses. The temperature modulation is assumed to originate from the interference between the incoming laser pulse and the surface electromagnetic wave, which is considered as the main mechanism of LIPSS formation. For comparative studies of laser energy dissipation, a simplified 2D approach is used. It is based on the two-temperature model (TTM) and considers the mechanisms of nonlinear absorption of laser light (multiphoton ionization in fused silica; temperature-dependent thermophysical and optical properties in gold) and relaxation (electron trapping to excitonic states in fused silica). The TTM is coupled with the Drude model, considering the evolution of optical properties as a function of free-carrier density and/or temperature. The development and decay of the lattice temperature modulation, which can govern the LIPSS formation, is followed during electron-lattice thermalization time and beyond. It is shown that strong temperature gradients can form along the surfaces of both kinds of materials under study within the fluence range typical for LIPSS formation. Considerable changes in optical properties of these materials are found as a function of time, including metals, for which a constant reflectivity is usually assumed. Effects of nonlinear absorption on the surface temperature dynamics are reported.

  7. A Late Formative Period Occupation in El Oro, Ecuador: A Case for Ecological Catastrophe?

    Directory of Open Access Journals (Sweden)

    Elizabeth J. Currie

    1992-11-01

    Full Text Available In the early 1970s shrimp farmersbegan an intensive and ecologically controversial exploitation of the coast of El Oro, constructing extensive and intricate systems of banks, dykes and lagoons ('camaroneras' within which to rear large tropical prawns for the international export market. This prawn-breeding industry in some ways represents a commercial elaboration of a process started in prehistory, when the capacity of the marine and mangrove environment to support large populations of people over long periods of time is attested by the numbers and size attained by many of the shell middens. Many consist almost exclusively of a species of large flat oyster ('Crassostera' now unknown to present-day inhabitants of the coast. In 1975 shrimp farmers operating near the mangrove coast to the north of the town of Santa Rosa near the Estero Guaramal, cut a deep profile through a shell mound, exposing the stratigraphy which revealed a clear environmental change, manifested by a replacement of shellfish species.

  8. Laser-induced periodic surface structures formation on mesoporous silicon from nanoparticles produced by picosecond and femtosecond laser shots

    Science.gov (United States)

    Talbi, Abderazek; Kaya-Boussougou, Sostaine; Sauldubois, Audrey; Stolz, Arnaud; Boulmer-Leborgne, Chantal; Semmar, Nadjib

    2017-07-01

    This paper deals with the formation of laser-induced periodic surface structures (LIPSS) on mesoporous silicon thin films induced by two laser regimes in the UV range: picosecond and femtosecond. Different LIPSS formation mechanisms from nanoparticles, mainly coalescence and agglomeration, have been evidenced by scanning electron microscopy analysis. The apparition of a liquid phase during both laser interaction at low fluence (20 mJ/cm2) and after a large number of laser pulses (up to 12,000) has been also shown with 100 nm size through incubation effect. Transmission electron microscopy analyses have been conducted to investigate the molten phase structures below and inside LIPSS. Finally, it has shown that LIPSS are composed of amorphous silicon when mesoporous silicon is irradiated by laser beam in both regimes. Nevertheless, mesoporous silicon located between LIPSS stays crystallized.

  9. Particle number size distribution and new particle formation: new characteristics during the special pollution control period in Beijing.

    Science.gov (United States)

    Gao, Jian; Chai, Fahe; Wang, Tao; Wang, Shulan; Wang, Wenxing

    2012-01-01

    New particle formation is a key process in shaping the size distribution of aerosols in the atmosphere. We present here the measurement results of number and size distribution of aerosol particles (10-10000 nm in diameter) obtained in the summer of 2008, at a suburban site in Beijing, China. We firstly reported the pollution level, particle number size distribution, diurnal variation of the particle number size distribution and then introduced the characteristics of the particle formation processes. The results showed that the number concentration of ultrafine particles was much lower than the values measured in other urban or suburban areas in previous studies. Sharp increases of ultrafine particle count were frequently observed at noon. An examination of the diurnal pattern suggested that the burst of ultrafine particles was mainly due to new particle formation promoted by photochemical processes. In addition, high relative humidity was a key factor driving the growth of the particles in the afternoon. During the 2-month observations, new particle formation from homogeneous nucleation was observed for 42.7% of the study period. The average growth rate of newly formed particles was 3.2 nm/hr, and varied from 1.2 to 8.0 nm/hr. The required concentration of condensable vapor was 4.4 x 10(7) cm(-3), and its source rate was 1.2 x 106 cm(-3) sec(-1). Further calculation on the source rate of sulphuric acid vapor indicated that the average participation of sulphuric acid to particle growth rates was 28.7%.

  10. Formation of laser-induced periodic surface structures (LIPSS) on tool steel by multiple picosecond laser pulses of different polarizations

    Energy Technology Data Exchange (ETDEWEB)

    Gregorčič, Peter, E-mail: peter.gregorcic@fs.uni-lj.si [Faculty of Mechanical Engineering, University of Ljubljana, Aškerčeva 6, 1000 Ljubljana (Slovenia); Sedlaček, Marko; Podgornik, Bojan [Institute of Metals and Technology, Lepi pot 11, 1000 Ljubljana (Slovenia); Reif, Jürgen [Brandenburgische Technische Universitaet – BTU Cottbus-Senftenberg, Platz der Deutschen Einheit 1, 03046 Cottbus (Germany)

    2016-11-30

    Highlights: • Low number of differently polarized ps laser pulses is superimposed on tool steel. • Last pulses determine the ripples orientation for single spot and coherent traces. • Previously formed structures are overridden by later incident pulses. • Ripples contrast depends on total exposure, independent on pulses’ polarization. • Weak role of pre-formed structures makes interference scenarios questionable. - Abstract: Laser-induced periodic surface structures (LIPSS) are produced on cold work tool steel by irradiation with a low number of picosecond laser pulses. As expected, the ripples, with a period of about 90% of the laser wavelength, are oriented perpendicular to the laser polarization. Subsequent irradiation with the polarization rotated by 45° or 90° results in a corresponding rotation of the ripples. This is visible already with the first pulse and becomes almost complete – erasing the previous orientation – after as few as three pulses. The phenomenon is not only observed for single-spot irradiation but also for writing long coherent traces. The experimental results strongly defy the role of surface plasmon-polaritons as the predominant key to LIPSS formation.

  11. Late Noachian Climate Of Mars: Constraints From Valley Network System Formation Times And The Intermittencies (Episodic/Periodic And Punctuated).

    Science.gov (United States)

    Head, James

    2017-04-01

    Formation of Late Noachian-Early Hesperian (LN-EH) valley network systems (VNS) signaled the presence of warm/wet conditions generating several hypotheses for climates permissive of these conditions. To constrain options for the ambient Noachian climate, we examine estimates for time required to carve channels/deltas and total duration implied by plausible intermittencies. Formation Times for VN, OBL, Deltas, Fans: A synthesis of required timescales show that even with the longest estimated continuous duration of VN formation/intermittencies, total time to carve the VN does not exceed 106 years, 273 K, hydrological system vertically integrated, and rainfall occurs to recharge the aquifer. Two subtypes: a) "Rainfall/Fluvial Erosion-Dominated Warm and Wet Model": "Rainfall and surface runoff" persist throughout Noachian to explain crater degradation, and a LN-EH short rapidly ending terminal epoch. b) "Recharge Evaporation/Evaporite Dominated Warm and Wet Model": Sustained period of equatorial/mid-latitude precipitation and a vertically integrated hydrological system driven by evaporative upwelling and fluctuating shallow water table playa environments account for sulfate evaporate environments at Meridiani Planum. Sustained temperatures >273 K are required for extended periods (107-108 years). 2) Cold and icy climate: Sustained background temperatures extremely low (MAT ˜225 K), cryosphere is globally continuous, hydrological system is horizontally stratified, separating groundwater system from surface; no combination of spin-axis/orbital perturbations can raise MAT to 273 K. Adiabatic cooling effects transfer water to high altitudes, leading to "Late Noachian Icy Highlands Model". VNS cannot form in this nominal climate environment without special circumstances (e.g., impacts or volcanic eruptions elevate of temperatures by >˜50 K to induce melting and fluvial/lacustrine activity). 3) Cold and Icy climate warmed by greenhouse gases: The climate is sustained cold

  12. Observations of atmospheric nitrogen and phosphorus deposition during the period of algal bloom formation in northern Lake Taihu, China.

    Science.gov (United States)

    Zhai, Shuijing; Yang, Longyuan; Hu, Weiping

    2009-09-01

    Cyanobacterial blooms in Lake Taihu occurred at the end of April 2007 and had crucial impacts on the livelihood of millions of people living there. Excessive nutrients may promote bloom formation. Atmospheric nitrogen (N) and phosphorus (P) deposition appears to play an important role in algal bloom formation. Bulk deposition and rain water samples were collected respectively from May 1 to November 30, 2007, the period of optimal algal growth, to measure the bulk atmospheric deposition rate, wet deposition rate, and dry deposition rate for total nitrogen (TN; i.e., all species of nitrogen), and total phosphorus (TP; i.e., all species of phosphorus), in northern Lake Taihu, China. The trends of the bulk atmospheric deposition rate for TN and the wet deposition rate for TN showed double peaks during the observation period and distinct influence with plum rains and typhoons. Meanwhile, monthly bulk atmospheric deposition rates for TP showed little influence of annual precipitation. However, excessive rain may lead to high atmospheric N and P deposition rates. In bulk deposition samples, the average percentage of total dissolved nitrogen accounting for TN was 91.2% and changed little with time. However, the average percentage of total dissolved phosphorus accounting for TP was 65.6% and changed substantially with time. Annual bulk atmospheric deposition rates of TN and TP during 2007 in Lake Taihu were estimated to be 2,976 and 84 kg km(-2) a(-1), respectively. The results showed decreases of 34.4% and 78.7%, respectively, compared to 2002-2003. Annual bulk deposition load of TN for Lake Taihu was estimated at 6,958 t a(-1) in 2007 including 4,642 t a(-1) of wet deposition, lower than the values obtained in 2002-2003. This may be due to measures taken to save energy and emission control regulations in the Yangtze River Delta. Nevertheless, high atmospheric N and P deposition loads helped support cyanobacterial blooms in northern Lake Taihu during summer and autumn, the

  13. Formation of periodic mesoscale structures arranged in a circular symmetry at the silicon surface exposed to radiation of a single femtosecond laser pulse

    Energy Technology Data Exchange (ETDEWEB)

    Romashevskiy, S.A., E-mail: sa.romashevskiy@gmail.com [Joint Institute for High Temperatures of the Russian Academy of Sciences, Izhorskaya st. 13, Bd. 2, Moscow 125412 (Russian Federation); Ashitkov, S.I.; Ovchinnikov, A.V. [Joint Institute for High Temperatures of the Russian Academy of Sciences, Izhorskaya st. 13, Bd. 2, Moscow 125412 (Russian Federation); Kondratenko, P.S. [Nuclear Safety Institute of the Russian Academy of Sciences, Bol' shaya Tul' skaya st. 53, Moscow 115191 (Russian Federation); Moscow Institute of Physics and Technology, 9 Institutskiy per., Dolgoprudny, Moscow Region 141700 (Russian Federation); Agranat, M.B. [Joint Institute for High Temperatures of the Russian Academy of Sciences, Izhorskaya st. 13, Bd. 2, Moscow 125412 (Russian Federation)

    2016-06-30

    Graphical abstract: - Highlights: • Single pulse irradiation of silicon gave rise to the periodic mesoscale structures. • The number of the periodic structures depends on the incident laser fluence. • The theory of periodically modulated absorption of laser energy is proposed. - Abstract: The periodic mesoscale structures arranged in a circular symmetry were found at the silicon surface exposed to radiation of the single femtosecond laser pulse with a Gaussian intensity profile in the ambient air conditions. These peculiar structures have the appearance of the protrusions of ∼10 nm height and of ∼600 nm width (at a FWHM) separately located inside the ablated region with a period of the incident laser wavelength. It was found that their position at the surface corresponds to the specified laser intensity slightly above the ablation threshold. The number of the formed periodic structures varies with the fluence of the incident laser pulse and in our experiments it was found to have changed from one to eleven. We suppose that formation of these mesoscale structures is caused by heating of a microscale volume to the strongly defined temperature. The theoretical model was proposed to explain the obtained data. It assumes that the interference of incident laser radiation with laser-induced surface electromagnetic waves results in generation of periodic distribution of electron temperature. Thus formation of the periodic structures at the specified laser intensity is attributed to periodically modulated absorption of laser energy at a focal laser spot.

  14. Formats

    Directory of Open Access Journals (Sweden)

    Gehmann, Ulrich

    2012-03-01

    Full Text Available In the following, a new conceptual framework for investigating nowadays’ “technical” phenomena shall be introduced, that of formats. The thesis is that processes of formatting account for our recent conditions of life, and will do so in the very next future. It are processes whose foundations have been laid in modernity and which will further unfold for the time being. These processes are embedded in the format of the value chain, a circumstance making them resilient to change. In addition, they are resilient in themselves since forming interconnected systems of reciprocal causal circuits.Which leads to an overall situation that our entire “Lebenswelt” became formatted to an extent we don’t fully realize, even influencing our very percep-tion of it.

  15. Dynamics of the formation of laser-induced periodic surface structures (LIPSS) upon femtosecond two-color double-pulse irradiation of metals, semiconductors, and dielectrics

    Energy Technology Data Exchange (ETDEWEB)

    Höhm, S.; Herzlieb, M.; Rosenfeld, A. [Max-Born-Institut für Nichtlineare Optik und Kurzzeitspektroskopie (MBI), Max-Born-Straße 2A, D-12489 Berlin (Germany); Krüger, J. [BAM Bundesanstalt für Materialforschung und –prüfung, Unter den Eichen 87, D-12205 Berlin (Germany); Bonse, J., E-mail: joern.bonse@bam.de [BAM Bundesanstalt für Materialforschung und –prüfung, Unter den Eichen 87, D-12205 Berlin (Germany)

    2016-06-30

    Graphical abstract: - Highlights: • LIPSS formation on Fused Silica, Silicon, and Titanium is studied upon parallel and cross-polarized two-color (400 and 800 nm) double-fs-pulse irradiation. • LIPSS orientation on Fused Silica follows the polarization of the first pulse. • LIPSS formation on Silicon and Titanium can be explained by a plasmonic model. - Abstract: In order to address the dynamics and physical mechanisms of LIPSS formation for three different classes of materials (metals, semiconductors, and dielectrics), two-color double-fs-pulse experiments were performed on Titanium, Silicon and Fused Silica. For that purpose a Mach–Zehnder interferometer generated polarization controlled (parallel or cross-polarized) double-pulse sequences at 400 nm and 800 nm wavelength, with inter-pulse delays up to a few picoseconds. Multiple of these two-color double-pulse sequences were collinearly focused by a spherical mirror to the sample surfaces. The fluence of each individual pulse (400 nm and 800 nm) was always kept below its respective ablation threshold and only the joint action of both pulses lead to the formation of LIPSS. Their resulting characteristics (periods, areas) were analyzed by scanning electron microscopy. The periods along with the LIPSS orientation allow a clear identification of the pulse which dominates the energy coupling to the material. For strong absorbing materials (Silicon, Titanium), a wavelength-dependent plasmonic mechanism can explain the delay-dependence of the LIPSS. In contrast, for dielectrics (Fused Silica) the first pulse always dominates the energy deposition and LIPSS orientation, supporting a non-plasmonic formation scenario. For all materials, these two-color experiments confirm the importance of the ultrafast energy deposition stage for LIPSS formation.

  16. Orbit optimization and time delay interferometry for inclined ASTROD-GW formation with half-year precession-period

    CERN Document Server

    Wang, Gang

    2014-01-01

    ASTROD-GW (ASTROD [Astrodynamical Space Test of Relativity using Optical Devices] optimized for Gravitational Wave detection) is a gravitational-wave mission with the aim of detecting gravitational waves from massive black holes, extreme mass ratio inspirals (EMRIs) and galactic compact binaries, together with testing relativistic gravity and probing dark energy and cosmology. Mission orbits of the 3 spacecrafts forming a nearly equilateral triangular array are chosen to be near the Sun-Earth Lagrange points L3, L4 and L5. The 3 spacecrafts range interferometrically with one another with arm length about 260 million kilometers. For 260 times longer arm length, the detection sensitivity of ASTROD-GW is 260 fold better than that of eLISA/NGO in the lower frequency region by assuming the same acceleration noise. Therefore, ASTROD-GW will be a better cosmological probe. In previous papers, we have worked out the time delay interferometry (TDI) for the ecliptic formation. To resolve the reflection ambiguity about ...

  17. Formation of periodic microswelling structures on silicone rubber surface using ArF excimer laser to realize superhydrophobic property

    Science.gov (United States)

    Nojiri, Hidetoshi; Setyo Pambudi, Wisnu; Okoshi, Masayuki

    2017-07-01

    Periodic microswelling structures were photochemically induced on a silicone rubber surface using a 193 nm ArF excimer laser. Microspheres made of silica glass (SiO2) of 2.5 µm diameter were aligned on the silicone rubber surface during laser irradiation; the laser beam was focused on the silicone surface underneath each microsphere. The height and diameter of the formed microswelling structures were found to be controllable by changing the Ar gas flow rate, single-pulse laser fluence, and laser irradiation time. The chemical bonding of the laser-irradiated sample did not change and thus remained to be a silicone, as analyzed by X-ray photoelectron spectroscopy. As a result, microswelling structures of approximately 1.3 µm height and 1.3 µm diameter were successfully obtained. The contact angles of water on the microstructured silicone were measured to be 150° and larger, clearly indicating superhydrophobicity. The mechanism by which the microswellings form their shape was discussed on the basis of the changes in the focal point and spot size during laser irradiation through the SiO2 microsphere.

  18. Spontaneous formation of spiral-like patterns with distinct periodic physical properties by confined electrodeposition of Co-In disks

    Science.gov (United States)

    Golvano-Escobal, Irati; Gonzalez-Rosillo, Juan Carlos; Domingo, Neus; Illa, Xavi; López-Barberá, José Francisco; Fornell, Jordina; Solsona, Pau; Aballe, Lucia; Foerster, Michael; Suriñach, Santiago; Baró, Maria Dolors; Puig, Teresa; Pané, Salvador; Nogués, Josep; Pellicer, Eva; Sort, Jordi

    2016-01-01

    Spatio-temporal patterns are ubiquitous in different areas of materials science and biological systems. However, typically the motifs in these types of systems present a random distribution with many possible different structures. Herein, we demonstrate that controlled spatio-temporal patterns, with reproducible spiral-like shapes, can be obtained by electrodeposition of Co-In alloys inside a confined circular geometry (i.e., in disks that are commensurate with the typical size of the spatio-temporal features). These patterns are mainly of compositional nature, i.e., with virtually no topographic features. Interestingly, the local changes in composition lead to a periodic modulation of the physical (electric, magnetic and mechanical) properties. Namely, the Co-rich areas show higher saturation magnetization and electrical conductivity and are mechanically harder than the In-rich ones. Thus, this work reveals that confined electrodeposition of this binary system constitutes an effective procedure to attain template-free magnetic, electric and mechanical surface patterning with specific and reproducible shapes. PMID:27462025

  19. Heartbeat Stars: the Key to Unlocking the Formation and Circularization of Tight Binaries and Short Period Planets

    Science.gov (United States)

    Hambleton, Kelly

    Heartbeat stars are an emerging class of eccentric (e > 0.2) short-period ellipsoidal variables that undergo strong tidal interactions near orbital periastron. In the Kepler data we have identified 173 heartbeat stars, %20 of which pulsate with tidally excited modes: stellar oscillation modes that are excited to observable amplitudes (> 10 ppm) by the tidal forcing of the companion star. We have obtained 6 or more follow-up spectra for 31 Kepler heartbeat stars with tidally induced pulsations, most of which we obtained with the Keck telescope, Mauna Kea, and the 4-m Mayal telescope, Kitt Peak National Observatory. Using the combination of Kepler light curves and spectra (and distances from Gaia astrometry once available), we will produce binary star models for all the heartbeat stars in our sample by applying a combination of PHOEBE, a binary star modeling code; EMCEE, an afine invariant version of Markov chain Monte Carlo methods; and our own codes, which fit Doppler boosting and tidally induced pulsations. These models will provide accurate fundamental, orbital and pulsational parameters, which we will then use to pursue the two aims of this proposal. Our first aim is to determine orbital circularization rates due to tidally induced pulsations. It is predicted that the presence of tidally excited modes will cause an increase in the rate of orbital circularization. By analyzing the mode energies of the tidally excited modes using pulsation models (with the binary star parameters as inputs), we can determine the circularization rates of all the heartbeat stars in our sample. The results will provide key information on the link between tidally induced pulsations and orbital circularization, applicable to both binary stars and planets. Our second aim is to understand the impact of three body dynamics in forming tight binaries and short period planets. Approximately 96% of tight (P binaries have been observed to contain tertiary components. Heartbeat stars are

  20. ANALYSIS OF PERIODIC NANOSTRUCTURES FORMATION ON A GOLD SURFACE UNDER EXPOSURE TO ULTRASHORT LASER PULSES NEAR THE MELTING THRESHOLD

    Directory of Open Access Journals (Sweden)

    D. S. Ivanov

    2015-11-01

    Full Text Available Subject of Study. The mechanism of surface restructuring by ultrashort laser pulses involves a lot of fast, non-equilibrium, and interrelated processes while the solid is in a transient state. As a result, the analysis of the experimental data cannot cover all the mechanisms of nanostructuring. We present a direct comparison of a simulation and experimental results of surface nanomodification induced by a single laser pulse. Method. The experimental results were obtained by using a mask projection setup with a laser wavelength equal to 248 nm and a pulse length equal to 1.6 ps. This setup is used to produce an intensity grating on a gold surface with a sinusoidal shape and a period of 500 nm. The formed structures were analyzed by a scanning and transmission electron microscope, respectively. Then a hybrid atomistic-continuum model capable of capturing the essential mechanisms responsible for the nanostructuring process was used for modeling the interaction of the laser pulse with a thick gold target. Main Results. A good agreement between simulation and experimental data justifies the proposed approach as a powerful tool revealing the physics behind the nanostructuring process at a gold surface and providing a microscopic insight into the dynamics of the structuring processes of metals in general. The presented model, therefore, is an important step towards a new computational tool in predicting materials response to an ultrashort laser pulse on the atomic scale and properties of the modified surfaces. Practical Relevance. This detailed understanding of the dynamics of the process will pave the way towards pre-designed topologies for functionalized surfaces on the nano- and micro-scales.

  1. [The influence of increased clotting reactions as shown by thrombosis formation in the immediate postoperative period on aortic valve prothesis (author's transl)].

    Science.gov (United States)

    Harke, H; Schwarze, E W; Stambolis, C; Bernhard, A

    1975-08-01

    Massive thrombosis formation on the valve periphery and on the top surface of the valve occurred in three patients (1,5%) in the immediate postoperative period with the Björk-Shiley valve in the aortic position. Between the third and sixth day these patients died of acute heart failure as a result of coronary artery displacement. Upon autopsy operative technical complications and postoperative infections were ruled out as the cause of death. What appears to be clinically important is an increase in clotting time in the immediate postoperative period which can be proven statistically. This increased clotting inclination was only found in these three patients and in one patient with frequent immediate postoperative peripheral embolic episodes. We therefore feel that early anticoagulation therapy is necessary. Heparin administration is preferred as it not only lowers the clotting ability of the blood but also the adhesive quality of the platelets.

  2. Prolonged vortex formation during the ejection period in the left ventricle with low ejection fraction: a study by vector flow mapping.

    Science.gov (United States)

    Fukuda, Nobuaki; Itatani, Keiichi; Kimura, Koichi; Ebihara, Aya; Negishi, Kazuaki; Uno, Kansei; Miyaji, Kagami; Kurabayashi, Masahiko; Takenaka, Katsu

    2014-07-01

    Vortex formation in the left ventricle (LV) can be visualized by novel vector flow mapping (VFM) based on color Doppler and speckle tracking data. The aim of this study was to evaluate the impact of a vortex during the ejection period using VFM. Color Doppler images were obtained to produce VFM images in 80 subjects (20 normal, 29 with dilated cardiomyopathy, and 31 with old myocardial infarction). The duration of the LV vortex was measured and expressed as the ratio to the ejection time (VTRe). The VTRe showed significant correlations with EDV (ρ = 0.672, p vortex existed for only a limited time during the early ejection period. In contrast, the lower the EF was, the longer the vortex remained during systole. Evaluation of vortices by VFM may noninvasively provide novel insights into the pathophysiology of impaired cardiac function.

  3. The formation of risk groups for development of occupational diseases during the pre-employment and periodic medical examinations to conduct recreational activities

    Directory of Open Access Journals (Sweden)

    Bushmanov A. Yu.

    2014-12-01

    Full Text Available Research objective. The purpose ofthe study was to develop methodology for the formation of groups at risk of developing chronic diseases and complex of measures for their prevention when carrying out a compulsory medical examination of workers. Materials and methods. The results of periodic medical examinations for 2012 were analyzed according to 19 the final acts and reports 61 subjects ofthe Russian Federation. The results ofthe examination ofthe connection between disease and occupation were analyzed according to 50 examination protocols ofthe Burnasyan Federal Medical Biophysical Center of Federal Medical Biological Agency during 200-2010. Results. Based on the results ofthe conducted analysis methodology was developed to assess the risk of occupational disease fully meets the current legislative and regulatory framework of the Russian Federation and enable the individual and group level: to assess the risk of occupational diseases (high, medium, low, no; to identify possible nosological forms of diseases that should be expected, in accordance with the current list of occupational diseases; — to predict the presence or absence of responsibility employer for any case of occupational disease; to generate the necessary recommendations to the employer for the prevention of occupational diseases among workers. Conclusion. The method of formation of risk groups for development of occupational diseases recommended for medical organizations, conducting preliminary and periodic medical examinations.

  4. Is adolescence a period of identity formation for all youth? Insights from a four-wave longitudinal study of identity dynamics in Japan.

    Science.gov (United States)

    Hatano, Kai; Sugimura, Kazumi

    2017-11-01

    In the present study, we examined changes in identity dynamics during adolescence using the Dimensions of Identity Development Scale (DIDS), focusing on social and cultural factors possibly affecting identity formation. Identity formation among adolescents outside Western countries is largely unexplored; therefore, we focused on adolescents in Japan. We conducted a longitudinal study with 4 annual measurement points examining 968 Japanese adolescents (49.7% females). Two cohorts of participants were 13 and 16 years old at Time 1 and were followed until 16 and 19 years old, respectively. Latent class growth analysis extracted 3 identity trajectories corresponding to those found in previous research (i.e., achievement, troubled diffusion, and carefree diffusion) and 2 transitional trajectories newly identified in the present study (i.e., troubled diffusion-to-moratorium and moratorium-to-achievement). Adolescents following the achievement trajectory showed the best subjective well-being, whereas troubled diffused adolescents showed the worst. Furthermore, early-to-middle adolescents and urban adolescents tended to follow a low-commitment trajectory, whereas middle-to-late adolescents and rural adolescents tended to follow a high-commitment trajectory. These findings suggest that identity development proceeds toward integration during adolescence, but simultaneously, diverse developmental trajectories exist and incorporate contextual factors. Thus, in Japan, adolescence may be a period of identity formation for some adolescents, but not for others. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  5. Oceanic anoxic events of the Cretaceous period and their role in the formation of source rocks in the basins of continental margins

    Directory of Open Access Journals (Sweden)

    A.I. Konyukhov

    2017-09-01

    Full Text Available The Cretaceous period was marked not only by the dominance of warm climate, vast transgressions of the sea and widespread occurrence of carbonate deposits, but also by the formation of the richest petroleum formations, which are associated with the generation of a huge amount of hydrocarbons in the largest oil and gas basins of modern continental margins. Both early and late Cretaceous epochs were marked by several oceanic anoxic events (OAE of global and regional scale, accompanied by the accumulation of sediments enriched in organic matter, and by significant shifts in the ratios of stable isotopes C, O, and Sr. Various aspects of these events are considered in a huge number of articles published in recent years in major scientific publications. Unfortunately, their role in the formation of oil reservoirs has remained outside the scope of scientific analysis. Meanwhile Cretaceous OAE’s had led to the spreading of black shale and other sediments with high content of organic matter on the floor of Tethys ocean, central part of Atlantic and on the seamounts in the Pacific ocean. Among them only OAE 1a (Selli and OAE 2 (Bonarelli are known as more large anoxic events. The first occurred in the middle of Aptian time, the second near the Cenomanian-Turonian boundary (CTB. The analysis of the spreading of source rocks in the largest oil-and-gas bearing basins on the continental margins at that time – the Persian Gulf, Maracaibo, Middle and Upper Magdalena river, Putumayo and other basins – showed that episodes of OAE’s had not always found a reflection in the succession of major source rock’s formations. In the Persian Gulf a list of source rocks includes Hanifa, Garau, Gadvan, Kazhdumi, Ahmadi member and Gurpi formations of Cretaceous age. Thus it is certain that OAE’s were only separate parts of more complex history of accumulation of black shale and carbonate deposits with high content of total organic carbon on the continental margins

  6. The Role of Attitude to the Disease in Cardiac Patients Undergoing Vital Threat in the Formation of the Prediction of their Mental Adaptation to Post-hospital Period

    Directory of Open Access Journals (Sweden)

    Trifonova E.A.,

    2015-02-01

    Full Text Available The study was supported by the grant of the President of the Russian Federation MK-2076.2012.6. In the current study, the authors evaluated the role of relationship to disease in cardiac patients undergoing vital threat in the formation of the prediction of their mental adaptation in the distant post-hospital period. Longitudinal study (in-hospital and one year after discharge included two groups: patients with urgent cardiac status (N=47, 36 men, 11 women, age 34 to 66 years and patients with atrial arrhythmias, passing minimally invasive surgery (N=41, 22 men, 19 women, age 41 to 69 years. In-hospital stage used interviews and tests, questionnaires, and post-hospital stage was conducted using a telephone interview. We found that patients with a history of life-threatening cardiac condition, are less concerned about the disease than patients expecting to be relatively safe after minimally invasive surgery. In the forecast of the emotional status of patients, the severity of anxiety and disturbance of interpersonal relationships in the hospital period play an important role. Predictor of adherence to medical recommendations for men is a high disease concern, and in women – greater emotional stability.

  7. Synchronized collapse and formation of long-period stacking and chemical orders in Mg{sub 85}Zn{sub 6}Y{sub 9}

    Energy Technology Data Exchange (ETDEWEB)

    Matsushita, Masafumi, E-mail: matsushita@eng.ehime-u.ac.jp [Department of Mechanical Engineering, Ehime University, 3-Bunkyocho, Matsuyama 790-0826 (Japan); Bednarcik, Jozef [Deutsches Elektronen Synchrotron DESY, Notkestrasse 85, 22607 Hamburg (Germany); Sakata, Yuya; Akamatsu, Shutaro [Department of Mechanical Engineering, Ehime University, 3-Bunkyocho, Matsuyama 790-0826 (Japan); Nishiyama, Norimasa; Michalikova, Jana [Deutsches Elektronen Synchrotron DESY, Notkestrasse 85, 22607 Hamburg (Germany); Yamasaki, Michiaki; Kawamura, Yoshihito [Magnesium Research Center, Kumamoto University, 2-28-1 Kurokami, Kumamoto 860-8555 (Japan)

    2015-03-15

    Phase transformation of the long-period stacking order (LPSO) synchronized with the chemical concentration in Mg{sub 85}Zn{sub 6}Y{sub 9} has been investigated during both heating and cooling via in situ X-ray diffraction analysis. With increasing temperature, above 800 K, 10H-type LPSO phase collapsed firstly. 10H structural modulation collapsed earlier than the chemical modulation of 5 layers per period. The in-plane ordering consisted of aligned L1{sub 2}-type clusters vanished before the collapse of chemical and structural modulation of 18R-type LPSO. After, the chemical and structural modulation of 18R-type LPSO show synchronize collapse. During cooling, the 14H-type LPSO emerged in addition to the 18R-type LPSO. The growths of chemical and structural modulation start at the same temperature. After that, the formation of in-plane order consisting of aligned L1{sub 2}-type Zn–Y clusters emerged.

  8. [The influence of ecological factors on the formation of the parasite fauna of the common roach Rutilus rutilus Linnaeus (1758) in different periods of water abundance in Lake Sartlan (Southwestern Siberia)].

    Science.gov (United States)

    Sous', S M

    2011-01-01

    An analysis of the formation of the parasitofauna of the common roach under the influence of various biotic and abiotic environmental factors during three high water cycles observed in the last century is given. Periods of the formation of the enzooty are established.

  9. The formation of low-mass helium white dwarfs orbiting pulsars . Evolution of low-mass X-ray binaries below the bifurcation period

    Science.gov (United States)

    Istrate, A. G.; Tauris, T. M.; Langer, N.

    2014-11-01

    Context. Millisecond pulsars (MSPs) are generally believed to be old neutron stars (NSs) that have been spun up to high rotation rates via accretion of matter from a companion star in a low-mass X-ray binary (LMXB). This scenario has been strongly supported by various pieces of observational evidence. However, many details of this recycling scenario remain to be understood. Aims: Here we investigate binary evolution in close LMXBs to study the formation of radio MSPs with low-mass helium white dwarf companions (He WDs) in tight binaries with orbital periods Porb ≃ 2-9h. In particular, we examine i) if the observed systems can be reproduced by theoretical modelling using standard prescriptions of orbital angular momentum losses (i.e. with respect to the nature and the strength of magnetic braking), ii) if our computations of the Roche-lobe detachments can match the observed orbital periods, and iii) if the correlation between WD mass and orbital period (MWD, Porb) is valid for systems with Porb< 2 days. Methods: Numerical calculations with a detailed stellar evolution code were used to trace the mass-transfer phase in ~400 close LMXB systems with different initial values of donor star mass, NS mass, orbital period, and the so-called γ-index of magnetic braking. Subsequently, we followed the orbital and the interior evolution of the detached low-mass (proto) He WDs, including stages with residual shell hydrogen burning. Results: We find that severe fine-tuning is necessary to reproduce the observed MSPs in tight binaries with He WD companions of mass <0.20 M⊙, which suggests that something needs to be modified or is missing in the standard input physics of LMXB modelling. Results from previous independent studies support this conclusion. We demonstrate that the theoretically calculated (MWD, Porb)-relation is in general also valid for systems with Porb< 2 days, although with a large scatter in He WD masses between 0.15-0.20 M⊙. The results of the thermal

  10. Interstellar H adsorption and H₂ formation on the crystalline (010) forsterite surface: a B3LYP-D2* periodic study.

    Science.gov (United States)

    Navarro-Ruiz, Javier; Sodupe, Mariona; Ugliengo, Piero; Rimola, Albert

    2014-09-07

    The physisorption/chemisorption of atomic hydrogen on a slab model of the Mg2SiO4 forsterite (010) surface mimicking the interstellar dust particle surface has been modeled using a quantum mechanical approach based on periodic B3LYP-D2* density functional calculations (DFT) combined with flexible polarized Gaussian type basis sets, which allows a balanced description of the hydrogen/surface interactions for both minima and activated complexes. Physisorption of hydrogen is barrierless, very weak and occurs either close to surface oxygen atoms or on Mg surface ions. The contribution of dispersion interactions accounts for almost half of the adsorption energy. Both the hydrogen adsorption energy and barrier to hydrogen jump between equivalent surface sites are overestimated compared to experimental results meant to simulate the interstellar conditions in the laboratory. The hydrogen atom exclusively chemisorbs at the oxygen site of the forsterite (010) surface, forming a SiOH surface group and its spin density being entirely transferred to the neighboring Mg ion. Barrier for chemisorption allows rapid attachment of H at the surface at 100 K, but prevents the same process from occurring at 10 K. From this H-chemisorbed state, the second hydrogen chemisorption mainly occurs on the neighboring Mg ion, thus forming a Mg-H surface group, giving rise to a surface species stabilized by favorable electrostatic interactions between the OHH-Mg pair. The formation of molecular hydrogen at the (010) forsterite surface adopting a Langmuir-Hinshelwood mechanism takes place either starting from two physisorbed H atoms with an almost negligible kinetic barrier through a spin-spin coupling driven reaction or from two chemisorbed H atoms with a barrier surmountable even at T higher than 10 K. We also suggest that a nanosized model of the interstellar dust built from a replica of the forsterite unit cell is able to adsorb half the energy released by the H2 formation by increasing its

  11. Is Adolescence a Period of Identity Formation for All Youth? Insights from a Four-Wave Longitudinal Study of Identity Dynamics in Japan

    Science.gov (United States)

    Hatano, Kai; Sugimura, Kazumi

    2017-01-01

    In the present study, we examined changes in identity dynamics during adolescence using the Dimensions of Identity Development Scale (DIDS), focusing on social and cultural factors possibly affecting identity formation. Identity formation among adolescents outside Western countries is largely unexplored; therefore, we focused on adolescents in…

  12. Assessment of the anthropogenic component in the formation of extreme low-water periods based on remote sensing (case study for Russian south region)

    Science.gov (United States)

    Mikhailukova, Polina; Kireeva, Maria; Ilich, Vlad; Sazonov, Alexey; Kharlamov, Maxim

    2017-04-01

    Extreme low flow periods on the rivers are one of the most hydrological hazards. The aim of the study is determine causes of these periods based on the analysis of in land use changes. The territory of research is Don river basin. There is an assumption that the changes of Don watershed determines the increased duration of low-water periods, degradation of the river system of the region and the hard deficit of water resources. Authors analyzed archive of Landsat imagery for Don river basin for key time periods. The first key period is the middle 1970s - it was period of intensive land use on watershed. The second - is the middle 1990s characterized by decreasing rate of agriculture and increasing the area of abandoned lands. The third period is the middle 2000s when the rate of land use had started to increase. And the last period - 2014-2015 years, when low-water periods in Don river basin had become a disaster. We create mosaic of satellite images for each period and then classified it for several classes - urban area, different type of agricultural fields, forest, ponds and reservoirs. The analysis of classification results is demonstrate land use dynamic during last 45 years. The watershed changes was one the many reason of losses of the snowmelt runoff, which together with climate changes greatly increased the low-water period in the Don river basin. This research was supported by Russian President Grant 2017 (contract No. MK-2331.2017.5)

  13. Formations of hydroxyapatite and inositol hexakisphosphate in poultry litter during the composting period: sequential fractionation, P K-edge XANES and solution (31)P NMR investigations.

    Science.gov (United States)

    Hashimoto, Yohey; Takamoto, Akira; Kikkawa, Ren; Murakami, Keiichi; Yamaguchi, Noriko

    2014-05-20

    Little is known about how the solubility and chemical speciation of phosphorus (P) in poultry litters are altered during the composting period. This study investigated the quantitative and qualitative changes in organic P (Po) and inorganic P (Pi) compositions in poultry litters during the seven-day composting period using sequential extraction in combination with P K-edge X-ray absorption near-edge structure (XANES) and solution (31)P nuclear magnetic resonance (NMR) spectroscopy. The result of sequential extraction illustrated that the significant decrease of H2O-P by 55% in poultry litters occurred concomitantly with the increase of HCl-Pi and HCl-Po during the composting period (p poultry litter samples showed three distinct peaks indicative of hydroxyapatite. Phosphorus K-edge XANES confirmed the increase of hydroxyapatite during the composting period, corresponding to the increase of HCl-Pi determined by the sequential extraction. The NaOH-EDTA extraction for solution (31)P NMR revealed that myo-inositol hexakisphosphate (IHP) constituted about 80% of phosphate monoesters and was increased from 16 to 28% in the poultry litter during the composting period. The combined applications of chemical extraction and molecular-spectroscopic techniques determined that water-soluble P in poultry litter was transformed into less soluble phases, primarily hydroxyapatite and IHP, during the composting period.

  14. Setting the Periodic Table.

    Science.gov (United States)

    Saturnelli, Annette

    1985-01-01

    Examines problems resulting from different forms of the periodic table, indicating that New York State schools use a form reflecting the International Union of Pure and Applied Chemistry's 1984 recommendations. Other formats used and reasons for standardization are discussed. (DH)

  15. The Living Periodic Table

    Science.gov (United States)

    Nahlik, Mary Schrodt

    2005-01-01

    To help make the abstract world of chemistry more concrete eighth-grade students, the author has them create a living periodic table that can be displayed in the classroom or hallway. This display includes information about the elements arranged in the traditional periodic table format, but also includes visual real-world representations of the…

  16. Formation of Mobilization Model and Macroeconomic Dynamics of the USSR During the First Five-Year Period and the Great Patriotic War

    Directory of Open Access Journals (Sweden)

    Cheremisinov Georgiy Aleksandrovich

    2015-11-01

    Full Text Available The research of origin and functioning of mobilization model of economy is possible on the basis of the hypothesis about the government entrepreneurship as a typological sign of Russian economy development, the concept of threshold changes of macroeconomic dynamics, methodology of a chronotope and the theory of interrelation of the government organization of accumulation of the capital, industrialization, militarization, economic and territorial expansion of state power. Socio-economic reforming in our country was connected with threshold levels of impact of the government on economy that is confirmed by the analysis of macroeconomic conditions of emergence of the centralized planned management of a national economy. System transformations of the Russian economy to the revolutionary-military period (1914-1920 in the second half of the 1920s – early 1930s, in the period of the Great Patriotic War were carried out by the ruling power for the purpose of increase in quantity of the benefits, services, factors of production appropriated, distributed or used in its interests. The level of the centralized withdrawal of resources on irretrievable military expenses and on investments into industrialization of the power defined macroeconomic dynamics and extent of reorganization of a market mechanism of regulation of a domestic national economy. The mobilization model of directive planned management of a national economy created as a result of reforms of the beginning of the 1930s provided an economic basis of the USSR victory in the Great Patriotic War.

  17. A BACTERIA FORAGING ALGORITHM FOR SOLVING INTEGRATED MULTI-PERIOD CELL FORMATION AND SUBCONTRACTING PRODUCTION PLANNING IN A DYNAMIC CELLULAR MANUFACTURING SYSTEM

    Directory of Open Access Journals (Sweden)

    S.H. Tang

    2012-01-01

    Full Text Available

    ENGLISH ABSTRACT: The bacteria foraging algorithm (BFA is a new computation technique inspired by the social foraging behaviour of Escherichia coli (E. coli bacteria. Since the introduction of the BFA by Kevin M. Passino, there have been many challenges in employing this algorithm to problems other than those for which the algorithm was proposed. This research aims to apply this emerging optimisation algorithm to develop a mixed-integer programming model for designing cellular manufacturing systems (CMSs, and production planning in dynamic environments. In dynamic environments, product mix and part demand vary under multi-period planning horizons. Thus the best-designed cells for one period may not be adequate for subsequent periods, requiring their reconstruction. The advantages of the proposed model are as follows: consideration of batch inter-cell and intra-cell material handling by assuming the sequence of operations, allowing for alternative process plans for part types, and consideration of machine copying, with an emphasis on the effect of trade-offs between production and outsourcing costs. The goal is to minimise the sum of the machines’ constant and variable costs, inter-cell and intra-cell material handling costs, reconstruction costs, partial subcontracting costs, and inventory carrying costs. In addition, a newly-developed BFA-based optimisation algorithm has been compared with the branch and bound algorithm. The results suggest that the proposed algorithm performs better than related works.

    AFRIKAANSE OPSOMMING: Die ‘bacteria foraging algorithm’ (BFA is ‘n berekeningstegniek gebaseeer op die sosiale soekgedrag van Escherichia coli (E. coli bakterieë. Sedert die bekendstelling van BFA was daar talle uitdagings oor toepassings van die algoritme op ander probleme as dié waarvoor dit ontwikkel is. Dié navorsing poog om deur toepassing van die algoritme ‘n gemengde heelgetalprogrammeringmodel te ontwikkel vir die

  18. Enhanced oil recovery utilizing high-angle wells in the Frontier Formation, Badger Basin Field, Park County, Wyoming. Final report for the period October 1992--October 1993

    Energy Technology Data Exchange (ETDEWEB)

    Walker, J.P.; Fortmann, R.G.

    1994-12-01

    Badger Basin Field, discovered in 1931, produces at stripper rates from low-permeability fractured sandstones of the Upper Cretaceous Frontier Formation. Only 15% of the estimated 25 million barrels of oil originally in-place will be produced from the twenty-two attempted vertical completions. This project will increase recoverable reserves through a better understanding of the reservoir and factors which control production. Characterization of the reservoir has been accomplished through an integrated engineering, geological and geophysical approach. Production data, drilling and completion techniques, and relative location of wells on the anticline were reviewed and related to productivity. Literature was reviewed for interpretations on preferred flow directions on anticlinal structures. A structure map of the producing Frontier reservoir was constructed. Porosity development and its relationship to fracture networks was examined petrographically. Fractures in core were described and oriented using paleomagnetic techniques. Azimuths of fractures in outcrop were compared to fracture azimuths measured in the core. A 17 square-mile 3D seismic survey was designed, acquired and processed. Interpretation is being performed on a Sun workstation using Landmark Graphics software. Time-structure and amplitude-distribution maps will be constructed on three Frontier horizons. A location for a high-angle well will be chosen. The slant/horizontal test will be drilled and completed to increase recovery of reserves. Transfer of successful technologies will be accomplished by technical publications and presentations, and access to project materials, data, and field facilities.

  19. Kinematic GPS Analysis Gives New Insights on the Origin of the Very-Long-Period Seismic Signals at Miyake-Jima Volcano during the Caldera Formation

    Science.gov (United States)

    Munekane, H.; Oikawa, J.; Kobayashi, T.

    2014-12-01

    Miyake-jima is an active basaltic stratovolcano that is located 200km south of Tokyo, Japan. Its eruption event in 2000 was remarkable in that the large caldera was formed at the summit in approximately one month. During the caldera forming stage, very-long-period (VLP) seismic pulse waves with a duration of about 50-s that were accompanied by the step-like inflation were repeatedly recorded. Based on the broadband seismometer data, the piston model is proposed in which a vertical piston of solid materials in the conduit is intermittently sucked into the magma chamber located 3-5 km beneath the edific. In this study, we used the kinematic displacements from the continuous GPS observation to obtain additonal insights on the source mechanism of the pulse waves.  We calculated the kinematic displacements of 15 GPS stations on Miyake-jima that were in operation at that time at 30 sec interval. Then we extracted the displacements associated with each event using 20-hour time window centered at the occurrence of the event, and stacked the whole time series to obtain mean displacement time series. The obtained time series contain: 1) step-like displacements associated with the pulse waves, 2) exponential decay following the events with time constant of approximately half-day, and 3) steady linear displacements indicating continuous contraction of the edifice. The type one displacements can be attributed to the simultaneous inflation of an mogi-type spherical pressure source located at the depth of 3.6 km under the edifice, and the opening of the nearby vertical dike whose top is at the depth of 2.3 km. The type two displacements can be interpreted as the pressure adjustment at the type one source by the outflow of the magma driven by the pressure difference between the type one source and surrounding area. The type three displacements can be interpreted as the steady outflow of the magma from the type one source. The above results support the ``piston model'' for the

  20. LA ÉPOCA DE FORMACIÓN DE LA LENGUA DE PALENQUE: DATOS HISTÓRICOS Y LINGÜÍSTICOS THE FORMATION PERIOD OF THE PALENQUERO LANGUAGE: HISTORICAL AND LINGUISTIC DATA

    Directory of Open Access Journals (Sweden)

    Marianne Dieck

    2011-06-01

    Full Text Available El estudio de la formación y constitución de nuevas sociedades americanas nos enfrenta a la pregunta por el surgimiento del criollo palenquero. En los estudios realizados se ha propuesto el siglo XVII como el periodo probable de formación de esta lengua. El presente artículo aporta más argumentos a favor de esta hipótesis, argumentos basados en datos históricos publicados recientemente y en su interpretación a la luz de aquellas propuestas explicativas sobre la génesis de los criollos que tienen en cuenta el proceso de dilución del superestrato como punto de partida del surgimiento de nuevas lenguas. Los datos histórico-demográficos presentados apuntan a que el periodo de formación del criollo palenquero corresponde a la primera mitad del siglo XVII, una vez comenzado el proceso de dilución del español en la Provincia de Cartagena probablemente a fines del siglo XVI o comienzos del XVII, época en la que también se intensificó significativamente el cimarronaje.The study of the formation and consolidation of the new American societies necessarily leads to the question of the emergence of Palenquero Creole. Research has suggested the 17th century as the probable period of formation of this language. This study provides further arguments in favor of this hypothesis, arguments based on recently published historical information and on its interpretation in the light of explanatory proposals regarding the genesis of Creole languages that take into account the dilution of the superstrate as the starting point for the formation of new languages. The historical-demographic data provided point to the first half of the 17th century as the period of formation of Palenquero Creole, once the process of dilution of Spanish in the Province of Cartagena had begun, probably toward the end of the 16th century or early 17th century, a period during which maroon activity intensified significantly.

  1. Historiske perioder

    DEFF Research Database (Denmark)

    2017-01-01

    For at forstå fortiden og fortællingerne om den, må vi skabe en form for orden og systematik. Her spiller inddelingen af fortiden i historiske perioder en afgørende rolle – og historiske perioder er da også et kompetencemål efter 6. klasse. Videoen diskuterer forskellige principper...... for periodisering. Kronologi og sammenhænge hænger naturligt sammen med historiske perioder. Videoen handler også om forståelser og brug af synkrone og diakrone sammenhænge i faget....

  2. PERIODIC BEHAVIORS

    NARCIS (Netherlands)

    Napp, Diego; Put, Marius van der; Shankar, Shiva

    2010-01-01

    This paper studies behaviors that are defined on a torus, or equivalently, behaviors defined in spaces of periodic functions, and establishes their basic properties analogous to classical results of Malgrange, Palamodov, Oberst et al. for behaviors on R(n). These properties-in particular the

  3. Photolysis of Periodate and Periodic Acid in Aqueous Solution

    DEFF Research Database (Denmark)

    Sehested, Knud; Kläning, U. K.

    1978-01-01

    The photochemistry of periodate and periodic acid in aqueous solution was studied (i) by quantum yield measurements at low light intensity (ii) by flash photolysis, and (iii) by photolysis of glassy samples at 77 K. The photochemical studies were supplemented with pulse radiolysis studies...... of aqueous periodate solutions and with kinetic studies using stopped-flow technique. In strongly alkaline solution the photodecomposition of periodate proceeds via formation of O– and IVI. At pH

  4. Absent menstrual periods - primary

    Science.gov (United States)

    Primary amenorrhea; No periods - primary; Absent periods - primary; Absent menses - primary; Absence of periods - primary ... nutrition Tumors In many cases, the cause of primary amenorrhea is not known.

  5. Evolution of periodicity in periodical cicadas.

    Science.gov (United States)

    Ito, Hiromu; Kakishima, Satoshi; Uehara, Takashi; Morita, Satoru; Koyama, Takuya; Sota, Teiji; Cooley, John R; Yoshimura, Jin

    2015-09-14

    Periodical cicadas (Magicicada spp.) in the USA are famous for their unique prime-numbered life cycles of 13 and 17 years and their nearly perfectly synchronized mass emergences. Because almost all known species of cicada are non-periodical, periodicity is assumed to be a derived state. A leading hypothesis for the evolution of periodicity in Magicicada implicates the decline in average temperature during glacial periods. During the evolution of periodicity, the determinant of maturation in ancestral cicadas is hypothesized to have switched from size dependence to time (period) dependence. The selection for the prime-numbered cycles should have taken place only after the fixation of periodicity. Here, we build an individual-based model of cicadas under conditions of climatic cooling to explore the fixation of periodicity. In our model, under cold environments, extremely long juvenile stages lead to extremely low adult densities, limiting mating opportunities and favouring the evolution of synchronized emergence. Our results indicate that these changes, which were triggered by glacial cooling, could have led to the fixation of periodicity in the non-periodical ancestors.

  6. Neuroethology of ultrasonic hearing in nocturnal butterflies (Hedyloidea).

    Science.gov (United States)

    Yack, Jayne E; Kalko, Elisabeth K V; Surlykke, Annemarie

    2007-06-01

    Nocturnal Hedyloidea butterflies possess ultrasound-sensitive ears that mediate evasive flight maneuvers. Tympanal ear morphology, auditory physiology and behavioural responses to ultrasound are described for Macrosoma heliconiaria, and evidence for hearing is described for eight other hedylid species. The ear is formed by modifications of the cubital and subcostal veins at the forewing base, where the thin (1-3 microm), ovoid (520 x 220 microm) tympanal membrane occurs in a cavity. The ear is innervated by nerve IIN1c, with three chordotonal organs attaching to separate regions of the tympanal membrane. Extracellular recordings from IIN1c reveal sensory responses to ultrasonic (>20 kHz), but not low frequency (Hearing is broadly tuned to frequencies between 40 and 80 kHz, with best thresholds around 60 dB SPL. Free flying butterflies exposed to ultrasound exhibit a variety of evasive maneuvers, characterized by sudden and unpredictable changes in direction, increased velocity, and durations of approximately 500 ms. Hedylid hearing is compared to that of several other insects that have independently evolved ears for the same purpose-bat detection. Hedylid hearing may also represent an interesting example of evolutionary divergence, since we demonstrate that the ears are homologous to low frequency ears in some diurnal Nymphalidae butterflies.

  7. Linking neuroethology to the chemical biology of natural products

    DEFF Research Database (Denmark)

    Olivera, Baldomero M.; Raghuraman, Shrinivasan; Schmidt, Eric W.

    2017-01-01

    From a biological perspective, a natural product can be defined as a compound evolved by an organism for chemical interactions with another organism including prey, predator, competitor, pathogen, symbiont or host. Natural products hold tremendous potential as drug leads and have been extensively...

  8. Neuroethology of ultrasonic hearing in nocturnal butterflies (Hedyloidea)

    DEFF Research Database (Denmark)

    Yack, Jayne E.; Kalko, Elisabeth K.V.; Surlykke, Annemarie

    2007-01-01

    Nocturnal Hedyloidea butterflies possess ultrasound-sensitive ears that mediate evasive flight maneuvers. Tympanal ear morphology, auditory physiology and behavioural responses to ultrasound are described for Macrosoma heliconiaria, and evidence for hearing is described for eight other hedylid....... Extracellular recordings from IIN1c reveal sensory responses to ultrasonic (>20 kHz), but not low frequency(butterflies exposed to ultrasound exhibit a variety of evasive maneuvers...... of evolutionary divergence, since we demonstrate that the ears are homologous to low frequency ears in some diurnal Nymphalidae butterflies....

  9. Stellar formation

    CERN Document Server

    Reddish, V C

    1978-01-01

    Stellar Formation brings together knowledge about the formation of stars. In seeking to determine the conditions necessary for star formation, this book examines questions such as how, where, and why stars form, and at what rate and with what properties. This text also considers whether the formation of a star is an accident or an integral part of the physical properties of matter. This book consists of 13 chapters divided into two sections and begins with an overview of theories that explain star formation as well as the state of knowledge of star formation in comparison to stellar structure

  10. Periodicity, the Canon and Sport

    Directory of Open Access Journals (Sweden)

    Thomas F. Scanlon

    2015-10-01

    Full Text Available The topic according to this title is admittedly a broad one, embracing two very general concepts of time and of the cultural valuation of artistic products. Both phenomena are, in the present view, largely constructed by their contemporary cultures, and given authority to a great extent from the prestige of the past. The antiquity of tradition brings with it a certain cachet. Even though there may be peripheral debates in any given society which question the specifics of periodization or canonicity, individuals generally accept the consensus designation of a sequence of historical periods and they accept a list of highly valued artistic works as canonical or authoritative. We will first examine some of the processes of periodization and of canon-formation, after which we will discuss some specific examples of how these processes have worked in the sport of two ancient cultures, namely Greece and Mesoamerica.

  11. Soil formation.

    NARCIS (Netherlands)

    Breemen, van N.; Buurman, P.

    1998-01-01

    Soil Formation deals with qualitative and quantitative aspects of soil formation (or pedogenesis) and the underlying chemical, biological, and physical processes. The starting point of the text is the process - and not soil classification. Effects of weathering and new formation of minerals,

  12. Shock dynamics in layered periodic media

    KAUST Repository

    Ketcheson, David I.

    2012-01-01

    Solutions of constant-coeffcient nonlinear hyperbolic PDEs generically develop shocks, even if the initial data is smooth. Solutions of hyperbolic PDEs with variable coeffcients can behave very differently. We investigate formation and stability of shock waves in a one-dimensional periodic layered medium by a computational study of time-reversibility and entropy evolution. We find that periodic layered media tend to inhibit shock formation. For small initial conditions and large impedance variation, no shock formation is detected even after times much greater than the time of shock formation in a homogeneous medium. Furthermore, weak shocks are observed to be dynamically unstable in the sense that they do not lead to significant long-term entropy decay. We propose a characteristic condition for admissibility of shocks in heterogeneous media that generalizes the classical Lax entropy condition and accurately predicts the formation or absence of shocks in these media.

  13. Visual quasi-periodicity

    NARCIS (Netherlands)

    Pogalin, E.; Smeulders, A.W.M.; Thean, A.H.C.

    2008-01-01

    Periodicity is at the core of the recognition of many actions. This paper takes the following steps to detect and measure periodicity. 1) We establish a conceptual framework of classifying periodicity in 10 essential cases, the most important of which are flashing (of a traffic light), pulsing (of

  14. Women in Journalism Education: The Formative Period, 1908-1930.

    Science.gov (United States)

    Beasley, Maurine H.

    Adopting the viewpoint of the women students involved, this paper examines the first two decades of academic journalism (1908-1930). Pointing out that women students were a sizeable element in journalism schools from their beginning in 1908, the paper calls attention to the fact that women and men students were prepared for quite different lives,…

  15. Second Period Access Report

    DEFF Research Database (Denmark)

    Maisondieu, Christophe; Giebhardt, Jochen; Tetu, Amelie

    The work described in this publication has received support from the European Community - Research Infrastructure Action under the FP7 “Capacities” Specific Programme through grant agreement number 262552, MaRINET. Project Periodic Report. 2nd Period: October 2012 – March 2014 inclusive.......The work described in this publication has received support from the European Community - Research Infrastructure Action under the FP7 “Capacities” Specific Programme through grant agreement number 262552, MaRINET. Project Periodic Report. 2nd Period: October 2012 – March 2014 inclusive....

  16. Painful menstrual periods

    Science.gov (United States)

    Menstruation - painful; Dysmenorrhea; Periods - painful; Cramps - menstrual; Menstrual cramps ... a few days during each menstrual cycle. Painful menstruation is the leading cause of lost time from ...

  17. On some periodicity effects

    DEFF Research Database (Denmark)

    Sorokin, Sergey V.

    2015-01-01

    The talk is concerned with the modelling of wave propagation in and vibration of periodic elastic structures. Although analysis of wave-guide properties of infinite periodic structures is a well establish research subject, some issues have not yet been fully addressed in the literature. The aim...... of the talk is to illustrate these issues in simple examples and to discuss possible applications and generalisations. First, the eigenfrequency spectra of finite periodic structures are compared with the location of stop-bands for their infinite counterparts for a hierarchy of four mathematical models....... In each case, special attention is paid to eigenfrequencies and eigenmodes of a single periodicity cell with appropriate boundary conditions. The influence of the amount of periodicity cells in a finite compound structure on its eigenfrequency spectrum is analyzed. Several features common...

  18. Periods and Nori motives

    CERN Document Server

    Huber, Annette

    2017-01-01

    This book casts the theory of periods of algebraic varieties in the natural setting of Madhav Nori’s abelian category of mixed motives. It develops Nori’s approach to mixed motives from scratch, thereby filling an important gap in the literature, and then explains the connection of mixed motives to periods, including a detailed account of the theory of period numbers in the sense of Kontsevich-Zagier and their structural properties. Period numbers are central to number theory and algebraic geometry, and also play an important role in other fields such as mathematical physics. There are long-standing conjectures about their transcendence properties, best understood in the language of cohomology of algebraic varieties or, more generally, motives. Readers of this book will discover that Nori’s unconditional construction of an abelian category of motives (over fields embeddable into the complex numbers) is particularly well suited for this purpose. Notably, Kontsevich's formal period algebra represents a to...

  19. Microevolution of human archaic groups of Arica, northern Chile, and its genetic contribution to populations from the Formative Period Microevolución de grupos humanos arcaicos de Arica, norte de Chile, y su contribución genética a las poblaciones del Período Formativo

    Directory of Open Access Journals (Sweden)

    HÉCTOR HUGO VARELA

    2006-06-01

    Full Text Available The microevolution of the archaic populations from Chile's northern coast and its morphological contribution to Formative period groups was studied. The sample comprised 181 individuals belonging to two Archaic (Morro-Uhle and Morro 1-1/6 and one Formative (Playa Miller-7 [Plm-7] series of the coast and one sample from the Formative (Alto Ramírez exhumed at the Azapa Valley. A total of 29 metric variables of the cranium were analyzed. Biological variability was assessed using discriminant analysis and Mahalanobis' D² distance stadistic (MDS. Population structure was inferred using a method based on quantitative genetic theory that predicts a lineal relationship between average within-group phenotypic variance and group distance to the population centroid. The four samples studied proved to be different from a morphologic point of view. The greatest distance was observed between Plm-7 (coast Formative and Alto Ramirez (valley Formative, the least between Morro-Uhle and Morro 1-1/6, the remaining distances presenting intermediate values. Regarding the total population, the most divergent group was Alto Ramírez and the least divergent was Morro1-1/6. A gradual biologic change was observed between Archaic (Morro Uhle and Morro 1-1/6 and coastal Formative populations (Plm-7 pointing to a morphological (genetic contribution of Archaic fishermen to Formative population of Chile's northern coast, without excluding gene flow from other groups of the South Central Andean AreaEstudiamos la microevolución de las poblaciones arcaicas de la costa norte y sus contribuciones morfológicas al Período Formativo. La muestra comprendió 181 individuos pertenecientes a dos colecciones arcaicas de la costa (Morro-Uhle y Morro 1-1/6 y una al formativo (Alto Ramírez exhumada en el Valle de Azapa. Un total de 29 variables métricas del cráneo fueron analizadas. La variabilidad biológica fue determinada utilizando análisis discriminante y distancias de

  20. Mean-periodic functions

    Directory of Open Access Journals (Sweden)

    Carlos A. Berenstein

    1980-01-01

    Full Text Available We show that any mean-periodic function f can be represented in terms of exponential-polynomial solutions of the same convolution equation f satisfies, i.e., u∗f=0(μ∈E′(ℝn. This extends to n-variables the work of L. Schwartz on mean-periodicity and also extends L. Ehrenpreis' work on partial differential equations with constant coefficients to arbitrary convolutors. We also answer a number of open questions about mean-periodic functions of one variable. The basic ingredient is our work on interpolation by entire functions in one and several complex variables.

  1. Characterizing bursty star formation

    Science.gov (United States)

    Emami, Najmeh

    2018-01-01

    An ongoing area of research in galaxy evolution is the efficiency of star formation as a function of galaxy halo mass. At low mass, it is believed that supernova feedback can expel gas from the galaxy and shut down star formation. However, there are still significant uncertainties in how the momentum/energy of the supernova couple with the gas and the efficiency with which it drives winds. Particularly uncertain are the parameters of the resulting bursts of star formation —amplitudes, durations, and periods — with important implications for interpreting observations of dwarf galaxies. Some hydrodynamical simulations predict order of magnitude bursts (and quenching) on very short (indicators of dwarf galaxies (H-alpha and ultraviolet luminosities) that trace star formation on different time scales (~5 Myr and ~20 Myr, respectively), as well as their relation to the average galaxies of similar stellar mass, to better constrain the parameters of the star formation bursts. We find that the burst amplitude increases with decreasing stellar mass, with amplitudes ranging two orders of magnitude at stellar masses of 10^7. We also find that the star formation is quenched very rapidly, with e-folding times less than 10 Myr in galaxies with stellar masses less than 10^(7.5). We conclude by comparing our results to recent hydrodynamical simulations and discussing the effects of stochastic sampling of the stellar initial mass function.

  2. The Periodic Table CD.

    Science.gov (United States)

    Banks, Alton J.; Holmes, Jon L.

    1995-01-01

    Describes the characteristics of the digitized version of The Periodic Table Videodisc. Provides details about the organization of information and access to the data via Macintosh and Windows computers. (DDR)

  3. Galaxy Formation

    DEFF Research Database (Denmark)

    Sparre, Martin

    galaxies form stars throughout the history of the Universe, and secondly it is shown that observations of gamma-ray bursts (GRBs) can be used to probe galaxies with active star formation in the early Universe. A conclusion from the hydrodynamical simulations is that the galaxies from the stateof......Galaxy formation is an enormously complex discipline due to the many physical processes that play a role in shaping galaxies. The objective of this thesis is to study galaxy formation with two different approaches: First, numerical simulations are used to study the structure of dark matter and how...... is important, since it helps constraining chemical evolution models at high redshift. A new project studying how the population of galaxies hosting GRBs relate to other galaxy population is outlined in the conclusion of this thesis. The core of this project will be to quantify how the stellar mass function...

  4. Periodicity in magmatic systems

    Science.gov (United States)

    Caricchi, Luca

    2016-04-01

    Magmatic systems show periodicity in productivity, magma chemistry and dynamics of volcanic eruptions. The timescales over which such parameters change are highly variable and ranges between several tens of millions of years down to few hundredths of thousands years. While magmatic activity appears modulated at various frequencies, the lifetime of single volcanic systems, the duration of emplacement of single plutons, or the timespan over which a given volcanic region is active, appear to last for distinct but characteristic periods of time. Hundredths of thousands of years is a typical number for the range of zircon crystallisation ages in the products of large eruptions or for the lifetime of single plutons, while activity in volcanic regions or the duration of emplacement of crustal batholiths appears to last up to about 10 Ma. Several mechanisms such as variable magma productivity in the mantle, delamination, thermal and mechanical maturation of the crust have been proposed to modulate magmatic activity. All these processes indeed contribute to modulate the periodicity of magmatic activity, but because certain timescales are recurrent, some fundamental processes must play a fundamental role in regulating the "tempo" of magmatism. Are transitions of behaviour finally the product of major changes in mantle dynamics or is the crust the plays the pivotal role in modulating periodic variations observed in magmatic systems? In this contribution I will provide an overview of existing data on periodicity of magmatic systems and use thermal modelling to show that periodic variations of magma chemistry and the physical properties of magmas are an inexorable consequence of the evolution of the thermal budget of magmatic systems. I hope to trigger discussion and collaborations between experts of geodynamics and magmatism to establish relationships between periodicity, mantle and crustal processes.

  5. "Ictal" lateralized periodic discharges.

    Science.gov (United States)

    Sen-Gupta, Indranil; Schuele, Stephan U; Macken, Micheal P; Kwasny, Mary J; Gerard, Elizabeth E

    2014-07-01

    Whether lateralized periodic discharges (LPDs) represent ictal or interictal phenomena, and even the circumstances in which they may represent one or the other, remains highly controversial. Lateralized periodic discharges are, however, widely accepted as being ictal when they are time-locked to clinically apparent symptoms. We sought to investigate the characteristics of "ictal" lateralized periodic discharges (ILPDs) defined by time-locked clinical symptoms in order to explore the utility of using this definition to dichotomize LPDs into "ictal" and "nonictal" categories. Our archive of all continuous EEG (cEEG) reports of adult inpatients undergoing prolonged EEG monitoring for nonelective indications between 2007 and 2011 was searched to identify all reports describing LPDs. Lateralized periodic discharges were considered ILPDs when they were reported as being consistently time-locked to clinical symptoms; LPDs lacking a clear time-locked correlate were considered to be "nonictal" lateralized periodic discharges (NILPDs). Patient charts and available neuroimaging studies were also reviewed. Neurophysiologic localization of LPDs, imaging findings, presence of seizures, discharge outcomes, and other demographic factors were compared between patients with ILPDs and those with NILPDs. p-Values were adjusted for false discovery rate (FDR). One thousand four hundred fifty-two patients underwent cEEG monitoring at our institution between 2007 and 2011. Lateralized periodic discharges were reported in 90 patients, 10 of whom met criteria for ILPDs. Nine of the patients with ILPDs demonstrated motor symptoms, and the remaining patient experienced stereotyped sensory symptoms. Ictal lateralized periodic discharges had significantly increased odds for involving central head regions (odds ratio [OR]=11; 95% confidence interval [CI]=2.16-62.6; p=0.018, FDR adjusted), with a trend towards higher proportion of lesions involving the primary sensorimotor cortex (p=0.09, FDR

  6. Periodic Table of Students.

    Science.gov (United States)

    Johnson, Mike

    1998-01-01

    Presents an exercise in which an eighth-grade science teacher decorated the classroom with a periodic table of students. Student photographs were arranged according to similarities into vertical columns. Students were each assigned an atomic number according to their placement in the table. The table is then used to teach students about…

  7. Hereditary periodic fever syndromes

    NARCIS (Netherlands)

    McDermott, MF; Frenkel, J

    Hereditary periodic fever syndromes are defined by recurrent attacks of generalised inflammation for which no infectious or auto-immune cause can be identified. For most of these disorders, the molecular basis has recently been elucidated. This has opened the prospect of novel therapeutic

  8. Sawtooth Period Scaling

    CERN Document Server

    Connor, J W; Hastie, R J; Zocco, A

    2012-01-01

    We discuss the role of neoclassical resistivity and local magnetic shear in the prediction of the sawtooth period in tokamaks. When collisional detrapping of electrons is considered the value of the safety factor on axis, $q(t,0)$, evolves on a new time scale, $\\tau_{*}=\\tau_{\\eta}\

  9. Complications and mortality following stoma formation.

    OpenAIRE

    Harris, D. A.; Egbeare, D.; Jones, S.; Benjamin, H.; Woodward, A; Foster, M E

    2005-01-01

    INTRODUCTION: As stoma formation is thought to be declining, we performed a study to evaluate the rate of stoma formation and the impact on stoma complication rates, together with risk factors for complications. PATIENTS AND METHODS: Stoma incidence, individual complications and mortality rates were retrieved from a stoma nurse database of 345 stomas created over an 8-year period. RESULTS: Stoma formation increased over the study period, although the incidence of complications declined. Stoma...

  10. Digtets formater

    DEFF Research Database (Denmark)

    Schmidt, Michael Kallesøe; Rasmussen, Krista Stinne Greve; Skriver, Svend

    2017-01-01

    Løppenthin, Olga Ravn, Mikkel Thykier, Caspar Eric, and Simon Grotrian are discussed. By using the format as a point of departure rather than applying a more conventional practice of close reading, the authors argue for a broad-spectred approach to literary analysis which focuses on aspects of the conception......The article examines how key terminology of textual criticism can be taken as a starting point for the investigation of material aspects of contemporary poetry. The concepts in question are ‘text’ and ‘work’ as defined by Johnny Kondrup (2013). The authors take the view that the categorical...

  11. Cement Formation

    DEFF Research Database (Denmark)

    Telschow, Samira; Jappe Frandsen, Flemming; Theisen, Kirsten

    2012-01-01

    Cement production has been subject to several technological changes, each of which requires detailed knowledge about the high multiplicity of processes, especially the high temperature process involved in the rotary kiln. This article gives an introduction to the topic of cement, including...... an overview of cement production, selected cement properties, and clinker phase relations. An extended summary of laboratory-scale investigations on clinkerization reactions, the most important reactions in cement production, is provided. Clinker formations by solid state reactions, solid−liquid and liquid...

  12. Periodic Mesoporous Organosilica Nanorice

    Directory of Open Access Journals (Sweden)

    Mohanty Paritosh

    2008-01-01

    Full Text Available Abstract A periodic mesoporous organosilica (PMO with nanorice morphology was successfully synthesized by a template assisted sol–gel method using a chain-type precursor. The PMO is composed of D and T sites in the ratio 1:2. The obtained mesoporous nanorice has a surface area of 753 m2 g−1, one-dimensional channels, and a narrow pore size distribution centered at 4.3 nm. The nanorice particles have a length of ca. 600 nm and width of ca. 200 nm.

  13. The postanesthetic period. Complications.

    Science.gov (United States)

    Malamed, S F

    1987-01-01

    Postanesthetic complications can occur even in the best of circumstances. Proper preparation of the staff, aggressive monitoring of the recovering patient, and early recognition and management of the complications are essential if the outcome is to be successful. In reviewing postanesthetic complications, two factors are present in the overwhelming majority of situations--hypoxia and hypercarbia--often the direct result of inadequate monitoring during the postanesthetic period. The anesthetic procedure is not over once the anesthetic agents are discontinued. The skillful anesthetist is aware of the possibilities of postoperative complications and prevents problems by employing enhanced monitoring techniques during the recovery phase.

  14. Periods of Hecke characters

    CERN Document Server

    Schappacher, Norbert

    1988-01-01

    The starting point of this Lecture Notes volume is Deligne's theorem about absolute Hodge cycles on abelian varieties. Its applications to the theory of motives with complex multiplication are systematically reviewed. In particular, algebraic relations between values of the gamma function, the so-called formula of Chowla and Selberg and its generalization and Shimura's monomial relations among periods of CM abelian varieties are all presented in a unified way, namely as the analytic reflections of arithmetic identities beetween Hecke characters, with gamma values corresponding to Jacobi sums. The last chapter contains a special case in which Deligne's theorem does not apply.

  15. [An evaluation of the 1906 issues of the first medical periodical in Izmir, Hifzissihha Periodical].

    Science.gov (United States)

    Karayaman, Mehmet

    The purpose of this study is to review the first issues of Hifzissihha Periodical published in 1906 as the first medical periodical of Izmir. We already conducted a similar study on the 1908 issues of the same periodical published as 26 issues between May 8, 1908 and December 24, 1908. This particular study, on the other hand, mainly focuses on the very first issues (from Issue 3 to 21) which were published in 1906. Published as a weekly periodical in Turkish in Arabic alphabet by Doktor Taslizade Edhem Bey, the periodical was formatted in two columns with a 25.5 x 18.5 page size. The articles in the periodical included information about epidemics, mother and child health, healthy nutrition and maintaining a healthy life were written in a plain language. Our study also aims to provide information about the articles, authors, and the date and place of publication of each issue.

  16. Programmable Periodicity of Quantum Dot Arrays with DNA Origami Nanotubes

    OpenAIRE

    Bui, Hieu; Onodera, Craig; Kidwell, Carson; Tan, Yerpeng; Graugnard, Elton; Kuang, Wan; Lee, Jeunghoon; Knowlton, William B.; Yurke, Bernard; Hughes, William L.

    2010-01-01

    To fabricate quantum dot arrays with programmable periodicity, functionalized DNA origami nanotubes were developed. Selected DNA staple strands were biotin-labeled to form periodic binding sites for streptavidin-conjugated quantum dots. Successful formation of arrays with periods of 43 and 71 nm demonstrates precise, programmable, large-scale nanoparticle patterning; however, limitations in array periodicity were also observed. Statistical analysis of AFM images revealed evidence for steric h...

  17. Galaxy Formation

    CERN Document Server

    Longair, Malcolm S

    2008-01-01

    This second edition of Galaxy Formation is an up-to-date text on astrophysical cosmology, expounding the structure of the classical cosmological models from a contemporary viewpoint. This forms the background to a detailed study of the origin of structure and galaxies in the Universe. The derivations of many of the most important results are derived by simple physical arguments which illuminate the results of more advanced treatments. A very wide range of observational data is brought to bear upon these problems, including the most recent results from WMAP, the Hubble Space Telescope, galaxy surveys like the Sloan Digital Sky Survey and the 2dF Galaxy Redshift Survey, studies of Type 1a supernovae, and many other observations.

  18. Habit formation.

    Science.gov (United States)

    Smith, Kyle S; Graybiel, Ann M

    2016-03-01

    Habits, both good ones and bad ones, are pervasive in animal behavior. Important frameworks have been developed to understand habits through psychological and neurobiological studies. This work has given us a rich understanding of brain networks that promote habits, and has also helped us to understand what constitutes a habitual behavior as opposed to a behavior that is more flexible and prospective. Mounting evidence from studies using neural recording methods suggests that habit formation is not a simple process. We review this evidence and take the position that habits could be sculpted from multiple dissociable changes in neural activity. These changes occur across multiple brain regions and even within single brain regions. This strategy of classifying components of a habit based on different brain signals provides a potentially useful new way to conceive of disorders that involve overly fixed behaviors as arising from different potential dysfunctions within the brain's habit network.

  19. [Childhood periodic syndromes].

    Science.gov (United States)

    Cuvellier, J-C; Lépine, A

    2010-01-01

    This review focuses on the so-called "periodic syndromes of childhood that are precursors to migraine", as included in the Second Edition of the International Classification of Headache Disorders. Three periodic syndromes of childhood are included in the Second Edition of the International Classification of Headache Disorders: abdominal migraine, cyclic vomiting syndrome and benign paroxysmal vertigo, and a fourth, benign paroxysmal torticollis is presented in the Appendix. The key clinical features of this group of disorders are the episodic pattern and intervals of complete health. Episodes of benign paroxysmal torticollis begin between 2 and 8 months of age. Attacks are characterized by an abnormal inclination and/or rotation of the head to one side, due to cervical dystonia. They usually resolve by 5 years. Benign paroxysmal vertigo presents as sudden attacks of vertigo, accompanied by inability to stand without support, and lasting seconds to minutes. Age at onset is between 2 and 4 years, and the symptoms disappear by the age of 5. Cyclic vomiting syndrome is characterized in young infants and children by repeated stereotyped episodes of pernicious vomiting, at times to the point of dehydration, and impacting quality of life. Mean age of onset is 5 years. Abdominal migraine remains a controversial issue and presents in childhood with repeated stereotyped episodes of unexplained abdominal pain, nausea and vomiting occurring in the absence of headache. Mean age of onset is 7 years. Both cyclic vomiting syndrome and abdominal migraine are noted for the absence of pathognomonic clinical features but also for the large number of other conditions to be considered in their differential diagnoses. Diagnostic criteria, such as those of the Second Edition of the International Classification of Headache Disorders and the North American Society for Pediatric Gastroenterology, Hepatology and Nutrition, have made diagnostic approach and management easier. Their diagnosis

  20. Fracture Fluid Additive and Formation Degradations

    Science.gov (United States)

    This presentation is on reactions that describe the degradation of fracturing fluids & formations during the hydraulic fracturing process & the clean‐up period. It contains a description of primary chemical reaction controls, & common degradation reactions

  1. Curriculum Formation: A Case Study from History

    Science.gov (United States)

    Shay, Suellen

    2011-01-01

    Drawing on the work of Bernstein and Maton and using a case-study approach, this study explores the formation of an undergraduate history curriculum at the University of Cape Town. This article focuses on two periods of curriculum formation referred to as history as canon and history as social science. With respect to these two curriculum periods…

  2. Periodic feedback stabilization for linear periodic evolution equations

    CERN Document Server

    Wang, Gengsheng

    2016-01-01

    This book introduces a number of recent advances regarding periodic feedback stabilization for linear and time periodic evolution equations. First, it presents selected connections between linear quadratic optimal control theory and feedback stabilization theory for linear periodic evolution equations. Secondly, it identifies several criteria for the periodic feedback stabilization from the perspective of geometry, algebra and analyses respectively. Next, it describes several ways to design periodic feedback laws. Lastly, the book introduces readers to key methods for designing the control machines. Given its coverage and scope, it offers a helpful guide for graduate students and researchers in the areas of control theory and applied mathematics.

  3. 76 FR 80312 - Periodic Reporting

    Science.gov (United States)

    2011-12-23

    ... Distribution Center (ADC) automation flats in First-Class Mail, Periodicals, and Standard Mail. Id. at 9-10... model for Periodicals flats. Currently, cells for the coverage of mechanized ADC pallet bundle sortation...

  4. 76 FR 8325 - Periodic Reporting

    Science.gov (United States)

    2011-02-14

    ... data for Presort First-Class Mail, and End-to-End Periodicals. Request at 1. The Request includes... Standard Mail, Outside County Periodicals, non-retail Media Mail, Library Mail, Bound Printed Matter...

  5. The redoubtable ecological periodic table

    Science.gov (United States)

    Ecological periodic tables are repositories of reliable information on quantitative, predictably recurring (periodic) habitat–community patterns and their uncertainty, scaling and transferability. Their reliability derives from their grounding in sound ecological principle...

  6. Nonparametric Inference for Periodic Sequences

    KAUST Repository

    Sun, Ying

    2012-02-01

    This article proposes a nonparametric method for estimating the period and values of a periodic sequence when the data are evenly spaced in time. The period is estimated by a "leave-out-one-cycle" version of cross-validation (CV) and complements the periodogram, a widely used tool for period estimation. The CV method is computationally simple and implicitly penalizes multiples of the smallest period, leading to a "virtually" consistent estimator of integer periods. This estimator is investigated both theoretically and by simulation.We also propose a nonparametric test of the null hypothesis that the data have constantmean against the alternative that the sequence of means is periodic. Finally, our methodology is demonstrated on three well-known time series: the sunspots and lynx trapping data, and the El Niño series of sea surface temperatures. © 2012 American Statistical Association and the American Society for Quality.

  7. Periodicity of DNA in exons

    Directory of Open Access Journals (Sweden)

    Kinghorn Brian

    2004-08-01

    Full Text Available Abstract Background The periodic pattern of DNA in exons is a known phenomenon. It was suggested that one of the initial causes of periodicity could be the universal (RNYnpattern (R = A or G, Y = C or U, N = any base of ancient RNA. Two major questions were addressed in this paper. Firstly, the cause of DNA periodicity, which was investigated by comparisons between real and simulated coding sequences. Secondly, quantification of DNA periodicity was made using an evolutionary algorithm, which was not previously used for such purposes. Results We have shown that simulated coding sequences, which were composed using codon usage frequencies only, demonstrate DNA periodicity very similar to the observed in real exons. It was also found that DNA periodicity disappears in the simulated sequences, when the frequencies of codons become equal. Frequencies of the nucleotides (and the dinucleotide AG at each location along phase 0 exons were calculated for C. elegans, D. melanogaster and H. sapiens. Two models were used to fit these data, with the key objective of describing periodicity. Both of the models showed that the best-fit curves closely matched the actual data points. The first dynamic period determination model consistently generated a value, which was very close to the period equal to 3 nucleotides. The second fixed period model, as expected, kept the period exactly equal to 3 and did not detract from its goodness of fit. Conclusions Conclusion can be drawn that DNA periodicity in exons is determined by codon usage frequencies. It is essential to differentiate between DNA periodicity itself, and the length of the period equal to 3. Periodicity itself is a result of certain combinations of codons with different frequencies typical for a species. The length of period equal to 3, instead, is caused by the triplet nature of genetic code. The models and evolutionary algorithm used for characterising DNA periodicity are proven to be an effective tool

  8. Multi-Periodicity Induces Prominent Optical Phenomena in Plasmonic Multilayers

    DEFF Research Database (Denmark)

    Orlov, Alexey A.; Krylova, A. K.; Zhukovsky, Sergei

    2014-01-01

    We introduce multi-periodicity in plasmonic multilayers and develop a general theory for the description of their eigenwaves. We define the order of multi-periodicity as the number of different kinds of plasmonic interfaces present in the multilayer, and investigate the optical effects that arise...... as this order increases from one (simple periodic multilayers) to two (bi- periodic multilayers) and beyond. For example, we show the formation of additional photonic bands, multi-refringence of p -polarized light, Dirac and mixed states....

  9. Long period oscillations in sunspots

    Science.gov (United States)

    Chorley, N.; Hnat, B.; Nakariakov, V. M.; Inglis, A. R.; Bakunina, I. A.

    2010-04-01

    Long period oscillations of the gyroresonant emission from sunspot atmospheres are studied. Time series data generated from the sequences of images obtained by the Nobeyama Radioheliograph operating at a frequency of 17 GHz for three sunspots have been analysed and are found to contain significant periods in the range of several tens of minutes. Wavelet analysis shows that these periods are persistent throughout the observation periods. The presence of the oscillations is confirmed by several methods (periodogram, wavelets, Fisher randomisation and empirical mode decomposition). Spatial analysis using the techniques of period, power, correlation and time lag mapping reveals regions of enhanced oscillatory power in the umbral regions. Also seen are two regions of coherent oscillation of about 25 pixels in size, that oscillate in anti-phase with each other. Possible interpretation of the observed periodicities is discussed, in terms of the shallow sunspot model and the leakage of the solar g-modes.

  10. From Periodic Properties to a Periodic Table Arrangement

    Science.gov (United States)

    Besalú, Emili

    2013-01-01

    A periodic table is constructed from the consideration of periodic properties and the application of the principal components analysis technique. This procedure is useful for objects classification and data reduction and has been used in the field of chemistry for many applications, such as lanthanides, molecules, or conformers classification.…

  11. Applied periodization: a methodological approach

    OpenAIRE

    Naclerio, Fernando; Moody, Jeremy; Chapman, Mark

    2013-01-01

    Periodization represents an optimal modality for organizing training programs in athletes, recreational and rehabilitative practitioners. The selected procedure, however, should be based on the athlete’s age, level of performance, specific goals or competition characteristics. A common theme throughout all periodization paradigms is the requirement to manipulate the entire program variables (intensity, volume, frequency, recovery periods and exercise selection) in order to progress from gener...

  12. Assessing periodicity of periodic leg movements during sleep.

    Science.gov (United States)

    Rummel, Christian; Gast, Heidemarie; Schindler, Kaspar; Müller, Markus; Amor, Frédérique; Hess, Christian W; Mathis, Johannes

    2010-01-01

    Periodic leg movements (PLM) during sleep consist of involuntary periodic movements of the lower extremities. The debated functional relevance of PLM during sleep is based on correlation of clinical parameters with the PLM index (PLMI). However, periodicity in movements may not be reflected best by the PLMI. Here, an approach novel to the field of sleep research is used to reveal intrinsic periodicity in inter movement intervals (IMI) in patients with PLM. Three patient groups of 10 patients showing PLM with OSA (group 1), PLM without OSA or RLS (group 2) and PLM with RLS (group 3) are considered. Applying the "unfolding" procedure, a method developed in statistical physics, enhances or even reveals intrinsic periodicity of PLM. The degree of periodicity of PLM is assessed by fitting one-parameter distributions to the unfolded IMI distributions. Finally, it is investigated whether the shape of the IMI distributions allows to separate patients into different groups. Despite applying the unfolding procedure, periodicity is neither homogeneous within nor considerably different between the three clinically defined groups. Data-driven clustering reveals more homogeneous and better separated clusters. However, they consist of patients with heterogeneous demographic data and comorbidities, including RLS and OSA. The unfolding procedure may be necessary to enhance or reveal periodicity. Thus this method is proposed as a pre-processing step before analyzing PLM statistically. Data-driven clustering yields much more reasonable results when applied to the unfolded IMI distributions than to the original data. Despite this effort no correlation between the degree of periodicity and demographic data or comorbidities is found. However, there are indications that the nature of the periodicity might be determined by long-range interactions between LM of patients with PLM and OSA.

  13. Assessing periodicity of periodic leg movements during sleep

    Directory of Open Access Journals (Sweden)

    Christian eRummel

    2010-09-01

    Full Text Available Background: Periodic leg movements during sleep (PLMS consist of involuntary periodic movements of the lower extremities. The debated functional relevance of PLMS is based on correlation of clinical parameters with the PLMS index (PLMI. However, periodicity in movements may not be reflected best by the PLMI. Here, an approach novel to the field of sleep research is used to reveal intrinsic periodicity in inter movement intervals (IMI in patients with PLMS. Methods: Three patient groups of 10 patients showing PLMS with OSA (group 1, PLMS without OSA or RLS (group 2 and PLMS with RLS (group 3 were considered. Applying the ``unfolding'' procedure, a method developed in statistical physics, enhanced or even revealed intrinsic periodicity of PLMS. The degree of periodicity of PLMS was assessed by fitting one-parameter distributions to the unfolded IMI distributions. Finally, it was investigated whether the shape of the IMI distributions allows to separate patients into different groups. Results: Despite applying the unfolding procedure, periodicity was neither homogeneous within nor considerably different between the three clinically defined groups. Data-driven clustering revealed more homogeneous and better separated clusters. However, they consisted of patients with heterogeneous demographic data and comorbidities, including RLS {em and} OSA. Conclusions: The unfolding procedure may be necessary to enhance or reveal periodicity. Thus this method is proposed as a pre-processing step before analyzing PLMS statistically. Data-driven clustering yields much more reasonable results when applied to the unfolded IMI distributions than to the original data. Despite this effort no correlation between the {em degree} of periodicity and demographic data or comorbidities was found. However, there were indications that the {em nature} of the periodicity might be determined by long-range interactions between LM of patients with PLMS and OSA.

  14. From the Mendeleev periodic table to particle physics and back to the periodic table

    Energy Technology Data Exchange (ETDEWEB)

    Kibler, Maurice R. [Universite de Lyon, Institut de Physique Nucleaire, Universite Lyon 1 and CNRS/IN2P3, 43 Bd du 11 Novembre 1918, F-69622 Villeurbanne Cedex (France)

    2006-11-15

    We briefly describe in this paper the passage from Mendeleev's chemistry (1869) to atomic physics (in the 1900's), nuclear physics (in the 1932's) and particle physics (from 1953 to 2006). We show how the consideration of symmetries, largely used in physics since the end of the 1920's, gave rise to a new format of the periodic table in the 1970's. More specifically, this paper is concerned with the application of the group SO(4,2)xSU(2) to the periodic table of chemical elements. It is shown how the Madelung rule of the atomic shell model can be used for setting up a periodic table that can be further rationalized via the group SO(4,2)xSU(2) and some of its subgroups. Qualitative results are obtained from this nonstandard table. (author)

  15. Quasi-periodicity in relative quasi-periodic tori

    Science.gov (United States)

    Fassò, Francesco; García-Naranjo, Luis C.; Giacobbe, Andrea

    2015-10-01

    At variance from the cases of relative equilibria and relative periodic orbits of dynamical systems with symmetry, the dynamics in relative quasi-periodic tori (namely, subsets of the phase space that project to an invariant torus of the reduced system on which the flow is quasi-periodic) is not yet completely understood. Even in the simplest situation of a free action of a compact and abelian connected group, the dynamics in a relative quasi-periodic torus is not necessarily quasi-periodic. It is known that quasi-periodicity of the unreduced dynamics is related to the reducibility of the reconstruction equation, and sufficient conditions for it are virtually known only in a perturbation context. We provide a different, though equivalent, approach to this subject, based on the hypothesis of the existence of commuting, group-invariant lifts of a set of generators of the reduced torus. Under this hypothesis, which is shown to be equivalent to the reducibility of the reconstruction equation, we give a complete description of the structure of the relative quasi-periodic torus, which is a principal torus bundle whose fibers are tori of a dimension which exceeds that of the reduced torus by at most the rank of the group. The construction can always be done in such a way that these tori have minimal dimension and carry ergodic flow.

  16. Detecting periodicities with Gaussian processes

    Directory of Open Access Journals (Sweden)

    Nicolas Durrande

    2016-04-01

    Full Text Available We consider the problem of detecting and quantifying the periodic component of a function given noise-corrupted observations of a limited number of input/output tuples. Our approach is based on Gaussian process regression, which provides a flexible non-parametric framework for modelling periodic data. We introduce a novel decomposition of the covariance function as the sum of periodic and aperiodic kernels. This decomposition allows for the creation of sub-models which capture the periodic nature of the signal and its complement. To quantify the periodicity of the signal, we derive a periodicity ratio which reflects the uncertainty in the fitted sub-models. Although the method can be applied to many kernels, we give a special emphasis to the Matérn family, from the expression of the reproducing kernel Hilbert space inner product to the implementation of the associated periodic kernels in a Gaussian process toolkit. The proposed method is illustrated by considering the detection of periodically expressed genes in the arabidopsis genome.

  17. Quasi Periodic Oscillations in Blazars

    Indian Academy of Sciences (India)

    2016-01-27

    Jan 27, 2016 ... Home; Journals; Journal of Astrophysics and Astronomy; Volume 35; Issue 3. Quasi Periodic Oscillations in Blazars ... Here we report our recent discoveries of Quasi-Periodic Oscillations (QPOs) in blazars time series data in X-ray and optical electromagnetic bands. Any such detection can give important ...

  18. A periodic pattern generator for dental diversity

    Directory of Open Access Journals (Sweden)

    Streelman J Todd

    2008-07-01

    Full Text Available Abstract Background Periodic patterning of iterative structures is a fundamental process during embryonic organization and development. Studies have shown how gene networks are employed to pattern butterfly eyespots, fly bristles and vertebrate epithelial appendages such as teeth, feathers, hair and mammary glands. Despite knowledge of how these features are organized, little is known about how diversity in periodic patterning is generated in nature. We address this problem through the molecular analysis of oral jaw dental diversity in Lake Malawi cichlids, where closely related species exhibit from 1 to 20 rows of teeth, with total teeth counts ranging from around 10 to 700. Results We investigate the expression of conserved gene networks (involving bmp2, bmp4, eda, edar, fgf8, pax9, pitx2, runx2, shh and wnt7b known to pattern iterative structures and teeth in other vertebrates. We show that spatiotemporal variation in expression pattern reflects adult morphological diversity among three closely related Malawi cichlid species. Combinatorial epithelial expression of pitx2 and shh appears to govern the competence both of initial tooth sites and future tooth rows. Epithelial wnt7b and mesenchymal eda are expressed in the inter-germ and inter-row regions, and likely regulate the spacing of these shh-positive units. Finally, we used chemical knockdown to demonstrate the fundamental role of hedgehog signalling and initial placode formation in the organization of the periodically patterned cichlid dental programme. Conclusion Coordinated patterns of gene expression differ among Malawi species and prefigure the future-ordered distribution of functional teeth of specific size and spacing. This variation in gene expression among species occurs early in the developmental programme for dental patterning. These data show how a complex multi-rowed vertebrate dentition is organized and how developmental tinkering of conserved gene networks during iterative

  19. Long-period clocks from short-period oscillators

    Science.gov (United States)

    Labavić, Darka; Meyer-Ortmanns, Hildegard

    2017-08-01

    We analyze repulsively coupled Kuramoto oscillators, which are exposed to a distribution of natural frequencies. This source of disorder leads to closed orbits of repetitive temporary patterns of phase-locked motion, providing clocks on macroscopic time scales. The periods can be orders of magnitude longer than the periods of individual oscillators. By construction, the attractor space is quite rich. This may cause long transients until the deterministic trajectories find their stationary orbits. The smaller the width of the distribution about the common natural frequency, the longer are the emerging time scales on average. Among the long-period orbits, we find self-similar sequences of temporary phase-locked motion on different time scales. The ratio of time scales is determined by the ratio of widths of the distributions. The results illustrate a mechanism for how simple systems can provide rather flexible dynamics, with a variety of periods even without external entrainment.

  20. The coupling of dynamics and permeability in the hydrocarbon accumulation period controls the oil-bearing potential of low permeability reservoirs: a case study of the low permeability turbidite reservoirs in the middle part of the third member of Shahejie Formation in Dongying Sag

    OpenAIRE

    Yang, Tian; Cao, Ying-Chang; Wang, Yan-Zhong; FRIIS, Henrik; Haile, Beyene Girma; Xi, Ke-Lai; Zhang, Hu-Na

    2016-01-01

    The relationships between permeability and dynamics in hydrocarbon accumulation determine oilbearing potential (the potential oil charge) of low permeability reservoirs. The evolution of porosity and permeabilityof low permeability turbidite reservoirs of the middle part of the third member of the Shahejie Formation in the Dongying Sag has been investigated by detailed core descriptions, thin section analyses, fluid inclusion analyses, carbon and oxygen isotope analyses, mercury injection, po...

  1. Optical Periodicity Analysis of 3C 446 using Period04

    Indian Academy of Sciences (India)

    2016-01-27

    Jan 27, 2016 ... All the data of the blazar 3C446 at 8, 4.8, 14 and 22 GHz, presented in publications from 1977 to 2006, have been compiled to generate light curves. The light curves show violent activity of 3C446. Using Period04 analysis method, we have found that there is a period of 7.2 yr, which is consistent with the ...

  2. Formate Formation and Formate Conversion in Biological Fuels Production

    Directory of Open Access Journals (Sweden)

    Bryan R. Crable

    2011-01-01

    Full Text Available Biomethanation is a mature technology for fuel production. Fourth generation biofuels research will focus on sequestering CO2 and providing carbon-neutral or carbon-negative strategies to cope with dwindling fossil fuel supplies and environmental impact. Formate is an important intermediate in the methanogenic breakdown of complex organic material and serves as an important precursor for biological fuels production in the form of methane, hydrogen, and potentially methanol. Formate is produced by either CoA-dependent cleavage of pyruvate or enzymatic reduction of CO2 in an NADH- or ferredoxin-dependent manner. Formate is consumed through oxidation to CO2 and H2 or can be further reduced via the Wood-Ljungdahl pathway for carbon fixation or industrially for the production of methanol. Here, we review the enzymes involved in the interconversion of formate and discuss potential applications for biofuels production.

  3. The incubation period of kuru.

    Science.gov (United States)

    Huillard d'Aignaux, Jérôme N; Cousens, Simon N; Maccario, Jean; Costagliola, Dominique; Alpers, Michael P; Smith, Peter G; Alpérovitch, Annick

    2002-07-01

    Kuru is a transmissible spongiform encephalopathy that was identified in Papua New Guinea in the late 1950s. Several thousand cases of the disease occurred during a period of several decades. Epidemiologic investigations implicated ritual endocannibalistic funeral feasts as the likely route through which the infectious agent was spread. We estimated the incubation period distribution of kuru using a back-calculation model and explored the relation among sex, age at infection, and incubation period. Key assumptions in the model were that the number of new kuru infections in a year was proportional to the number of kuru cases dying that year, and that the epidemic arose from a single case of sporadic Creutzfeldt-Jakob Disease occurring around 1900. The mean incubation period of kuru was estimated at between 10.3 and 13.2 years. Point estimates of the 90th percentile ranged from 21.1 to 27.0 years. The incubation period in females was estimated to be shorter than that in males. The shortest incubation periods were estimated in adult women, who may have been exposed to the largest doses of infectious material. Our findings suggest that the relatively young age of cases of variant Creutzfeldt-Jakob disease probably reflects increased levels of exposure in young people, rather than age-dependency in the incubation period.

  4. Mercury's rotation axis and period

    Science.gov (United States)

    Klaasen, K. P.

    1976-01-01

    Recent measurements made from high-resolution Mariner 10 photography of the planet Mercury yield a rotation period of 58.6461 + or 0.005 days, in excellent agreement with the period required for a precise 2/3 resonance with its orbital period (58.6462 days). The axis of rotation of the planet was calculated to be offset about 2 deg from the perpendicular to its orbital plane within a 50% probability error ellipse of + or - 2.6 deg by + or - 6.5 deg. Dynamical considerations make it most likely that the true displacement from the orbit normal is less than 1 deg.

  5. Period Variations of RT Persei

    OpenAIRE

    Chun-Hwey Kim

    1995-01-01

    RT Per has been known as a close binary of which the orbital period has unpredictably varied so far. Although there are no agreements with the working mechanism for the changes of the period, two interpretations have been suggested and waiting for to be tested: 1)light-time effects due to the unseen 3rd and 4th bodies (Panchatsaram 1981), 2)Abrupt period-change due to internal variations of the system(e.q. mass transfer or mass loss) superimposing to the light-times effect by a 3rd body (Frie...

  6. The Periodic Table in Croatia

    Directory of Open Access Journals (Sweden)

    Raos, N.

    2011-12-01

    Full Text Available The Croatian (Yugoslav Academy of Sciences and Arts was the first academy to elect D. I. Mendeleev as its honorary member (1882, whereas the periodic table of the elements has been taught regularly at the Zagreb University since 1888. The early interest of Croatian chemists in the periodic table should be attributed primarily to their pan-Slavic attitude, particularly as proof that Slavic people were able to produce "their own Newtons" (M. V. Lomonosov and D. I. Mendeleev. Such enthusiastic views, however, did not help in analyzing the contribution of Mendeleev and other scientists to the discovery and development of the periodic table of the elements.

  7. Microspore derived embryo formation and doubled haploid plant ...

    African Journals Online (AJOL)

    Microspore-derived embryos (MDE) formation was influenced by the strength of the NLN medium, the microelement and sugar concentration, and the heat shock temperature and period. The 0.5XNLN liquid medium was the most favorable for MDE formation. The most efficient formation of MDE was observed in the 0.5X ...

  8. Rotation Periods of Wide Binaries in the Kepler Field

    Science.gov (United States)

    Janes, K. A.

    2017-01-01

    In a search of proper motion catalogs for common proper motion stars in the field of the Kepler spacecraft I identified 93 likely binary systems. A comparison of their rotation periods is a test of the gyrochronology concept. To find their periods I calculated the autocorrelation function (ACF) of the Kepler mission photometry for each star. In most systems for which good periods can be found, the cooler star has a longer period than the hotter component, in general agreement with models. However, there is a wide range in the gradients of lines connecting binary pairs in a period-color diagram. Furthermore, near the solar color, only a few stars have longer periods than the Sun, suggesting that they, and their cooler companions, are not much older than the Sun. In addition, there is an apparent gap at intermediate periods in the period distribution of the late K and early M stars. Either star formation in this direction has been variable, or stars evolve in period at a non-uniform rate, or some stars evolve more rapidly than others at the same mass. Finally, using the ACF as a measure of the activity level, I found that while the F, G, and early K stars become less active as their periods increase, there is no correlation between period and activity for the mid K to early M stars.

  9. Measuring Scars of Periodic Orbits

    CERN Document Server

    Kaplan, L

    1999-01-01

    The phenomenon of periodic orbit scarring of eigenstates of classically chaotic systems is attracting increasing attention. Scarring is one of the most important ``corrections'' to the ideal random eigenstates suggested by random matrix theory. This paper discusses measures of scars and in so doing also tries to clarify the concepts and effects of eigenfunction scarring. We propose a new, universal scar measure which takes into account an entire periodic orbit and the linearized dynamics in its vicinity. This measure is tuned to pick out those structures which are induced in quantum eigenstates by unstable periodic orbits and their manifolds. It gives enhanced scarring strength as measured by eigenstate overlaps and inverse participation ratios, especially for longer orbits. We also discuss off-resonance scars which appear naturally on either side of an unstable periodic orbit.

  10. Nonlinear waves in periodic media

    OpenAIRE

    Ketcheson, David; Luna, Manuel Quezada de

    2015-01-01

    This poster advertises several recent theoretical developments the computational modeling of nonlinear waves in periodic materials, by the Numerical Mathematics Group at KAUST.  The papers referenced in the poster are linked to below.

  11. Periodic progress report, 6 months

    DEFF Research Database (Denmark)

    Juhl, Thomas Winther; Nielsen, Jakob Skov

    This is the first progress report of the BriteEuram project named "High Power Laser Cutting for Heavy Industry" ("Powercut"). The report contains a summary of the objectives of the first period, an overview of the technical progress, a comparison between the planed and the accomplished work......, a description of the planned activities for the next period, and last comments on management and coordination....

  12. Vibration Control in Periodic Structures

    DEFF Research Database (Denmark)

    Høgsberg, Jan Becker

    2017-01-01

    Within the framework of periodic structures, the calibration of RL shunted piezoelectric inclusions is investigated with respect to maximum damping of a particular wave form. A finite element setting is assumed, with local shunted inclusions inside the unit cell. The effect of the shunts is repre....... The presentation contains dispersion diagrams and vibration amplitude curves for the optimally calibrated RL shunt system in a 1-D periodic structure with local piezoelectric inclusions....

  13. 78 FR 70904 - Periodic Reporting

    Science.gov (United States)

    2013-11-27

    ... Counsel, at 202-789-6820. SUPPLEMENTARY INFORMATION: Table of Contents I. Introduction II. Petition III... ``reflecting the classification structure in the Mail Classification Schedule.'' The same rule also calls for ``an alternative, more disaggregated format capable of reflecting the classification structure in...

  14. Period proliferation in periodic states in cyclically sheared jammed solids

    Science.gov (United States)

    Lavrentovich, Maxim O.; Liu, Andrea J.; Nagel, Sidney R.

    2017-08-01

    Athermal disordered systems can exhibit a remarkable response to an applied oscillatory shear: After a relatively few shearing cycles, the system falls into a configuration that had already been visited in a previous cycle. After this point the system repeats its dynamics periodically despite undergoing many particle rearrangements during each cycle. We study the behavior of orbits as we approach the jamming point in simulations of jammed particles subject to oscillatory shear at fixed pressure and zero temperature. As the pressure is lowered, we find that it becomes more common for the system to find periodic states where it takes multiple cycles before returning to a previously visited state. Thus, there is a proliferation of longer periods as the jamming point is approached.

  15. Old Dogs Learning New Tricks: Neuroplasticity beyond the Juvenile Period

    Science.gov (United States)

    Lillard, Angeline S.; Erisir, Alev

    2011-01-01

    Twenty years ago, the prevalent view in Psychology was that although learning and the formation of new memories are lifelong occurrences, the neural changes associated with these events were all in the existing receptors. No new neural hardware, from synapses to neurons, was thought to appear after a protracted period early in life. In the past 20…

  16. Copernican Mathematics: Calculating Periods and Distances of the Planets

    Science.gov (United States)

    Rosenkrantz, Kurt J.

    2004-01-01

    The heliocentric, or Sun-centered model, one of the most important revolutions in scientific thinking, allowed Nicholas Copernicus to calculate the periods, relative distances, and approximate orbital shapes of all the known planets, thereby paving the way for Kepler's laws and Newton's formation of gravitation. Recreating Copernicus's…

  17. Complications and mortality following stoma formation.

    Science.gov (United States)

    Harris, D. A.; Egbeare, D.; Jones, S.; Benjamin, H.; Woodward, A.; Foster, M. E.

    2005-01-01

    INTRODUCTION: As stoma formation is thought to be declining, we performed a study to evaluate the rate of stoma formation and the impact on stoma complication rates, together with risk factors for complications. PATIENTS AND METHODS: Stoma incidence, individual complications and mortality rates were retrieved from a stoma nurse database of 345 stomas created over an 8-year period. RESULTS: Stoma formation increased over the study period, although the incidence of complications declined. Stoma complications were more frequently seen in emergency surgery. A significant association between stoma complications and mortality was identified. CONCLUSIONS: Age of patient, urgency of surgery and diagnosis were associated with high levels of morbidity and mortality. Stomas are often formed in frail patients unsuitable for anastomosis formation, which may explain the high mortality in ostomy patients. PMID:16263009

  18. C-type period-doubling transition in nephron autoregulation

    DEFF Research Database (Denmark)

    Laugesen, Jakob Lund; Mosekilde, Erik; Holstein-Rathlou, Niels-Henrik

    2011-01-01

    -doubling bifurcations, mode-locking and other nonlinear dynamic phenomena in the tubular pressures and flows. Using a simplified nephron model, the paper examines how the regulatory mechanisms react to an external periodic variation in arterial pressure near a region of resonance with one of the internally generated...... mode-locked cycles. We show how the stable and unstable resonance cycles generated in this response undergo interconnected cascades of period-doubling bifurcations and how each period doubling leads to the formation of a new pair of saddle-node bifurcation curves along the edges of the resonance zone...

  19. Ionospheric irregularities in periods of meteorological disturbances

    Science.gov (United States)

    Borchevkina, O. P.; Karpov, I. V.

    2017-09-01

    The results of observations of the total electron content (TEC) in periods of storm disturbances of meteorological situation are presented in the paper. The observational results have shown that a passage of a meteorological storm is accompanied by a substantial decrease in values of TEC and critical frequencies of the ionospheric F2 region. The decreases in values of these ionospheric parameters reach 50% and up to 30% in TEC and critical frequency of the F2 layer, respectively, as compared to meteorologically quiet days. Based on qualitative analysis, it is found that the processes related to formation of local regions of thermospheric heating due to a dissipation of AGW coming into the upper atmosphere from the region of the meteorological disturbance in the lower atmosphere are a possible cause of these ionospheric disturbances.

  20. The Format Dilemma.

    Science.gov (United States)

    Oder, Norman

    2002-01-01

    Reports results of a survey of public libraries that investigated trends in audiovisual materials. Highlights include format issues; audiobooks; media budgets for various formats; video collections; DVDs; circulation; collection sizes; music CDs; and future possibilities. (LRW)

  1. THE INDUCTION PERIOD IN PHOTOSYNTHESIS.

    Science.gov (United States)

    Smith, E L

    1937-11-20

    1. Measurements on the photosynthesis of Cabomba caroliniana show an induction period at low and high light intensities and CO(2) concentrations. 2. The equation which describes the data for Cabomba also describes the data obtained by other investigators on different species. The phenomenon is thus shown to be similar in plants representative of three phyla. 3. A derivation of the induction period equation is made from a consideration of the cycle of light and dark processes known to occur in photosynthesis. The equation indicates that light intensity enters as the square, and that the same light reactions are involved as those which affect the stationary state rates. However, a different dark reaction appears to limit photosynthesis during the induction period.

  2. Period Variations of RT Persei

    Directory of Open Access Journals (Sweden)

    Chun-Hwey Kim

    1995-12-01

    Full Text Available RT Per has been known as a close binary of which the orbital period has unpredictably varied so far. Although there are no agreements with the working mechanism for the changes of the period, two interpretations have been suggested and waiting for to be tested: 1light-time effects due to the unseen 3rd and 4th bodies (Panchatsaram 1981, 2Abrupt period-change due to internal variations of the system(e.q. mass transfer or mass loss superimposing to the light-times effect by a 3rd body (Frieboes-Conde & Herczeg 1973. In the point of view that the former interprepation models could predict the behavior of the changes of the orbital period theoretically, we checked whether the recent observed times of minimum lights follow the predictions by the first model or not. We confirmed that the observed times of minimum lights have followed the variations calculated by the light-times effects due to 3rd and 4th bodies suggested by Panchatsaram. In this paper a total of 626 times of minimum lights were reanalyzed in terms of the light-time effects by the 3rd and 4th bodies. We concluded that the eclipsing pair in SV Cam system moves in an elliptic orbit about center of mass of the triple system with a period of about 42.y2, while the mass center of the triplet is in light-time orbit about the center of mass of the quadruple system with a period of 120y. The mean masses deduced for the 3rd and 4th bodies were 0.89m⨀ and 0.82m⨀, respectively.

  3. Sigmoid Volvulus Complicating Postpartum Period

    Directory of Open Access Journals (Sweden)

    Kelsey E. Ward

    2017-01-01

    Full Text Available Background. Sigmoid volvulus is a rare complication of pregnancy and the puerperium. Case. A 19-year-old patient, gravida 1 para 0 at 41 0/7 weeks of gestation, admitted for late-term induction of labor underwent an uncomplicated primary low transverse cesarean delivery for arrest of descent. Her postoperative period was complicated by sudden onset of abdominal pain and the ultimate diagnosis of sigmoid volvulus. Conclusion. Prompt surgical evaluation of an acute abdomen in the postpartum period is essential; delayed diagnosis and treatment can lead to significant maternal morbidity and mortality.

  4. Formate Formation and Formate Conversion in Biological Fuels Production

    NARCIS (Netherlands)

    Crable, B.R.; Plugge, C.M.; McInerney, M.J.; Stams, A.J.M.

    2011-01-01

    Biomethanation is a mature technology for fuel production. Fourth generation biofuels research will focus on sequestering CO2 and providing carbon-neutral or carbon-negative strategies to cope with dwindling fossil fuel supplies and environmental impact. Formate is an important intermediate in the

  5. Pairs of dual periodic frames

    DEFF Research Database (Denmark)

    Christensen, Ole; Goh, Say Song

    2012-01-01

    is needed. The purpose of the present paper is to provide constructions of dual pairs of frames in the setting of the Hilbert space of periodic functions L2(0,2π). The frames constructed are given explicitly as trigonometric polynomials, which allows for an efficient calculation of the coefficients...

  6. Glass Waveguides for Periodic Poling

    DEFF Research Database (Denmark)

    Fage-Pedersen, Jacob; Jacobsen, Rune Shim; Kristensen, Martin

    2005-01-01

    Planar silica-based waveguide devices have been developed for second-harmonic generation by poling with periodic electrodes. We show that detrimental charge transport can occur along interfaces, but with proper choice of fabrication, high-quality devices are obtained....

  7. Soliton Management in Periodic Systems

    CERN Document Server

    Malomed, Boris A

    2006-01-01

    During the past ten years, there has been intensive development in theoretical and experimental research of solitons in periodic media. This book provides a unique and informative account of the state-of-the-art in the field. The volume opens with a review of the existence of robust solitary pulses in systems built as a periodic concatenation of very different elements. Among the most famous examples of this type of systems are the dispersion management in fiber-optic telecommunication links, and (more recently) photonic crystals. A number of other systems belonging to the same broad class of spatially periodic strongly inhomogeneous media (such as the split-step and tandem models) have recently been identified in nonlinear optics, and transmission of solitary pulses in them was investigated in detail. Similar soliton dynamics occurs in temporal-domain counterparts of such systems, where they are subject to strong time-periodic modulation (for instance, the Feshbach-resonance management in Bose-Einstein conde...

  8. Period persistence of long period oscillations in sunspots

    Science.gov (United States)

    Chorley, N.; Foullon, C.; Hnat, B.; Nakariakov, V. M.; Shibasaki, K.

    2011-05-01

    Long period oscillations in the microwave radiation intensity generated over the sunspot of NOAA AR 10330 are studied with the Nobeyama Radioheliograph as the sunspot passes over the solar disk, over the course of 9 days (06-15 April 2003). Periodogram, Fourier and global wavelet analyses reveal the presence of a significant oscillatory component in the range P ≈ 50-120 min over the course of the observations. The spectral amplitudes of five significant Fourier components in the range P = 50-150 min are also seen to be stable over the observations, when the data are not affected by changes in magnetic configuration in the region. The ground-based nature of the instrument naturally introduces long data gaps in such long duration observations and the presence of the gaps does not allow any conclusion as to the stability of the phases of the oscillations. As a model to explain the persistence of the dominant long periods, a simple oscillator with a nonlinear driving term is proposed. The spectral difference between distinct peaks within, e.g. the 3 min spectral band, is expected to be able to resonate with the long period one hour oscillations.

  9. Periodic Convergences: Dance and Computers

    OpenAIRE

    deLahunta, Scott

    2002-01-01

    Published in German and English, this chapter is one of deLahunta's major outputs to emerge from a group of related research outputs, concerning "dance and technology". In it he explores the history of the convergence between dance and computers from the 1960s to the 1990s, arguing that this convergence has been periodic, involving particular artists at particular times, rather than producing a genre of work (as others have speculated). As the mainstream of contemporary dance evolved alongsid...

  10. Neuroethology of prey capture in the barn owl (Tyto alba L.).

    Science.gov (United States)

    Wagner, Hermann; Kettler, Lutz; Orlowski, Julius; Tellers, Philipp

    2013-01-01

    Barn owls are a model system for studying prey capture. These animals can catch mice by hearing alone, but use vision whenever light conditions allow this. The silent flight, the frontally oriented eyes, and the facial ruffs are specializations that evolved to optimize prey capture. The auditory system is characterized by high absolute sensitivity, a use of interaural time difference for azimuthal sound-localization over almost the total hearing range up to at least 9 kHz, and the use of interaural level difference for elevational sound localization in the upper frequency range. Response latencies towards auditory targets were shortened by covert attention, while overt attention helped to orient towards salient visual objects. However, only 20% of the fixation movements could be explained by the saliency of the fixated objects, suggesting a top-down control of attention. In a visual-search experiment the birds turned earlier and more often towards and spent more time at salient objects. The visual system also exhibits high absolute sensitivity, while the spatial resolution is not particularly high. Last but not least, head movements may be classified as fixations, translations, and rotations combined with translations. These motion primitives may be combined to complex head-movement patterns. With the expected easy availability of genetic techniques for specialists in the near future and the possibility to apply the findings in biomimetic devices prey capture in barn owls will remain an exciting field in the future. Copyright © 2012 Elsevier Ltd. All rights reserved.

  11. From classic ethology to modern neuroethology: overcoming the three biases in social behavior research.

    Science.gov (United States)

    Zilkha, Noga; Sofer, Yizhak; Beny, Yamit; Kimchi, Tali

    2016-06-01

    A typical current study investigating the neurobiology of animal behavior is likely restricted to male subjects, of standard inbred mouse strains, tested in simple behavioral assays under laboratory conditions. This approach enables the use of advanced molecular tools, alongside standardization and reproducibility, and has led to tremendous discoveries. However, the cost is a loss of genetic and phenotypic diversity and a divergence from ethologically-relevant behaviors. Here we review the pros and cons in behavioral neuroscience studies of the new era, focusing on reproductive behaviors in rodents. Recent advances in molecular technology and behavioral phenotyping in semi-natural conditions, together with an awareness of the critical need to study both sexes, may provide new insights into the neural mechanisms underlying social behaviors. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. A multi-period group technology method for dynamic cellular manufacturing systems

    Directory of Open Access Journals (Sweden)

    Padayachee, Jared

    2016-12-01

    Full Text Available A dynamic cellular manufacturing system is a system where cell configurations change in order to respond to changing production requirements. This paper proposes methods for multi-period cell and part family formation. The method of fuzzy C-means clustering is used for part family formation while balancing the part load between cells in each period; a genetic algorithm is presented to solve the model. An integer programming model is presented for multi-period cell formation with the objective of determining an optimal trade-off between reconfiguration cost and the cost of deficit capacity.

  13. 77 FR 27125 - Periodicals-Recognition of Distribution of Periodicals via Electronic Copies

    Science.gov (United States)

    2012-05-09

    ... 111 Periodicals--Recognition of Distribution of Periodicals via Electronic Copies AGENCY: Postal... copies of Periodicals publications to satisfy the circulation standards for Periodicals qualification... Service published a Federal Register proposed rule Periodicals--Recognition of Distribution of Periodicals...

  14. Objetivos y metodologías en los estudios de evaluación formativa de la composición escrita entre el periodo de 1992 y 2014 / Objectives and methodologies in studies of formative assessment of written composition between the period 1992 and 2014

    Directory of Open Access Journals (Sweden)

    Silvana de la Hoz Ibacache

    2016-09-01

    Full Text Available Resumen: El propósito de la presente investigación es analizar la evaluación formativa del proceso de escritura mediante una revisión bibliográfica comprendida entre los años 1992 y 2014 dentro del área hispanohablante. Para lograrlo se recogen 73 documentos que son analizados cualitativamente a través de la técnica del análisis de contenido. Los resultados indican que existen divergencias relacionadas con los procesos investigados. Además, tales divergencias se implementan bajo marcos de intervención distintos, es decir, mientras algunas realizan intervenciones específicas para obtener cierta información del proceso de evaluación de la producción textual, otras realizan implementaciones bajo el marco de secuencias didácticas, lo que produce resultados y reflexiones en distintas direcciones. Abstract: The purpose of the current research is to analyze formative assessment of writing through literature review between the years 1992 and 2014 in Spanish-speaking area. In order to achieve this, 73 documents were collected and analyzed qualitatively with the content analysis technique. The results indicate that there are divergences related to the processes investigated. Additionally, these divergences are implemented under different intervention frames, in other words, while some of them make specific interventions to extract information about the writing assessment process, the other ones make implementations under the framework of didactic sequences, producing results and reflections in different ways.

  15. 7 CFR 1160.113 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Fiscal period. 1160.113 Section 1160.113 Agriculture... Definitions § 1160.113 Fiscal period. Fiscal period means the initial period of up to 30 months that this subpart is effective. Thereafter, the fiscal period shall be such annual period as the Board may determine...

  16. The Conic Benchmark Format

    DEFF Research Database (Denmark)

    Friberg, Henrik A.

    This document constitutes the technical reference manual of the Conic Benchmark Format with le extension: .cbf or .CBF. It unies linear, second-order cone (also known as conic quadratic) and semidenite optimization with mixed-integer variables. The format has been designed with benchmark libraries...... in mind, and therefore focuses on compact and easily parsable representations. The problem structure is separated from the problem data, and the format moreover facilitate benchmarking of hotstart capability through sequences of changes....

  17. Periodic permanent magnet focused klystron

    Energy Technology Data Exchange (ETDEWEB)

    Ferguson, Patrick; Read, Michael; Ives, R Lawrence

    2015-04-21

    A periodic permanent magnet (PPM) klystron has beam transport structures and RF cavity structures, each of which has permanent magnets placed substantially equidistant from a beam tunnel formed about the central axis, and which are also outside the extent of a cooling chamber. The RF cavity sections also have permanent magnets which are placed substantially equidistant from the beam tunnel, but which include an RF cavity coupling to the beam tunnel for enhancement of RF carried by an electron beam in the beam tunnel.

  18. Fixed points of periodic maps.

    Science.gov (United States)

    Cappell, S E; Shaneson, J L

    1980-09-01

    Let f be a periodic differentiable map from a sphere to itself. A well-known conjecture of Smith asserts that in many cases (e.g., when the fixed points are isolated) the derivatives of f at its fixed points, regarded as Jacobian matrices, are linearly similar. Here we give counterexamples to this conjecture. The results show that, in many cases, these Jacobian matrices are only nonlinearly similar. This uses our recent discovery of orthogonal matrices which are nonlinearly similar without being linearly similar. Some results on general smooth actions of finite groups on differentiable manifolds are presented; the topological equivalence of their tangential representations at the fixed points is studied.

  19. Mining Association Rules in Dengue Gene Sequence with Latent Periodicity

    Directory of Open Access Journals (Sweden)

    Marimuthu Thangam

    2015-01-01

    Full Text Available The mining of periodic patterns in dengue database is an interesting research problem that can be used for predicting the future evolution of dengue viruses. In this paper, we propose an algorithm called Recurrence Finder (RECFIN that uses the suffix tree for detecting the periodic patterns of dengue gene sequence. Also, the RECFIN finds the presence of palindrome which indicates the possibilities of formation of proteins. Further, this paper computes the periodicity of nucleic acid and amino acid sequences of any length. The periodicity based association rules are used to diagnose the type of dengue. The time complexity of the proposed algorithm is O(n2. We demonstrate the effectiveness of the proposed approach by comparing the experimental results performed on dengue virus serotypes dataset with NCBI-BLAST algorithm.

  20. Periodic Hydraulic Tests in a Bedrock Fracture Network

    Science.gov (United States)

    Cole, M. C.; Becker, M.; Ciervo, C.

    2016-12-01

    Better understanding of groundwater flow through bedrock fracture networks is critical for the emerging field of enhanced geothermal systems, as well as traditional hydrogeologic characterization. Periodic hydraulic testing has shown promise for its sensitivity to local heterogeneity and, therefore, may provide useful information about flow channelization and short circuiting. Unlike conventional steady-rate pumping or injection tests, periodic tests create a disturbance such that heads in the pumping and observation wells are always in the transient state. The volume of hydraulic influence of the oscillating flow increases with period of oscillation. Thus, different portions of the formation may be interrogated even with a single well pair. We recently performed periodic pumping tests at the Mirror Lake experimental fractured rock hydrology field site in the Northeastern United States. Head in one well was oscillated while heads in five monitoring wells 30 to 60 m away were monitored. Head oscillation was accomplished through alternating injection and pumping from a surface tank and pressure was measured using a network of transducers in zones isolated by pneumatic packers. Periodicity of the induced signal was varied in order to investigate different volumes of the formation. Drawdown data from the monitoring wells were digitally filtered, which enabled use of responses that were too small or noisy for curve fitting methods. As expected, the volume of hydraulic influence increased with period, but well response was not strictly a function of distance from the source well. This anomalous response is attributed to variation in fracture network hydraulic connectivity. The ability to vary the effective penetration distance of hydraulic influence provided more information about network connectivity than from a constant rate pumping test. Estimates of hydraulic parameters displayed a decreasing trend with period length, which has been noted in previous periodic tests

  1. [Changes in physical endurance following a 3-months' exam period].

    Science.gov (United States)

    Hentschel, E; Scheuch, K; Gruber, G; Pietruschka, W D

    1984-05-01

    The question was raised to what extent in the course of a three-month examination period as a time of increased psychic stress, depending upon the distinction of the personal peculiarity "fear of examinations" of the students, reductions of the physical efficiency develop. On the basis of the lactate efficiency curves a significant decrease in vitality after a three-month examination period was proved. The determination of the efficiency in the aerobic-anaerobic transitional zone renders possible an exact evidence, independent upon motivation. According to the results the formation of the curriculum has a determining influence on the physical efficiency, however, not the personal peculiarity "fear of examinations".

  2. Formative Assessment Probes

    Science.gov (United States)

    Eberle, Francis; Keeley, Page

    2008-01-01

    Formative assessment probes can be effective tools to help teachers build a bridge between students' initial ideas and scientific ones. In this article, the authors describe how using two formative assessment probes can help teachers determine the extent to which students make similar connections between developing a concept of matter and a…

  3. Exploring Opponent Formats

    DEFF Research Database (Denmark)

    Jensen, Mads Møller; Rasmussen, Majken; Grønbæk, Kaj

    2013-01-01

    of how the opponent format and relationships impact a game are almost absent in current research. Thus, this paper aims to elucidate how the perception of a competition differs, depending on the opponent format, by presenting a game mechanic framework. The paper furthermore presents an interactive...

  4. Usage Record Format Recommendation

    CERN Document Server

    Nilsen, J.K.; Muller-Pfeerkorn, R

    2013-01-01

    For resources to be shared, sites must be able to exchange basic accounting and usage data in a common format. This document describes a common format which enables the exchange of basic accounting and usage data from different resources. This record format is intended to facilitate the sharing of usage information, particularly in the area of the accounting of jobs, computing, memory, storage and cloud usage but with a structure that allows an easy extension to other resources. This document describes the Usage Record components both in natural language form and annotated XML. This document does not address how these records should be used, nor does it attempt to dictate the format in which the accounting records are stored. Instead, it denes a common exchange format. Furthermore, nothing is said regarding the communication mechanisms employed to exchange the records, i.e. transport layer, framing, authentication, integrity, etc.

  5. A periodic table for cancer.

    Science.gov (United States)

    Epstein, Richard J

    2015-01-01

    Cancers exhibit differences in metastatic behavior and drug sensitivity that correlate with certain tumor-specific variables such as differentiation grade, growth rate/extent and molecular regulatory aberrations. In practice, patient management is based on the past results of clinical trials adjusted for these biomarkers. Here, it is proposed that treatment strategies could be fine-tuned upfront simply by quantifying tumorigenic spatial (cell growth) and temporal (genetic stability) control losses, as predicted by genetic defects of cell-cycle-regulatory gatekeeper and genome-stabilizing caretaker tumor suppressor genes, respectively. These differential quantifications of tumor dysfunction may in turn be used to create a tumor-specific 'periodic table' that guides rational formulation of survival-enhancing anticancer treatment strategies.

  6. The periodic table in Flatland

    Energy Technology Data Exchange (ETDEWEB)

    Negadi, T. [Universite d`Oran, Es-Senia (Algeria); Kibler, M. [Universite Claude Bernard, Villeurbanne (France)

    1996-01-05

    The D-dimensional Coulomb system serves as a starting point for generating generalized atomic shells. These shells are ordered according to a generalized Madelung rule in D dimensions. This rule together with an Aujbau Prinzip is applied to produce a D-dimensional periodic table. A model is developed to rationalize the ordering of the shells predicted by the generalized Madelung rule. This model is based on the introduction of a Hamiltonian, invariant under the q-deformed algebra U{sub q}(so(D)), that breaks down the SO(D + 1) dynamical symmetry of the hydrogen atom in D dimensions. The D = 2 case (Flatland) is investigated in some detail. It is shown that the neutral atoms and the (moderately) positive ions correspond to the values q = 0.8 and q = 1, respectively, of the deformation parameter q. 55 refs.

  7. Active particles in periodic lattices

    Science.gov (United States)

    Chamolly, Alexander; Ishikawa, Takuji; Lauga, Eric

    2017-11-01

    Both natural and artificial small-scale swimmers may often self-propel in environments subject to complex geometrical constraints. While most past theoretical work on low-Reynolds number locomotion addressed idealised geometrical situations, not much is known on the motion of swimmers in heterogeneous environments. As a first theoretical model, we investigate numerically the behaviour of a single spherical micro-swimmer located in an infinite, periodic body-centred cubic lattice consisting of rigid inert spheres of the same size as the swimmer. Running a large number of simulations we uncover the phase diagram of possible trajectories as a function of the strength of the swimming actuation and the packing density of the lattice. We then use hydrodynamic theory to rationalise our computational results and show in particular how the far-field nature of the swimmer (pusher versus puller) governs even the behaviour at high volume fractions.

  8. 7 CFR 929.106 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Fiscal period. 929.106 Section 929.106 Agriculture... LONG ISLAND IN THE STATE OF NEW YORK Rules and Regulations § 929.106 Fiscal period. The fiscal period... include the period of August 1, through August 31, 1968. Thereafter, the fiscal period will begin on...

  9. 7 CFR 1221.10 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Fiscal period. 1221.10 Section 1221.10 Agriculture... INFORMATION ORDER Sorghum Promotion, Research, and Information Order Definitions § 1221.10 Fiscal period. Fiscal period means the 12-month period ending on December 31 or such other consecutive 12-month period...

  10. 7 CFR 955.113 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Fiscal period. 955.113 Section 955.113 Agriculture... and Regulations § 955.113 Fiscal period. Pursuant to § 955.13, fiscal period shall mean the period beginning January 1 and ending December 31 of each year, except that the fiscal period that began on...

  11. 7 CFR 930.7 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Fiscal period. 930.7 Section 930.7 Agriculture... Definitions § 930.7 Fiscal period. Fiscal period is synonymous with fiscal year and means the 12-month period... Board, with the approval of the Secretary, may establish: Provided, that the initial fiscal period shall...

  12. Sex differences in the formation of coalitions among chimpanzees

    NARCIS (Netherlands)

    Waal, F.B.M. de

    1984-01-01

    Observations were made of spontaneous coalition formation during aggressive encounters among chimpanzees in a large, semicaptive colony. The analysis of several thousand instances, collected over a period of 5 years, revealed striking differences between adult males and females. Male coalitions

  13. Parabolic Free Boundary Price Formation Models Under Market Size Fluctuations

    KAUST Repository

    Markowich, Peter A.

    2016-10-04

    In this paper we propose an extension of the Lasry-Lions price formation model which includes uctuations of the numbers of buyers and vendors. We analyze the model in the case of deterministic and stochastic market size uctuations and present results on the long time asymptotic behavior and numerical evidence and conjectures on periodic, almost periodic, and stochastic uctuations. The numerical simulations extend the theoretical statements and give further insights into price formation dynamics.

  14. Manuel UNIMARC format bibliographique

    CERN Document Server

    2007-01-01

    This manual is the French translation of the second edition of UNIMARC Manual: bibliographic format published in English in 1994 and completed by 5 updates published from 1996 to 2005. This 5th French edition is composite. It reproduces identically a part of the 4th edition published in 2002 and, for the fields of the format modified in the Update 5, it offers a new more structured presentation. This is a handbook dedicated to French-speaking users of the UNIMARC format for bibliographic descriptions.

  15. 75 FR 41989 - Content of Periodicals Mail

    Science.gov (United States)

    2010-07-20

    ... 111 Content of Periodicals Mail AGENCY: Postal Service TM . ACTION: Final rule. SUMMARY: The Postal....3, to update present ``content requirements'' on materials eligible for mailing at Periodicals prices with authorized Periodicals publications. DATES: Effective September 7, 2010. FOR FURTHER...

  16. Time—periodic weak solutions

    Directory of Open Access Journals (Sweden)

    Eliana Henriques de Brito

    1990-01-01

    Full Text Available In continuing from previous papers, where we studied the existence and uniqueness of the global solution and its asymptotic behavior as time t goes to infinity, we now search for a time-periodic weak solution u(t for the equation whose weak formulation in a Hilbert space H isddt(u′,v+δ(u′,v+αb(u,v+βa(u,v+(G(u,v=(h,vwhere: ′=d/dt; (′ is the inner product in H; b(u,v, a(u,v are given forms on subspaces U⊂W, respectively, of H; δ>0, α≥0, β≥0 are constants and α+β>0; G is the Gateaux derivative of a convex functional J:V⊂H→[0,∞ for V=U, when α>0 and V=W when α=0, hence β>0; v is a test function in V; h is a given function of t with values in H.

  17. Dynamical diffraction in periodic multilayers

    CERN Document Server

    Sears, V F

    1997-01-01

    Exact reflectivity curves are calculated numerically for various periodic multilayers using the optical matrix method in order to test the dynamical theory of diffraction. The theory is generally valid for values of the bilayer thickness d up to about 100 A. For somewhat larger values of d, where the theory begins to break down, the initial discrepancy is in the phase of the oscillations in the wings of the peaks. For very large values of d, where the first-order Bragg peak approaches the edge of the mirror reflection, two general types of multilayers can be distinguished. In the first (typified in the present work by Ni/Ti), there is a large (30% or more) reduction in the actual value of the critical wave vector for total reflection while, in the second (typified here by Fe/Ge), there is very little reduction (3 % or so). The origin of these two very different types of behavior is explained. It is also shown that, within the dynamical theory of diffraction, the change in the position of the center of the Dar...

  18. Concept Formation Skills in Long-Term Cochlear Implant Users

    Science.gov (United States)

    Castellanos, Irina; Kronenberger, William G.; Beer, Jessica; Colson, Bethany G.; Henning, Shirley C.; Ditmars, Allison; Pisoni, David B.

    2015-01-01

    This study investigated if a period of auditory sensory deprivation followed by degraded auditory input and related language delays affects visual concept formation skills in long-term prelingually deaf cochlear implant (CI) users. We also examined if concept formation skills are mediated or moderated by other neurocognitive domains (i.e.,…

  19. Multimodal pore formation in calcium phosphate cements.

    Science.gov (United States)

    Lodoso-Torrecilla, Irene; van Gestel, Nicole A P; Diaz-Gomez, Luis; Grosfeld, Eline-Claire; Laperre, Kjell; Wolke, Joop G C; Smith, Brandon T; Arts, Jacobus J; Mikos, Antonios G; Jansen, John A; Hofmann, Sandra; van den Beucken, Jeroen J J P

    2017-09-23

    Calcium phosphate cements (CPCs) are commonly used as bone substitute materials. However, their slow degradation rate and lack of macroporosity hinders new bone formation. Poly(dl-lactic-co-glycolic acid) (PLGA) incorporation is of great interest as, upon degradation, produces acidic by-products that enhance CPC degradation. Yet, new bone formation is delayed until PLGA degradation occurs a few weeks after implantation. Therefore, the aim of this study was to accelerate the early stage pore formation within CPCs in vitro. With that purpose, we incorporated the water-soluble porogen sucrose at different weight percentages (10 or 20 wt %) to CPC and CPC/PLGA composites. The results revealed that incorporation of sucrose porogens increased mass loss within the first week of in vitro degradation in groups containing sucrose compared to control groups. After week 1, a further mass loss was observed related to PLGA and CPC degradation. Macroporosity analysis confirmed that macroporosity formation is influenced by the dissolution of sucrose at an early stage and by the degradation of PLGA and CPC at a later stage. We concluded that the combination of sucrose and PLGA porogens in CPC is a promising approach to promote early stage bone tissue ingrowth and complete replacement of CPC through multimodal pore formation. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2017. © 2017 Wiley Periodicals, Inc.

  20. PCF File Format.

    Energy Technology Data Exchange (ETDEWEB)

    Thoreson, Gregory G [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-08-01

    PCF files are binary files designed to contain gamma spectra and neutron count rates from radiation sensors. It is the native format for the GAmma Detector Response and Analysis Software (GADRAS) package [1]. It can contain multiple spectra and information about each spectrum such as energy calibration. This document outlines the format of the file that would allow one to write a computer program to parse and write such files.

  1. Plant Formate Dehydrogenase

    Energy Technology Data Exchange (ETDEWEB)

    John Markwell

    2005-01-10

    The research in this study identified formate dehydrogenase, an enzyme that plays a metabolic role on the periphery of one-carbon metabolism, has an unusual localization in Arabidopsis thaliana and that the enzyme has an unusual kinetic plasticity. These properties make it possible that this enzyme could be engineered to attempt to engineer plants with an improved photosynthetic efficiency. We have produced transgenic Arabidopsis and tobacco plants with increased expression of the formate dehydrogenase enzyme to initiate further studies.

  2. Crystal formation in furunculosis agar

    Science.gov (United States)

    Bullock, G.L.; Ross, A.J.

    1964-01-01

    SINCE ITS INTRODUCTION SOME MONTHS AGO, FURUNCULOSIS AGAR has been employed in the diagnosis of suspect furunculosis and also as a general purpose medium. During our work with this medium we have noticed discrete "colonies," of crystalline material, which very closely resemble microbial colonies. These crystal colonies are compact and appear on both the surface and subsurface; they occur in inoculated slants and plates incubated for long periods (2 to 3 weeks), as well as in uninoculated stored medium. As the crystal colonies could be confusing to workers using this medium, we decided to attempt to identify them and also to determine whether storage conditions and different lots of medium affect crystal formation.

  3. Intraseasonal Periodicities in Indian Rainfall.

    Science.gov (United States)

    Hartmann, Dennis L.; Michelsen, Marc L.

    1989-09-01

    Spectral analysis of a 70-year (1901-70) record of daily precipitation from 3700 stations in the country of India is carried out to search for periodicities on subseasonal time scales during the summer monsoon. Two statistically significant spectral peaks are found. A 40-50 day spectral peak corresponding to the Madden-Julian Oscillation is found over most of the portion of India south of 23°N. The phase of the oscillation is such that the precipitation maximum appears first over the relatively dry southeastern portion of the peninsula. Ten to 12 days later the precipitation peaks simultaneously all along the coast west of the Western Ghats and along a line running across India between 20° and 25°N. The precipitation maximum then spreads slowly northward and loses significance.Cross-spectral analysis shows strong coherence between the precipitation patterns and wind oscillations. The zonal wind oscillations at 850 and 200 mb am about 180 degrees out-of-phase equatorward of about 20°N, but in-phase poleward of 20°N. Compositing of the 40-50 day variance shows the structure of the wind variations associated with the precipitation cycle over India. At the southern tip and along the west coast of India, precipitation variations on the 40-50 day time scale seem to be, at least in part, orographically controlled, with upslope winds simultaneous with the precipitation maxima. In central India the precipitation maxima are more closely related to large-scale divergence and convergence patterns, with the largest precipitation clearly associated with cyclonic circulations at low levels which have about the same horizontal structure as the precipitation maximum.In addition to the 40-50 day oscillation, significant spectral peaks and coherent structures in precipitation are found whose characteristics correspond to those of monsoon lows. These are associated with a peak in the precipitation spectrum between about 5 and 7 days, which is strongest on the Bay of Bengal coast

  4. 39 CFR 121.2 - Periodicals.

    Science.gov (United States)

    2010-07-01

    ... 39 Postal Service 1 2010-07-01 2010-07-01 false Periodicals. 121.2 Section 121.2 Postal Service... § 121.2 Periodicals. (a) End-to-End. (1) For all SCF turnaround Periodicals properly accepted before the... through 99591), 996, 997, 998, and 999. (2) The Periodicals service standard is the sum of the applicable...

  5. 7 CFR 966.16 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Fiscal period. 966.16 Section 966.16 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Regulating Handling Definitions § 966.16 Fiscal period. Fiscal period means the period beginning August 1 and...

  6. 7 CFR 948.103 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Fiscal period. 948.103 Section 948.103 Agriculture... Rules and Regulations General § 948.103 Fiscal period. Pursuant to § 948.10, the fiscal periods for each... following year, both dates inclusive. The 1986-87 fiscal period which began July 1, 1986, will be extended...

  7. 7 CFR 1220.111 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Fiscal period. 1220.111 Section 1220.111 Agriculture... CONSUMER INFORMATION Soybean Promotion and Research Order Definitions § 1220.111 Fiscal period. The term fiscal period means the calendar year or such other annual period as the Board may determine with the...

  8. 7 CFR 927.9 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Fiscal period. 927.9 Section 927.9 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Order Regulating Handling Definitions § 927.9 Fiscal period. Fiscal period means the period beginning...

  9. 7 CFR 923.7 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Fiscal period. 923.7 Section 923.7 Agriculture... COUNTIES IN WASHINGTON Order Regulating Handling Definitions § 923.7 Fiscal period. Fiscal period is synonymous with fiscal year and means the 12-month period ending on March 31 of each year or such other...

  10. 7 CFR 959.16 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Fiscal period. 959.16 Section 959.16 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Regulating Handling Definitions § 959.16 Fiscal period. Fiscal period means the annual period beginning and...

  11. 7 CFR 926.5 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Fiscal period. 926.5 Section 926.5 Agriculture... RECORDKEEPING REQUIREMENTS APPLICABLE TO CRANBERRIES NOT SUBJECT TO THE CRANBERRY MARKETING ORDER § 926.5 Fiscal period. Fiscal period is synonymous with fiscal year and crop year and means the 12-month period...

  12. 7 CFR 956.113 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Fiscal period. 956.113 Section 956.113 Agriculture... VALLEY OF SOUTHEAST WASHINGTON AND NORTHEAST OREGON Rules and Regulations § 956.113 Fiscal period. Pursuant to § 956.13, fiscal period shall mean the period beginning January 1 and ending December 31 of...

  13. 7 CFR 924.7 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Fiscal period. 924.7 Section 924.7 Agriculture... COUNTIES IN WASHINGTON AND IN UMATILLA COUNTY, OREGON Order Regulating Handling Definitions § 924.7 Fiscal period. Fiscal period is synonymous with fiscal year and means the 12-month period ending on March 31 of...

  14. 7 CFR 945.12 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Fiscal period. 945.12 Section 945.12 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Fiscal period. Fiscal period means the period beginning and ending on the dates approved by the Secretary...

  15. 7 CFR 930.107 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Fiscal period. 930.107 Section 930.107 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Miscellaneous Provisions § 930.107 Fiscal period. Pursuant to § 930.7, fiscal period shall mean the period...

  16. 7 CFR 946.9 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Fiscal period. 946.9 Section 946.9 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Order Regulating Handling Definitions § 946.9 Fiscal period. Fiscal period means the period beginning on...

  17. 7 CFR 948.10 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Fiscal period. 948.10 Section 948.10 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Order Regulating Handling Definitions § 948.10 Fiscal period. Fiscal period means the period beginning...

  18. 7 CFR 953.9 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Fiscal period. 953.9 Section 953.9 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... STATES Order Regulating Handling Definitions § 953.9 Fiscal period. Fiscal period means the period...

  19. 7 CFR 917.9 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Fiscal period. 917.9 Section 917.9 Agriculture... CALIFORNIA Order Regulating Handling Definitions § 917.9 Fiscal period. Fiscal period is synonymous with fiscal year and means the 12-month period ending on the last day of February of each year, or such other...

  20. 7 CFR 920.7 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Fiscal period. 920.7 Section 920.7 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Definitions § 920.7 Fiscal period. Fiscal period is synonymous with fiscal year and means a 12-month period...

  1. 7 CFR 958.12 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Fiscal period. 958.12 Section 958.12 Agriculture... COUNTIES IN IDAHO, AND MALHEUR COUNTY, OREGON Order Regulating Handling Definitions § 958.12 Fiscal period. Fiscal period means the period beginning and ending on the dates approved by the Secretary pursuant to...

  2. 7 CFR 929.6 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Fiscal period. 929.6 Section 929.6 Agriculture... LONG ISLAND IN THE STATE OF NEW YORK Order Regulating Handling Definitions § 929.6 Fiscal period. Fiscal period is synonymous with fiscal year and crop year and means the 12-month period beginning...

  3. 7 CFR 922.7 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Fiscal period. 922.7 Section 922.7 Agriculture... IN WASHINGTON Order Regulating Handling Definitions § 922.7 Fiscal period. Fiscal period is synonymous with fiscal year and means the 12-month period ending on March 31 of each year or such other...

  4. 7 CFR 1230.9 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Fiscal period. 1230.9 Section 1230.9 Agriculture... CONSUMER INFORMATION Pork Promotion, Research, and Consumer Information Order Definitions § 1230.9 Fiscal period. Fiscal period means the 12-month period ending on December 31 or such other consecutive 12-month...

  5. 7 CFR 955.13 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Fiscal period. 955.13 Section 955.13 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Definitions § 955.13 Fiscal period. Fiscal period means the 12-month period beginning on September 16 and...

  6. 7 CFR 953.122 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Fiscal period. 953.122 Section 953.122 Agriculture... STATES Rules and Regulations Change in Date for Completing Nominations, Term of Office, and Fiscal Period § 953.122 Fiscal period. The fiscal period, pursuant to § 953.9, which began on April 1, 1976, shall end...

  7. 7 CFR 1218.8 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Fiscal period. 1218.8 Section 1218.8 Agriculture... INFORMATION ORDER Blueberry Promotion, Research, and Information Order Definitions § 1218.8 Fiscal period. Fiscal period means a calendar year from January 1 through December 31, or such other period as approved...

  8. 7 CFR 947.9 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Fiscal period. 947.9 Section 947.9 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Definitions § 947.9 Fiscal period. Fiscal period means the period beginning and ending on the dates approved...

  9. 5 CFR 9901.411 - Appraisal period.

    Science.gov (United States)

    2010-01-01

    ... period, an employee has not met the minimum period of performance, management may extend the appraisal... PERSONNEL SYSTEM (NSPS) Performance Management § 9901.411 Appraisal period. (a) Except as provided in... groups of employees; (2) The appraisal period may begin after October 1 for employees who move to an NSPS...

  10. VARIANT OF PERIODIZATION OF BIOLOGICALLY SIMILAR STAGES OF HUMAN AND RAT’S ONTOGENESIS

    Directory of Open Access Journals (Sweden)

    O.A.Gelashvily

    2008-12-01

    Full Text Available The research was carried outgrowing individuals of white laboratory outbred rats. Proportional age ratio of investigated objects and age periods of human was made. Carrying out morphological research on animals with subsequent transferring these data on human purposely to realize the analysis of features of body systems' formation during prenatal and postnatal periods of ontogenesis is obviously possible.

  11. Period doubling patterns of interval maps

    CERN Document Server

    Valaristos, A

    2003-01-01

    We prove the existence and demonstrate the construction of period doubling patterns centered at periodic orbits of continuous maps on the interval. In particular we prove that f in R: =set membership C sup 0 (I,I) exhibits a period doubling pattern centered at a fixed point of f if and only if the set of periodic points is not closed. Furthermore, we prove that if f has a periodic orbit of period n>1, which is not a power of two, and n .pr. m in Sarkovskii's ordering, then f exhibits a period doubling pattern centered at a periodic orbit of period m. An analytic configuration of such period doubling patterns is exhibited.

  12. Generalized trends in the formation energies of perovskite oxides

    DEFF Research Database (Denmark)

    Zeng, Zhenhua; Calle-Vallejo, Federico; Mogensen, Mogens Bjerg

    2013-01-01

    usually have quite different but ordered formation energies. On the other hand, for a given A-site cation, (III) the formation energies of perovskites vary linearly with respect to the atomic number of the elements at the B site within the same period of the periodic table, and the slopes depend...... contributions of their constituent oxides, the trends can be rationalized in terms of A–O and B–O interactions in the ionic crystal. These findings reveal the existence of general systematic trends in the formation energies of perovskites and provide further insight into the role of ion–ion interactions...

  13. Family Formation and Men's and Women's Attainment of Workplace Authority

    Science.gov (United States)

    Bygren, Magnus; Gahler, Michael

    2012-01-01

    Using Swedish panel data, we assess whether the gender gap in supervisory authority has changed during the period 1968-2000, and investigate to what extent the gap can be attributed to gender-specific consequences of family formation. The results indicate that the gap has narrowed modestly during the period, and that the life-event of parenthood…

  14. 77 FR 5470 - Periodicals-Recognition of Distribution of Periodicals via Electronic Copies

    Science.gov (United States)

    2012-02-03

    ... 111 Periodicals--Recognition of Distribution of Periodicals via Electronic Copies AGENCY: Postal... allow distribution of Periodicals publications through various electronic media channels. According to the standards that govern the Periodicals class, all paid circulation for publications authorized in...

  15. The 'Mamelodi Rondavels' as place in the formative period of Bantu ...

    African Journals Online (AJOL)

    The 'Mamelodi rondavels' have recently been investigated as part of a Municipal ecotourism project to determine their heritage value and conservation potential. The retention of the heritage place, defined by a small group of rondavel style buildings, is important because it exists as significant visual local remnant of the ...

  16. Formation and dynamics of supported phospholipid membranes on a periodic nanotextured substrate

    Energy Technology Data Exchange (ETDEWEB)

    Werner, James H [Los Alamos National Laboratory; Montano, Gabriel M [Los Alamos National Laboratory; Shreve, Andrew P [Los Alamos National Laboratory

    2008-01-01

    We have studied and modeled the morphology and dynamics of planar lipid bilayer assemblies supported on a textured silicon substrate that contains nano-structured features perpendicular to the plane of observation. Using a combination of characterization methods, including atomic force microscopy and quantitative fluorescence microscopy, we have discovered the bilayer assemblies are conformal to the underlying nanostructured substrate. As far as the dynamics are concnerned, the lipids freely diffuse in and out of the plane of observation while supported by the nanotextured material. In a microscopic sense, diffusion is isotropic along the patterned substrate. Macroscopically, when observed over length scales exceeding the dimensions of the nano-structured features, the diffusion appears anisotropic. The observed macroscopic anisotropy is well simulated using models of diffusion on the nanostructured surface that assume the lipids diffuse homogeneously and isotropically on the supporting nanotextured substrate.

  17. The 'Mamelodi Rondavels' as place in the formative period of Bantu ...

    African Journals Online (AJOL)

    The retention of the heritage place, defined by a small group of rondavel style buildings, is important because it exists as significant visual local remnant of the history of Bantu Education and the subsequent struggle for a non-discriminatory, non-racial society. The rondavel complex, the historical core of the now defunct ...

  18. Influence of cosmic radiation on aerosol and cloud formation over short time periods

    DEFF Research Database (Denmark)

    Bondo, Torsten

    This thesis describes a study of Forbush decrease events. These are rapid decreases in the cosmic ray intensity in the Earth’s atmosphere, which are caused by a temporary increased magnetic shielding at Earth due to solar eruptions. The aim is to investigate how these transient ionization phenomena...... for cosmic rays. A list of the ionization change in the troposphere of the strongest Forbush decreases as compared to the ionization change over the solar cycle is calculated and indicates that only a few events induce ionization changes comparable to the solar cycle. Studies of recently available high...

  19. On the formation of elliptic stones due to periodic water waves

    Science.gov (United States)

    Winzer, Klaus

    2013-11-01

    On the beaches of the oceans may be found amongst many stones with irregular shapes also stones that are nearly perfect ellipsoids. In this work, two grinding processes in the surf for stones of ellipsoidal shape are described mathematically on the basis of simple physical models. The first process is the abrasion of material perpendicular to the shortest axis of the stone sliding on the sand of the beach. The model explains the experimental fact that oblong stones with small b/ a-ratios as a rule are slim stones with a small c/ a-ratio. The second process is connected with a rolling motion around the axis of the largest moment of inertia, which leads to an effective grinding on a surface strip perpendicular to the ab-plane. The corresponding calculation yields a criterion for the form stability of the ellipsoid. The obtained result is virtually identical with the experimentally observed maximum of the error distribution function for the b/ a-ratio.

  20. Wavelength dependence of picosecond laser-induced periodic surface structures on copper

    Science.gov (United States)

    Maragkaki, Stella; Derrien, Thibault J.-Y.; Levy, Yoann; Bulgakova, Nadezhda M.; Ostendorf, Andreas; Gurevich, Evgeny L.

    2017-09-01

    The physical mechanisms of the laser-induced periodic surface structures (LIPSS) formation are studied in this paper for single-pulse irradiation regimes. The change in the LIPSS period with wavelength of incident laser radiation is investigated experimentally, using a picosecond laser system, which provides 7-ps pulses in near-IR, visible, and UV spectral ranges. The experimental results are compared with predictions made under the assumption that the surface-scattered waves are involved in the LIPSS formation. Considerable disagreement suggests that hydrodynamic mechanisms can be responsible for the observed pattern periodicity.

  1. Formation of ball lightning

    Energy Technology Data Exchange (ETDEWEB)

    Silberg, P.A. (2833 Lawton Drive, Amarillo, Texas (USA))

    A plasma continuum model for the formation of ball lightning is developed based on a substantial number of reports that the ball is often in the discharge column of a previous lightning stroke. The usual method of setting up the plasma equation for a one-component electron plasma is used. An approximate equation for the plasma is derived from the describing equation which is then solved exactly in terms of the Jacobi elliptic functions. The formation of the ball is based on a nonlinearity of the plasma equation which under certain circumstances permits the field to collapse into a small region. This collapse is interpreted to be ball lightning. The approximate equation derived for the plasma has the same form as a previous equation used to describe the formation of the fireball plasma.

  2. Galaxy formation and evolution

    CERN Document Server

    Mo, Houjun; White, Simon

    2010-01-01

    The rapidly expanding field of galaxy formation lies at the interface between astronomy, particle physics, and cosmology. Covering diverse topics from these disciplines, all of which are needed to understand how galaxies form and evolve, this book is ideal for researchers entering the field. Individual chapters explore the evolution of the Universe as a whole and its particle and radiation content; linear and nonlinear growth of cosmic structure; processes affecting the gaseous and dark matter components of galaxies and their stellar populations; the formation of spiral and elliptical galaxies; central supermassive black holes and the activity associated with them; galaxy interactions; and the intergalactic medium. Emphasizing both observational and theoretical aspects, this book provides a coherent introduction for astronomers, cosmologists, and astroparticle physicists to the broad range of science underlying the formation and evolution of galaxies.

  3. Forces in strategy formation

    DEFF Research Database (Denmark)

    Steensen, Elmer Fly; Sanchez, Ron

    2008-01-01

    literature. Based on an extensive review of relevant theory and empirical work in strategic decision-making, organizational change theory, cognitive and social psychology, and strategy processes, seven kinds of ''forces'' - rational, imposed, teleological, learning, political, heuristic, and social......This chapter proposes that organizational strategy formation should be characterized theoretically as a process that is subject to several interacting forces, rather than represented by separate discrete decisionmodels or theoretic perspectives, as is commonly done in the strategic management...... - are identified as interacting in and having significant influence on the strategy formation process. It is further argued that by applying a holistic ''forces-view'' of the significant and interacting influences on strategy formation, we can better understand the dynamics and challenges in managing the process...

  4. Principles of star formation

    CERN Document Server

    Bodenheimer, Peter H

    2011-01-01

    Understanding star formation is one of the key fields in present-day astrophysics. This book treats a wide variety of the physical processes involved, as well as the main observational discoveries, with key points being discussed in detail. The current star formation in our galaxy is emphasized, because the most detailed observations are available for this case. The book presents a comparison of the various scenarios for star formation, discusses the basic physics underlying each one, and follows in detail the history of a star from its initial state in the interstellar gas to its becoming a condensed object in equilibrium. Both theoretical and observational evidence to support the validity of the general evolutionary path are presented, and methods for comparing the two are emphasized. The author is a recognized expert in calculations of the evolution of protostars, the structure and evolution of disks, and stellar evolution in general. This book will be of value to graduate students in astronomy and astroph...

  5. Control of Ice Formation.

    Science.gov (United States)

    Lo, Ching-Wen; Sahoo, Venkataraman; Lu, Ming-Chang

    2017-03-28

    Ice formation is a catastrophic problem affecting our daily life in a number of ways. At present, deicing methods are costly, inefficient, and environmentally unfriendly. Recently, the use of superhydrophobic surfaces has been suggested as a potential passive anti-icing method. However, no surface is able to repel frost formation at a very cold temperature. In this work, we demonstrated the abilities of spatial control of ice formation and confinement of the ice-stacking direction. The control and confinement were achieved by manipulating the local free energy barrier for frosting. The V-shaped microgroove patterned surface, which possessed these abilities, exhibited the best anti-icing and deicing performances among the studied surfaces. The insight of this study can be applied to alleviate the impact of icing on our daily life and in many industrial systems.

  6. Situated Formative Feedback

    DEFF Research Database (Denmark)

    Lukassen, Niels Bech; Wahl, Christian; Sorensen, Elsebeth Korsgaard

    This study addresses the conceptual challenge of providing students with good quality feedback to enhance student learning in an online community of practice (COP). The aim of the study is to identify feedback mechanisms in a virtual learning environment (VLE) and to create a full formative...... feedback episode (FFE) through an online dialogue. The paper argues that dialogue is crucial for student learning and that feedback is not only something the teacher gives to the student. Viewing good quality feedback as social, situated, formative, emphasis is put on the establishment of dialogue. We...... refer to this type of feedback as, Situated Formative Feedback (SFF). As a basis for exploring, identifying and discussing relevant aspects of SFF the paper analyses qualitative data from a Moodle dialogue. Data are embedded in the qualitative analytic program Nvivo and are analysed with a system...

  7. [Adrenal hemorrhage in perinatal period--a case report].

    Science.gov (United States)

    Zakanj, Zora; Tuckar, Neven

    2014-01-01

    The incidence of adrenal hemorrhage in perinatal period is 0.2-0.5%. Prenatal diagnosis is rare. In most cases, hemorrhage is found during extensive diagnostic workup in a life-threatened or seriously sick newborn. We present a case of a female neonate born at term with suspected cystic intraabdominal mass already in the 32nd week of gestation. After delivery abdominal sonography was done and found an inhomogeneous formation above the upper pole of the right kidney. On magnetic resonance imaging (MR) this formation was described as an expansive lesion in the lodge of the right adrenal gland, measuring 3.8 x 2.8 x 3.5 cm, which corresponded to the bleeding from the adrenal gland. Extensive differential diagnostic evaluation excluded other diseases, especially malignant. From the birth during the perinatal period the child had no clinical manifestation. Regular ultrasound monitoring showed the resolution of the described formation, until its complete disappearance at the age of two months.

  8. Tea aroma formation

    Directory of Open Access Journals (Sweden)

    Chi-Tang Ho

    2015-03-01

    Full Text Available Besides water, tea is one of the most popular beverages around the world. The chemical ingredients and biological activities of tea have been summarized recently. The current review summarizes tea aroma compounds and their formation in green, black, and oolong tea. The flavor of tea can be divided into two categories: taste (non-volatile compounds and aroma (volatile compounds. All of these aroma molecules are generated from carotenoids, lipids, glycosides, etc. precursors, and also from Maillard reaction. In the current review, we focus on the formation mechanism of main aromas during the tea manufacturing process.

  9. Isolating Triggered Star Formation

    Energy Technology Data Exchange (ETDEWEB)

    Barton, Elizabeth J.; Arnold, Jacob A.; /UC, Irvine; Zentner, Andrew R.; /KICP, Chicago /Chicago U., EFI; Bullock, James S.; /UC, Irvine; Wechsler, Risa H.; /KIPAC, Menlo

    2007-09-12

    Galaxy pairs provide a potentially powerful means of studying triggered star formation from galaxy interactions. We use a large cosmological N-body simulation coupled with a well-tested semi-analytic substructure model to demonstrate that the majority of galaxies in close pairs reside within cluster or group-size halos and therefore represent a biased population, poorly suited for direct comparison to 'field' galaxies. Thus, the frequent observation that some types of galaxies in pairs have redder colors than 'field' galaxies is primarily a selection effect. We use our simulations to devise a means to select galaxy pairs that are isolated in their dark matter halos with respect to other massive subhalos (N= 2 halos) and to select a control sample of isolated galaxies (N= 1 halos) for comparison. We then apply these selection criteria to a volume-limited subset of the 2dF Galaxy Redshift Survey with M{sub B,j} {le} -19 and obtain the first clean measure of the typical fraction of galaxies affected by triggered star formation and the average elevation in the star formation rate. We find that 24% (30.5 %) of these L* and sub-L* galaxies in isolated 50 (30) h{sup -1} kpc pairs exhibit star formation that is boosted by a factor of {approx}> 5 above their average past value, while only 10% of isolated galaxies in the control sample show this level of enhancement. Thus, 14% (20 %) of the galaxies in these close pairs show clear triggered star formation. Our orbit models suggest that 12% (16%) of 50 (30) h{sup -1} kpc close pairs that are isolated according to our definition have had a close ({le} 30 h{sup -1} kpc) pass within the last Gyr. Thus, the data are broadly consistent with a scenario in which most or all close passes of isolated pairs result in triggered star formation. The isolation criteria we develop provide a means to constrain star formation and feedback prescriptions in hydrodynamic simulations and a very general method of understanding

  10. The formation of stars

    CERN Document Server

    Stahler, Steven W

    2008-01-01

    This book is a comprehensive treatment of star formation, one of the most active fields of modern astronomy. The reader is guided through the subject in a logically compelling manner. Starting from a general description of stars and interstellar clouds, the authors delineate the earliest phases of stellar evolution. They discuss formation activity not only in the Milky Way, but also in other galaxies, both now and in the remote past. Theory and observation are thoroughly integrated, with the aid of numerous figures and images. In summary, this volume is an invaluable resource, both as a text f

  11. Syntactic Formats for Free

    DEFF Research Database (Denmark)

    Klin, Bartek; Sobocinski, Pawel

    2003-01-01

    A framework of Plotkin and Turi’s, originally aimed at providing an abstract notion of bi-simulation, is modified to cover other operational equivalences and preorders. Combined with bi-algebraic methods, it yields a technique for the derivation of syntactic formats for transition system specific......A framework of Plotkin and Turi’s, originally aimed at providing an abstract notion of bi-simulation, is modified to cover other operational equivalences and preorders. Combined with bi-algebraic methods, it yields a technique for the derivation of syntactic formats for transition system...

  12. Densities and Kinematic Viscosities for the Systems Benzene + Methyl Formate, Benzene + Ethyl Formate, Benzene + Propyl Formate, and Benzene + Butyl Formate

    DEFF Research Database (Denmark)

    Emmerling, Uwe; Rasmussen, Peter

    1998-01-01

    Densities and kinematic viscosities have been measured for the system benzene + methyl formate at 20°C and for the systems benzene + ethyl formate, benzene + propyl formate, and benzene + butyl formate from 20°C to 50°C. The results for the system benzene + methyl formate have been correlated using...... a Redlich-Kister type of expression with temperature-independent parameters and the data for the systems benzene + ethyl formate, benzene + propyl formate, and benzene + butyl formate with temperature-dependent parameters. The viscosities have furthermore been compared to values predicted by means of the GC...

  13. Optimization of culture conditions for Gardnerella vaginalis biofilm formation.

    Science.gov (United States)

    Machado, Daniela; Palmeira-de-Oliveira, Ana; Cerca, Nuno

    2015-11-01

    Bacterial vaginosis is the leading vaginal disorder in women in reproductive age. Although bacterial vaginosis is related with presence of a biofilm composed predominantly by Gardnerella vaginalis, there has not been a detailed information addressing the environmental conditions that influence the biofilm formation of this bacterial species. Here, we evaluated the influence of some common culture conditions on G. vaginalis biofilm formation, namely inoculum concentration, incubation period, feeding conditions and culture medium composition. Our results showed that culture conditions strongly influenced G. vaginalis biofilm formation and that biofilm formation was enhanced when starting the culture with a higher inoculum, using a fed-batch system and supplementing the growth medium with maltose.

  14. Effect of permittivity on periodic nanostructures by femtosecond laser irradiation on Ti plate

    Science.gov (United States)

    Ooga, T.; Tsukamoto, M.; Sato, Y.; Miyake, M.

    2017-02-01

    Titanium (Ti) is widely used as biomaterial, for example artificial bone, joint etcetera. Femtosecond laser can be used to form periodic nanostructures on Ti surface, and the structures help to control cell elongation. The period of the periodic nanostructures on Ti under atmospheric condition is about 70 to 80% compared with the laser wavelength. However, the mechanism of periodic nanostructure formation by femtosecond laser irradiation has not been clarified yet. Thus, we focused on Surface Plasmon Polariton (SPP) model, which was proposed as a model for formation of periodic nanostructures by femtosecond laser irradiation. In this model, standing waves are generated on the material surface caused by excited electrons on the material surface by laser irradiation. The wavelength of the standing waves depends on the permittivity of the surrounding medium, and the period of the periodic nanostructures also depends on the wavelength of the standing waves. Therefore, it is considered that the period of the nanostructures varies by changing the permittivity at the laser irradiation interface2,3).In this study, a polyethylene terephthalate (PET) films which has permittivity of 3.0, and a polymethyl methacrylate (PMMA) films which has permittivity of 3.4 were contacted on Ti surface by using contact jig and then the femtosecond laser at a wavelength of 800 nm was irradiated to create periodic nanostructures. As a result, periodic nanostructures with a period of 440 nm was formed on Ti under PET adhesion condition, and periodic nanostructures with a period of 380 nm was formed on Ti under PMMA adhesion condition. On the other hand, periodic nanostructures with a period of 600 nm was formed on Ti under atmospheric condition. It was found that the period of periodic nanostructures can be controlled by changing the permittivity of the medium adhered to Ti.

  15. Carrascolendas: A Formative Evaluation.

    Science.gov (United States)

    Laosa, Luis M.

    A formative research project sought to test viewer reactions to two pilot programs of the Carrascolendas series. A total of 360 Puerto Rican-American, Cuban-American, Mexican-American, and Anglo-American children in grades 1, 2, and 3 were observed as they watched the programs. Results indicated that there was high eye contact during the…

  16. Generic file format

    Science.gov (United States)

    Felgate, Nick

    2002-11-01

    The Generic File Format (GFF) is a file format developed within the UK ASW community for the interchange and storage of underwater sonar data. Originally developed for the interchange of time-series data between analysis systems, it has been extended to provide for storage of processed acoustic data (e.g., power and DEMON spectrum, lofargram grey-scale), nonacoustic data (e.g., own-ship dynamics, sensor configuration) and event data (e.g., tracker output, sonar intercepts). The format employs the chunk concept, as used in the WAV and AIFF file formats, to provide extendability (including local variants) while providing a measure of backward compatability. However, the basic concept has been adapted to allow for the mixing in the one file of multiple channels of different sample-rates and data-types through the inclusion of a data frame concept and multiple data blocks. Chunk cross-referencing has been employed to ensure data consistency. A provision is made in the header of the file to store details of the sensor and processing for the data (e.g., the number of hydrophones, beam direction, FFT size) so that an analysis system does not need to know about the sensor or other system from which the data originated.

  17. The Formation of Trihalomethanes.

    Science.gov (United States)

    Trussell, R. Rhodes; Umphres, Mark D.

    1978-01-01

    Reviewed are a number of factors important in the formation of trihalomethanes (THM) including the nature of aquatic humus and the influences of preozonation, bromide, pH, and chlorine. A brief investigation is also conducted into the kinetics of the THM reaction. Several major research needs are represented. (CS)

  18. Meningococcal biofilm formation

    DEFF Research Database (Denmark)

    Lappann, M.; Haagensen, Janus Anders Juul; Claus, H.

    2006-01-01

    We show that in a standardized in vitro flow system unencapsulated variants of genetically diverse lineages of Neisseria meningitidis formed biofilms, that could be maintained for more than 96 h. Biofilm cells were resistant to penicillin, but not to rifampin or ciprofloxacin. For some strains, m......X alleles was identified among genetically diverse meningococcal strains. PilX alleles differed in their propensity to support autoaggregation of cells in suspension, but not in their ability to support microcolony formation within biofilms in the continuous flow system......., microcolony formation within biofilms was observed. Microcolony formation in strain MC58 depended on a functional copy of the pilE gene encoding the pilus subunit pilin, and was associated with twitching of cells. Nevertheless, unpiliated pilE mutants formed biofilms showing that attachment and accumulation...... of cells did not depend on pilus expression. Mutation and complementation analysis revealed that the type IV pilus-associated protein PilX, which was recently shown to mediate interbacterial aggregation, indirectly supported microcolony formation by contributing to pilus expression. A large number of Pil...

  19. Pattern formation today.

    Science.gov (United States)

    Chuong, Cheng-Ming; Richardson, Michael K

    2009-01-01

    Patterns are orders embedded in randomness. They may appear as spatial arrangements or temporal series, and the elements may appear identical or with variations. Patterns exist in the physical world as well as in living systems. In the biological world, patterns can range from simple to complex, forming the basic building blocks of life. The process which generates this ordering in the biological world was termed pattern formation. Since Wolpert promoted this concept four decades ago, scientists from molecular biology, developmental biology, stem cell biology, tissue engineering, theoretical modeling and other disciplines have made remarkable progress towards understanding its mechanisms. It is time to review and re-integrate our understanding. Here, we explore the origin of pattern formation, how the genetic code is translated into biological form, and how complex phenotypes are selected over evolutionary time. We present four topics: Principles, Evolution, Development, and Stem Cells and Regeneration. We have interviewed several leaders in the field to gain insight into how their research and the field of pattern formation have shaped each other. We have learned that both molecular process and physico-chemical principles are important for biological pattern formation. New understanding will emerge through integration of the analytical approach of molecular-genetic manipulation and the systemic approach of model simulation. We regret that we could not include every major investigator in the field, but hope that this Special Issue of the Int. J. Dev. Biol. represents a sample of our knowledge of pattern formation today, which will help to stimulate more research on this fundamental process.

  20. Periodic current oscillations of zinc in nitric acid solutions

    Directory of Open Access Journals (Sweden)

    ERVIN SALLÓ

    2008-02-01

    Full Text Available The charge percolation mechanism (CPM of olefin polymerization in the presence of transition metal compounds has been applied to explain the polymerization of ethylene by silica supported chromium oxide. In the previous work of this series, the fundamental issues and mechanism of this polymerization were presented. In this work the compatibility of the CPM with the empirical findings is confirmed. The CPM has been applied to explain: the appearance of an induction period; the deactivation of active centers and the formation of oligomers; the effects of chromium concentration on the silica surface, the silica surface discontinuity and the pore size of silica on polymerization and the formation of the structure of polyethylene. A mathematical model has been derived to explain the effects of the CrOx/SiO2 ratio on the productivity of Phillips catalysts in the polymerization of ethylene. The empirical findings have also been confirmed by computer simulations.

  1. Periodic Solution of the Hematopoiesis Equation

    Directory of Open Access Journals (Sweden)

    Ji-Huan He

    2013-01-01

    Full Text Available Wu and Liu (2012 presented some results for the existence and uniqueness of the periodic solutions for the hematopoiesis model. This paper gives a simple approach to find an approximate period of the model.

  2. Periodic Poisson model for beam dynamics simulation

    Directory of Open Access Journals (Sweden)

    M. Dohlus

    2016-03-01

    Full Text Available A method is described to solve the Poisson problem for a three dimensional source distribution that is periodic into one direction. Perpendicular to the direction of periodicity a free space (or open boundary condition is realized. In beam physics, this approach allows us to calculate the space charge field of a continualized charged particle distribution with periodic pattern. The method is based on a particle-mesh approach with equidistant grid and fast convolution with a Green’s function. The periodic approach uses only one period of the source distribution, but a periodic extension of the Green’s function. The approach is numerically efficient and allows the investigation of periodic- and pseudoperiodic structures with period lengths that are small compared to the source dimensions, for instance of laser modulated beams or of the evolution of micro bunch structures. Applications for laser modulated beams are given.

  3. Periodic Control of Power Electronic Converters

    DEFF Research Database (Denmark)

    Zhou, Keliang; Danwei, Wang; Yang, Yongheng

    Advanced power electronic converters convert, control and condition electricity. Power converters require control strategies for periodic signal compensation to assure good power quality and stable power system operation. This comprehensive text presents the most recent internal model principle...... based periodic control technology, which offers the perfect periodic control solution for power electronic conversion. It also provides complete analysis and synthesis methods for periodic control systems, and plenty of practical examples to demonstrate the validity of proposed periodic control...... technology for power converters. It proposes a unified framework for housing periodic control schemes for power converters, and provides a general proportional-integral-derivative control solution to periodic signal compensation in extensive engineering applications. Periodic Control of Power Electronic...

  4. On a quasi-periodic Hopf bifurcation

    NARCIS (Netherlands)

    Braaksma, B.L.J.; Broer, H.W.

    1987-01-01

    In this paper we study quasi-periodic Hopf bifurcations for the model problem of a quasi-periodically forced oscillator, where the frequencies remain fixed. For this purpose we first consider Stoker's problem for small damping.

  5. Periodic solutions of nonlinear vibrating beams

    Directory of Open Access Journals (Sweden)

    J. Berkovits

    2003-01-01

    Full Text Available The aim of this paper is to prove new existence and multiplicity results for periodic semilinear beam equation with a nonlinear time-independent perturbation in case the period is not prescribed. Since the spectrum of the linear part varies with the period, the solvability of the equation depends crucially on the period which can be chosen as a free parameter. Since the period of the external forcing is generally unknown a priori, we consider the following natural problem. For a given time-independent nonlinearity, find periods T for which the equation is solvable for any T-periodic forcing. We will also deal with the existence of multiple solutions when the nonlinearity interacts with the spectrum of the linear part. We show that under certain conditions multiple solutions do exist for any small forcing term with suitable period T. The results are obtained via generalized Leray-Schauder degree and reductions to invariant subspaces.

  6. The Middle Islamic and Crusader Periods

    DEFF Research Database (Denmark)

    Walmsley, Alan George

    2008-01-01

    The book chapter presents a critical review of the archaeology of Jordan in the middle Islamic periods (8th - 17th centuries CE), presenting a new evaluation of settlement and culture in the period, and assesses the errors of past appraoches.......The book chapter presents a critical review of the archaeology of Jordan in the middle Islamic periods (8th - 17th centuries CE), presenting a new evaluation of settlement and culture in the period, and assesses the errors of past appraoches....

  7. Ramanujan subspace pursuit for signal periodic decomposition

    Science.gov (United States)

    Deng, Shi-Wen; Han, Ji-Qing

    2017-06-01

    The period estimation and periodic decomposition of a signal represent long-standing problems in the field of signal processing and biomolecular sequence analysis. To address such problems, we introduce the Ramanujan subspace pursuit (RSP) based on the Ramanujan subspace. As a greedy iterative algorithm, the RSP can uniquely decompose any signal into a sum of exactly periodic components by selecting and removing the most dominant periodic component from the residual signal in each iteration. In the RSP, a novel periodicity metric is derived based on the energy of the exactly periodic component obtained by orthogonally projecting the residual signal into the Ramanujan subspace. The metric is then used to select the most dominant periodic component in each iteration. To reduce the computational cost of the RSP, we also propose the fast RSP (FRSP) based on the relationship between the periodic subspace and the Ramanujan subspace and based on the maximum likelihood estimation of the energy of the periodic component in the periodic subspace. The fast RSP has a lower computational cost and can decompose a signal of length N into a sum of K exactly periodic components in O (KNlogN) . In short, the main contributions of this paper are threefold: First, we present the RSP algorithm for decomposing a signal into its periodic components and theoretically prove the convergence of the algorithm based on the Ramanujan subspaces. Second, we present the FRSP algorithm, which is used to reduce the computational cost. Finally, we derive a periodic metric to measure the periodicity of the hidden periodic components of a signal. In addition, our results show that the RSP outperforms current algorithms for period estimation.

  8. 75 FR 47717 - Content of Periodicals Mail

    Science.gov (United States)

    2010-08-09

    ... Part 111 Content of Periodicals Mail AGENCY: Postal Service\\TM\\ ACTION: Final rule; revised. SUMMARY... Manual (DMM ) 707.3, to update ``content requirements'' on materials eligible for mailing at Periodicals prices with authorized Periodicals publications. DATES: Effective Date: August 9, 2010. FOR FURTHER...

  9. 7 CFR 1206.7 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Fiscal period. 1206.7 Section 1206.7 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS... INFORMATION Mango Promotion, Research, and Information Order Definitions § 1206.7 Fiscal period. Fiscal period...

  10. 7 CFR 1150.107 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Fiscal period. 1150.107 Section 1150.107 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Order Definitions § 1150.107 Fiscal period. Fiscal period means the calendar year or such other annual...

  11. 7 CFR 925.112 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Fiscal period. 925.112 Section 925.112 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... SOUTHEASTERN CALIFORNIA Rules and Regulations § 925.112 Fiscal period. Beginning January 1, 1988, fiscal period...

  12. 7 CFR 947.114 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Fiscal period. 947.114 Section 947.114 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Definitions § 947.114 Fiscal period. The fiscal period shall begin July 1 of each year and end June 30 of the...

  13. 7 CFR 906.15 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Fiscal period. 906.15 Section 906.15 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... RIO GRANDE VALLEY IN TEXAS Order Regulating Handling Definitions § 906.15 Fiscal period. Fiscal period...

  14. 7 CFR 916.7 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Fiscal period. 916.7 Section 916.7 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Regulating Handling Definitions § 916.7 Fiscal period. Fiscal period is synonymous with fiscal year and means...

  15. 7 CFR 1205.307 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Fiscal period. 1205.307 Section 1205.307 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS... Research and Promotion Order Definitions § 1205.307 Fiscal period. Fiscal period is the 12-month budgetary...

  16. 7 CFR 905.11 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Fiscal period. 905.11 Section 905.11 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... TANGELOS GROWN IN FLORIDA Order Regulating Handling Definitions § 905.11 Fiscal period. Fiscal period means...

  17. 7 CFR 959.104 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Fiscal period. 959.104 Section 959.104 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Regulations General § 959.104 Fiscal period. The fiscal period shall begin August 1 of each year and end July...

  18. 7 CFR 925.12 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Fiscal period. 925.12 Section 925.12 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... SOUTHEASTERN CALIFORNIA Definitions § 925.12 Fiscal period. Fiscal period is synonymous with fiscal year and...

  19. 7 CFR 1250.303 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Fiscal period. 1250.303 Section 1250.303 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS... Research and Promotion Order Definitions § 1250.303 Fiscal period. Fiscal period means the calendar year...

  20. 7 CFR 1212.7 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Fiscal period. 1212.7 Section 1212.7 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS..., Consumer Education, and Industry Information Order Definitions § 1212.7 Fiscal period. “Fiscal period...

  1. 7 CFR 945.111 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Fiscal period. 945.111 Section 945.111 Agriculture... DESIGNATED COUNTIES IN IDAHO, AND MALHEUR COUNTY, OREGON Rules and Regulations Definitions § 945.111 Fiscal period. The fiscal period that began June 1, 1981, shall end July 31, 1982. Each year thereafter fiscal...

  2. 7 CFR 956.13 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Fiscal period. 956.13 Section 956.13 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... VALLEY OF SOUTHEAST WASHINGTON AND NORTHEAST OREGON Definitions § 956.13 Fiscal period. Fiscal period...

  3. Estimated Incubation Period for Zika Virus Disease.

    Science.gov (United States)

    Krow-Lucal, Elisabeth R; Biggerstaff, Brad J; Staples, J Erin

    2017-05-01

    Information about the Zika virus disease incubation period can help identify risk periods and local virus transmission. In 2015-2016, data from 197 symptomatic travelers with recent Zika virus infection indicated an estimated incubation period of 3-14 days. For symptomatic persons with symptoms >2 weeks after travel, transmission might be not travel associated.

  4. 38 CFR 21.4204 - Periodic certifications.

    Science.gov (United States)

    2010-07-01

    ... (CONTINUED) VOCATIONAL REHABILITATION AND EDUCATION Administration of Educational Assistance Programs Schools... on the following items when applicable: (1) Continued enrollment in and pursuit of the course. (2... periodic certifications will show any vacation period or interval between periods of instruction as...

  5. 5 CFR 316.304 - Trial period.

    Science.gov (United States)

    2010-01-01

    ... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Trial period. 316.304 Section 316.304... Term Employment § 316.304 Trial period. (a) The first year of service of a term employee is a trial... completion of the required trial period in the same manner as prescribed by § 315.802 of this chapter. (b...

  6. 14 CFR 325.6 - Periodic reviews.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Periodic reviews. 325.6 Section 325.6... REGULATIONS ESSENTIAL AIR SERVICE PROCEDURES § 325.6 Periodic reviews. (a) The Department will start a periodic review of essential air service within 1 year of the date of the previous determination of...

  7. 32 CFR 552.80 - Suspension period.

    Science.gov (United States)

    2010-07-01

    ... 32 National Defense 3 2010-07-01 2010-07-01 true Suspension period. 552.80 Section 552.80 National... Suspension period. All solicitation privileges suspended by installation commanders will be for a specific time. Normally, it will not exceed 2 years. When the suspension period expires, the agent may reapply...

  8. 49 CFR 236.588 - Periodic test.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Periodic test. 236.588 Section 236.588..., Train Control and Cab Signal Systems Inspection and Tests; Locomotive § 236.588 Periodic test. Except as provided in § 236.586, periodic test of the automatic train stop, train control, or cab signal apparatus...

  9. Measuring Stellar Rotation Periods with Kepler

    DEFF Research Database (Denmark)

    Nielsen, M. B.; Gizon, L.; Schunker, H.

    2013-01-01

    We measure rotation periods for 12151 stars in the Kepler field, based on photometric variability caused by stellar activity. Our analysis returns stable rotation periods over at least six out of eight quarters of Kepler data. This large sample of stars enables us to study rotation periods...

  10. MODELLING OF THE PROCESS OF TEACHING READING ENGLISH LANGUAGE PERIODICALS

    Directory of Open Access Journals (Sweden)

    Тетяна Глушко

    2014-07-01

    Full Text Available The article reveals a scientifically substantiated process of teaching reading English language periodicals in all its components, which are consistently developed, and form of interconnection of the structural elements in the process of teaching reading. This process is presented as a few interconnected and interdetermined models: 1 the models of the process of acquiring standard and expressive lexical knowledge; 2 the models of the process of formation of skills to use such vocabulary; 3 the models of the development of skills to read texts of the different linguistic levels.

  11. Evolution of full phononic band gaps in periodic cellular structures

    Science.gov (United States)

    Wormser, Maximilian; Warmuth, Franziska; Körner, Carolin

    2017-10-01

    Cellular materials not only show interesting static properties, but can also be used to manipulate dynamic mechanical waves. In this contribution, the existence of phononic band gaps in periodic cellular structures is experimentally shown via sonic transmission experiment. Cellular structures with varying numbers of cells are excited by piezoceramic actuators and the transmitted waves are measured by piezoceramic sensors. The minimum number of cells necessary to form a clear band gap is determined. A rotation of the cells does not have an influence on the formation of the gap, indicating a complete phononic band gap. The experimental results are in good agreement with the numerically obtained dispersion relation.

  12. Formation of multiple networks

    DEFF Research Database (Denmark)

    Magnani, Matteo; Rossi, Luca

    2013-01-01

    While most research in Social Network Analysis has focused on single networks, the availability of complex on-line data about individuals and their mutual heterogenous connections has recently determined a renewed interest in multi-layer network analysis. To the best of our knowledge, in this paper...... we introduce the first network formation model for multiple networks. Network formation models are among the most popular tools in traditional network studies, because of both their practical and theoretical impact. However, existing models are not sufficient to describe the generation of multiple...... networks. Our model, motivated by an empirical analysis of real multi-layered network data, is a conservative extension of single-network models and emphasizes the additional level of complexity that we experience when we move from a single- to a more complete and realistic multi-network context....

  13. Handgun waiting periods reduce gun deaths.

    Science.gov (United States)

    Luca, Michael; Malhotra, Deepak; Poliquin, Christopher

    2017-11-14

    Handgun waiting periods are laws that impose a delay between the initiation of a purchase and final acquisition of a firearm. We show that waiting periods, which create a "cooling off" period among buyers, significantly reduce the incidence of gun violence. We estimate the impact of waiting periods on gun deaths, exploiting all changes to state-level policies in the Unites States since 1970. We find that waiting periods reduce gun homicides by roughly 17%. We provide further support for the causal impact of waiting periods on homicides by exploiting a natural experiment resulting from a federal law in 1994 that imposed a temporary waiting period on a subset of states. Copyright © 2017 the Author(s). Published by PNAS.

  14. A highly specific test for periodicity

    Energy Technology Data Exchange (ETDEWEB)

    Ansmann, Gerrit, E-mail: gansmann@uni-bonn.de [Department of Epileptology, University of Bonn, Sigmund-Freud-Straße 25, 53105 Bonn (Germany); Helmholtz Institute for Radiation and Nuclear Physics, University of Bonn, Nussallee 14–16, 53115 Bonn (Germany); Interdisciplinary Center for Complex Systems, University of Bonn, Brühler Straße 7, 53175 Bonn (Germany)

    2015-11-15

    We present a method that allows to distinguish between nearly periodic and strictly periodic time series. To this purpose, we employ a conservative criterion for periodicity, namely, that the time series can be interpolated by a periodic function whose local extrema are also present in the time series. Our method is intended for the analysis of time series generated by deterministic time-continuous dynamical systems, where it can help telling periodic dynamics from chaotic or transient ones. We empirically investigate our method's performance and compare it to an approach based on marker events (or Poincaré sections). We demonstrate that our method is capable of detecting small deviations from periodicity and outperforms the marker-event-based approach in typical situations. Our method requires no adjustment of parameters to the individual time series, yields the period length with a precision that exceeds the sampling rate, and its runtime grows asymptotically linear with the length of the time series.

  15. Determinants for gallstone formation

    DEFF Research Database (Denmark)

    Shabanzadeh, Daniel Monsted; Sorensen, Lars Tue; Jørgensen, Torben

    2016-01-01

    associations were found for blood pressure, smoking, alcohol consumption, HDL cholesterol, or triglycerides in meta-analyses. Conclusions: Age, female sex, BMI, non-HDL cholesterol, and polyps are independent determinants for gallstone formation. Incident gallstones and the metabolic syndrome share common risk....... Gallstone incidence was assessed through repeated ultrasound examinations. Body mass index (BMI), blood pressure, self-rated health, lifestyle variables, blood lipids, and use of female sex hormones were measured at the baseline examination. Statistical analyses included logistic regression. Based...

  16. Formate-assisted pyrolysis

    Science.gov (United States)

    DeSisto, William Joseph; Wheeler, Marshall Clayton; van Heiningen, Adriaan R. P.

    2015-03-17

    The present invention provides, among other thing, methods for creating significantly deoxygenated bio-oils form biomass including the steps of providing a feedstock, associating the feedstock with an alkali formate to form a treated feedstock, dewatering the treated feedstock, heating the dewatered treated feedstock to form a vapor product, and condensing the vapor product to form a pyrolysis oil, wherein the pyrolysis oil contains less than 30% oxygen by weight.

  17. Mars’ peculiar formation

    Science.gov (United States)

    Woo, Man Yin; Brasser, Ramon; Mojzsis, Stephen; Matsumura, Soko; Ida, Shigeru

    2017-10-01

    The formation of the terrestrial planets is a long standing problem. Mars probably holds the key to solving this mystery because of the substantial amount of data gathered from space missions, martian meteorites and its obvious differences when compared to Earth. Recent elemental and isotopic abundances suggest that Mars’ composition is significantly different from that of Earth. Therefore, Mars should have accreted most of its mass in a region different from Earth’s, most likely further from the Sun. These compositional differences should be explained with planet formation models. We tested the probability of producing a Mars analogue that is compositionally different from Earth in two popular planet formation models: the Grand Tack model with tack locations of 1.5 or 2 AU for Jupiter; and the Classical model in which all the terrestrial planets formed near their current locations. We performed a high number of N-body simulations with initial conditions that are either equal-mass planetary embryos or a semi-analytical approach to oligarch growth. Our results show that the probability of producing a Mars analogue which matches the current mass and orbit of Mars is at most 9% but reduces to mostly about 1% when it mainly accretes its mass further than Mars’ current position of 1.5 AU. Strangely enough, in the Grand Tack model the number of Mars analogues produced is independent of the initial number of planet embryos. Hence, we conclude that both planet formation models have difficulties to explain the observed compositional differences between Earth and Mars.

  18. Formation of stellar clusters

    Science.gov (United States)

    Smilgys, Romas; Bonnell, Ian A.

    2017-12-01

    We investigate the triggering of star formation and the formation of stellar clusters in molecular clouds which form as the interstellar medium passes through spiral shocks. The spiral shock compresses gas into an ∼100 pc long main star formation ridge, where clusters form every 5-10 pc along the merger ridge. We use a gravitational potential-based cluster finding algorithm, which extracts individual clusters, calculates their physical properties and traces cluster evolution over multiple time-steps. Final cluster masses at the end of simulation range between 1000 and 30 000 M⊙ with their characteristic half-mass radii between 0.1 and 2 pc. These clusters form by gathering material from 10-20 pc size scales. Clusters also show a mass-specific angular momentum relation, where more massive clusters have larger specific angular momentum due to the larger size scales, and hence angular momentum from which they gather their mass. The evolution shows that more massive clusters experience hierarchical merging process, which increases stellar age spreads up to 2-3 Myr. Less massive clusters appear to grow by gathering nearby recently formed sinks, while more massive clusters with their large global gravitational potentials are increasing their mass growth from gas accretion.

  19. Terrestrial planet formation.

    Science.gov (United States)

    Righter, K; O'Brien, D P

    2011-11-29

    Advances in our understanding of terrestrial planet formation have come from a multidisciplinary approach. Studies of the ages and compositions of primitive meteorites with compositions similar to the Sun have helped to constrain the nature of the building blocks of planets. This information helps to guide numerical models for the three stages of planet formation from dust to planetesimals (~10(6) y), followed by planetesimals to embryos (lunar to Mars-sized objects; few 10(6) y), and finally embryos to planets (10(7)-10(8) y). Defining the role of turbulence in the early nebula is a key to understanding the growth of solids larger than meter size. The initiation of runaway growth of embryos from planetesimals ultimately leads to the growth of large terrestrial planets via large impacts. Dynamical models can produce inner Solar System configurations that closely resemble our Solar System, especially when the orbital effects of large planets (Jupiter and Saturn) and damping mechanisms, such as gas drag, are included. Experimental studies of terrestrial planet interiors provide additional constraints on the conditions of differentiation and, therefore, origin. A more complete understanding of terrestrial planet formation might be possible via a combination of chemical and physical modeling, as well as obtaining samples and new geophysical data from other planets (Venus, Mars, or Mercury) and asteroids.

  20. Infantile amnesia reflects a developmental critical period for hippocampal learning.

    Science.gov (United States)

    Travaglia, Alessio; Bisaz, Reto; Sweet, Eric S; Blitzer, Robert D; Alberini, Cristina M

    2016-09-01

    Episodic memories formed during the first postnatal period are rapidly forgotten, a phenomenon known as 'infantile amnesia'. In spite of this memory loss, early experiences influence adult behavior, raising the question of which mechanisms underlie infantile memories and amnesia. Here we show that in rats an experience learned during the infantile amnesia period is stored as a latent memory trace for a long time; indeed, a later reminder reinstates a robust, context-specific and long-lasting memory. The formation and storage of this latent memory requires the hippocampus, follows a sharp temporal boundary and occurs through mechanisms typical of developmental critical periods, including the expression switch of the NMDA receptor subunits from 2B to 2A, which is dependent on brain-derived neurotrophic factor (BDNF) and metabotropic glutamate receptor 5 (mGluR5). Activating BDNF or mGluR5 after training rescues the infantile amnesia. Thus, early episodic memories are not lost but remain stored long term. These data suggest that the hippocampus undergoes a developmental critical period to become functionally competent.

  1. Seismic isolation of two dimensional periodic foundations

    Energy Technology Data Exchange (ETDEWEB)

    Yan, Y.; Mo, Y. L., E-mail: yilungmo@central.uh.edu [University of Houston, Houston, Texas 77004 (United States); Laskar, A. [Indian Institute of Technology Bombay, Powai, Mumbai (India); Cheng, Z.; Shi, Z. [Beijing Jiaotong University, Beijing (China); Menq, F. [University of Texas, Austin, Texas 78712 (United States); Tang, Y. [Argonne National Laboratory, Argonne, Illinois 60439 (United States)

    2014-07-28

    Phononic crystal is now used to control acoustic waves. When the crystal goes to a larger scale, it is called periodic structure. The band gaps of the periodic structure can be reduced to range from 0.5 Hz to 50 Hz. Therefore, the periodic structure has potential applications in seismic wave reflection. In civil engineering, the periodic structure can be served as the foundation of upper structure. This type of foundation consisting of periodic structure is called periodic foundation. When the frequency of seismic waves falls into the band gaps of the periodic foundation, the seismic wave can be blocked. Field experiments of a scaled two dimensional (2D) periodic foundation with an upper structure were conducted to verify the band gap effects. Test results showed the 2D periodic foundation can effectively reduce the response of the upper structure for excitations with frequencies within the frequency band gaps. When the experimental and the finite element analysis results are compared, they agree well with each other, indicating that 2D periodic foundation is a feasible way of reducing seismic vibrations.

  2. Probabilistic stellar rotation periods with Gaussian processes

    Science.gov (United States)

    Angus, Ruth; Aigrain, Suzanne; Foreman-Mackey, Daniel

    2015-08-01

    Stellar rotation has many applications in the field of exoplanets. High-precision photometry from space-based missions like Kepler and K2 allows us to measure stellar rotation periods directly from light curves. Stellar variability produced by rotation is usually not sinusoidal or perfectly periodic, therefore sine-fitting periodograms are not well suited to rotation period measurement. Autocorrelation functions are often used to extract periodic information from light curves, however uncertainties on rotation periods measured by autocorrelation are difficult to define. A ‘by eye’ check, or a set of heuristic criteria are used to validate measurements and rotation periods are only reported for stars that pass this vetting process. A probabilistic rotation period measurement method, with a suitable generative model bypasses the need for a validation stage and can produce realistic uncertainties. The physics driving the production of variability in stellar light curves is still poorly understood and difficult to model. We therefore use an effective model for stellar variability: a Gaussian process with a quasi-periodic covariance function. By injecting fake signals into Kepler light curves we show that the GP model is well suited to quasi-periodic, non-sinusoidal signals, is capable of modelling noise and physical signals simultaneously and provides probabilistic rotation period measurements with realistic uncertainties.

  3. Optical Periodicity Analysis of 3C 446 using Period04 Fei Guo ...

    Indian Academy of Sciences (India)

    a very convenient interactive interface to fit periodically. We collected the ... the frequency as shown in Table 1 to calculate the period. We got the period ... Optical Periodicity Analysis of 3C 446 using Period04. 287. Table 1. Results in 8, 4.8, 14 and 22 GHz of 3C446. Wave. Frequency (c/d) Amplitude (mag). S/N. Period (yr).

  4. How Do Earth-Sized, Short-Period Planets Form?

    Science.gov (United States)

    Kohler, Susanna

    2017-08-01

    day)23 hot Jupiters (larger than 4 times Earths radius and orbital period shorter than 10 days)243 small hot planets (smaller than 4 times Earths radius and orbital period between 1 and 10 days)They then compare the metallicity distributions of these three groups.Back to the Drawing BoardMetallicity distributions of the three statistical samples. The hot-Jupiter hosts (orange) have different distribution than the others; it is weighted more toward higher metallicities. [Winn et al. 2017]Winn and collaborators find that hosts of ultra-short-period planets do not have the same metallicity distribution as hot-Jupiter hosts; the metallicities of hot-Jupiter hosts are significantly higher. The metallicity distributions for hosts of ultra-short-period planets and hosts of small hot planets were statistically indistinguishable, however.These results strongly suggest that the majority of ultra-short-period planets are not the cores of former hot Jupiters. Alternative options include the possibility that they are the cores of smaller planets, such as sub-Neptunes, or that they are the short-period extension of the distribution of close-in, small rocky planets that formed by core accretion.This narrowing of the options for the formation of ultra-short-period planets is certainly intriguing. We can hope to further explore possibilities in the future after the Transiting Exoplanet Survey Satellites (TESS) comes online next year; TESS is expected to discover many more ultra-short-period planets that are too faint for Kepler to detect.CitationJoshua N. Winn et al 2017 AJ 154 60. doi:10.3847/1538-3881/aa7b7c

  5. Implementing Dust Shielding as a Criteria for Star Formation

    Science.gov (United States)

    Byrne, Lindsey; Christensen, Charlotte

    2018-01-01

    Star formation is observed to occur in dense regions of molecular gas. Although the exact nature of the link between star formation and molecular hydrogen is still unclear, it has been suggested that dust shielding of dense gas is the key factor enabling the presence of both. We present a model in which star formation is linked explicitly to local dust shielding, rather than molecular hydrogen abundance, in smoothed particle hydrodynamics galaxy formation simulations. We used simulations of isolated Milky-Way-mass disk galaxies to develop a dust shielding model in which the radiative shielding length was based off of the Jeans length with a T=40 K temperature cap. Using this shielding model, we compare the effects of different star formation recipes, including recipes in which star formation is based on the amount of dust shielding or the local molecular hydrogen abundance. We test our star formation models on two sets of isolated disk galaxies with solar and sub-solar metallicities and on a cosmological dwarf galaxy simulation. We find that the shielding-based model can reproduce the observed transition from atomic to molecular hydrogen at realistic surface densities, exhibits periodic bursts of star formation, and allows for star formation at higher temperatures and lower densities than a model in which star formation is tied directly to H2 abundance.

  6. Incongruity between Prion Conversion and Incubation Period following Coinfection

    Science.gov (United States)

    Langenfeld, Katie A.; Shikiya, Ronald A.; Kincaid, Anthony E.

    2016-01-01

    ABSTRACT When multiple prion strains are inoculated into the same host, they can interfere with each other. Strains with long incubation periods can suppress conversion of strains with short incubation periods; however, nothing is known about the conversion of the long-incubation-period strain during strain interference. To investigate this, we inoculated hamsters in the sciatic nerve with long-incubation-period strain 139H prior to superinfection with the short-incubation-period hyper (HY) strain of transmissible mink encephalopathy (TME). First, we found that 139H is transported along the same neuroanatomical tracks as HY TME, adding to the growing body of evidence indicating that PrPSc favors retrograde transneuronal transport. In contrast to a previous report, we found that 139H interferes with HY TME infection, which is likely due to both strains targeting the same population of neurons following sciatic nerve inoculation. Under conditions where 139H blocked HY TME from causing disease, the strain-specific properties of PrPSc corresponded with the strain that caused disease, consistent with our previous findings. In the groups of animals where incubation periods were not altered, we found that the animals contained a mixture of 139H and HY TME PrPSc. This finding expands the definition of strain interference to include conditions where PrPSc formation is altered yet disease outcome is unaltered. Overall, these results contradict the premise that prion strains are static entities and instead suggest that strain mixtures are dynamic regardless of incubation period or clinical outcome of disease. IMPORTANCE Prions can exist as a mixture of strains in naturally infected animals, where they are able to interfere with the conversion of each other and to extend incubation periods. Little is known, however, about the dynamics of strain conversion under conditions where incubation periods are not affected. We found that inoculation of the same animal with two strains

  7. Formation of asteroid pairs by rotational fission.

    Science.gov (United States)

    Pravec, P; Vokrouhlický, D; Polishook, D; Scheeres, D J; Harris, A W; Galád, A; Vaduvescu, O; Pozo, F; Barr, A; Longa, P; Vachier, F; Colas, F; Pray, D P; Pollock, J; Reichart, D; Ivarsen, K; Haislip, J; Lacluyze, A; Kusnirák, P; Henych, T; Marchis, F; Macomber, B; Jacobson, S A; Krugly, Yu N; Sergeev, A V; Leroy, A

    2010-08-26

    Pairs of asteroids sharing similar heliocentric orbits, but not bound together, were found recently. Backward integrations of their orbits indicated that they separated gently with low relative velocities, but did not provide additional insight into their formation mechanism. A previously hypothesized rotational fission process may explain their formation-critical predictions are that the mass ratios are less than about 0.2 and, as the mass ratio approaches this upper limit, the spin period of the larger body becomes long. Here we report photometric observations of a sample of asteroid pairs, revealing that the primaries of pairs with mass ratios much less than 0.2 rotate rapidly, near their critical fission frequency. As the mass ratio approaches 0.2, the primary period grows long. This occurs as the total energy of the system approaches zero, requiring the asteroid pair to extract an increasing fraction of energy from the primary's spin in order to escape. We do not find asteroid pairs with mass ratios larger than 0.2. Rotationally fissioned systems beyond this limit have insufficient energy to disrupt. We conclude that asteroid pairs are formed by the rotational fission of a parent asteroid into a proto-binary system, which subsequently disrupts under its own internal system dynamics soon after formation.

  8. Multi-Period Trading via Convex Optimization

    DEFF Research Database (Denmark)

    Boyd, Stephen; Busseti, Enzo; Diamond, Steve

    2017-01-01

    We consider a basic model of multi-period trading, which can be used to evaluate the performance of a trading strategy. We describe a framework for single-period optimization, where the trades in each period are found by solving a convex optimization problem that trades off expected return, risk......, transaction cost and holding cost such as the borrowing cost for shorting assets. We then describe a multi-period version of the trading method, where optimization is used to plan a sequence of trades, with only the first one executed, using estimates of future quantities that are unknown when the trades...

  9. Periodic Continuing Disability Review Case Backlog

    Data.gov (United States)

    Social Security Administration — The Social Security Administration (SSA) conducts periodic CDRs to ensure that only those beneficiaries who remain disabled continue to receive monthly benefits. The...

  10. Periodic Traveling Waves in Diatomic Granular Chains

    Science.gov (United States)

    Betti, Matthew; Pelinovsky, Dmitry E.

    2013-10-01

    We study bifurcations of periodic traveling waves in diatomic granular chains from the anti-continuum limit, when the mass ratio between the light and heavy beads is zero. We show that every limiting periodic wave is uniquely continued with respect to the mass ratio parameter, and the periodic waves with a wavelength larger than a certain critical value are spectrally stable. Numerical computations are developed to study how this solution family is continued to the limit of equal mass ratio between the beads, where periodic traveling waves of homogeneous granular chains exist.

  11. Doppler effects on periodicities in Saturn's magnetosphere

    Science.gov (United States)

    Carbary, J. F.

    2015-11-01

    The magnetosphere of Saturn exhibits a wide variety of periodic phenomena in magnetic fields, charged particles, and radio emissions. The periodicities are observed from a moving spacecraft, so an issue arises about the periodicities being influenced by the Doppler effects. Doppler effects can be investigated using models of the periodicities and then flying the spacecraft through the model, effectively measuring any Doppler phenomena with the simulation. Using 200 days of typical elliptical orbits from the Cassini mission at Saturn, three models were tested: an azimuthal wave (or "searchlight") model, a radial wave (or "pond ripple") model, and a model of an outwardly traveling spiral wave. The azimuthal wave model produced virtually no Doppler effects in the periodicities because its wave vector is nearly perpendicular to the spacecraft trajectory. The radial wave model generated strong Doppler effects of an upshifted and a downshifted signal (a dual period) on either side of the true period, because the wave vector is either parallel or antiparallel to the spacecraft trajectory. Being intermediate to the searchlight and radial waves, the spiral wave produced Doppler effects but only for low wave speeds (<10 RS/h). For higher wave speeds the Doppler effects were not as clear. The Doppler effects can be mitigated by employing only observations beyond ~15 RS where the spacecraft speed is low compared to the wave speed. The observed periodicities over the same 200 day interval do not show evidence of Doppler effects but generally display a single feature at the expected ~10.7 h period.

  12. Formatting Design Dialogues

    DEFF Research Database (Denmark)

    Brandt, Eva; Binder, Thomas; Messeter, Jörn

    2008-01-01

    This article discusses design games as a particular genre for formatting design dialogues. In the first part of the article we review the participatory design literature for game-oriented framings of co-design. We look at what constitutes game and play, we discuss other authors’ use of games...... characteristics in being both ‘as-if’ worlds to explore and shared representations of what the players accomplish. In the last section of the article we discuss how new games may be designed and played and what makes a good design game....

  13. Endocytosis and Enamel Formation

    Directory of Open Access Journals (Sweden)

    Cong-Dat Pham

    2017-07-01

    Full Text Available Enamel formation requires consecutive stages of development to achieve its characteristic extreme mineral hardness. Mineralization depends on the initial presence then removal of degraded enamel proteins from the matrix via endocytosis. The ameloblast membrane resides at the interface between matrix and cell. Enamel formation is controlled by ameloblasts that produce enamel in stages to build the enamel layer (secretory stage and to reach final mineralization (maturation stage. Each stage has specific functional requirements for the ameloblasts. Ameloblasts adopt different cell morphologies during each stage. Protein trafficking including the secretion and endocytosis of enamel proteins is a fundamental task in ameloblasts. The sites of internalization of enamel proteins on the ameloblast membrane are specific for every stage. In this review, an overview of endocytosis and trafficking of vesicles in ameloblasts is presented. The pathways for internalization and routing of vesicles are described. Endocytosis is proposed as a mechanism to remove debris of degraded enamel protein and to obtain feedback from the matrix on the status of the maturing enamel.

  14. Endocytosis and Enamel Formation

    Science.gov (United States)

    Pham, Cong-Dat; Smith, Charles E.; Hu, Yuanyuan; Hu, Jan C-C.; Simmer, James P.; Chun, Yong-Hee P.

    2017-01-01

    Enamel formation requires consecutive stages of development to achieve its characteristic extreme mineral hardness. Mineralization depends on the initial presence then removal of degraded enamel proteins from the matrix via endocytosis. The ameloblast membrane resides at the interface between matrix and cell. Enamel formation is controlled by ameloblasts that produce enamel in stages to build the enamel layer (secretory stage) and to reach final mineralization (maturation stage). Each stage has specific functional requirements for the ameloblasts. Ameloblasts adopt different cell morphologies during each stage. Protein trafficking including the secretion and endocytosis of enamel proteins is a fundamental task in ameloblasts. The sites of internalization of enamel proteins on the ameloblast membrane are specific for every stage. In this review, an overview of endocytosis and trafficking of vesicles in ameloblasts is presented. The pathways for internalization and routing of vesicles are described. Endocytosis is proposed as a mechanism to remove debris of degraded enamel protein and to obtain feedback from the matrix on the status of the maturing enamel. PMID:28824442

  15. The Planet Formation Imager

    Science.gov (United States)

    Kraus, S.; Buscher, D. F.; Monnier, J. D.; PFI Science, the; Technical Working Group

    2014-04-01

    Among the most fascinating and hotly-debated areas in contemporary astrophysics are the means by which planetary systems are assembled from the large rotating disks of gas and dust which attend a stellar birth. Although important work is being done both in theory and observation, a full understanding of the physics of planet formation can only be achieved by opening observational windows able to directly witness the process in action. The key requirement is then to probe planet-forming systems at the natural spatial scales over which material is being assembled. By definition, this is the so-called Hill Sphere which delineates the region of influence of a gravitating body within its surrounding environment. The Planet Formation Imager project has crystallized around this challenging goal: to deliver resolved images of Hill-Sphere-sized structures within candidate planet-hosting disks in the nearest star-forming regions. In this contribution we outline the primary science case of PFI and discuss how PFI could significantly advance our understanding of the architecture and potential habitability of planetary systems. We present radiation-hydrodynamics simulations from which we derive preliminary specifications that guide the design of the facility. Finally, we give an overview about the interferometric and non-interferometric technologies that we are investigating in order to meet the specifications.

  16. Laparoscopic Stoma Formation

    Science.gov (United States)

    Tejirian, Talar

    2008-01-01

    Background: Laparoscopic stoma formation has gained wide acceptance as an alternative to open abdominal surgery. Although laparoscopic stoma formation has a low morbidity, complications have been reported. Contributing factors to these complications are twisting of the bowel, maturing the wrong limb, or both of these. In this report, we describe a simple technique that can reduce these complications. Methods: The bowel segment to be exteriorized is grasped with a locking nontraumatic, nonrotating grasper. After the orientation of the bowel is verified, the surgeon ties the handle of the instrument to the trocar by using a cotton umbilical tape. The trocar and the instrument become one working unit, and if the umbilical tape is wrapped around the shaft of the instrument, then the bowel is twisted. It is easy to untwist it by aligning the umbilical tape with the shaft of the instrument. To mature the stoma, the umbilical tape is removed and the grasper is unlocked. Conclusion: Laparoscopic stoma is an effective treatment for several benign and malignant disorders, and in general has a low morbidity. Our report describes a simple technique that can reduce the rare but significant postoperative stoma or small bowel obstruction. PMID:18435889

  17. FRS Geospatial Return File Format

    Science.gov (United States)

    The Geospatial Return File Format describes format that needs to be used to submit latitude and longitude coordinates for use in Envirofacts mapping applications. These coordinates are stored in the Geospatail Reference Tables.

  18. The formation of citizens: the pediatrician's role.

    Science.gov (United States)

    Campos Júnior, Dioclécio

    2016-01-01

    This review article aims to define the fundamental role of the pediatrician in the formation of citizens in the 21st century. Significant bibliographical contributions produced by neuroscience, ecology, and epigenetics in the early childhood scenario. Many diseases that impair the lives of adults result from severe and often uncontrollable disorders that occur in early childhood, an irreplaceable period for the safe construction of the human brain, personality, and intelligence. There is noteworthy scientific evidence that has become unquestionable, according to which abuse and neglect and other forms of violence to which children are exposed during the course of their lives, are the genesis of many physical ailments and other mental diseases, including depressive morbidity and schizophrenia. Conversely, it is also emphasized that healthy practices such as reading and listening to/playing music are able to intensively contribute to the exercise of cognitive capacity inherent to this period of life, as a prerequisite for the acquisition of learning indispensable to the high educational performance during the schooling period. In the light of the disclosed scientific evidence, the pediatrician emerges as the most differentiated professional to provide preventive and curative care indispensable to the skilled formation of a healthy citizen. Copyright © 2016 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda. All rights reserved.

  19. The formation of citizens: the pediatrician's role

    Directory of Open Access Journals (Sweden)

    Dioclécio Campos Júnior

    2016-06-01

    Full Text Available ABSTRACT Objective: This review article aims to define the fundamental role of the pediatrician in the formation of citizens in the 21st century. Source of data: Significant bibliographical contributions produced by neuroscience, ecology, and epigenetics in the early childhood scenario. Synthesis of data: Many diseases that impair the lives of adults result from severe and often uncontrollable disorders that occur in early childhood, an irreplaceable period for the safe construction of the human brain, personality, and intelligence. There is noteworthy scientific evidence that has become unquestionable, according to which abuse and neglect and other forms of violence to which children are exposed during the the course of their lives, are the genesis of many physical ailments and other mental diseases, including depressive morbidity and schizophrenia. Conversely, it is also emphasized that healthy practices such as reading and listening to/playing music are able to intensively contribute to the exercise of cognitive capacity inherent to this period of life, as a prerequisite for the acquisition of learning indispensable to the high educational performance during the schooling period. Conclusion: In the light of the disclosed scientific evidence, the pediatrician emerges as the most differentiated professional to provide preventive and curative care indispensable to the skilled formation of a healthy citizen.

  20. Mud Volcanoes Formation And Occurrence

    Science.gov (United States)

    Guliyev, I. S.

    2007-12-01

    Mud volcanoes are natural phenomena, which occur throughout the globe. They are found at a greater or lesser scale in Azerbaijan, Turkmenistan, Georgia, on the Kerch and Taman peninsulas, on Sakhalin Island, in West Kuban, Italy, Romania, Iran, Pakistan, India, Burma, China, Japan, Indonesia, Malaysia, New Zealand, Mexico, Colombia, Trinidad and Tobago, Venezuela and Ecuador. Mud volcanoes are most well-developed in Eastern Azerbaijan, where more than 30% of all the volcanoes in the world are concentrated. More than 300 mud volcanoes have already been recognized here onshore or offshore, 220 of which lie within an area of 16,000 km2. Many of these mud volcanoes are particularly large (up to 400 m high). The volcanoes of the South Caspian form permanent or temporary islands, and numerous submarine banks. Many hypotheses have been developed regarding the origin of mud volcanoes. Some of those hypotheses will be examined in the present paper. Model of spontaneous excitation-decompaction (proposed by Ivanov and Guliev, 1988, 2002). It is supposed that one of major factors of the movement of sedimentary masses and formation of hydrocarbon deposits are phase transitions in sedimentary basin. At phase transitions there are abnormal changes of physical and chemical parameters of rocks. Abnormal (high and negative) pressure takes place. This process is called as excitation of the underground environment with periodicity from several tens to several hundreds, or thousand years. The relationship between mud volcanism and the generation of hydrocarbons, particularly methane, is considered to be a critical factor in mud volcano formation. At high flow rates the gas and sediment develops into a pseudo-liquid state and as flow increases the mass reaches the "so-called hover velocity" where mass transport begins. The mass of fluid moves as a quasi-uniform viscous mass through the sediment pile in a piston like manner until expelled from the surface as a "catastrophic eruption

  1. Antarctic Megadunes: Characteristics and Formation

    Science.gov (United States)

    Scambos, T.; Fahnestock, M.; Shuman, C.; Bauer, R.

    2004-12-01

    indicate an ice flow of 4 m/yr at bearing 130, almost perpendicular to the mean wind direction of 226. Dune winds are dominated by flow in this direction (+/- 15 degrees) at 8 - 12 m/s for 10 months of the year. Several possible models for dune formation are considered. Katabatic wind flow of a near-surface air layer clearly controls snow redistriburtion. Previous studies have shown that dunes form in a narrow range of regional surface slope (0.0010 - 0.0015), implying that a specific range of winds speeds may determine formation. One possibility is that wave-like boundary layer effects in the katabatic flow create the dunes. Compaction effects due to the long period of low accumulation in the glaze regions may amplify dune topography. An 'anti-dune' (a term from fluvial geomorphology) model of dune formation is forwarded.

  2. Cooperative Hydrogen Bonding in Amyloid Formation.

    Energy Technology Data Exchange (ETDEWEB)

    Tsemekhman, Kiril L.; Goldschmidt, Lukasz; Eisenberg, Dvaid; Baker, David

    2007-04-01

    The research described in this product was performed in part in the Environmental Molecular Sciences Laboratory, a national scientific user facility sponsored by the Department of Energy's Office of Biological and Environmental Research and located at Pacific Northwest National Laboratory. Amyloid diseases, including Alzheimer's and prion diseases, are each associated with unbranched protein fibrils. Each fibril is made of a particular protein, yet they share common properties. One such property is nucleation-dependent fibril growth. Monomers of amyloid-forming proteins can remain in dissolved form for long periods, before rapidly assembly into fibrils. The lag before growth has been attributed to slow kinetics of formation of a nucleus, on which other molecules can deposit to form the fibril. We have explored the energetics of fibril formation, based on the known molecular structure of a fibril-forming peptide from the yeast prion, Sup35, using both classical and quantum (density functional theory) methods. We find that the energetics of fibril formation for the first three layers are cooperative using both methods. This cooperativity is consistent with the observation that formation of amyloid fibrils involves slow nucleation and faster growth.

  3. School Superintendents' Choices of Professional Periodicals.

    Science.gov (United States)

    Mayo, C. Russell; Zirkel, Perry A.

    2002-01-01

    Reports results of national survey of superintendents' top reading choices from a list of 34 periodicals in educational leadership. Superintendents' top-ranked periodicals are "Educational Leadership,""Phi Delta Kappan,""School Administrator," and "American School Board Journal." (Contains 24 references.) (PKP)

  4. 7 CFR 958.112 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Fiscal period. 958.112 Section 958.112 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... COUNTIES IN IDAHO, AND MALHEUR COUNTY, OREGON Rules and Regulations § 958.112 Fiscal period. The fiscal...

  5. Radial periodic perturbations of the Kepler problem

    Science.gov (United States)

    Fonda, Alessandro; Gallo, Anna Chiara

    2017-11-01

    We consider radial periodic perturbations of a central force field and prove the existence of rotating periodic solutions, whose orbits are nearly circular. The proof is mainly based on the Implicit Function Theorem, and it permits to handle some small perturbations involving the velocity, as well. Our results apply, in particular, to the classical Kepler problem.

  6. Numerical bifurcation of Hamiltonian relative periodic orbits

    DEFF Research Database (Denmark)

    Wulff, Claudia; Schilder, Frank

    2009-01-01

    Relative periodic orbits (RPOs) are ubiquitous in symmetric Hamiltonian systems and occur, for example, in celestial mechanics, molecular dynamics, and the motion of rigid bodies. RPOs are solutions which are periodic orbits of the symmetry-reduced system. In this paper we analyze certain symmetry...

  7. David's Understanding of Functions and Periodicity

    Science.gov (United States)

    Gerson, Hope

    2008-01-01

    This is a study of David, a senior enrolled in a high school precalculus course. David's understandings of functions and periodicity was explored, through clinical interviews and contextualized through classroom observations. Although David's precalculus class was traditional his understanding of periodic functions was unconventional David engaged…

  8. 28 CFR 524.75 - Periodic review.

    Science.gov (United States)

    2010-07-01

    ... 28 Judicial Administration 2 2010-07-01 2010-07-01 false Periodic review. 524.75 Section 524.75... TRANSFER CLASSIFICATION OF INMATES Central Inmate Monitoring (CIM) System § 524.75 Periodic review. The Warden shall ensure that the status of an inmate's CIM assignment is considered at each program review...

  9. Asymptotically periodic solutions of Volterra integral equations

    Directory of Open Access Journals (Sweden)

    Muhammad N. Islam

    2016-03-01

    Full Text Available We study the existence of asymptotically periodic solutions of a nonlinear Volterra integral equation. In the process, we obtain the existence of periodic solutions of an associated nonlinear integral equation with infinite delay. Schauder's fixed point theorem is used in the analysis.

  10. Discontinuous Spirals of Stable Periodic Oscillations

    DEFF Research Database (Denmark)

    Sack, Achim; Freire, Joana G.; Lindberg, Erik

    2013-01-01

    We report the experimental discovery of a remarkable organization of the set of self-generated periodic oscillations in the parameter space of a nonlinear electronic circuit. When control parameters are suitably tuned, the wave pattern complexity of the periodic oscillations is found to increase...

  11. Online Periodic Table: A Cautionary Note

    Science.gov (United States)

    Izci, Kemal; Barrow, Lloyd H.; Thornhill, Erica

    2013-01-01

    The purpose of this study was (a) to evaluate ten online periodic table sources for their accuracy and (b) to compare the types of information and links provided to users. Limited studies have been reported on online periodic table (Diener and Moore 2011; Slocum and Moore in "J Chem Educ" 86(10):1167, 2009). Chemistry students'…

  12. 46 CFR 107.270 - Periodic inspection.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Periodic inspection. 107.270 Section 107.270 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS INSPECTION AND... approves. No written application is required. (c) The scope of the periodic inspection is the same as that...

  13. Periodic Orbits and Deformed Shell Structure

    OpenAIRE

    Arita, K.; Magner, A. G.; Matsuyanagi, K.

    2002-01-01

    Relationship between quantum shell structure and classical periodic orbits is briefly reviewed on the basis of semi-classical trace formula. Using the spheroidal cavity model, it is shown that three-dimensional periodic orbits, which are born out of bifurcation of planar orbits at large prolate deformations, generate the superdeformed shell structure.

  14. 24 CFR 886.332 - Rehabilitation period.

    Science.gov (United States)

    2010-04-01

    ... 24 Housing and Urban Development 4 2010-04-01 2010-04-01 false Rehabilitation period. 886.332... Assistance Program for the Disposition of HUD-Owned Projects § 886.332 Rehabilitation period. (a) Immediate start of rehabilitation after sales closing. After the execution of the Agreement and the sales closing...

  15. 9 CFR 2.101 - Holding period.

    Science.gov (United States)

    2010-01-01

    ... WELFARE REGULATIONS Compliance With Standards and Holding Period § 2.101 Holding period. (a) Any live dog... considered to have acquired a dog or cat which is sold through the auction sale. (1) That any live dog or cat acquired by a dealer or exhibitor from any private or contract animal pound or shelter shall be held by...

  16. Undulating periodization models for strength training & conditioning

    Directory of Open Access Journals (Sweden)

    A. Jiménez

    2009-01-01

    Full Text Available Periodized strength training refers to varying the training program at regular time intervals in an attempt to bring about optimal resistance gains. The main aim of this paper was to present a short review of the diferent aspects of training periodization and its effects with performance. as well as the differential effect of alternate periodization models on other populations, and specially the need for further research regarding the effectiveness of the undulating model as compared with the linear model. A focussed literature review reveals that most studies that examined strength training periodization utilized young males as their subject population, and the research has mainly focused on differences between periodized and non-periodized programs. Furthermore, the periodization training programs are designed and developed according to two different models: the linear model and the non-linear model. The Linear Model is characterized by high initial training volume and low and intensity. The Non-Linear Model enables variation in intensity and volume within each 7-10 day cycle by rotating different protocols to train various components of the neuromuscular system. The results showed at the scientific literature encourage researchers and exercise professionals to include non-linear (undulating periodization models during resistance training.

  17. Undulating periodization models for strength training & conditioning

    Directory of Open Access Journals (Sweden)

    A. Jiménez

    2009-09-01

    Full Text Available Periodized strength training refers to varying the training program at regular time intervals in an attempt to bring about optimal resistance gains. The main aim of this paper was to present a short review of the diferent aspects of training periodization and its effects with performance. as well as the differential effect of alternate periodization models on other populations, and specially the need for further research regarding the effectiveness of the undulating model as compared with the linear model. A focussed literature review reveals that most studies that examined strength training periodization utilized young males as their subject population, and the research has mainly focused on differences between periodized and non-periodized programs. Furthermore, the periodization training programs are designed and developed according to two different models: the linear model and the non-linear model. The Linear Model is characterized by high initial training volume and low and intensity. The Non-Linear Model enables variation in intensity and volume within each 7-10 day cycle by rotating different protocols to train various components of the neuromuscular system. The results showed at the scientific literature encourage researchers and exercise professionals to include non-linear (undulating periodization models during resistance training.

  18. Multi-periodic nanostructures for photon control

    DEFF Research Database (Denmark)

    Kluge, Christian; Adam, Jost; Barié, Nicole

    2014-01-01

    We propose multi-periodic nanostructures yielded by superposition of multiple binary gratings for wide control over photon emission in thin-film devices. We present wavelength- and angle-resolved photoluminescence measurements of multi-periodically nanostructured organic light-emitting layers...

  19. For the period ending 30 September 2017

    International Development Research Centre (IDRC) Digital Library (Canada)

    Office 2004 Test Drive User

    2017-09-30

    Sep 30, 2017 ... same reasons described in the donor contribution revenues paragraph (see page 8). The year-over- year increase for the six months ended 30 September was anticipated and is reflected in this year's budget, which is higher than the 2016-2017 actuals for the same period. Compared to the same period ...

  20. 46 CFR 403.115 - Accounting period.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 8 2010-10-01 2010-10-01 false Accounting period. 403.115 Section 403.115 Shipping COAST GUARD (GREAT LAKES PILOTAGE), DEPARTMENT OF HOMELAND SECURITY GREAT LAKES PILOTAGE UNIFORM ACCOUNTING SYSTEM General § 403.115 Accounting period. Each Association subject to this part shall maintain...

  1. 18 CFR 367.5 - Accounting period.

    Science.gov (United States)

    2010-04-01

    ... 18 Conservation of Power and Water Resources 1 2010-04-01 2010-04-01 false Accounting period. 367.5 Section 367.5 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION... Instructions § 367.5 Accounting period. Each service company must keep its books on a monthly basis so that for...

  2. 20 CFR 655.205 - Recruitment period.

    Science.gov (United States)

    2010-04-01

    ... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false Recruitment period. 655.205 Section 655.205... Agricultural Employment § 655.205 Recruitment period. (a) If the OFLC Administrator determines that the... carry out the assurances contained in § 655.203 with respect to the recruitment of U.S. workers. The...

  3. Studying the Nazi Period: Some Considerations.

    Science.gov (United States)

    Molnar, Alex; And Others

    1984-01-01

    Students should be taught how to make well-reasoned and analytic judgments about the Nazis. The process of arriving at judgments about the Nazi period should be characterized by a factual knowledge of the Nazi era within a general historical knowledge of the period, sympathy, and an open mind. (RM)

  4. Project 2nd Periodic Report - Section 2

    DEFF Research Database (Denmark)

    Healy, Mark; Knowles, Emma; Johnstone, Cameron

    The work described in this publication has received support from the European Community - Research Infrastructure Action under the FP7 “Capacities” Specific Programme through grant agreement number 262552, MaRINET. Project Periodic Report. 2nd Period: October 2012 – March 2014 inclusive....

  5. Period Variations for the Cepheid VZ Cyg

    Science.gov (United States)

    Sirorattanakul, Krittanon; Engle, Scott; Pepper, Joshua; Wells, Mark; Laney, Clifton D.; Rodriguez, Joseph E.; Stassun, Keivan G.

    2017-12-01

    The Cepheid Period-Luminosity law is a key rung on the extragalactic distance ladder. However, numerous Cepheids are known to undergo period variations. Monitoring, refining, and understanding these period variations allows us to better determine the parameters of the Cepheids themselves and of the instability strip in which they reside, and to test models of stellar evolution. VZ Cyg, a classical Cepheid pulsating at ˜4.864 days, has been observed for over 100 years. Combining data from literature observations, the Kilodegree Extremely Little Telescope (KELT) transit survey, and new targeted observations with the Robotically Controlled Telescope (RCT) at Kitt Peak, we find a period change rate of dP/dt = -0.0642 ± 0.0018 s yr-1. However, when only the recent observations are examined, we find a much higher period change rate of dP/dt = -0.0923 ± 0.0110 s yr-1. This higher rate could be due to an apparent long-term (P ≈ 26.5 years) cyclic period variation. The possible interpretations of this single Cepheid’s complex period variations underscore both the need to regularly monitor pulsating variables and the important benefits that photometric surveys such as KELT can have on the field. Further monitoring of this interesting example of Cepheid variability is recommended to confirm and better understand the possible cyclic period variations. Further, Cepheid timing analyses are necessary to fully understand their current behaviors and parameters, as well as their evolutionary histories.

  6. Periodization Theory: Confronting an Inconvenient Truth.

    Science.gov (United States)

    Kiely, John

    2017-11-30

    Periodization theory has, over the past seven decades, emerged as the preeminent training planning paradigm. The philosophical underpinnings of periodization theory can be traced back to the integration of diverse shaping influences, whereby coaching beliefs and traditions were blended with historically available scientific insights and contextualized against pervading social planning models. Since then, many dimensions of elite preparation have evolved significantly, as driven by a combination of coaching innovations and science-led advances in training theory, techniques, and technologies. These advances have been incorporated into the fabric of the pre-existing periodization planning framework, yet the philosophical assumptions underpinning periodization remain largely unchallenged and unchanged. One particularly influential academic sphere of study, the science of stress, particularly the work of Hans Selye, is repeatedly cited by theorists as a central pillar upon which periodization theory is founded. A fundamental assumption emanating from the early stress research is that physical stress is primarily a biologically mediated phenomenon: a presumption translated to athletic performance contexts as evidence that mechanical training stress directly regulates the magnitude of subsequent 'fitness' adaptations. Interestingly, however, since periodization theory first emerged, the science of stress has evolved extensively from its historical roots. This raises a fundamental question: if the original scientific platform upon which periodization theory was founded has disintegrated, should we critically re-evaluate conventional perspectives through an updated conceptual lens? Realigning periodization philosophy with contemporary stress theory thus presents us with an opportunity to recalibrate training planning models with both contemporary scientific insight and progressive coaching practice.

  7. Designing for informed group formation

    DEFF Research Database (Denmark)

    Nicolajsen, Hanne Westh; Juel Jacobsen, Alice; Riis, Marianne

    2012-01-01

    A new design ―project preparation‖ preparing for the group formation in problem based project work is proposed and investigated. The main problem is to overcome group formation based on existing relations. The hypothesis is that theme development and group formation are somewhat counterproductive...

  8. New Realization of Periodic Cycled Separation

    DEFF Research Database (Denmark)

    Toftegard, Bjarne; Clausen, Charlotte H.; Jørgensen, Sten B.

    2016-01-01

    A new realization of periodic cycled gas/liquid separation is presented. Separation factors and column efficiencies are compared for a column stripping ammonia from water with air, using three different sets of internals: conventional sieve trays, Sulzer BX gauze packings, and periodically cycled...... trays. The proposed new periodic trays are shown to be advantageous compared to their continuous alternatives. It is demonstrated experimentally that periodic tray efficiencies of up to 300% are achievable. With the proposed new tray design, a new operation form is also introduced in which the trays...... are drained sequentially rather than simultaneously, such that the vapor flow is not interrupted during the liquid drainage. For different ratios of counter-current vapor/liquid flow rates, column efficiencies for periodically cycled columns are shown experimentally to be two times greater than those...

  9. Hypokalemic periodic paralysis: Three rare secondary causes

    Directory of Open Access Journals (Sweden)

    Prasanna Eswaradass Venkatesan

    2015-01-01

    Full Text Available Periodic paralysis is a rare neuromuscular disorder, related to a defect in muscle ion channels, characterized by episodes of painless muscle weakness, which may be precipitated by heavy exercise, fasting, or high-carbohydrate meals. Hypokalemic periodic paralysis may be familial (primary or secondary. Here, we report three cases of secondary causes of hypokalemic periodic paralysis. On evaluation, case 1 had distal renal tubular acidosis (RTA due to Sjogren′s syndrome, case 2 had drug induced proximal RTA (Fanconi′s syndrome and case 3 had thyrotoxicosis. Clinician must be aware of causes of secondary PP as recognition and diagnosis can completely prevent further attacks of periodic paralysis. Each of the above case is rare, but completely treatable if diagnosed. Low dose steroids with bicarbonate replacement in case 1, stopping tenofovir in case 2 and carbimazole therapy in case 3 prevented further attacks of periodic paralysis and cardiopulmonary complications.

  10. The formation mechanism of chiral carbon nanotubes

    Science.gov (United States)

    Liu, Jing; Liu, Liren; Lu, Junzhe; Zhu, Hengjiang

    2018-02-01

    The nuclei and the formation mechanism of chiral carbon nanotubes, namely, single-, double-, and triple-walled carbon nanotubes are simulated by the first principle density functional theory. The formation mechanism from nuclei to corresponding infinitely long carbon nanotubes occurs spirally and via absorbing carbon atoms layer by layer. Carbon atoms at the open end are metastable state compared with ones in the tube wall or the closed end, which indicate the growth point of chiral carbon nanotubes is located at the open end. Growth of outer layer tubular clusters takes precedence over the inner layer in the process of forming multi-walled nuclear structures. Because of the ratio of carbon atoms at the open end to all carbon atoms decreases, the stability of the tubular clusters increases with their length. The infinitely long carbon nanotubes are obtained by executing periodic boundary conditions depend on corresponding nuclear structures.

  11. The period function of reversible quadratic centers

    Science.gov (United States)

    Mardešić, P.; Marín, D.; Villadelprat, J.

    In this paper we investigate the bifurcation diagram of the period function associated to a family of reversible quadratic centers, namely the dehomogenized Loud's systems. The local bifurcation diagram of the period function at the center is fully understood using the results of Chicone and Jacobs [C. Chicone, M. Jacobs, Bifurcation of critical periods for plane vector fields, Trans. Amer. Math. Soc. 312 (1989) 433-486]. Most of the present paper deals with the local bifurcation diagram at the polycycle that bounds the period annulus of the center. The techniques that we use here are different from the ones in [C. Chicone, M. Jacobs, Bifurcation of critical periods for plane vector fields, Trans. Amer. Math. Soc. 312 (1989) 433-486] because, while the period function extends analytically at the center, it has no smooth extension to the polycycle. At best one can hope that it has some asymptotic expansion. Another major difficulty is that the asymptotic development has to be uniform with respect to the parameters, in order to prove that a parameter is not a bifurcation value. We study also the bifurcations in the interior of the period annulus and we show that there exist three germs of curves in the parameter space that correspond to this type of bifurcation. Moreover we determine some regions in the parameter space for which the corresponding period function has at least one or two critical periods. Finally we propose a complete conjectural bifurcation diagram of the period function of the dehomogenized Loud's systems. Our results can also be viewed as a contribution to the proof of Chicone's conjecture [C. Chicone, review in MathSciNet, ref. 94h:58072].

  12. Determination of Initial Conditions for Tetrahedral Satellite Formation

    Directory of Open Access Journals (Sweden)

    Sung-Moon Yoo

    2011-12-01

    Full Text Available This paper presents an algorithm that can provide initial conditions for formation flying at the beginning of a region of interest to maximize scientific mission goals in the case of a tetrahedral satellite formation. The performance measure is to maximize the quality factor that affects scientific measurement performance. Several path constraints and periodicity conditions at the beginning of the region of interest are identified. The optimization problem is solved numerically using a direct transcription method. Our numerical results indicate that there exist an optimal configuration and states of a tetrahedral satellite formation. Furthermore, the initial states and algorithm presented here may be used for reconfiguration maneuvers and fuel balancing problems.

  13. The Use of Format Adaptation in Danish Public Service Programming

    DEFF Research Database (Denmark)

    Jensen, Pia Majbritt

    2013-01-01

    The article investigates Danish public service broadcasters’ use of format adaptations over a 12-year period in order to examine claims that formats constitute a potential threat to public service broadcasting and the national Danish television industry and culture. The article’s findings, however......, bear little evidence to support these claims. The practice of format adaptation constitutes a comparatively small proportion of the overall production of Danish public service content, and, more importantly, most of the formats adapted by the public broadcasters have a comparatively solid public...... service orientation. Instead the article argues, following German sociologist Ulrich Beck, that format adaptation can represent a form of ‘banal transnationalism’, pointing to the fact that the world is no longer exclusively defined by national boundaries....

  14. Group Formation in Economics

    Science.gov (United States)

    Demange, Gabrielle; Wooders, Myrna

    2005-01-01

    Broad and diverse ranges of activities are conducted within and by organized groups of individuals, including political, economic and social activities. These activities have recently become a subject of intense interest in economics and game theory. Some of the topics investigated in this collection are models of networks of power and privilege, trade networks, co-authorship networks, buyer-seller networks with differentiated products, and networks of medical innovation and the adaptation of new information. Other topics are social norms on punctuality, clubs and the provision of club goods and public goods, research and development and collusive alliances among corporations, and international alliances and trading agreements. While relatively recent, the literature on game theoretic studies of group formation in economics is already vast. This volume provides an introduction to this important literature on game-theoretic treatments of situations with networks, clubs, and coalitions, including some applications.

  15. Myxobacteria Fruiting Body Formation

    Science.gov (United States)

    Jiang, Yi

    2006-03-01

    Myxobacteria are social bacteria that swarm and glide on surfaces, and feed cooperatively. When starved, tens of thousands of cells change their movement pattern from outward spreading to inward concentration; they form aggregates that become fruiting bodies, inside which cells differentiate into nonmotile, environmentally resistant spores. Traditionally, cell aggregation has been considered to imply chemotaxis, a long-range cell interaction mediated by diffusing chemicals. However, myxobacteria aggregation is the consequence of direct cell-contact interactions. I will review our recent efforts in modeling the fruiting body formation of Myxobacteria, using lattice gas cellular automata models that are based on local cell-cell contact signaling. These models have reproduced the individual phases in Myxobacteria development such as the rippling, streaming, early aggregation and the final sporulation; the models can be unified to simulate the whole developmental process of Myxobacteria.

  16. Pattern Formation in Materials

    Science.gov (United States)

    Karma, Alain

    2011-04-01

    Pattern formation is ubiquitous in nature, from sand ripples formed by wind to the development of a complex biological organism with different organs and a central nervous system. In the realm of materials, patterns are formed invariably when matter is transformed between different solid, liquid or gaseous states far from thermodynamic equilibrium. Material failure is itself mediated by the propagation of cracks that form intricate patterns. Understanding how patterns form and evolve is key to design materials with desired properties and to optimize their performance and safety. This talk will discuss recent progress made to understand three distinct class of patterns including the highly branched snow-flake-like dendritic patterns formed during the solidification process, polycrystalline patterns shaped by grain boundaries, and crack patterns.

  17. Recipes for planet formation

    Science.gov (United States)

    Meyer, Michael R.

    2009-11-01

    Anyone who has ever used baking soda instead of baking powder when trying to make a cake knows a simple truth: ingredients matter. The same is true for planet formation. Planets are made from the materials that coalesce in a rotating disk around young stars - essentially the "leftovers" from when the stars themselves formed through the gravitational collapse of rotating clouds of gas and dust. The planet-making disk should therefore initially have the same gas-to-dust ratio as the interstellar medium: about 100 to 1, by mass. Similarly, it seems logical that the elemental composition of the disk should match that of the star, reflecting the initial conditions at that particular spot in the galaxy.

  18. Periodic precipitation a microcomputer analysis of transport and reaction processes in diffusion media, with software development

    CERN Document Server

    Henisch, H K

    1991-01-01

    Containing illustrations, worked examples, graphs and tables, this book deals with periodic precipitation (also known as Liesegang Ring formation) in terms of mathematical models and their logical consequences, and is entirely concerned with microcomputer analysis and software development. Three distinctive periodic precipitation mechanisms are included: binary diffusion-reaction; solubility modulation, and competitive particle growth. The book provides didactic illustrations of a valuable investigational procedure, in the form of hypothetical experimentation by microcomputer. The development

  19. Superluminal periodic orbits in the Lorenz system

    Science.gov (United States)

    Algaba, A.; Merino, M.; Rodríguez-Luis, A. J.

    2016-10-01

    In this work we present, for the Lorenz system, analytical and numerical results on the existence of periodic orbits with unbounded amplitude and whose period tends to zero. Since a particle moving on these periodic orbits would be faster-than-light, we call them superluminal periodic orbits. To achieve this goal, we first find analytical expressions for the period in three different situations, where Hopf and Takens-Bogdanov bifurcations of infinite codimension occur. Thus, taking limit in the corresponding expressions allows to demonstrate the existence of superluminal periodic orbits for finite values of the parameter ρ (in a region where the other two parameters σ and b are negative). Moreover, we numerically show, in other two different cases of physical interest, that these orbits also exist when the parameter ρ tends to infinity. Finally, the presence of superluminal periodic orbits in the widely studied Chen and Lü systems follows directly from our results, taking into account that they are, generically, particular cases of the Lorenz system, as can be proved with a linear scaling in time and state variables.

  20. Torpedo: topic periodicity discovery from text data

    Science.gov (United States)

    Wang, Jingjing; Deng, Hongbo; Han, Jiawei

    2015-05-01

    Although history may not repeat itself, many human activities are inherently periodic, recurring daily, weekly, monthly, yearly or following some other periods. Such recurring activities may not repeat the same set of keywords, but they do share similar topics. Thus it is interesting to mine topic periodicity from text data instead of just looking at the temporal behavior of a single keyword/phrase. Some previous preliminary studies in this direction prespecify a periodic temporal template for each topic. In this paper, we remove this restriction and propose a simple yet effective framework Torpedo to mine periodic/recurrent patterns from text, such as news articles, search query logs, research papers, and web blogs. We first transform text data into topic-specific time series by a time dependent topic modeling module, where each of the time series characterizes the temporal behavior of a topic. Then we use time series techniques to detect periodicity. Hence we both obtain a clear view of how topics distribute over time and enable the automatic discovery of periods that are inherent in each topic. Theoretical and experimental analyses demonstrate the advantage of Torpedo over existing work.

  1. Periodicity of extinction: A 1988 update

    Science.gov (United States)

    Sepkowski, J. John, Jr.

    1988-01-01

    The hypothesis that events of mass extinction recur periodically at approximately 26 my intervals is an empirical claim based on analysis of data from the fossil record. The hypothesis has become closely linked with catastrophism because several events in the periodic series are associated with evidence of extraterrestrial impacts, and terrestrial forcing mechanisms with long, periodic recurrences are not easily conceived. Astronomical mechanisms that have been hypothesized include undetected solar companions and solar oscillation about the galactic plane, which induce comet showers and result in impacts on Earth at regular intervals. Because these mechanisms are speculative, they have been the subject of considerable controversy, as has the hypothesis of periodicity of extinction. In response to criticisms and uncertainties, a data base was developed on times of extinction of marine animal genera. A time series is given and analyzed with 49 sample points for the per-genus extinction rate from the Late Permian to the Recent. An unexpected pattern in the data is the uniformity of magnitude of many of the periodic extinction events. Observations suggest that the sequence of extinction events might be the result of two sets of mechanisms: a periodic forcing that normally induces only moderate amounts of extinction, and independent incidents or catastrophes that, when coincident with the periodic forcing, amplify its signal and produce major-mass extinctions.

  2. Periodic solutions of dissipative systems revisited

    Directory of Open Access Journals (Sweden)

    Lech Górniewicz

    2006-05-01

    Full Text Available We reprove in an extremely simple way the classical theorem that time periodic dissipative systems imply the existence of harmonic periodic solutions, in the case of uniqueness. We will also show that, in the lack of uniqueness, the existence of harmonics is implied by uniform dissipativity. The localization of starting points and multiplicity of periodic solutions will be established, under suitable additional assumptions, as well. The arguments are based on the application of various asymptotic fixed point theorems of the Lefschetz and Nielsen type.

  3. Periodic solutions of dissipative systems revisited

    Directory of Open Access Journals (Sweden)

    Górniewicz Lech

    2006-01-01

    Full Text Available We reprove in an extremely simple way the classical theorem that time periodic dissipative systems imply the existence of harmonic periodic solutions, in the case of uniqueness. We will also show that, in the lack of uniqueness, the existence of harmonics is implied by uniform dissipativity. The localization of starting points and multiplicity of periodic solutions will be established, under suitable additional assumptions, as well. The arguments are based on the application of various asymptotic fixed point theorems of the Lefschetz and Nielsen type.

  4. Variable-Period Undulators For Synchrotron Radiation

    Energy Technology Data Exchange (ETDEWEB)

    Shenoy, Gopal (Naperville, IL); Lewellen, John (Plainfield, IL); Shu, Deming (Darien, IL); Vinokurov, Nikolai (Novosibirsk, RU)

    2005-02-22

    A new and improved undulator design is provided that enables a variable period length for the production of synchrotron radiation from both medium-energy and high-energy storage rings. The variable period length is achieved using a staggered array of pole pieces made up of high permeability material, permanent magnet material, or an electromagnetic structure. The pole pieces are separated by a variable width space. The sum of the variable width space and the pole width would therefore define the period of the undulator. Features and advantages of the invention include broad photon energy tunability, constant power operation and constant brilliance operation.

  5. Variable-Period Undulators for Synchrotron Radiation

    Energy Technology Data Exchange (ETDEWEB)

    Shenoy, Gopal; Lewellen, John; Shu, Deming; Vinokurov, Nikolai

    2005-02-22

    A new and improved undulator design is provided that enables a variable period length for the production of synchrotron radiation from both medium-energy and high energy storage rings. The variable period length is achieved using a staggered array of pole pieces made up of high permeability material, permanent magnet material, or an electromagnetic structure. The pole pieces are separated by a variable width space. The sum of the variable width space and the pole width would therefore define the period of the undulator. Features and advantages of the invention include broad photon energy tunability, constant power operation and constant brilliance operation.

  6. A method to extract successive velocity pulses governing structural response from long-period ground motion

    Science.gov (United States)

    Liu, Shuoyu; Li, Yingmin; Wang, Guojue

    2017-11-01

    A series of relatively long-period velocity pulses appearing in the later part of ground motion, which is the characterization of far-source long-period ground motions in basin ("long-period ground motion" for short), is mainly influenced by focal mechanism, basin effect, and dispersion. It was supposed that the successive low-frequency velocity pulses in long-period ground motion caused the resonance of long-period structures in basin, which are of special concern to designers of super high-rise buildings. The authors proposed a wavelet-based successive frequency-dependent pulse extraction (WSFPE) method to identify and extract these pulses with dominant period of interest from long-period ground motions. The pulses extracted by using two frequently used methods (zero-crossing analysis, empirical mode decomposition) were compared to the pulses extracted by using WSFPE. The results demonstrate that the WSFPE provides higher resolution in time-frequency domain than the other two methods do. The velocity pulses extracted by using WSFPE are responsible for the resonance and maximum response of structure subjected to long-period ground motions. WSFPE can be used to make a better understanding of long-period ground motions and to promote the formation of long-period ground motion model which will help the seismic design of long-period structures built in sedimentary basin.

  7. Almost periodic solutions of impulsive differential equations

    CERN Document Server

    Stamov, Gani T

    2012-01-01

    Impulsive differential equations are suitable for the mathematical simulation of evolutionary processes in which the parameters undergo relatively long periods of smooth variation followed by short-term rapid changes (that is, jumps) in their values. Processes of this type are often investigated in various fields of science and technology. The question of the existence and uniqueness of almost periodic solutions of differential equations is an age-old problem of great importance. The qualitative theory of impulsive differential equations is currently undergoing rapid development in relation to the investigation of various processes which are subject to impacts during their evolution, and many findings on the existence and uniqueness of almost periodic solutions of these equations are being made. This book systematically presents findings related to almost periodic solutions of impulsive differential equations and illustrates their potential applications.

  8. Galactic Dark Matter and Terrestrial Periodicities

    National Research Council Canada - National Science Library

    Clube, S

    1998-01-01

    .... The Earth may thus be regarded as a probe of the disc environment; and to account for the periodicity, the Galactic disc is required to have a substantial dark matter component ( approx .15 molar mass/cu pc...

  9. Early and Periodic Screening, Diagnosis and Treatment

    Data.gov (United States)

    U.S. Department of Health & Human Services — The Early and Periodic Screening, Diagnostic and Treatment (EPSDT) benefit provides comprehensive and preventive health care services for children under age 21 who...

  10. Difficulties in enforcing the new probation period

    Directory of Open Access Journals (Sweden)

    Raluca DIMITRIU

    2011-06-01

    Full Text Available During probation period, the employee is in a fragile position: he/she cannot be sure about the continuation of his/her labour relation. Law no 40/2011 modified the Labour Code in the sense of extending the probation periods in the case of contracts with non-fixed term and temporary contracts. Besides, according to the new provision, the period of time during which the employer may hire successively for probation periods several individuals for the same position is 12 months, the most. The paper aims to put into light the way in which the new regulations are to be applied, and several difficulties that this may bring in practice.

  11. Time-Varying Periodicity in Intraday Volatility

    DEFF Research Database (Denmark)

    Andersen, Torben Gustav; Thyrsgaard, Martin; Todorov, Viktor

    with a constant time-of-day periodic component. We first construct time-of-day volatility estimates and studentize the high-frequency returns with these periodic components. If the intraday volatility periodicity is invariant over time, then the distribution of the studentized returns should be identical across......We develop a nonparametric test for deciding whether return volatility exhibits time-varying intraday periodicity using a long time-series of high-frequency data. Our null hypothesis, commonly adopted in work on volatility modeling, is that volatility follows a stationary process combined...... the trading day. Consequently, the test is based on comparing the empirical characteristic function of the studentized returns across the trading day. The limit distribution of the test depends on the error in recovering volatility from discrete return data and the empirical process error associated...

  12. Broiler adaptation to post-hatching period

    Directory of Open Access Journals (Sweden)

    Maiorka Alex

    2006-01-01

    Full Text Available In the latest years more attention has been given to mechanisms for bird adaptation at post-hatching period by management of environmental conditions and formulations of diets offered during this period when digestive, immune, and thermo-regulating systems suffer slight changes. In post-hatching period, digestive system is anatomically complete, but its functionality is still immature in relation to adult birds. The chick immunity depends on maternal antibodies transferred to egg just before laying. In addition, variations within thermal comfort zone might affect initial development of chick. For example, high temperatures may induce hyperthermia with dehydration, while low temperatures may lead to hypothermia responsible by pulmonary hypertension syndrome. In conclusion, productivity might be enhanced when good conditions are offered to chicks during the period from last embryo development to first days after hatching.

  13. Astrobee Periodic Technical Review (PTR) Delta 3

    Science.gov (United States)

    Provencher, Christopher; Smith, Marion F.; Smith, Ernest Everett; Bualat, Maria Gabriele; Barlow, Jonathan Spencer

    2017-01-01

    Astrobee is a free flying robot for the inside of the International Space Station (ISS). The Periodic Technical Review (PTR) delta 3 is the final design review of the system presented to stakeholders.

  14. Periodic words connected with the Fibonacci words

    Directory of Open Access Journals (Sweden)

    G. M. Barabash

    2016-06-01

    Full Text Available In this paper we introduce two families of periodic words (FLP-words of type 1 and FLP-words of type 2 that are connected with the Fibonacci words and investigated their properties.

  15. Concurrent hypokalemic periodic paralysis and bipolar disorder

    Directory of Open Access Journals (Sweden)

    Chia-Lin Lin

    2015-01-01

    Full Text Available Primary periodic paralysis is a rare autosomal dominant disorder of ion-channel dysfunction, manifested by episodic flaccid paresis secondary to abnormal sarcolemma excitability. Membrane destabilization involving Na, K-ATPase has been hypothesized to be a biological etiology of the bipolar disorder (BD and the mechanisms underlying lithium therapy have been linked to it. To date, there has been only one reported case of BD comorbid with periodic paralysis. Herein, we reported another case of concurrent bipolar mania and hypokalemic periodic paralysis (HPP, one special form of periodic paralysis. Consistent with the previous case, our patient responded well to lithium treatment for both bipolar mania and HPP. This might provide some support to the hypothesis that the therapeutic effects of lithium in both BD and HPP could be due to the correction of the underlying common pathophysiology.

  16. Transversally periodic solitary gravity–capillary waves

    Science.gov (United States)

    Milewski, Paul A.; Wang, Zhan

    2014-01-01

    When both gravity and surface tension effects are present, surface solitary water waves are known to exist in both two- and three-dimensional infinitely deep fluids. We describe here solutions bridging these two cases: travelling waves which are localized in the propagation direction and periodic in the transverse direction. These transversally periodic gravity–capillary solitary waves are found to be of either elevation or depression type, tend to plane waves below a critical transverse period and tend to solitary lumps as the transverse period tends to infinity. The waves are found numerically in a Hamiltonian system for water waves simplified by a cubic truncation of the Dirichlet-to-Neumann operator. This approximation has been proved to be very accurate for both two- and three-dimensional computations of fully localized gravity–capillary solitary waves. The stability properties of these waves are then investigated via the time evolution of perturbed wave profiles. PMID:24399922

  17. Stability of Periodic Locomotion in Potential Flow

    CERN Document Server

    Jing, Fangxu

    2013-01-01

    Most aquatic vertebrates swim by lateral flapping of their bodies and caudal fins. While much effort has been devoted to understanding the flapping kinematics and its influence on the swimming efficiency, little is known about the stability (or lack of) of periodic swimming. In this paper, we examine the stability of periodic locomotion due to sideways flapping in unbounded potential flow. It is believed that stability limits maneuverability and body designs/flapping motions that are adapted for stable swimming are not suitable for high maneuverability and vice versa. Here, we consider a simplified model where the swimmer is a planar elliptic body undergoing prescribed periodic heaving and pitching. We show that periodic locomotion can be achieved due to the resulting hydrodynamic forces, and its value depends on several parameters including the aspect ratio of the body, the amplitudes and phases of the prescribed flapping. We obtain closed-form solutions for the locomotion and efficiency for small flapping a...

  18. Ecological periodic tables: In principle and practice

    Science.gov (United States)

    The chemical periodic table, the Linnaean system of classification and the Hertzsprung-Russell diagram are iconic information organizing structure in chemistry, biology and astronomy, respectively, because they are simple, exceptionally useful and they foster the expansion of sci...

  19. Genetics Home Reference: hyperkalemic periodic paralysis

    Science.gov (United States)

    ... cold temperatures, certain medications, and periods without food (fasting). Muscle strength usually returns to normal between attacks, ... from Genetics Home Reference Bulletins November is Lung Cancer Awareness Month Celebrating National Family Health History Day ...

  20. SQL Application for Periodic System of Elements

    Directory of Open Access Journals (Sweden)

    Delia GLIGOR

    2004-02-01

    Full Text Available The paper presents SQL power of periodic system using for didactic aim. The article is based on a PHP application developed to present a periodic system in a form, which can be used for answer at different questions, which can be asked related at the structure of elements. There are presented all queries that are needed to be use for classification of elements after different properties, the database, and user interface design.

  1. Coupled mode theory of periodic waveguides arrays

    DEFF Research Database (Denmark)

    Lavrinenko, Andrei; Chigrin, Dmitry N.

    We apply the scalar coupled mode theory to the case of waveguides array consisting om two periodic waveguides. One of the waveguides is arbitrary shifted along another. A longitudinal shift acts as a parameter in the coupled mode theory. The proposed theory explains peculiarities of modes dispers...... dispersion and transmission in coupled periodic waveguides systems. Analytical results are compared with the numerical ones obtained by the plane wave expansion and FDTD methods....

  2. Wavefunction Intensity Statistics from Unstable Periodic Orbits

    CERN Document Server

    Kaplan, L

    1998-01-01

    We examine the effect of short unstable periodic orbits on wavefunction statistics in a classically chaotic system, and find that the tail of the wavefunction intensity distribution in phase space is dominated by scarring associated with the least unstable periodic orbits. In an ensemble average over systems with classical orbits of different instabilities, a power law tail is found, in sharp contrast to the exponential prediction of random matrix theory. The calculations are compared with numerical data and quantitative agreement is obtained

  3. IUPAC Periodic Table of the Isotopes

    Science.gov (United States)

    Holden, N.E.; Coplen, T.B.; Böhlke, J.K.; Wieser, M.E.; Singleton, G.; Walczyk, T.; Yoneda, S.; Mahaffy, P.G.; Tarbox, L.V.

    2011-01-01

    For almost 150 years, the Periodic Table of the Elements has served as a guide to the world of elements by highlighting similarities and differences in atomic structure and chemical properties. To introduce students, teachers, and society to the existence and importance of isotopes of the chemical elements, an IUPAC Periodic Table of the Isotopes (IPTI) has been prepared and can be found as a supplement to this issue.

  4. Periodization Theory: Confronting an inconvenient truth

    OpenAIRE

    Kiely, John

    2017-01-01

    Periodization theory has, over the past seven decades, emerged as the preeminent training planning paradigm. The philosophical underpinnings of periodization theory can be traced back to the integration of diverse shaping influences, whereby coaching beliefs and traditions were blended with historically available scientific insights and contextualized against pervading social planning models. Since then, many dimensions of elite preparation have evolved significantly, as driven by a combinati...

  5. Faraday rotation effect in periodic graphene structure

    Science.gov (United States)

    Liu, Daqing; Zhang, Shengli; Ma, Ning; Li, Xinghua

    2012-07-01

    We report the magneto-optical (MO) rotation effect in a periodic graphene-sheet structure. Due to the masslessness of carriers in graphene, the magnetic response is very sensitive and the magneto-optical rotation effect is therefore significant. We predict that the Verdet constant of the periodic graphene-sheet structure is roughly 10-100 times that of rare-earth-doped magneto-optical glass in the infrared region.

  6. Faraday rotation effect in periodic graphene structure

    OpenAIRE

    Liu, Daqing; Zhang, Shengli; Ma, Ning; Li, Xinghua

    2012-01-01

    We report the magneto-optical rotation effect in a periodic graphene-sheet structure. Due to the masslessness of carriers in graphene, the magnetic response is very sensitive and the magneto-optical rotation effect is therefore significant. We predict that the Verdet constant of the periodic graphene-sheet structure is roughly 10-100 times that of rare-earth-doped magneto-optical glass in the infrared region.

  7. of the related period. Accordingly, the corresponding

    African Journals Online (AJOL)

    the equation i = 22.04(1.lO. (1) has been established to represent the extreme rainfall intensity-duration function that characterized the given period at this Station. In the equation i denotes the intensity of rain f:all (mm/hr) and t the observed duration of the related ''uniform" period (hr). The author is fully aware of the fact that ...

  8. Short Period Variables in Leo A

    Science.gov (United States)

    Dolphin, A. E.; Saha, A.; Claver, J.; Skillman, E. D.; Cole, A. A.; Gallagher, J. S.; Tolstoy, E.; Dohm-Palmer, R. C.; Mateo, M.

    2001-12-01

    We present the results of a search for short-period variable stars in Leo A. We have found 92 candidate variables: 8 candidate RR Lyrae stars and 84 short-period Cepheids. From the RR Lyraes, we measure a distance modulus of (m-M)0 = 24.51 +/- 0.12, or 0.80 +/- 0.04 Mpc. This discovery of RR Lyraes confirms, for the first time, the presence of an ancient (> ~ 11 Gyr) population in Leo A accounting for at least 0.1% of the galaxy's V luminosity. We have also discovered a halo of old (> ~ 2 Gyr) stars surrounding Leo A, with a scale length roughly 50% larger than that of the dominant young population. The median absolute magnitude of our Cepheid sample is MV = -1.1, fainter than 95.5% of SMC and 98.9% of LMC Cepheids. Their periods are also unusual, with three Cepheids that are deduced to be pulsating in the fundamental mode having periods of under 1 day. Upon examination, the characteristics of the Leo A Cepheids appear to be the natural extension of the classical Cepheid period-luminosity relations to low metallicity, rather than coming from a large population of anomalous Cepheids. We demonstrate that the periods and luminosities are consistent with the expected values of low-metallicity blue helium-burning stars (BHeBs), which populate the instability strip at lower luminosities than do higher-metallicity BHeBs.

  9. Physical explanation of the periodic table.

    Science.gov (United States)

    Ostrovsky, V N

    2003-05-01

    The Periodic Table of the elements, the most important generalization in chemistry, is often considered as a representative special case in the study of the relation between chemistry and physics. Its quantum interpretation was initiated, but not completed, by Niels Bohr. In this paper, post-Bohr conceptual developments are discussed from historical and epistemological points of view. The difference between high-precision numerical calculations for individual atoms and the theory of the periodic system as a whole is emphasized. Periodic laws met in Nature are not restricted to the chemical Periodic Table. A comparative study of these laws makes it possible to single out essential features that define the particular pattern of periodicity. It is shown that the periodic system of neutral ground state atoms now has a firm nonempirical quantum-theoretical basis. Alternative approaches, based on group theory and other mathematical schemes, are briefly discussed. It is argued that, while quantum theory is capable of fully accurate calculations for relatively simple atoms or molecular objects, the complexity of polyatomic molecules and chemical reactions guarantees the flourishing of chemistry as a separate scientific discipline.

  10. Periodic motions and resonances of impact oscillators

    Science.gov (United States)

    Dyskin, Arcady V.; Pasternak, Elena; Pelinovsky, Efim

    2012-06-01

    Bilinear oscillators - the oscillators whose springs have different stiffnesses in compression and tension - model a wide range of phenomena. A limiting case of bilinear oscillator with infinite stiffness in compression - the impact oscillator - is studied here. We investigate a special set of impact times - the eigenset, which corresponds to the solution of the homogeneous equation, i.e. the oscillator without the driving force. We found that this set and its subsets are stable with respect to variation of initial conditions. Furthermore, amongst all periodic sets of impact times with the period commensurate with the period of driving force, the eigenset is the only one which can support resonances, in particular the multi-'harmonic' resonances. Other resonances should produce non-periodic sets of impact times. This funding indicates that the usual simplifying assumption [e.g., S.W. Shaw, P.J. Holmes, A periodically forced piecewise linear oscillator, Journal of Sound and Vibration 90 (1983) 129-155] that the times between impacts are commensurate with the period of the driving force does not always hold. We showed that for the first sub-'harmonic resonance' - the resonance achieved on a half frequency of the main resonance - the set of impact times is asymptotically close to the eigenset. The envelope of the oscillations in this resonance increases as a square root of time, opposite to the linear increase characteristic of multi-'harmonic' resonances.

  11. Large Format Radiographic Imaging

    Energy Technology Data Exchange (ETDEWEB)

    J. S. Rohrer; Lacey Stewart; M. D. Wilke; N. S. King; S. A Baker; Wilfred Lewis

    1999-08-01

    Radiographic imaging continues to be a key diagnostic in many areas at Los Alamos National Laboratory (LANL). Radiographic recording systems have taken on many form, from high repetition-rate, gated systems to film recording and storage phosphors. Some systems are designed for synchronization to an accelerator while others may be single shot or may record a frame sequence in a dynamic radiography experiment. While film recording remains a reliable standby in the radiographic community, there is growing interest in investigating electronic recording for many applications. The advantages of real time access to remote data acquisition are highly attractive. Cooled CCD camera systems are capable of providing greater sensitivity with improved signal-to-noise ratio. This paper begins with a review of performance characteristics of the Bechtel Nevada large format imaging system, a gated system capable of viewing scintillators up to 300 mm in diameter. We then examine configuration alternatives in lens coupled and fiber optically coupled electro-optical recording systems. Areas of investigation include tradeoffs between fiber optic and lens coupling, methods of image magnification, and spectral matching from scintillator to CCD camera. Key performance features discussed include field of view, resolution, sensitivity, dynamic range, and system noise characteristics.

  12. Formation feedback control of UAV flight

    Science.gov (United States)

    Stegall, Stephen

    This thesis is a study of formation control with autonomous unmanned aerial vehicles using the formation as feedback. There is also an investigation of formation methods presenting insight into different algorithms for formations. A rigid formation is achieved using a proportional-derivative virtual structure with a formation feedback controller. There is an emphasis on stick controlled aerodynamics. The rigid formation is verified by a simulation of a longitudinal model. Formation control ideas are presented for rigid formations.

  13. Connecting Solubility, Equilibrium, and Periodicity in a Green, Inquiry Experiment for the General Chemistry Laboratory

    Science.gov (United States)

    Cacciatore, Kristen L.; Amado, Jose; Evans, Jason J.; Sevian, Hannah

    2008-01-01

    We present a novel first-year chemistry laboratory experiment that connects solubility, equilibrium, and chemical periodicity concepts. It employs a unique format that asks students to replicate experiments described in different sample lab reports, each lacking some essential information, rather than follow a scripted procedure. This structure is…

  14. Periodic-Orbit Bifurcation and Shell Structure in Reflection-Asymmetric Deformed Cavity

    OpenAIRE

    Sugita, A.; Arita, K.; Matsuyanagi, K.

    1997-01-01

    Shell structure of the single-particle spectrum for reflection-asymmetric deformed cavity is investigated. Remarkable shell structure emerges for certain combinations of quadrupole and octupole deformations. Semiclassical periodic-orbit analysis indicates that bifurcation of equatorial orbits plays an important role in the formation of this new shell structure.

  15. A warm and poorly ventilated deep Arctic Mediterranean during the last glacial period

    NARCIS (Netherlands)

    Thornalley, D.J.R.; Bauch, H.A.; Gebbie, G.; Guo, W.; Ziegler, M.; Bernasconi, S.M.; Barker, S.; Skinner, L.C.; Yu, J.

    2015-01-01

    Changes in the formation of dense water in the Arctic Ocean and Nordic Seas [the "Arctic Mediterranean" (AM)] probably contributed to the altered climate of the last glacial period. We examined past changes in AM circulation by reconstructing radiocarbon ventilation ages of the deep Nordic Seas over

  16. Periodic Table Target: A Game that Introduces the Biological Significance of Chemical Element Periodicity

    Science.gov (United States)

    Sevcik, Richard S.; McGinty, Ragan L.; Schultz, Linda D.; Alexander, Susan V.

    2008-01-01

    Periodic Table Target, a game for middle school or high school students, familiarizes students with the form of the periodic table and the biological significance of different elements. The Periodic Table Target game board is constructed as a class project, and the game is played to reinforce the content. Students are assigned several elements…

  17. Period, Place and Mental Space: Using Historical Scholarship to Develop Year 7 Pupils' Sense of Period

    Science.gov (United States)

    Smith, Dan

    2014-01-01

    What is a sense of period? And how can pupils' sense of period be developed? Questions such as these have troubled history teachers for many years, often revolving around debates over the role played by empathy and imagination in coming to know a period on its own terms. Rather than adopt a comparative approach, Dan Smiths decided in his teaching…

  18. Auditory sustained field responses to periodic noise

    Directory of Open Access Journals (Sweden)

    Keceli Sumru

    2012-01-01

    Full Text Available Abstract Background Auditory sustained responses have been recently suggested to reflect neural processing of speech sounds in the auditory cortex. As periodic fluctuations below the pitch range are important for speech perception, it is necessary to investigate how low frequency periodic sounds are processed in the human auditory cortex. Auditory sustained responses have been shown to be sensitive to temporal regularity but the relationship between the amplitudes of auditory evoked sustained responses and the repetitive rates of auditory inputs remains elusive. As the temporal and spectral features of sounds enhance different components of sustained responses, previous studies with click trains and vowel stimuli presented diverging results. In order to investigate the effect of repetition rate on cortical responses, we analyzed the auditory sustained fields evoked by periodic and aperiodic noises using magnetoencephalography. Results Sustained fields were elicited by white noise and repeating frozen noise stimuli with repetition rates of 5-, 10-, 50-, 200- and 500 Hz. The sustained field amplitudes were significantly larger for all the periodic stimuli than for white noise. Although the sustained field amplitudes showed a rising and falling pattern within the repetition rate range, the response amplitudes to 5 Hz repetition rate were significantly larger than to 500 Hz. Conclusions The enhanced sustained field responses to periodic noises show that cortical sensitivity to periodic sounds is maintained for a wide range of repetition rates. Persistence of periodicity sensitivity below the pitch range suggests that in addition to processing the fundamental frequency of voice, sustained field generators can also resolve low frequency temporal modulations in speech envelope.

  19. Pseudo-periodic partitions of biological sequences.

    Science.gov (United States)

    Li, Lugang; Jin, Renchao; Kok, Poh-Lin; Wan, Honghui

    2004-02-12

    Algorithm development for finding typical patterns in sequences, especially multiple pseudo-repeats (pseudo-periodic regions), is at the core of many problems arising in biological sequence and structure analysis. In fact, one of the most significant features of biological sequences is their high quasi-repetitiveness. Variation in the quasi-repetitiveness of genomic and proteomic texts demonstrates the presence and density of different biologically important information. It is very important to develop sensitive automatic computational methods for the identification of pseudo-periodic regions of sequences through which we can infer, describe and understand biological properties, and seek precise molecular details of biological structures, dynamics, interactions and evolution. We develop a novel, powerful computational tool for partitioning a sequence to pseudo-periodic regions. The pseudo-periodic partition is defined as a partition, which intuitively has the minimal bias to some perfect-periodic partition of the sequence based on the evolutionary distance. We devise a quadratic time and space algorithm for detecting a pseudo-periodic partition for a given sequence, which actually corresponds to the shortest path in the main diagonal of the directed (acyclic) weighted graph constructed by the Smith-Waterman self-alignment of the sequence. We use several typical examples to demonstrate the utilization of our algorithm and software system in detecting functional or structural domains and regions of proteins. A big advantage of our software program is that there is a parameter, the granularity factor, associated with it and we can freely choose a biological sequence family as a training set to determine the best parameter. In general, we choose all repeats (including many pseudo-repeats) in the SWISS-PROT amino acid sequence database as a typical training set. We show that the granularity factor is 0.52 and the average agreement accuracy of pseudo-periodic partitions

  20. Periodic differential equations an introduction to Mathieu, Lamé, and allied functions

    CERN Document Server

    Arscott, Felix M; Stark, M; Ulam, S

    1964-01-01

    Periodic Differential Equations: An Introduction to Mathieu, Lamé, and Allied Functions covers the fundamental problems and techniques of solution of periodic differential equations. This book is composed of 10 chapters that present important equations and the special functions they generate, ranging from Mathieu's equation to the intractable ellipsoidal wave equation.This book starts with a survey of the main problems related to the formation of periodic differential equations. The subsequent chapters deal with the general theory of Mathieu's equation, Mathieu functions of integral order, and

  1. What Determines Star Formation Rates?

    Science.gov (United States)

    Evans, Neal John

    2017-06-01

    The relations between star formation and gas have received renewed attention. We combine studies on scales ranging from local (within 0.5 kpc) to distant galaxies to assess what factors contribute to star formation. These include studies of star forming regions in the Milky Way, the LMC, nearby galaxies with spatially resolved star formation, and integrated galaxy studies. We test whether total molecular gas or dense gas provides the best predictor of star formation rate. The star formation ``efficiency," defined as star formation rate divided by mass, spreads over a large range when the mass refers to molecular gas; the standard deviation of the log of the efficiency decreases by a factor of three when the mass of relatively dense molecular gas is used rather than the mass of all the molecular gas. We suggest ways to further develop the concept of "dense gas" to incorporate other factors, such as turbulence.

  2. Numerical Simulation of Cylindrical Solitary Waves in Periodic Media

    KAUST Repository

    Quezada de Luna, Manuel

    2013-07-14

    We study the behavior of nonlinear waves in a two-dimensional medium with density and stress relation that vary periodically in space. Efficient approximate Riemann solvers are developed for the corresponding variable-coefficient first-order hyperbolic system. We present direct numerical simulations of this multiscale problem, focused on the propagation of a single localized perturbation in media with strongly varying impedance. For the conditions studied, we find little evidence of shock formation. Instead, solutions consist primarily of solitary waves. These solitary waves are observed to be stable over long times and to interact in a manner approximately like solitons. The system considered has no dispersive terms; these solitary waves arise due to the material heterogeneity, which leads to strong reflections and effective dispersion.

  3. Hidden magnetism in periodically modulated one dimensional dipolar fermions

    Science.gov (United States)

    Fazzini, S.; Montorsi, A.; Roncaglia, M.; Barbiero, L.

    2017-12-01

    The experimental realization of time-dependent ultracold lattice systems has paved the way towards the implementation of new Hubbard-like Hamiltonians. We show that in a one-dimensional two-components lattice dipolar Fermi gas the competition between long range repulsion and correlated hopping induced by periodically modulated on-site interaction allows for the formation of hidden magnetic phases, with degenerate protected edge modes. The magnetism, characterized solely by string-like nonlocal order parameters, manifests in the charge and/or in the spin degrees of freedom. Such behavior is enlighten by employing Luttinger liquid theory and numerical methods. The range of parameters for which hidden magnetism is present can be reached by means of the currently available experimental setups and probes.

  4. Design and fabrication of Ni nanowires having periodically hollow nanostructures

    Science.gov (United States)

    Sada, Takao; Fujigaya, Tsuyohiko; Nakashima, Naotoshi

    2014-09-01

    We propose a concept for the design and fabrication of metal nanowires having periodically hollow nanostructures inside the pores of an anodic aluminum oxide (AAO) membrane using a sacrificial metal. In this study, nickel (Ni) and silver (Ag) were used as the base metal and the sacrificial metal, respectively. Alternating an applied potential between -0.4 and -1.0 V provided alternatively deposited Ni and Ag segments in a Ni-Ag `barcode' nanowire with a diameter of 18 or 35 nm. After etching away the Ag segments, we fabricated Ni nanowires with nanopores of 12 +/- 5.3 nm. Such nanostructure formation is explained by the formation of a Ni shell layer over the surface of the Ag segments due to the strong affinity of Ni2+ for the interior surfaces of AAO. The Ni shell layer allows the Ni segments to remain even after dissolution of the Ag segments. Because the electroplating conditions can be easily controlled, we could carefully adjust the size and pitch of the periodically hollow nanospaces. We also describe a method for the fabrication of Ni nanorods by forming an Ag shell instead of a Ni shell on the Ni-Ag barcode nanowire, in which the interior of the AAO surfaces was modified with a compound bearing a thiol group prior to electroplating.We propose a concept for the design and fabrication of metal nanowires having periodically hollow nanostructures inside the pores of an anodic aluminum oxide (AAO) membrane using a sacrificial metal. In this study, nickel (Ni) and silver (Ag) were used as the base metal and the sacrificial metal, respectively. Alternating an applied potential between -0.4 and -1.0 V provided alternatively deposited Ni and Ag segments in a Ni-Ag `barcode' nanowire with a diameter of 18 or 35 nm. After etching away the Ag segments, we fabricated Ni nanowires with nanopores of 12 +/- 5.3 nm. Such nanostructure formation is explained by the formation of a Ni shell layer over the surface of the Ag segments due to the strong affinity of Ni2+ for the

  5. Laser printed nano-gratings: orientation and period peculiarities

    CERN Document Server

    Stankevič, Valdemar; Bragheri, Francesca; Wang, Xuewen; Gamaly, Eugene G; Osellame, Roberto; Juodkazis, Saulius

    2016-01-01

    Understanding of material behaviour at nanoscale under intense laser excitation is becoming critical for future application of nanotechnologies. Nanograting formation by linearly polarised ultra-short laser pulses has been studied systematically in fused silica for various pulse energies at 3D laser printing/writing conditions, typically used for the industrial fabrication of optical elements. The period of the nanogratings revealed a dependence on the orientation of the scanning direction. A tilt of the nanograting wave vector at a fixed laser polarisation was also observed. The mechanism responsible for this peculiar dependency of several features of the nanogratings on the writing direction is qualitatively explained by considering the heat transport flux in the presence of a linearly polarised electric field, rather than by temporal and spatial chirp of the laser beam. The confirmed vectorial nature of the light-matter interaction opens new control of material processing with nanoscale precision.

  6. Formative Assessment as an Effective Leadership Learning Tool.

    Science.gov (United States)

    Garrett, J Matthew; Camper, Jill M

    2015-01-01

    Formative assessment can be a critical and creative practice in leadership education and significantly enhance student learning, leader development, and leadership development. This chapter seeks to frame the use of assessment as both a best practice in leadership education and as an integral component to effective leadership learning pedagogy. © 2015 Wiley Periodicals, Inc., A Wiley Company.

  7. Mesoamerica Writing at the Crossroads: The Late Formative.

    Science.gov (United States)

    Stross, Brian

    1990-01-01

    Offers an overview of Later Formative period writing in Mesoamerica, and discusses recent findings. Asserts that analysis of the iconographic context of the script reveals considerable interdependence between text and context and provides a glimpse of the importance of cosmological considerations in the display of power. Discusses the importance…

  8. Triglycerides and gallstone formation.

    Science.gov (United States)

    Smelt, A H M

    2010-11-11

    Changes in bile acid (BA) metabolism and gallbladder function are critical factors in the pathogenesis of gallstones. Patients with hypertriglyceridemia (HTG) - often overweight and insulin resistant - are at risk for gallstone disease. The question arises whether HTG itself contributes to gallstone formation or whether gallstone disease only associates with this disorder. Triglycerides are formed in response to fluxes of non-esterified fatty acids and glucose. Hypertriglyceridemia results from either overproduction of triglycerides by the liver, impaired lipolysis or a combination of both. Hyperinsulinemia, as observed in the insulin resistant state, stimulates very low-density lipoprotein (VLDL)-triglyceride synthesis. Peroxisome proliferator-activated receptors (PPARs), liver X receptors (LXRs), farnesoid X receptor (FXR) and hepatocyte nuclear factor 4α (HNF4α) are the nuclear receptors involved in the regulation of lipogenesis. Microsomal triglyceride transfer protein (MTP) is involved in the production of VLDL and its activation is also under control of transcription factors as FXR and Forkhead box-O1 (FoxO1). Triglyceride and BA metabolism are linked. There is an inverse relationship between bile acid fluxes and pool size and VLDL production and SHP (small heterodimer partner) and FXR are the link between BAs and TG metabolism. BAs are also ligands for FXR and G-protein-coupled receptors, such as TGR5. FXR activation by BAs suppresses the expression of MTP, transcription factor sterol regulatory element binding protein (SREBP)-1c and other lipogenic genes. LXRs stimulate lipogenesis whereas FXRs inhibit the metabolic process. Synthesis of BAs from cholesterol occurs either via the classical pathway (7α-hydroxylation of cholesterol; CYP7A1) or via the alternate pathway (CYP39A1 or CYP7B1). BAs induce FXR, which inhibits CYP7A1 transcription by activation of SHP and inhibition of HNF4α transactivation. Bile composition (supersaturation with cholesterol

  9. Medicine in Balkans during the Roman Period.

    Science.gov (United States)

    Baykan, Daniş

    2017-08-04

    The aim of this study is to investigate the archaeological finds to enlighten the medical methods of treatments and operations applied in Balkans during Roman Period. Some independent local and regional find groups, taken from existing publications will be grouped together and a holistic point-of-view will be taken against medicine in Balkan Geography during Roman Period. Due to basic differences it contained, the data before Roman Period are excluded. Most of Greece and Aegean Islands are also excluded since the topic selected is "Medicine of Roman Period." Greece and Aegean Islands should be evaluated in another study in connection with West Anatolia which is closer than the Balkan Geography in terms of social relations. The spread of medical tools in Balkans during Roman Period is concentrated around military garrisons, and in settlements built around military pathways, and in settlements containing an amphitheater associated with gladiators. This spread is verified by the studies on Bulgaria in general. The data is also compatible with the assertion suggesting that the amount of application of pharmaceutical treatment increases when one moves away from the military centres.

  10. The Discrete Beverton-Holt Model with Periodic Harvesting in a Periodically Fluctuating Environment

    Directory of Open Access Journals (Sweden)

    Ziyad AlSharawi

    2010-01-01

    Full Text Available We investigate the effect of constant and periodic harvesting on the Beverton-Holt model in a periodically fluctuating environment. We show that in a periodically fluctuating environment, periodic harvesting gives a better maximum sustainable yield compared to constant harvesting. However, if one can also fix the environment, then constant harvesting in a constant environment can be a better option, especially for sufficiently large initial populations. Also, we investigate the combinatorial structure of the periodic sequence of carrying capacities and its effect on the maximum sustainable yield. Finally, we leave some questions worth further investigations.

  11. Radiolysis of confined water: molecular hydrogen formation

    Energy Technology Data Exchange (ETDEWEB)

    Rotureau, P.; Renault, J.P.; Mialocq, J.C. [CEA/Saclay, DSM/DRECAM/SCM/URA 331 CNRS, 91191 Gif-sur-Yvette Cedex (France); Lebeau, B.; Patarin, J. [Laboratoire de Materiaux a Porosite Controlee, UMR CNRS 7016, ENSCMu-UHA, 3, Rue Alfred Werner, 68093 Mulhouse Cedex (France)

    2005-07-11

    The formation of molecular hydrogen in the radiolysis of water confined in nanoscale pores of well-characterised porous silica glasses and mesoporous molecular sieves (MCM-41) is examined. The comparison of dihydrogen formation by irradiation of both materials, dry and hydrated, shows that a large part of the H{sub 2} comes from the surface of the material. The radiolytic yields, G(H{sub 2})=(3{+-}0.5) x 10{sup -7} mol J{sup -1}, calculated using the total energy deposited in the material and the water, are only slightly affected by the degree of hydration of the material and by the pore size. These yields are also not modified by the presence of hydroxyl radical scavengers. This observation proves that the back reaction between H{sub 2} and HO{sup .} is inoperative in such confined environments. Furthermore, the large amount of H{sub 2} produced in the presence of different concentrated scavengers of the hydrated electron and its precursor suggests that these two species are far from being the only species responsible for the H{sub 2} formation. Our results show that the radiolytic phenomena that occur in water confined in nanoporous silica are dramatically different to those in bulk water, suggesting the need to investigate further the chemical reactivity in this type of environment. (Abstract Copyright [2005], Wiley Periodicals, Inc.)

  12. On a spectral criterion for almost periodicity of solutions of periodic evolution equations

    Directory of Open Access Journals (Sweden)

    Toshiki Naito

    1999-01-01

    Full Text Available This paper is concerned with equations of the form: $u'=A(tu + f(t$, where $A(t$ is (unbounded periodic linear operator and f is almost periodic. We extend a central result on the spectral criteria for almost periodicity of solutions of evolution equations to some classes of periodic equations which says that if $u$ is a bounded uniformly continuous mild solution and $P$ is the monodromy operator, then their spectra satisfy $e^{i sp_{AP(u}}\\subset \\sigma(P\\cap S^1$, where $S^1$ is the unit circle. This result is then applied to find almost periodic solutions to the above­mentioned equations. In particular, parabolic and functional differential equations are considered. Existence conditions for almost periodic and quasi­periodic solutions are discussed.

  13. Infinte Periodic Structure of Lightweight Elements

    DEFF Research Database (Denmark)

    Domadiya, Parthkumar Gandalal; Andersen, Lars Vabbersgaard; Sorokin, Sergey

    2013-01-01

    . Furthermore, lightweight building elements are typically periodic structures that behave as filters for sound propagation within certain frequency ranges (stop bands), thus only allowing transmission within the pass bands. Hence, traditional methods based on statistical energy analysis cannot be used...... for proper dynamic assessment of lightweight buildings. Instead, this paper discusses and compares the use of finite element analysis and a wave approach based on Floquet theory. The present analysis has focus on the effect of periodicity on vibration transmission within semi-infinite beam structures. Two...... models of a semi-infinite Euler-Bernoulli and Timoshenko beam structure with periodic variation of the cross-sectional properties are analyzed. In case of the Euler-Bernoulli beam, vibrational behavior is studied in two dimensions by finite element analysis and Floquet theory. Wave propagation within...

  14. Policy Uncertainty, Investment and Commitment Periods

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2007-07-01

    Today's investment decisions in key sectors such as energy, forestry or transport have significant impacts on the levels of greenhouse gas (GHG) emissions over the coming decades. Given the economic and environmental long-term implications of capital investment and retirement, a climate mitigation regime should aim to encourage capital investment in climate-friendly technologies. Many factors affect technology choice and the timing of investment, including investor expectations about future prices and policies. Recent international discussions have focused on the importance of providing more certainty about future climate policy stringency. The design of commitment periods can play a role in creating this environment. This paper assesses how the length of commitment periods influences policy uncertainty and investment decisions. In particular, the paper analyses the relationship between commitment period length and near term investment decisions in climate friendly technology.

  15. Intermittence and roughening of periodic elastic media.

    Science.gov (United States)

    Seppälä, E T; Alava, M J; Duxbury, P M

    2001-03-01

    We analyze intermittence and roughening of an elastic interface or domain wall pinned in a periodic potential, in the presence of random-bond disorder in 1+1 and 2+1 dimensions. Though the ensemble average behavior is smooth, the typical behavior of a large sample is intermittent, and does not self-average to a smooth behavior. Instead, large fluctuations occur in the mean location of the interface and the onset of interface roughening is via an extensive fluctuation which leads to a jump in the roughness of order lambda, the period of the potential. Analytical arguments based on extreme statistics are given for the number of the minima of the periodicity visited by the interface and for the roughening crossover, which is confirmed by extensive exact ground state calculations.

  16. Planar glass devices for efficient periodic poling

    DEFF Research Database (Denmark)

    Fage-Pedersen, Jacob; Jacobsen, Rune Shim; Kristensen, Martin

    2005-01-01

    We demonstrate that frequency-converting devices of high quality can be realised with glass poling. The devices, made with silica-on-silicon technology, are poled with periodic, embedded electrodes, and used for second-harmonic generation. We obtain precise control of the quasi phase-matching wav......We demonstrate that frequency-converting devices of high quality can be realised with glass poling. The devices, made with silica-on-silicon technology, are poled with periodic, embedded electrodes, and used for second-harmonic generation. We obtain precise control of the quasi phase......-matching wavelength and bandwidth, and a normalised conversion efficiency of 1.4×10-3 %/W/cm2 which, to our knowledge, is the highest obtained so far with periodic glass poling....

  17. Periodic and Chaotic Flapping of Insectile Wings

    CERN Document Server

    Huang, Yangyang

    2015-01-01

    Insects use flight muscles attached at the base of the wings to produce impressive wing flapping frequencies. The maximum power output of these flight muscles is insufficient to maintain such wing oscillations unless there is good elastic storage of energy in the insect flight system. Here, we explore the intrinsic self-oscillatory behavior of an insectile wing model, consisting of two rigid wings connected at their base by an elastic torsional spring. We study the wings behavior as a function of the total energy and spring stiffness. Three types of behavior are identified: end-over-end rotation, chaotic motion, and periodic flapping. Interestingly, the region of periodic flapping decreases as energy increases but is favored as stiffness increases. These findings are consistent with the fact that insect wings and flight muscles are stiff. They further imply that, by adjusting their muscle stiffness to the desired energy level, insects can maintain periodic flapping mechanically for a range of operating condit...

  18. Periodic solutions of Volterra integral equations

    Directory of Open Access Journals (Sweden)

    M. N. Islam

    1988-01-01

    Full Text Available Consider the system of equationsx(t=f(t+∫−∞tk(t,sx(sds,           (1andx(t=f(t+∫−∞tk(t,sg(s,x(sds.       (2Existence of continuous periodic solutions of (1 is shown using the resolvent function of the kernel k. Some important properties of the resolvent function including its uniqueness are obtained in the process. In obtaining periodic solutions of (1 it is necessary that the resolvent of k is integrable in some sense. For a scalar convolution kernel k some explicit conditions are derived to determine whether or not the resolvent of k is integrable. Finally, the existence and uniqueness of continuous periodic solutions of (1 and (2 are btained using the contraction mapping principle as the basic tool.

  19. Periodic Variations in DQ Herculis Stars

    Science.gov (United States)

    Bless, Robert

    1991-07-01

    The DQ Herculis Stars are cataclysmic variables showing rapid, strictly periodic luminosity variations at either optical or X-ray wavelengths, and usually both. The periods range from 33 sec in AE AQR through 71 sec in DQ Her to 18690 sec in TV Col. The cataclysmic variables are all close binary stars consisting of a late-type star transferring mass to its companion white dwarf star. The white dwarf in the DQ Her stars is magnetized. The periodicities of the DQ Her stars are caused by rotation of the magnetized, acreting white dwarf. We propose to observe the DQ Her stars at ultraviolet wavelengths using the high speed photometer on the space telescope. The purpose of the observations is to investigate the physics of accretion onto compact stars. Revision History: Prepared for future cycles submission--BJW 4/22/92; Cycle 3 to cycle 2, PRISM to SINGLE--BJW 8/27/92;

  20. Electromagnetic Radiation of Electrons in Periodic Structures

    CERN Document Server

    Potylitsyn, Alexander Petrovich

    2011-01-01

    Periodic magnetic structures (undulators) are widely used in accelerators to generate monochromatic undulator radiation (UR) in the range from far infrared to the hard X-ray region. Another periodic crystalline structure is used to produce quasimonochromatic polarized photon beams via the coherent bremsstrahlung mechanism (CBS). Due to such characteristics as monochromaticity, polarization and adjustability, these types of radiation is of large interest for applied and basic research of accelerator-emitted radiation. The book provides a detailed overview of the fundamental principles behind electromagnetic radiation emitted from accelerated charged particles (e.g. UR, CBS, radiation of fast electrons in Laser flash fields) as well as a unified description of relatively new radiation mechanisms which attracted great interest in recent years. This are the so-called polarization radiation excited by the Coulomb field of incident particles in periodic structures, parametric X-rays, resonant transition radiation a...

  1. Effective propagation in a perturbed periodic structure

    Science.gov (United States)

    Maurel, Agnès; Pagneux, Vincent

    2008-08-01

    In a recent paper [D. Torrent, A. Hakansson, F. Cervera, and J. Sánchez-Dehesa, Phys. Rev. Lett. 96, 204302 (2006)] inspected the effective parameters of a cluster containing an ensemble of scatterers with a periodic or a weakly disordered arrangement. A small amount of disorder is shown to have a small influence on the characteristics of the acoustic wave propagation with respect to the periodic case. In this Brief Report, we inspect further the effect of a deviation in the scatterer distribution from the periodic distribution. The quasicrystalline approximation is shown to be an efficient tool to quantify this effect. An analytical formula for the effective wave number is obtained in one-dimensional acoustic medium and is compared with the Berryman result in the low-frequency limit. Direct numerical calculations show a good agreement with the analytical predictions.

  2. Established meteor shower activity periods and orbits

    Science.gov (United States)

    Roggemans, Paul

    2017-02-01

    The CAMS dataset of 111233 orbits collected in the period 2010-2013 has been checked to verify the online data of the IAU meteor shower list. The activity periods for all meteor streams detected in CAMS data has been derived from the solar longitudes of the individual orbits that were associated with the meteor stream. For meteor showers that were absent in the CAMS data, mainly daylight meteor streams, CMOR data has been used to complete the information. To make future associations easier and to avoid mixing up shower data, the official naming and IAU code with the orbital elements are listed in this contribution.

  3. Critical period revisited: impact on vision.

    Science.gov (United States)

    Morishita, Hirofumi; Hensch, Takao K

    2008-02-01

    Neural circuits are shaped by experience in early postnatal life. The permanent loss of visual acuity (amblyopia) and anatomical remodeling within primary visual cortex following monocular deprivation is a classic example of critical period development from mouse to man. Recent work in rodents reveals a residual subthreshold potentiation of open eye response throughout life. Resetting excitatory-inhibitory balance or removing molecular 'brakes' on structural plasticity may unmask the potential for recovery of function in adulthood. Novel pharmacological or environmental interventions now hold great therapeutic promise based on a deeper understanding of critical period mechanisms.

  4. Mathematics of Periodic Tables for Benzenoid Hydrocarbons.

    Science.gov (United States)

    Dias, Jerry Ray

    2007-01-01

    The upper and lower bounds for invariants of polyhex systems based on the Harary and Harborth inequalities are studied. It is shown that these invariants are uniquely correlated by the Periodic Table for Benzenoid Hydrocarbons. A modified periodic table for total resonant sextet (TRS) benzenoids based on the invariants of Ds and r(empty) is presented; Ds is the number of disconnections among the empty rings for fused TRS benzenoid hydrocarbons. This work represents a contribution toward deciphering the topological information content of benzenoid formulas.

  5. Short period tidal variations of earth rotation

    Science.gov (United States)

    Yoder, C. F.; Williams, J. G.; Parke, M. E.; Dickey, J. O.

    1981-01-01

    It is explained that the tidal deformation of the earth's polar moment of inertia by the moon and sun cause periodic variations in rotation. The short period oscillations give rise to a meter-sized, diurnal signature in the lunar laser ranging data obtained at McDonald Observatory. A solution is given for the scale parameter k/C at fortnightly and monthly tidal frequencies. The results are compared with those obtained by other investigators and with a theoretical estimate which includes the effect of oceans and a decoupled fluid core.

  6. Reconstruction of periodic signals using neural networks

    Directory of Open Access Journals (Sweden)

    José Danilo Rairán Antolines

    2014-01-01

    Full Text Available In this paper, we reconstruct a periodic signal by using two neural networks. The first network is trained to approximate the period of a signal, and the second network estimates the corresponding coefficients of the signal's Fourier expansion. The reconstruction strategy consists in minimizing the mean-square error via backpro-pagation algorithms over a single neuron with a sine transfer function. Additionally, this paper presents mathematical proof about the quality of the approximation as well as a first modification of the algorithm, which requires less data to reach the same estimation; thus making the algorithm suitable for real-time implementations.

  7. Numerical study of two disks settling in an Oldroyd-B fluid: From periodic interaction to chaining

    Science.gov (United States)

    Pan, Tsorng-Whay; Glowinski, Roland

    2017-12-01

    In this article, we present a numerical study of the dynamics of two disks sedimenting in a narrow vertical channel filled with an Oldroyd-B fluid. Two kinds of particle dynamics are observed: (i) a periodic interaction between the two disks, and (ii) the formation of a two-disk chain. For the periodic interaction of the two disks, two different motions are observed: (a) the two disks stay far apart and interact periodically, and (b) the two disks interact closely and then far apart in a periodic way, like the drafting, kissing, and tumbling of two disks sedimenting in a Newtonian fluid, due to a weak elastic force. Concerning the formation of a two-disk chain occurring at higher values of the elasticity number, either a tilted chain or a vertical chain is observed. Our simulations show that, as expected, the values of the elasticity and Mach numbers are the determining factors concerning the particle chain formation and its orientation.

  8. [Peculiarities of sexual behavior of female rats with hyperandrogenia in pubertal and postpubertal periods].

    Science.gov (United States)

    Nosenko, N D; Lymarieva, A A

    2013-01-01

    The parameters of female and male sexual behavior in 3- and 6- month old female rats which were exposed to an androgen excess (subcutaneous implantation of Silastic capsules containing 5 mg of crystalline testosterone) from the beginning of pubertal period (at the age of 35 days), or within postpubertal period (at the age of 4 months). Hyperandrogenia in pubertal period had no effect on female sexual behavior formation, but it led to appearance of male behavior components in 100% of animals. In female rats which were implanted with testosterone capsules in postpubertal period, sexual disturbances were more pronounced and were characterized by masculinization and defeminization, which was due to a higher degree of androgenic saturation. The data obtained suggest a leading role of hyperandrogenemia in the pathogenesis of sexual behavior disturbances in female rats in different periods of individual development.

  9. Satellite formation flying relative dynamics, formation design, fuel optimal maneuvers and formation maintenance

    CERN Document Server

    Wang, Danwei; Poh, Eng Kee

    2017-01-01

    This book systematically describes the concepts and principles for multi-satellite relative motion, passive and near passive formation designs, trajectory planning and control for fuel optimal formation maneuvers, and formation flying maintenance control design. As such, it provides a sound foundation for researchers and engineers in this field to develop further theories and pursue their implementations. Though satellite formation flying is widely considered to be a major advance in space technology, there are few systematic treatments of the topic in the literature. Addressing that gap, the book offers a valuable resource for academics, researchers, postgraduate students and practitioners in the field of satellite science and engineering.

  10. Planet formation around millisecond pulsars

    Science.gov (United States)

    Banit, Menashe; Ruderman, Malvin; Shaham, Jacob

    1993-01-01

    We present a model for the formation of planets in circular orbits around millisecond pulsars. We propose that the planets originate from a circumbinary excretion disk around a binary millisecond pulsar and show how physical conditions in such a disk lead to the eventual formation of planets.

  11. Bundle Formation in Biomimetic Hydrogels

    NARCIS (Netherlands)

    Jaspers, Maarten; Pape, A C H; Voets, Ilja K; Rowan, Alan E; Portale, Giuseppe; Kouwer, Paul H J

    2016-01-01

    Bundling of single polymer chains is a crucial process in the formation of biopolymer network gels that make up the extracellular matrix and the cytoskeleton. This bundled architecture leads to gels with distinctive properties, including a large-pore-size gel formation at very low concentrations and

  12. Pathogenesis of postoperative adhesion formation

    NARCIS (Netherlands)

    Hellebrekers, B.W.J.; Kooistra, T.

    2011-01-01

    Background: Current views on the pathogenesis of adhesion formation are based on the "classical concept of adhesion formation", namely that a reduction in peritoneal fibrinolytic activity following peritoneal trauma is of key importance in adhesion development. Methods: A non-systematic literature

  13. Tooth formation - delayed or absent

    Science.gov (United States)

    ... tooth formation; Teeth - delayed or absent formation Images Tooth anatomy Development of baby teeth Development of permanent teeth References ... MO: Elsevier Mosby; 2016:chap 19. Tinanoff N. Development and developmental anomalies of the teeth. In: Kliegman RM, ... NIH MedlinePlus Magazine Read more ...

  14. Identity formation in multiparty negotiations

    NARCIS (Netherlands)

    Swaab, R; Postmes, T.; Spears, R.

    Based on the recently proposed Interactive Model of Identity Formation, we examine how top-down deductive and bottom-up inductive identity formations influence intentions and behaviour in multiparty negotiations. Results show that a shared identity can be deduced from the social context through

  15. Medical Periodicals Control—Evolution into Networking

    Science.gov (United States)

    Johnson, Millard F.; Stucki, Loretta; Igielnik, Simon

    1982-01-01

    The PHILSOM system for periodicals control evolved from a batch program for the management of an inventory problem to a national online network using long-line and distributed computing techniques. The stages of growth from consortium development, through sharing of professional expertise, to the current state of shared resources are described. Current operation and future prospects are discussed.

  16. Slow-light vortices in periodic waveguides

    DEFF Research Database (Denmark)

    Sukhorukov, Andrey A.; Ha, Sangwoo; Desyatnikov, Anton S.

    2009-01-01

    We reveal that the reduction of the group velocity of light in periodic waveguides is generically associated with the presence of vortex energy flows. We show that the energy flows are gradually frozen for slow-light at the Brillouin zone edge, whereas vortices persist for slow-light states havin...

  17. Teaching the Hitler Period: History and Morality.

    Science.gov (United States)

    Mork, Gordon R.

    1980-01-01

    Outlines six approaches used in a university history course which address the problems of teaching the Hitler period. The assumption underlying all the approaches is that Americans are not entirely different from Germans and that they may be faced with similar moral choices. The approaches avoid the didactic moralism often taught about this era.…

  18. Duplicated Publication Fundamentals for Student Periodicals.

    Science.gov (United States)

    Columbia Scholastic Press Association, New York, NY.

    This handbook provides the 1973 basic principles of the Columbia Scholastic Press Association for determining the quality of high school and college student periodicals which are intended for duplication. The handbook begins with an explanation of rating procedures used in this evaluation and then provides sample scorebooks for student newspapers,…

  19. Mental Illness in the Peripartum Period

    Science.gov (United States)

    Ostler, Teresa

    2009-01-01

    Women are particularly vulnerable in the peripartum period for either developing a mental illness or suffering symptom exacerbation. These illnesses are often experienced covertly, however, and women may not seek out professional help, even though their symptoms may be seriously affecting their well-being and parenting. This article provides an…

  20. Reduced BOLD response to periodic visual stimulation.

    NARCIS (Netherlands)

    Parkes, L.M.; Fries, P.; Kerskens, C.M.; Norris, D.G.

    2004-01-01

    The blood oxygenation level-dependent (BOLD) response to entrained neuronal firing in the human visual cortex and lateral geniculate nuclei was investigated. Periodic checkerboard flashes at a range of frequencies (4-20 Hz) were used to drive the visual cortex neurons into entrained oscillatory

  1. Reduced BOLD response to periodic visual stimulation

    NARCIS (Netherlands)

    Parkes, L.M.; Fries, P.; Kerskens, C.M.; Norris, D.G.

    2004-01-01

    The blood oxygenation level-dependent (BOLD) response to entrained neuronal firing in the human visual cortex and lateral geniculate nuclei was investigated. Periodic checkerboard flashes at a range of frequencies (4-20 Hz) were used to drive the visual cortex neurons into entrained oscillatory

  2. The Long Period of 2675 Tolkien

    Science.gov (United States)

    Durkee, Russell I.; Brinsfield, James W.; Hornoch, Kamil; Kuönirak, Petr

    2011-10-01

    Lightcurve measurements of 2675 Tolkien from the Shed of Science, Via Capote Observatory, and Ondrejov Observatory were taken on twenty-three nights; a period of P = 1058 ± 30 hrs, A = 0.75 ± 0.1 mag were derived.

  3. Periodic review in natural resource contracts | Mandelbaum ...

    African Journals Online (AJOL)

    Periodic contract review mechanisms, which are provisions in contracts that formally require parties to meet at particular intervals to review the terms of the contract, are mechanisms that may facilitate the process of negotiating contractual changes to accommodate changing circumstances over the term of extractive ...

  4. Better Writing: Beyond Periods and Commas

    Science.gov (United States)

    Koll, Travis J.

    2012-01-01

    Using casual language and a straightforward approach, "Better Writing: Beyond Periods and Commas" provides students with an easy-to-read and effective guide for developing their writing skills. Rather than intimidate and overwhelm novice writers with vast sets of rules, Travis Koll utilizes simple and relatable explanations and examples to…

  5. Relating Functional Groups to the Periodic Table

    Science.gov (United States)

    Struyf, Jef

    2009-01-01

    An introduction to organic chemistry functional groups and their ionic variants is presented. Functional groups are ordered by the position of their specific (hetero) atom in the periodic table. Lewis structures are compared with their corresponding condensed formulas. (Contains 5 tables.)

  6. The Different Periodic Tables of Dmitrii Mendeleev

    Science.gov (United States)

    Laing, Michael

    2008-01-01

    Between 1869 and 1905 the Russian chemist Dmitrii Mendeleev published several tables with different arrangements of the chemical elements. Four of these are compared with periodic tables by Russian scientists from 1934 and 1969. The difficulties caused by the lanthanoid elements are clearly seen in the table of 1905, which satisfactorily includes…

  7. Clustering of periodic orbits in chaotic systems

    Science.gov (United States)

    Gutkin, Boris; Osipov, Vladimir Al

    2013-01-01

    In the framework of the semiclassical approach, the universal spectral correlations in Hamiltonian systems with classical chaotic dynamics can be attributed to the systematic correlations between the actions of periodic orbits which (up to the switch in the momentum direction) pass through approximately the same points of the phase space. By considering symbolic dynamics of the system one can introduce a natural ultrametric distance between periodic orbits and organize them into clusters of orbits approaching each other in the phase space. We study the distribution of cluster sizes for the baker's map in the asymptotic limit of long trajectories. This problem is equivalent to the one of counting degeneracies in the length spectrum of the de Bruijn graphs. Based on this fact, we derive the probability P_k that k randomly chosen periodic orbits belong to the same cluster. Furthermore, we find asymptotic behaviour of the largest cluster size |C_{\\max}| and derive the probability P(t) that a random periodic orbit belongs to a cluster smaller than t|C_{\\max}| , t ∈ [0, 1].

  8. Periodic nanowire array at the crystal interface.

    Science.gov (United States)

    Nakamura, Atsutomo; Mizoguchi, Teruyasu; Matsunaga, Katsuyuki; Yamamoto, Takahisa; Shibata, Naoya; Ikuhara, Yuichi

    2013-07-23

    A dislocation in a crystalline material has dangling bonds at its core and a strong strain field in its vicinity. Consequently, the dislocation attracts solute atoms and forms a so-called Cottrell atmosphere along the dislocation. A crystalline dislocation can be used as a template to produce nanowires by selectively doping foreign atoms along the dislocation. However, control of the configuration, spacing, and density of the formed periodic nanowire array has heretofore been extremely difficult. Here we show a method for fabricating ordered, electrically conductive nanowire arrays using periodic dislocations at crystal interfaces. As a demonstration, we fabricated arrays of titanium nanowires arranged at intervals of either 13 or 90 nm and then confirmed by scanning probe microscopy that they exhibit electrical conductivity inside an insulating aluminum oxide. Significantly, we were able to precisely control nanowire periodicity by the choice of crystal orientation and/or crystal planes at the crystal interface. This simple method for the fabrication of periodic nanowire arrays of highly controlled density should be widely applicable to electrical, magnetic, and optical devices.

  9. Periodic and aperiodic plasmon lattice lasers

    NARCIS (Netherlands)

    Schokker, A.H.

    2016-01-01

    Motivated by seminal proposals for surface plasmon amplification by stimulated emission, we conduct experiments on 2D plasmonic particle arrays in waveguiding layers that provide gain. We find that purely periodic plasmonic particle systems provide lasing characteristics similar to DFB lasers, yet

  10. Six Online Periodical Databases: A Librarian's View.

    Science.gov (United States)

    Willems, Harry

    1999-01-01

    Compares the following World Wide Web-based periodical databases, focusing on their usefulness in K-12 school libraries: EBSCO, Electric Library, Facts on File, SIRS, Wilson, and UMI. Search interfaces, display options, help screens, printing, home access, copyright restrictions, database administration, and making a decision are discussed. A…

  11. Wave propagation in axially moving periodic strings

    DEFF Research Database (Denmark)

    Sorokin, Vladislav S.; Thomsen, Jon Juel

    2017-01-01

    The paper deals with analytically studying transverse waves propagation in an axially moving string with periodically modulated cross section. The structure effectively models various relevant technological systems, e.g. belts, thread lines, band saws, etc., and, in particular, roller chain drive...

  12. Theory of Periodic Conjugate Heat Transfer

    CERN Document Server

    Zudin, Yuri B

    2012-01-01

    This book presents the theory of periodic conjugate heat transfer in a detailed way. The effects of thermophysical properties and geometry of a solid body on the commonly used and experimentally determined heat transfer coefficient are analytically presented from a general point of view. The main objective of the book is a simplified description of the interaction between a solid body and a fluid as a boundary value problem of the heat conduction equation for the solid body. At the body surface, the true heat transfer coefficient is composed of two parts: the true mean value resulting from the solution of the steady state heat transfer problem and a periodically variable part, the periodic time and length to describe the oscillatory hydrodynamic effects. The second edition is extended by (i) the analysis of stability boundaries in helium flow at supercritical conditions in a heated channel with respect to the interaction between a solid body and a fluid; (ii) a periodic model and a method of heat transfer sim...

  13. Extracting Periodic Signals From Irregularly Sampled Data

    Science.gov (United States)

    Wilcox, Jaroslava Z.

    1995-01-01

    Successive approximations formed in Fourier space. Algorithm extracts periodic signals from sparse, irregularly sampled sets of measurement data. Pertains to data processed via fast Fourier transforms (FFTs). Data represents signal components with initially unknown frequencies spanning large spectral range and includes frequencies not integer multiples of minimum FFT frequency.

  14. Resonances in a periodically driven bosonic system

    Science.gov (United States)

    Quelle, Anton; Smith, Cristiane Morais

    2017-11-01

    Periodically driven systems are a common topic in modern physics. In optical lattices specifically, driving is at the origin of many interesting phenomena. However, energy is not conserved in driven systems, and under periodic driving, heating of a system is a real concern. In an effort to better understand this phenomenon, the heating of single-band systems has been studied, with a focus on disorder- and interaction-induced effects, such as many-body localization. Nevertheless, driven systems occur in a much wider context than this, leaving room for further research. Here, we fill this gap by studying a noninteracting model, characterized by discrete, periodically spaced energy levels that are unbounded from above. We couple these energy levels resonantly through a periodic drive, and discuss the heating dynamics of this system as a function of the driving protocol. In this way, we show that a combination of stimulated emission and absorption causes the presence of resonant stable states. This will serve to elucidate the conditions under which resonant driving causes heating in quantum systems.

  15. A comparison of periodic versus permanent surveys

    Science.gov (United States)

    Michael Kohl; Charles T. Scott

    2000-01-01

    Extensive forest surveys can be periodic or permanent, regional or national, can include midcycle updates or not, or use partial replacement of plots or not. Fifty-two combinations of these and other factors were evaluated, not solely on a statistical basis, but also on their perceived ability to meet various design and customer objectives. These criteria include...

  16. Period changes in ultracompact double white dwarfs

    NARCIS (Netherlands)

    Marsh, T.R.; Nelemans, G.A.

    2005-01-01

    In recent years there has been much interest in the nature of two stars, V407 Vul and RX J0806+1527, which are widely thought to be binary white dwarfs of very short orbital period, 570 and 321s, respectively. As such they should be strong sources of gravitational waves and possible ancestors of the

  17. The extraordinary spectral properties of radially periodic ...

    Indian Academy of Sciences (India)

    Since it became clear that the band structure of the spectrum of periodic Sturm Liouville operators = - (d2/d2) + () does not survive a spherically symmetric extension to Schrödinger operators = - + with () = (||) for x ∈ R d , d ∈ N ∖ { 1 } , a wealth of detailed information about the spectrum of such operators ...

  18. Periodic Solutions for Highly Nonlinear Oscillation Systems

    DEFF Research Database (Denmark)

    Ghadimi, M; Barari, Amin; Kaliji, H.D

    2012-01-01

    In this paper, Frequency-Amplitude Formulation is used to analyze the periodic behavior of tapered beam as well as two complex nonlinear systems. Many engineering structures, such as offshore foundations, oil platform supports, tower structures and moving arms, are modeled as tapered beams. The r...

  19. 7 CFR 247.16 - Certification period.

    Science.gov (United States)

    2010-01-01

    ... Agriculture Regulations of the Department of Agriculture (Continued) FOOD AND NUTRITION SERVICE, DEPARTMENT OF AGRICULTURE CHILD NUTRITION PROGRAMS COMMODITY SUPPLEMENTAL FOOD PROGRAM § 247.16 Certification period. (a... six weeks post-partum. (2) Elderly persons. For elderly persons, the State agency must establish...

  20. QS Spiral: Visualizing Periodic Quantified Self Data

    DEFF Research Database (Denmark)

    Larsen, Jakob Eg; Cuttone, Andrea; Jørgensen, Sune Lehmann

    2013-01-01

    In this paper we propose an interactive visualization technique QS Spiral that aims to capture the periodic properties of quantified self data and let the user explore those recurring patterns. The approach is based on time-series data visualized as a spiral structure. The interactivity includes ...

  1. Isomeric periodic mesoporous organosilicas with controllable properties

    NARCIS (Netherlands)

    Vercaemst, C.; Ide, I.; Friedrich, H.; de Jong, K.P.; Verpoort, F.; van der Voort, P.

    2009-01-01

    The synthesis procedure for isomeric periodic mesoporous organosilicas with E-configured ethenylene bridges was investigated using the homemade pure E-isomer of 1,2-bis(triethoxysilyl)ethene. The pH, aging temperature and the presence of cosolvents played a key role in obtaining well-ordered

  2. 31 CFR 128.22 - Periodic reports.

    Science.gov (United States)

    2010-07-01

    ... 31 Money and Finance: Treasury 1 2010-07-01 2010-07-01 false Periodic reports. 128.22 Section 128.22 Money and Finance: Treasury Regulations Relating to Money and Finance REPORTING OF INTERNATIONAL... as outstanding foreign exchange contracts, dealing positions, derivative foreign currency instruments...

  3. Ecological periodic tables for estuarine habitats

    Science.gov (United States)

    Southwood (1977; J Anim Ecol 46: 337-365) compared the situation in ecology to that in chemistry before the development of the periodic table when each fact, for example, the solubility or reactivity of a chemical element, had to be discovered independently and remembered in isol...

  4. Fourier Series The Mathematics of Periodic Phenomena

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 1; Issue 10. Fourier Series The Mathematics of Periodic Phenomena. S Thangavelu ... Author Affiliations. S Thangavelu1. Department of Mathematics and Statistics, University of New Mexico, Humanities Building 419, Albuquerque, NM 87131-1141, USA ...

  5. Periodic Solutions for Circular Restricted -Body Problems

    Directory of Open Access Journals (Sweden)

    Xiaoxiao Zhao

    2013-01-01

    Full Text Available For circular restricted -body problems, we study the motion of a sufficiently small mass point (called the zero mass point in the plane of equal masses located at the vertices of a regular polygon. By using variational minimizing methods, for some , we prove the existence of the noncollision periodic solution for the zero mass point with some fixed wingding number.

  6. Periodic health examination by Austrian general practitioners.

    NARCIS (Netherlands)

    Devillé, W.; Piribauer, F.; Groenewegen, P.P.

    2005-01-01

    In European countries professional opinions differ about the usefulness of periodic health examination (PHE). Austria and Germany are the only one with a standardized PHE in the basic social insurance package. New insights in the role of GPs in monitoring population health and the role of PHE in

  7. PERIODIC-SOLUTIONS IN SPONTANEOUSLY BROKEN THEORIES

    NARCIS (Netherlands)

    BRIHAYE, Y; KUNZ, J

    A class of spontaneously broken field theories is proposed, and the occurrence of their periodic, classical solutions is investigated in detail. The emergence of multiple solutions is observed, their normal modes of oscillation are studied, and the bifurcations of the classical energy functional are

  8. Periodic diffeomorphisms on homotopy E(4) surfaces

    Indian Academy of Sciences (India)

    In [9], there is an open problem proposed by Allan Edmonds: Question 1.1. Do K3 surfaces admit a periodic diffeomorphism of prime order acting trivially on cohomology (or homology)?. This question was motivated by the corresponding rigidity for holomorphic actions [1]. It was shown to be true for topological ones [4] and ...

  9. Thromboembolic Events in the Perioperative Period

    NARCIS (Netherlands)

    F. van Lier (Felix)

    2011-01-01

    textabstractThe first chapter provides an overview of cardiovascular risk identification and modification in the perioperative period. In this chapter the identification of patients at risk using various risk models and biomarkers is described. Noninvasive and invasive preoperative (stress) testing

  10. Theory of periodic conjugate heat transfer

    CERN Document Server

    Zudin, Yuri B

    2016-01-01

    This book presents the theory of periodic conjugate heat transfer in detail. It offers a simplified description of the interaction between a solid body and a fluid as a boundary value problem of the heat conduction equation for the solid body.

  11. Physics of primordial star formation

    Science.gov (United States)

    Yoshida, Naoki

    2012-09-01

    The study of primordial star formation has a history of nearly sixty years. It is generally thought that primordial stars are one of the key elements in a broad range of topics in astronomy and cosmology, from Galactic chemical evolution to the formation of super-massive blackholes. We review recent progress in the theory of primordial star formation. The standard theory of cosmic structure formation posits that the present-day rich structure of the Universe developed through gravitational amplification of tiny matter density fluctuations left over from the Big Bang. It has become possible to study primordial star formation rigorously within the framework of the standard cosmological model. We first lay out the key physical processes in a primordial gas. Then, we introduce recent developments in computer simulations. Finally, we discuss prospects for future observations of the first generation of stars.

  12. A dedicated study of new particle formation and fate in the coastal environment (PARFORCE): overview of objectives and achievements

    NARCIS (Netherlands)

    O'Dowd, C.D.; Haemeri, K.; Maekelae, J.M.; Pirjola, L.; Kulmala, M.; Jennings, S.G.; Berresheim, H.; Hansson, H-C.; Leeuw, G. de; Kunz, G.J.; Allen, A.G.; Hewitt, C.N.; Jackson, A.; Viisanen, Y.; Hoffman, T.

    2002-01-01

    A dedicated study into the formation of new particles, New Particle Formation and Fate in the Coastal Environment (PARFORCE), was conducted over a period from 1998 to 1999 at the Mace Head Atmospheric Research Station on the western coast of Ireland. Continuous measurements of new particle formation

  13. Periodic Solutions and S-Asymptotically Periodic Solutions to Fractional Evolution Equations

    Directory of Open Access Journals (Sweden)

    Jia Mu

    2017-01-01

    Full Text Available This paper deals with the existence and uniqueness of periodic solutions, S-asymptotically periodic solutions, and other types of bounded solutions for some fractional evolution equations with the Weyl-Liouville fractional derivative defined for periodic functions. Applying Fourier transform we give reasonable definitions of mild solutions. Then we accurately estimate the spectral radius of resolvent operator and obtain some existence and uniqueness results.

  14. A new method for calculating the average period of current assets turnover in the analyzed period

    Directory of Open Access Journals (Sweden)

    Kulakova Julija Nikolaevna

    2015-05-01

    Full Text Available The aim of this study is to develop a new method for calculating the average period of current assets turnover during the analyzed period without using of financial results (revenue, cost, etc.. To prove the advantages of the proposed method in comparison with the traditional method of calculating turnover the example of estimating the mean residence time in the analyzed period of working capital in the form of receivables is developed.

  15. Paleogeography of the mid-Cretaceous period

    Energy Technology Data Exchange (ETDEWEB)

    Zharkov, M.A.; Murdmaa, I.O.; Filatova, N.I. [Russian Academy of Sciences, Moscow (Russian Federation)

    1995-05-01

    Global lithologic-paleogeographic maps for the Aptian, Albian, Cenomanian, and Turonian stages of the Cretaceous were compiled for the first time using common methods and taking into consideration the paleogeographic environment of continents and oceans. Particular features of the global distribution of arid and humid environments on continents were analyzed to distinguish belts and zones of evaporite and red-bed sedimentation, coal accumulation, and bauxite and kaolin formation. It is shown that climatic zonality and the location of arid and humid environments on continents were dependent on the arrangement of continents and oceans on the surface of the Earth.

  16. Os debates pelo fim do tráfico no periódico O Philantropo (1849-1852 e a formação do povo: doenças, raça e escravidão The debate on the end of the slave trade in the periodical O Philantropo (1849-1852 and the formation of the people: illnesses, race and slavery

    Directory of Open Access Journals (Sweden)

    Kaori Kodama

    2008-01-01

    Full Text Available O propósito deste artigo é investigar a atuação do jornal O Philantropo (1849-1852, bem como da "Sociedade contra o Tráfico de Africanos e Promotora da Colonisação e da Civilização dos Indígenas", que sustentou o jornal. Procura-se atentar para a especificidade dos segmentos presentes na Sociedade em relação ao projeto de fim do tráfico, no momento em que ocorriam os debates no Parlamento. No jornal, a bandeira antitráfico combinava em suas propostas a defesa da mão-de-obra livre e um nacionalismo que muitas vezes lançava mão de argumentos racialistas. Interessa-nos, assim, destacar aspectos do debate da Sociedade através de um exame do perfil de seus sócios e na articulação que apresentaram entre as questões da colonização e da formação do povo, através dos temas da raça, das doenças e da escravidão.This paper aims at investigating the newspaper O Philantropo (1849-1852 and the Society against the Slave Trade and for the Colonization and Civilization of the Indians which supported it. It focuses on the specific roles of the Society's members in the movement for ending the slave trade, when the discussion for its suppression was taking place in Parliament. In the newspaper, ranged under the banner of the defense against the slave trade, could also be found the support for a free labor force and a nationalism which frequently made use of racialist arguments. It attempts to detach some aspects of the debate of the Society by examining the profile of its members as well as by articulating the problem of colonization with the formation of the nation through the issues of race, diseases and slavery.

  17. Equivariant surgery theories and their periodicity properties

    CERN Document Server

    Dovermann, Karl Heinz

    1990-01-01

    The theory of surgery on manifolds has been generalized to categories of manifolds with group actions in several different ways. This book discusses some basic properties that such theories have in common. Special emphasis is placed on analogs of the fourfold periodicity theorems in ordinary surgery and the roles of standard general position hypotheses on the strata of manifolds with group actions. The contents of the book presuppose some familiarity with the basic ideas of surgery theory and transformation groups, but no previous knowledge of equivariant surgery is assumed. The book is designed to serve either as an introduction to equivariant surgery theory for advanced graduate students and researchers in related areas, or as an account of the authors' previously unpublished work on periodicity for specialists in surgery theory or transformation groups.

  18. Periodic table for Floquet topological insulators

    Science.gov (United States)

    Roy, Rahul; Harper, Fenner

    2017-10-01

    Dynamical phases with novel topological properties are known to arise in driven systems of free fermions. In this paper, we obtain a `periodic table' to describe the phases of such time-dependent systems, generalizing the periodic table for static topological insulators. Using K theory, we systematically classify Floquet topological insulators from the ten Altland-Zirnbauer symmetry classes across all dimensions. We find that the static classification scheme described by a group G becomes G×n in the time-dependent case, where n is the number of physically important gaps in the quasienergy spectrum (including any gaps at quasienergy π ). The factors of G may be interpreted as arising from the bipartite decomposition of the unitary time-evolution operator. Topologically protected edge modes may arise at the boundary between two Floquet systems, and we provide a mapping between the number of such edge modes and the topological invariant of the bulk.

  19. Nonlinearities in Periodic Structures and Metamaterials

    CERN Document Server

    Denz, Cornelia; Kivshar, Yuri S

    2010-01-01

    Optical information processing of the future is associated with a new generation of compact nanoscale optical devices operating entirely with light. Moreover, adaptive features such as self-guiding, reconfiguration and switching become more and more important. Nonlinear devices offer an enormous potential for these applications. Consequently, innovative concepts for all-optical communication and information technologies based on nonlinear effects in photonic-crystal physics and nanoscale devices as metamaterials are of high interest. This book focuses on nonlinear optical phenomena in periodic media, such as photonic crystals, optically-induced, adaptive lattices, atomic lattices or metamaterials. The main purpose is to describe and overview new physical phenomena that result from the interplay between nonlinearities and structural periodicities and is a guide to actual and future developments for the expert reader in optical information processing, as well as in the physics of cold atoms in optical lattices.

  20. Periodic systems of N-atom molecules

    Science.gov (United States)

    Hefferlin, R. A.; Zhuvikin, G. V.; Caviness, K. E.; Duerksen, P. J.

    1984-10-01

    The atoms have long been classified into a periodic system, which is now based on quantum mechanics and group theory. A classification of molecules containing any number (N) of atoms is proposed. It is an extension of the periodic system of the atoms. The approach in this paper is that of group theory, although the proposed system has been subjected to exhaustive comparison with experimental and ab initio computational results for diatomic molecules, and conforms to the commonly known behaviors of molecules with larger N. Orthonormal transformations are performed so that the molecules can be arranged according to their numbers of electrons and to the differences of atomic numbers of the constituent atoms. These arrangements parallel the physical reality of atomic bonding and permit partial three-dimensional models of the systems to be constructed for molecules with as many as four atoms.

  1. MOV reliability evaluation and periodic verification scheduling

    Energy Technology Data Exchange (ETDEWEB)

    Bunte, B.D.

    1996-12-01

    The purpose of this paper is to establish a periodic verification testing schedule based on the expected long term reliability of gate or globe motor operated valves (MOVs). The methodology in this position paper determines the nominal (best estimate) design margin for any MOV based on the best available information pertaining to the MOVs design requirements, design parameters, existing hardware design, and present setup. The uncertainty in this margin is then determined using statistical means. By comparing the nominal margin to the uncertainty, the reliability of the MOV is estimated. The methodology is appropriate for evaluating the reliability of MOVs in the GL 89-10 program. It may be used following periodic testing to evaluate and trend MOV performance and reliability. It may also be used to evaluate the impact of proposed modifications and maintenance activities such as packing adjustments. In addition, it may be used to assess the impact of new information of a generic nature which impacts safety related MOVs.

  2. Periodically distributed objects with quasicrystalline diffraction pattern

    Energy Technology Data Exchange (ETDEWEB)

    Wolny, Janusz, E-mail: wolny@fis.agh.edu.pl; Strzalka, Radoslaw [Faculty of Physics and Applied Computer Science, AGH University of Science and Technology, al. Mickiewicza 30, 30-059 Krakow (Poland); Kuczera, Pawel [Faculty of Physics and Applied Computer Science, AGH University of Science and Technology, al. Mickiewicza 30, 30-059 Krakow (Poland); Laboratory of Crystallography, ETH Zurich, Wolfgang-Pauli-Strasse 10, CH-8093 Zurich (Switzerland)

    2015-03-30

    It is possible to construct fully periodically distributed objects with a diffraction pattern identical to the one obtained for quasicrystals. These objects are probability distributions of distances obtained in the statistical approach to aperiodic structures distributed periodically. The diffraction patterns have been derived by using a two-mode Fourier transform—a very powerful method not used in classical crystallography. It is shown that if scaling is present in the structure, this two-mode Fourier transform can be reduced to a regular Fourier transform with appropriately rescaled scattering vectors and added phases. Detailed case studies for model sets 1D Fibonacci chain and 2D Penrose tiling are discussed. Finally, it is shown that crystalline, quasicrystalline, and approximant structures can be treated in the same way.

  3. The super period matrix with Ramond punctures

    Science.gov (United States)

    Witten, Edward

    2015-06-01

    We generalize the super period matrix of a super Riemann surface to the case that Ramond punctures are present. For a super Riemann surface of genus g with 2 r Ramond punctures, we define, modulo certain choices that generalize those in the classical theory (and assuming a certain generic condition is satisfied), a g | r × g | r period matrix that is symmetric in the Z2-graded sense. As an application, we analyze the genus 2 vacuum amplitude in string theory compactifications to four dimensions that are supersymmetric at tree level. We find an explanation for a result that has been found in orbifold examples in explicit computations by D'Hoker and Phong: with their integration procedure, the genus 2 vacuum amplitude always vanishes "pointwise" after summing over spin structures, and hence is given entirely by a boundary contribution.

  4. RR Lyrae period luminosity relations with Spitzer

    Science.gov (United States)

    Neeley, Jillian R.; Marengo, Massimo; CRRP Team

    2017-01-01

    RR Lyrae variable stars have long been known to be valuable distance indicators, but only recently has a well defined period luminosity relationship been utilized at infrared wavelengths. In my thesis, I am combining Spitzer Space Telescope data of RR Lyrae stars obtained as part of the Carnegie RR Lyrae Program with ground based NIR data to characterize the period-luminosity-metallicity (PLZ) relation and provide an independent Population II calibration of the cosmic distance scale. I will discuss the ongoing efforts to calibrate this relation using objects such as M4 and NGC 6441 and how the first data release from the Gaia mission impacts our findings. I will also compare my preliminary empirical relations to theoretical PLZ relations derived from stellar pulsation models.

  5. [The critical period in natural fertility].

    Science.gov (United States)

    Vital Reyes, V S; Cortés-Gallegos, V

    1992-11-01

    In order to learn the natural expectancy period of first pregnancy as well as the influences of some biosocial variables, a clinical-retrospective study was performed within 1120 gravida I women. All of them attended the major institutes of health care in Mexico City (IMSS, ISSSTE, SS and DDF). Data were obtained by means of predetermined questions from subjects after the first postpartum hours. None of them had previously used any contraceptive method. Results showed age at the first pregnancy: 21.6 +/- 3.8 (years); gestational interval 22.1 +/- 19.9 (months) and a 67% achievement rate the following twelve months of sexual activity. Eutocia was seen in 54% of these population and significant linear correlation was attained between age of the patient and the gestational interval. It seems that this is the first information regarding the fertility critical period within our society.

  6. Field Optimization for short Period Undulators

    CERN Document Server

    Peiffer, P; Rossmanith, R; Schoerling, D

    2011-01-01

    Undulators dedicated to low energy electron beams, like Laser Wakefield Accelerators, require very short period lengths to achieve X-ray emission. However, at these short period length (LambdaU ~ 5 mm) it becomes difficult to reach magnetic field amplitudes that lead to a K parameter of >1, which is generally desired. Room temperature permanent magnets and even superconductive undulators using Nb-Ti as conductor material have proven insufficient to achieve the desired field amplitudes. The superconductor Nb3Sn has the theoretical potential to achieve the desired fields. However, up to now it is limited by several technological challenges to much lower field values than theoretically predicted. An alternative idea for higher fields is to manufacture the poles of the undulator body from Holmium instead of iron or to use Nb-Ti wires with a higher superconductor/copper ratio. The advantages and challenges of the different options are compared in this contribution.

  7. Fractional observer to estimate periodical forces.

    Science.gov (United States)

    Coronel-Escamilla, A; Gómez-Aguilar, J F; Torres, L; Escobar-Jimnez, R F; Olivares-Peregrino, V H

    2017-11-14

    In the present work we propose a fractional state observer with constant gain to estimate the periodical force exerted on a mechanical system by measuring only its displacement. The state observer is designed from both the Fourier series that approximates the periodical force and the equations of the damped harmonic oscillator that represents the behavior of the system. Specifically, the reconstruction of the force is carried out from the estimates of the series coefficients, which in fact are part of the dynamical system that composes the observer. Adams-Bashforth-Moulton method is used to compute the fractional derivatives of the observer in the Liouville-Caputo sense. Experiments based on real data are presented to show the advantages of using a fractional observer in the reconstruction of forces. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

  8. VITAMIN AND MINERAL CORRECTION IN PUBERTAL PERIOD

    Directory of Open Access Journals (Sweden)

    S.V. Talashova

    2009-01-01

    Full Text Available This article describes a role of calcium, phosphorus, vitamins D, A and group of vitamins B in growth and development of adolescents. Balances composition of complex medication «Kalcinova» allow preventing of deficient state in children in prepubertal period.Key words: adolescents, calcium, vitamins, nutrition.(Voprosy sovremennoi pediatrii — Current Pediatrics. 2009;8(3:120-122

  9. Periodic complex map germs and foliations.

    Science.gov (United States)

    Câmara, Leonardo M; Scárdua, Bruno A

    2017-01-01

    In this paper we study topological and analytical conditions on the orbits of a germ of diffeomorphism in the complex plane in order to obtain periodicity. In particular, we give a simple proof of a finiteness criteria for groups of analytic diffeomorphisms, stated in Brochero Martínez 2003. As an application, we derive some consequences about the integrability of complex vector fields in dimension three in a neighborhood of a singular point.

  10. Body image in different periods of adolescence

    OpenAIRE

    Valter Paulo N. Miranda; Maria Aparecida Conti; Pedro Henrique B. de Carvalho; Ronaldo Rocha Bastos; Ferreira,Maria Elisa C.

    2014-01-01

    Objective: To analyze body image in different periods of adolescence. Methods: This cross-sectional study enrolled students aged ten to 19 years old of public schools in small districts of Minas Gerais, Southeast Brazil. The Body Shape Questionnaire (BSQ), the Body Dissatisfaction Assessment Scale for Teenagers and the Silhouette Scale for Teenagers (SST) were used. Adolescence phases were classified according to the subjects' ages. Weight and height were measured in order to calculate t...

  11. Periodic pattern detection in sparse boolean sequences

    Directory of Open Access Journals (Sweden)

    Hérisson Joan

    2010-09-01

    Full Text Available Abstract Background The specific position of functionally related genes along the DNA has been shown to reflect the interplay between chromosome structure and genetic regulation. By investigating the statistical properties of the distances separating such genes, several studies have highlighted various periodic trends. In many cases, however, groups built up from co-functional or co-regulated genes are small and contain wrong information (data contamination so that the statistics is poorly exploitable. In addition, gene positions are not expected to satisfy a perfectly ordered pattern along the DNA. Within this scope, we present an algorithm that aims to highlight periodic patterns in sparse boolean sequences, i.e. sequences of the type 010011011010... where the ratio of the number of 1's (denoting here the transcription start of a gene to 0's is small. Results The algorithm is particularly robust with respect to strong signal distortions such as the addition of 1's at arbitrary positions (contaminated data, the deletion of existing 1's in the sequence (missing data and the presence of disorder in the position of the 1's (noise. This robustness property stems from an appropriate exploitation of the remarkable alignment properties of periodic points in solenoidal coordinates. Conclusions The efficiency of the algorithm is demonstrated in situations where standard Fourier-based spectral methods are poorly adapted. We also show how the proposed framework allows to identify the 1's that participate in the periodic trends, i.e. how the framework allows to allocate a positional score to genes, in the same spirit of the sequence score. The software is available for public use at http://www.issb.genopole.fr/MEGA/Softwares/iSSB_SolenoidalApplication.zip.

  12. The extraordinary spectral properties of radially periodic ...

    Indian Academy of Sciences (India)

    R. Narasimhan (Krishtel eMaging) 1461 1996 Oct 15 13:05:22

    Abstract. Since it became clear that the band structure of the spectrum of periodic. Sturm–Liouville operators t = − (d2/dr2) + q(r) does not survive a spherically sym- metric extension to Schrödinger operators T = − +V with V (x) = q(|x|) for x ∈ Rd. , d ∈ N\\ {1}, a wealth of detailed information about the spectrum of such ...

  13. Cyclic Period in the CBE Model

    CERN Document Server

    Frampton, Paul H

    2016-01-01

    In a cyclic entropy model in which the extroverse is jettisoned at turnaround with a Come Back Empty (CBE) assumption, we address matching of the contaction scale factor $\\hat{a}(t)=f(t_T){a}(t)$ to the expansion scale factor $a(t)$, where $f(t_T)$ is the ratio at turnaround of the introverse to extroverse radii. Such matching is necessary for infinite cyclicity and fixes the CBE period at $\\sim 2.6Ty$.

  14. Theoretical chemistry periodicities in chemistry and biology

    CERN Document Server

    Eyring, Henry

    1978-01-01

    Theoretical Chemistry: Periodicities in Chemistry and Biology, Volume 4 covers the aspects of theoretical chemistry. The book discusses the stably rotating patterns of reaction and diffusion; the chemistry of inorganic systems exhibiting nonmonotonic behavior; and population cycles. The text also describes the mathematical modeling of excitable media in neurobiology and chemistry; oscillating enzyme reactions; and oscillatory properties and excitability of the heart cell membrane. Selected topics from the theory of physico-chemical instabilities are also encompassed. Chemists, mechanical engin

  15. Periods of High Intensity Solar Proton Flux

    Science.gov (United States)

    Xapsos, Michael A.; Stauffer, Craig A.; Jordan, Thomas M.; Adams, James H.; Dietrich, William F.

    2012-01-01

    Analysis is presented for times during a space mission that specified solar proton flux levels are exceeded. This includes both total time and continuous time periods during missions. Results for the solar maximum and solar minimum phases of the solar cycle are presented and compared for a broad range of proton energies and shielding levels. This type of approach is more amenable to reliability analysis for spacecraft systems and instrumentation than standard statistical models.

  16. The Cerebellum, Sensitive Periods, and Autism

    Science.gov (United States)

    Wang, Samuel S.-H.; Kloth, Alexander D.; Badura, Aleksandra

    2014-01-01

    Cerebellar research has focused principally on adult motor function. However, the cerebellum also maintains abundant connections with nonmotor brain regions throughout postnatal life. Here we review evidence that the cerebellum may guide the maturation of remote nonmotor neural circuitry and influence cognitive development, with a focus on its relationship with autism. Specific cerebellar zones influence neocortical substrates for social interaction, and we propose that sensitive-period disruption of such internal brain communication can account for autism's key features. PMID:25102558

  17. Web life: The Periodic Table of Videos

    Science.gov (United States)

    2009-01-01

    Eagle-eyed readers may spot a change in this column. Previously known as Blog life, it highlighted top picks from the physics blogosphere, and was itself an outgrowth of an earlier column on physics books, Shelf life. The new Web life column will continue to feature the best of physics blogging, but it will also include other types of Web content of interest to Physics World readers. First up is a periodic table of videos from Nottingham University in the UK.

  18. Clock Genes Control Cortical Critical Period Timing

    OpenAIRE

    Kobayashi, Yohei; Ye, Zhanlei; Hensch, Takao K.

    2015-01-01

    Circadian rhythms control a variety of physiological processes, but whether they may also time brain development remains largely unknown. Here, we show that circadian clock genes control the onset of critical period plasticity in the neocortex. Within visual cortex of Clock-deficient mice, the emergence of circadian gene expression was dampened, and the maturation of inhibitory parvalbumin (PV)-cell networks slowed. Loss of visual acuity in response to brief monocular deprivation was concomit...

  19. Critical period of memory enhancement during taste avoidance conditioning in Lymnaea stagnalis.

    Directory of Open Access Journals (Sweden)

    Tomoyo Takahashi

    Full Text Available The present study investigated the optimal training procedure leading to long-lasting taste avoidance behavior in Lymnaea. A training procedure comprising 5 repeated pairings of a conditional stimulus (CS, sucrose, with an unconditional stimulus (US, a tactile stimulation to the animal's head, over a 4-day period resulted in an enhanced memory formation than 10 CS-US repeated pairings over a 2-day period or 20 CS-US repeated pairings on a single day. Backward conditioning (US-CS pairings did not result in conditioning. Thus, this taste avoidance conditioning was CS-US pairing specific. Food avoidance behavior was not observed following training, however, if snails were immediately subjected to a cold-block (4°C for 10 min. It was critical that the cold-block be applied within 10 min to block long-term memory (LTM formation. Further, exposure to the cold-block 180 min after training also blocked both STM and LTM formation. The effects of the cold-block on subsequent learning and memory formation were also examined. We found no long lasting effects of the cold-block on subsequent memory formation. If protein kinase C was activated before the conditioning paradigm, snails could still acquire STM despite exposure to the cold-block.

  20. Free-format RPG IV

    CERN Document Server

    Martin, Jim

    2013-01-01

    This how-to guide offers a concise and thorough introduction to the increased productivity, better readability, and easier program maintenance that comes with the free-format style of programming in RPG IV. Although free-format information is available in IBM manuals, it is not separated from everything else, thereby requiring hours of tedious research to track down the information needed. This book provides everything one needs to know to write RPG IV in the free-format style, and author Jim Martin not only teaches rules and syntax but also explains how this new style of coding has the pot