WorldWideScience

Sample records for puzzle comparative bac-mapping

  1. The European sea bass Dicentrarchus labrax genome puzzle: comparative BAC-mapping and low coverage shotgun sequencing

    Directory of Open Access Journals (Sweden)

    Volckaert Filip AM

    2010-01-01

    Full Text Available Abstract Background Food supply from the ocean is constrained by the shortage of domesticated and selected fish. Development of genomic models of economically important fishes should assist with the removal of this bottleneck. European sea bass Dicentrarchus labrax L. (Moronidae, Perciformes, Teleostei is one of the most important fishes in European marine aquaculture; growing genomic resources put it on its way to serve as an economic model. Results End sequencing of a sea bass genomic BAC-library enabled the comparative mapping of the sea bass genome using the three-spined stickleback Gasterosteus aculeatus genome as a reference. BAC-end sequences (102,690 were aligned to the stickleback genome. The number of mappable BACs was improved using a two-fold coverage WGS dataset of sea bass resulting in a comparative BAC-map covering 87% of stickleback chromosomes with 588 BAC-contigs. The minimum size of 83 contigs covering 50% of the reference was 1.2 Mbp; the largest BAC-contig comprised 8.86 Mbp. More than 22,000 BAC-clones aligned with both ends to the reference genome. Intra-chromosomal rearrangements between sea bass and stickleback were identified. Size distributions of mapped BACs were used to calculate that the genome of sea bass may be only 1.3 fold larger than the 460 Mbp stickleback genome. Conclusions The BAC map is used for sequencing single BACs or BAC-pools covering defined genomic entities by second generation sequencing technologies. Together with the WGS dataset it initiates a sea bass genome sequencing project. This will allow the quantification of polymorphisms through resequencing, which is important for selecting highly performing domesticated fish.

  2. A Comparative BAC map for the gilthead sea bream (Sparus aurata L.).

    Science.gov (United States)

    Kuhl, Heiner; Sarropoulou, Elena; Tine, Mbaye; Kotoulas, Georgios; Magoulas, Antonios; Reinhardt, Richard

    2011-01-01

    This study presents the first comparative BAC map of the gilthead sea bream (Sparus aurata), a highly valuated marine aquaculture fish species in the Mediterranean. High-throughput end sequencing of a BAC library yielded 92,468 reads (60.6  Mbp). Comparative mapping was achieved by anchoring BAC end sequences to the three-spined stickleback (Gasterosteus aculeatus) genome. BACs that were consistently ordered along the stickleback chromosomes accounted for 14,265 clones. A fraction of 5,249 BACs constituted a minimal tiling path that covers 73.5% of the stickleback chromosomes and 70.2% of the genes that have been annotated. The N50 size of 1,485 "BACtigs" consisting of redundant BACs is 337,253 bp. The largest BACtig covers 2.15 Mbp in the stickleback genome. According to the insert size distribution of mapped BACs the sea bream genome is 1.71-fold larger than the stickleback genome. These results represent a valuable tool to researchers in the field and may support future projects to elucidate the whole sea bream genome.

  3. A Comparative BAC Map for the Gilthead Sea Bream (Sparus aurata L.

    Directory of Open Access Journals (Sweden)

    Heiner Kuhl

    2011-01-01

    Full Text Available This study presents the first comparative BAC map of the gilthead sea bream (Sparus aurata, a highly valuated marine aquaculture fish species in the Mediterranean. High-throughput end sequencing of a BAC library yielded 92,468 reads (60.6 Mbp. Comparative mapping was achieved by anchoring BAC end sequences to the three-spined stickleback (Gasterosteus aculeatus genome. BACs that were consistently ordered along the stickleback chromosomes accounted for 14,265 clones. A fraction of 5,249 BACs constituted a minimal tiling path that covers 73.5% of the stickleback chromosomes and 70.2% of the genes that have been annotated. The N50 size of 1,485 “BACtigs” consisting of redundant BACs is 337,253 bp. The largest BACtig covers 2.15 Mbp in the stickleback genome. According to the insert size distribution of mapped BACs the sea bream genome is 1.71-fold larger than the stickleback genome. These results represent a valuable tool to researchers in the field and may support future projects to elucidate the whole sea bream genome.

  4. Puzzling Mechanisms

    Science.gov (United States)

    van Deventer, M. Oskar

    2009-01-01

    The basis of a good mechanical puzzle is often a puzzling mechanism. This article will introduce some new puzzling mechanisms, like two knots that engage like gears, a chain whose links can be interchanged, and flat gears that do not come apart. It illustrates how puzzling mechanisms can be transformed into real mechanical puzzles, e.g., by…

  5. Fiendishly puzzling

    Science.gov (United States)

    2016-12-01

    The UK's Government Communications Headquarters (GCHQ) has, over the last few years, published puzzles that keen members of the public could solve to get noticed by the organization's recruitment team. The GCHQ Puzzle Book is a chunky compendium whose readers are introduced to the whole back catalogue.

  6. Phthalate Puzzle

    Indian Academy of Sciences (India)

    Abhijit Ghosh

    2017-07-01

    The most common plasticizer, phthalates, are facing stricterregulations due to their omnipresence and possible effects onhuman health, and environment. But high cost, lack of applicationrange, and unknown long-term effects of non-phthalatealternatives make the scenario puzzling.

  7. New, puzzling insights from comparative myological studies on the old and unsolved forelimb/hindlimb enigma.

    Science.gov (United States)

    Diogo, Rui; Linde-Medina, Marta; Abdala, Virginia; Ashley-Ross, Miriam A

    2013-02-01

    Most textbooks and research reports state that the structures of the tetrapod forelimbs and hindlimbs are serial homologues. From this view, the main challenge of evolutionary biologists is not to explain the similarity between tetrapod limbs, but instead to explain why and how they have diverged. However, these statements seem to be related to a confusion between the serial homology of the vertebrate pelvic and pectoral appendages as a whole, and the serial homology of the specific soft- and hard-tissue structures of the tetrapod forelimbs and hindlimbs, leading to an even more crucial and puzzling question being overlooked: why are the skeletal and particularly the muscle structures of the forelimb and hindlimb actually so strikingly similar to each other? Herein we provide an updated discussion of these questions and test two main hypotheses: (i) that the similarity of the limb muscles is due to serial homology; and (ii) that tetrapods that use hindlimbs for a largely exclusive function (e.g. bipedalism in humans) exhibit fewer cases of similarity between forelimbs and hindlimbs than do quadrupedal species. Our review shows that of the 23 arm, forearm and hand muscles/muscle groups of salamanders, 18 (78%) have clear 'topological equivalents' in the hindlimb; in lizards, 14/24 (58%); in rats, 14/35 (40%); and in modern humans, 19/37 (51%). These numbers seem to support the idea that there is a plesiomorphic similarity and subsequent evolutionary divergence, but this tendency actually only applies to the three former quadrupedal taxa. Moreover, if one takes into account the total number of 'correspondences', one comes to a surprising and puzzling conclusion: in modern humans the number of forelimb muscles/muscle groups with clear 'equivalents' in the hindlimb (19) is substantially higher than in quadrupedal mammals such as rats (14), lizards (14) and even salamanders (18). These data contradict the hypothesis that divergent functions lead to divergent

  8. Puzzle-based versus traditional lecture: comparing the effects of pedagogy on academic performance in an undergraduate human anatomy and physiology II lab.

    Science.gov (United States)

    Stetzik, Lucas; Deeter, Anthony; Parker, Jamie; Yukech, Christine

    2015-06-23

    A traditional lecture-based pedagogy conveys information and content while lacking sufficient development of critical thinking skills and problem solving. A puzzle-based pedagogy creates a broader contextual framework, and fosters critical thinking as well as logical reasoning skills that can then be used to improve a student's performance on content specific assessments. This paper describes a pedagogical comparison of traditional lecture-based teaching and puzzle-based teaching in a Human Anatomy and Physiology II Lab. Using a single subject/cross-over design half of the students from seven sections of the course were taught using one type of pedagogy for the first half of the semester, and then taught with a different pedagogy for the second half of the semester. The other half of the students were taught the same material but with the order of the pedagogies reversed. Students' performance on quizzes and exams specific to the course, and in-class assignments specific to this study were assessed for: learning outcomes (the ability to form the correct conclusion or recall specific information), and authentic academic performance as described by (Am J Educ 104:280-312, 1996). Our findings suggest a significant improvement in students' performance on standard course specific assessments using a puzzle-based pedagogy versus a traditional lecture-based teaching style. Quiz and test scores for students improved by 2.1 and 0.4% respectively in the puzzle-based pedagogy, versus the traditional lecture-based teaching. Additionally, the assessments of authentic academic performance may only effectively measure a broader conceptual understanding in a limited set of contexts, and not in the context of a Human Anatomy and Physiology II Lab. In conclusion, a puzzle-based pedagogy, when compared to traditional lecture-based teaching, can effectively enhance the performance of students on standard course specific assessments, even when the assessments only test a limited

  9. Techniques for Solving Sudoku Puzzles

    CERN Document Server

    Chi, Eric C

    2012-01-01

    Solving Sudoku puzzles is one of the most popular pastimes in the world. Puzzles range in difficulty from easy to very challenging; the hardest puzzles tend to have the most empty cells. The current paper compares the performance of three computer algorithms in solving puzzles. Backtracking, simulated annealing, and alternating projections are generic methods for attacking combinatorial optimization problems. Our results favor backtracking. It infallibly solves Sudoku puzzles or deduces that a unique solution does not exist. However, backtracking does not scale well in high-dimensional combinatorial optimization. Hence, it is useful to expose statistics students to the other two solution techniques in a concrete setting. Simulated annealing shares a common structure with MCMC (Markov chain Monte Carlo) and enjoys wide applicability. The method of alternating projections solves the feasibility problem in convex programming. Converting a discrete optimization problem into a continuous optimization problem opens...

  10. The Proton Radius Puzzle

    Directory of Open Access Journals (Sweden)

    Downie E. J.

    2016-01-01

    Full Text Available The proton radius puzzle is the difference between the proton radius as measured with electron scattering and in the excitation spectrum of atomic hydrogen, and that measured with muonic hydrogen spectroscopy. Since the inception of the proton radius puzzle in 2010 by the measurement of Pohl et al.[1], many possible resolutions to the puzzle have been postulated, but, to date, none has been generally accepted. New data are therefore necessary to resolve the issue. We briefly review the puzzle, the proposed solutions, and the new electron scattering and spectroscopy experiments planned and underway. We then introduce the MUSE experiment, which seeks to resolve the puzzle by simultaneously measuring elastic electron and muon scattering on the proton, in both charge states, thereby providing new information to the puzzle. MUSE addresses issues of two-photon effects, lepton universality and, possibly, new physics, while providing simultaneous form factor, and therefore radius, measurements with both muons and electrons.

  11. Solving jigsaw puzzles using image features

    DEFF Research Database (Denmark)

    Nielsen, Ture R.; Drewsen, Peter; Hansen, Klaus

    2008-01-01

    algorithm which exploits the divide and conquer paradigm to reduce the combinatorially complex problem by classifying the puzzle pieces and comparing pieces drawn from the same group. The paper includes a brief preliminary investigation of some image features used in the classification.......In this article, we describe a method for automatic solving of the jigsaw puzzle problem based on using image features instead of the shape of the pieces. The image features are used for obtaining an accurate measure for edge similarity to be used in a new edge matching algorithm. The algorithm...... is used in a general puzzle solving method which is based on a greedy algorithm previously proved successful. We have been able to solve computer generated puzzles of 320 pieces as well as a real puzzle of 54 pieces by exclusively using image information. Additionally, we investigate a new scalable...

  12. Tangrams: Puzzles of Art

    Science.gov (United States)

    Fee, Brenda

    2009-01-01

    Challenging one's brain is the beginning of making great art. Tangrams are a great way to keep students thinking about their latest art project long after leaving the classroom. A tangram is a Chinese puzzle. The earliest known reference to tangrams appears in a Chinese book dated 1813, but the puzzles existed long before that date. The puzzle…

  13. A puzzle for philosophers

    Directory of Open Access Journals (Sweden)

    Nicolás Lo Guercio

    2013-12-01

    Full Text Available In the paper I tackle a puzzle by Goldberg (2009 that challenges all of us as philosophers. There are three plausible thesis, separately defensible, that together seem to lead to a contradiction: 1 Reliability is a necessary condition for epistemic justification. 2 On contested matters in philosophy, philosophers are not reliable. 3 At least some philosophical theses regarding contested matters in philosophy are epistemically justified. In this paper I will assess the status of the puzzle and attempt to solve it. In the first section, I'll present the puzzle with a little more detail. Secondly, I'll provide some general arguments to show that the alleged puzzle is not a legitimate one. Finally, in section 3, I will argue that even assuming that the puzzle can be coherently formulated, Goldberg's arguments in favor of premise (2 are either unsound or too limited in their scope in order to represent a significant or interesting problem for philosophers.

  14. PSQP: Puzzle Solving by Quadratic Programming.

    Science.gov (United States)

    Andalo, Fernanda A; Taubin, Gabriel; Goldenstein, Siome

    2017-02-01

    In this article we present the first effective method based on global optimization for the reconstruction of image puzzles comprising rectangle pieces-Puzzle Solving by Quadratic Programming (PSQP). The proposed novel mathematical formulation reduces the problem to the maximization of a constrained quadratic function, which is solved via a gradient ascent approach. The proposed method is deterministic and can deal with arbitrary identical rectangular pieces. We provide experimental results showing its effectiveness when compared to state-of-the-art approaches. Although the method was developed to solve image puzzles, we also show how to apply it to the reconstruction of simulated strip-shredded documents, broadening its applicability.

  15. The PPP Puzzle

    DEFF Research Database (Denmark)

    Juselius, Katarina

    The persistent movements away from long-run benchmark values in real exchange rates, dubbed the PPP puzzle, observed in many real exchange rates during periods of currency float have been subject to much empirical research without resolving the puzzle. The paper demonstrates how the cointegrated...... VAR approach by grouping together components of similar persistence can be used to uncover structures in the data that ultimately may help to explain theoretically the forces underlying such puzzling movements. The charaterization of the data into components which are empirically I(0), I(1), and I(2...

  16. Comparing milled fiber, Quebec ore, and textile factory dust: has another piece of the asbestos puzzle fallen into place?

    Science.gov (United States)

    Berman, D Wayne

    2010-01-01

    Results of a meta-analysis indicate that the variation in potency factors observed across published epidemiology studies can be substantially reconciled (especially for mesothelioma) by considering the effects of fiber size and mineral type, but that better characterization of historical exposures is needed before improved exposure metrics potentially capable of fully reconciling the disparate potency factors can be evaluated. Therefore, an approach for better characterizing historical exposures, the Modified Elutriator Method (MEM), was evaluated to determine the degree that dusts elutriated using this method adequately mimic dusts generated by processing in a factory. To evaluate this approach, elutriated dusts from Grade 3 milled fiber (the predominant feedstock used at a South Carolina [SC] textile factory) were compared to factory dust collected at the same facility. Elutriated dusts from chrysotile ore were also compared to dusts collected in Quebec mines and mills. Results indicate that despite the substantial variation within each sample set, elutriated dusts from Grade 3 fiber compare favorably to textile dusts and elutriated ore dusts compare to dusts from mines and mills. Given this performance, the MEM was also applied to address the disparity in lung cancer mortality per unit of exposure observed, respectively, among chrysotile miners/millers in Quebec and SC textile workers. Thus, dusts generated by elutriation of stockpiled chrysotile ore (representing mine exposures) and Grade 3 milled fiber (representing textile exposures) were compared. Results indicate that dusts from each sample differ from one another. Despite such variation, however, the dusts are distinct and fibers in Grade 3 dusts are significantly longer than fibers in ore dusts. Moreover, phase-contrast microscopy (PCM) structures in Grade 3 dusts are 100% asbestos and counts of PCM-sized structures are identical, whether viewed by PCM or transmission electron microscope (TEM). In

  17. Blood Type Puzzle.

    Science.gov (United States)

    Kelly, Janet

    1997-01-01

    Presents a blood type puzzle that provides a visual, hands-on mechanism by which students can examine blood group reactions. Offers students an opportunity to construct their own knowledge about blood types. (JRH)

  18. The puzzle of intrafamilial child sexual abuse: a meta-analysis comparing intrafamilial and extrafamilial offenders with child victims.

    Science.gov (United States)

    Seto, Michael C; Babchishin, Kelly M; Pullman, Lesleigh E; McPhail, Ian V

    2015-07-01

    Intrafamilial child sexual abuse is a serious social and health problem, yet explanations of sexual offending against children that emphasize antisocial tendencies and atypical sexual interests do not adequately explain intrafamilial offending. In this meta-analysis, we tested other explanations of intrafamilial child sexual abuse by examining 78 independent samples that compared a total of 6605 intrafamilial offenders to a total of 10,573 extrafamilial offenders, in studies disseminated between 1978 and 2013 (Mdn=2000). Intrafamilial offenders were significantly lower on variables reflecting antisocial tendencies (e.g., criminal history, juvenile delinquency, impulsivity, substance use, and psychopathy) and atypical sexual interests (e.g., pedophilia, other paraphilias, and excessive sexual preoccupation). Contrary to other explanations that have been proposed, intrafamilial offenders scored lower on offense-supportive attitudes and beliefs, emotional congruence with children, and interpersonal deficits; intrafamilial offenders also did not differ from extrafamilial offenders on most indicators of psychopathology. Intrafamilial offenders were, however, more likely to have experienced sexual abuse, family abuse or neglect, and poor parent-child attachments. There were too few studies to examine family dynamics - spousal relationship quality, parent-child victim relationship, and family functioning more generally - even though these factors have been frequently mentioned in the clinical and theoretical literatures. Implications for theories of intrafamilial sexual offending, treatment, and future directions for research are discussed.

  19. Games, puzzles, and computation

    CERN Document Server

    Hearn, Robert A

    2009-01-01

    The authors show that there are underlying mathematical reasons for why games and puzzles are challenging (and perhaps why they are so much fun). They also show that games and puzzles can serve as powerful models of computation-quite different from the usual models of automata and circuits-offering a new way of thinking about computation. The appendices provide a substantial survey of all known results in the field of game complexity, serving as a reference guide for readers interested in the computational complexity of particular games, or interested in open problems about such complexities.

  20. Boggle Logic Puzzles: Minimal Solutions

    Science.gov (United States)

    Needleman, Jonathan

    2013-01-01

    Boggle logic puzzles are based on the popular word game Boggle played backwards. Given a list of words, the problem is to recreate the board. We explore these puzzles on a 3 x 3 board and find the minimum number of three-letter words needed to create a puzzle with a unique solution. We conclude with a series of open questions.

  1. Musical Traditions. Puzzle Corner.

    Science.gov (United States)

    Andrews, Ian A.

    1999-01-01

    Discusses the changes in musical experiences, such as live versus recorded music, as society has developed technologically. Presents a crossword puzzle that focuses on the traditions and musicians of baroque, classical, and romantic music each originating in Europe. Includes the clues and word list. (CMK)

  2. The Radicalization Puzzle [video

    OpenAIRE

    Mohammed Hafez; Center for Homeland Defense and Security Naval Postgraduate School

    2015-01-01

    This 20 minute lecture, by Dr. Mohammad Hafez of the Naval Postgraduate School examines the driving factors behind the process of radicalization, turning seemingly ordinary men and women into potential terrorists. The lecture is based on the article "The Radicalization Puzzle: A Theoretical Synthesis of Empirical Approaches to Homegrown Extremism" in Studies in Conflict and Terrorism, by Mohammad Hafez and Creighton Mullins.

  3. Puzzles in physics

    Indian Academy of Sciences (India)

    Hsiang-Nan Li

    2006-11-01

    I discuss some puzzles observed in exclusive -meson decays, concentrating on the large difference between the direct CP asymmetries in the 0 → ∓± and ± → 0± modes, the large 0 → 00 branching ratio, and the large deviation of the mixing-induced CP asymmetries in the $b → sq\\bar{q}$ penguins from those in the $b → c\\bar{c}s$ trees.

  4. Wooden Geometric Puzzles: Design and Hardness Proofs

    NARCIS (Netherlands)

    Alt, H.; Bodlaender, H.L.; Kreveld, M.J. van; Rote, G.; Tel, G.

    2007-01-01

    We discuss some new geometric puzzles and the complexity of their extension to arbitrary sizes. For gate puzzles and two-layer puzzles we prove NP-completeness of solving them. Not only the solution of puzzles leads to interesting questions, but also puzzle design gives rise to interesting

  5. Wooden Geometric Puzzles: Design and Hardness Proofs

    NARCIS (Netherlands)

    Alt, H.; Bodlaender, H.L.; Kreveld, M.J. van; Rote, G.; Tel, G.

    2008-01-01

    We discuss some new geometric puzzles and the complexity of their extension to arbitrary sizes. For gate puzzles and two-layer puzzles we prove NP-completeness of solving them. Not only the solution of puzzles leads to interesting questions, but also puzzle design gives rise to interesting

  6. Wooden Geometric Puzzles: Design and Hardness Proofs

    NARCIS (Netherlands)

    Alt, H.; Bodlaender, H.L.; Kreveld, M.J. van; Rote, G.; Tel, G.

    2007-01-01

    We discuss some new geometric puzzles and the complexity of their extension to arbitrary sizes. For gate puzzles and two-layer puzzles we prove NP-completeness of solving them. Not only the solution of puzzles leads to interesting questions, but also puzzle design gives rise to interesting theoretic

  7. Wooden Geometric Puzzles: Design and Hardness Proofs

    NARCIS (Netherlands)

    Alt, H.; Bodlaender, H.L.; Kreveld, M.J. van; Rote, G.; Tel, G.

    2008-01-01

    We discuss some new geometric puzzles and the complexity of their extension to arbitrary sizes. For gate puzzles and two-layer puzzles we prove NP-completeness of solving them. Not only the solution of puzzles leads to interesting questions, but also puzzle design gives rise to interesting theoretic

  8. El puzzle de la pajarita

    OpenAIRE

    Flores, Pablo

    2002-01-01

    La enseñanza de las matemáticas en la escolaridad obligatoria está volviendo a valorar las cualidades educativas de la geometría sintética de formas, reconociendo el valor educativo de los recursos manipulativos como los puzzles. Son especialmente valorados los puzzles simples y versátiles. En este artículo queremos mostrar un puzzle que hemos ideado a partir de la descomposición de una figura familiar: el perfil de la pajarita de papel. El puzzle se compone sólo de tres piezas, por lo que es...

  9. The infinity puzzle

    CERN Document Server

    Close, Frank

    2011-01-01

    We are living in a Golden Age of Physics. Forty or so years ago, three brilliant, yet little-known scientists - an American, a Dutchman, and an Englishman - made breakthroughs which later inspired the construction of the Large Hadron Collider at CERN in Geneva: a 27 kilometer-long machine which has already costs ten billion dollars, taken twenty years to build, and now promises to reveal how the universe itself came to be. The Infinity Puzzle is the inside story of those forty years of research, breakthrough, and endeavour. Peter Higgs, Gerard 't Hooft and James Bjorken, were the three scienti

  10. The Entrepreneurial Earnings Puzzle

    DEFF Research Database (Denmark)

    Chen, Jing; Åstebro, Thomas

    2014-01-01

    underreporting by entrepreneurs. Using a nationwide panel survey representing U.S. households over 15 years, we estimate that entrepreneurs on average earn 4% less per year than employees. However, after correcting for income underreporting, the mean financial gain to entrepreneurship is positive and large......A review of recent evidence on relative earnings from entrepreneurship versus wage work presents a puzzle: why do individuals become entrepreneurs when entrepreneurs on average apparently earn less than employees? After considering several potential explanations, we empirically analyze one: income...

  11. Idiosyncratic Volatility Puzzle

    DEFF Research Database (Denmark)

    Aslanidis, Nektarios; Christiansen, Charlotte; Lambertides, Neophytos;

    from a large pool of macroeconomic and Önancial variables. Cleaning for macro-Önance e§ects reverses the puzzling negative relation between returns and idiosyncratic volatility documented previously. Portfolio analysis shows that the e§ects from macro-Önance factors are economically strong......In this paper, we scrutinize the cross-sectional relation between idiosyncratic volatility and stock returns. As a novelty, the idiosyncratic volatility is obtained by conditioning upon macro-Önance factors as well as upon traditional asset pricing factors. The macro-Önance factors are constructed...

  12. Basic Functional Analysis Puzzles of Spectral Flow

    DEFF Research Database (Denmark)

    Booss-Bavnbek, Bernhelm

    2011-01-01

    We explain an array of basic functional analysis puzzles on the way to general spectral flow formulae and indicate a direction of future topological research for dealing with these puzzles.......We explain an array of basic functional analysis puzzles on the way to general spectral flow formulae and indicate a direction of future topological research for dealing with these puzzles....

  13. Sleep for Kids: Games and Puzzles

    Science.gov (United States)

    Games and Puzzles These games and puzzles can help you learn more about sleep! Learn about sleep with this fun crossword puzzle! Test your memory ... can't sleep? • dreams • • bring out the stars • games and puzzles • pj bear booklet • • home • about us • ...

  14. The Puzzling Ophiuchus Stream

    Science.gov (United States)

    Kohler, Susanna

    2016-01-01

    Dwarf galaxies or globular clusters orbiting the Milky Way can be pulled apart by tidal forces, leaving behind a trail of stars known as a stellar stream. One such trail, the Ophiuchus stream, has posed a serious dynamical puzzle since its discovery. But a recent study has identified four stars that might help resolve this streams mystery.Conflicting TimescalesThe stellar stream Ophiuchus was discovered around our galaxy in 2014. Based on its length, which appears to be 1.6 kpc, we can calculate the time that has passed since its progenitor was disrupted and the stream was created: ~250 Myr. But the stars within it are ~12 Gyr old, and the stream orbits the galaxy with a period of ~350 Myr.Given these numbers, we can assume that Ophiuchuss progenitor completed many orbits of the Milky Way in its lifetime. So why would it only have been disrupted 250 million years ago?Fanning StreamLed by Branimir Sesar (Max Planck Institute for Astronomy), a team of scientists has proposed an idea that might help solve this puzzle. If the Ophiuchus stellar stream is on a chaotic orbit common in triaxial potentials, which the Milky Ways may be then the stream ends can fan out, with stars spreading in position and velocity.The fanned part of the stream, however, would be difficult to detect because of its low surface brightness. As a result, the Ophiuchus stellar stream could actually be longer than originally measured, implying that it was disrupted longer ago than was believed.Search for Fan StarsTo test this idea, Sesar and collaborators performed a search around the ends of the stream, looking for stars thatare of the right type to match the stream,are at the predicted distance of the stream,are located near the stream ends, andhave velocities that match the stream and dont match the background halo stars.Histogram of the heliocentric velocities of the 43 target stars. Six stars have velocities matching the stream velocity. Two of these are located in the main stream; the other

  15. [The Parkinson puzzle].

    Science.gov (United States)

    Guseo, András

    2012-12-30

    Parkinson's disease is one of the most frequent progressive degenerative disorders with unknown origin of the nervous system. The commutation of the disease on Guam led to the discovery of a neurotoxin which was also found in other continents. This neurotoxin was identified in the common cyanobacteria (blue-green algae). Early clinical observations suggested some loose correlations with gastric and duodenal ulcer and Parkinson's disease, while recent studies revealed a toxin, almost identical to that found in cyanobacteria in one strain of Helicobacter pylori, which proved to cause Parkinson like symptoms in animals. Therefore, it cannot be ruled out that there is a slowly progressive poisoning in Parkinson's disease. The disease specific alpha-sinuclein inclusions can be found in nerve cells of the intestinal mucosa far before the appearance of clinical symptoms indicating that the disease may start in the intestines. These results are strengthened by the results of Borody's fecal transplants, after which in Parkinson patients showed a symptomatic improvement. Based on these observations the Parkinson puzzle is getting complete. Although these observations are not evidence based, they may indicate a new way for basic clinical research, as well as a new way of thinking for clinicians. These new observations in psycho-neuro-immunology strengthen the fact that immunological factors may also play a critical factor facilitating local cell necrosis which may be influenced easily.

  16. Puzzled by GRB 060218

    CERN Document Server

    Ghisellini, G; Tavecchio, F

    2006-01-01

    We study the optical-UV/X-ray spectral energy distribution of GRB 060218 during the prompt phase and during what seems to be the afterglow phase. The results are puzzling, since if the opt-UV and the X-ray emission belong to a single black body, then its luminosity is too large, and it cannot be interpreted as the signature of the supernova shock breakout. Problems are also encountered in associating the expected supernova shock breakout emission with either the opt-UV or the X-ray emission. In the former case we derive too small ejecta velocities; in the latter case, on the contrary, the required velocity is too large. We then present what we think is the most conservative alternative explanation, namely a synchrotron spectrum, self-absorbed in the opt-UV and extending up to the X-ray band, where we observe the emission of the most energetic electrons, which are responsible for the exponential roll-over of the spectrum. The fit to the data is quite satisfactory, and can explain the entire spectrum except the...

  17. Imaginary Cubes and Their Puzzles

    Directory of Open Access Journals (Sweden)

    Hideki Tsuiki

    2012-05-01

    Full Text Available Imaginary cubes are three dimensional objects which have square silhouette projections in three orthogonal ways just as a cube has. In this paper, we study imaginary cubes and present assembly puzzles based on them. We show that there are 16 equivalence classes of minimal convex imaginary cubes, among whose representatives are a hexagonal bipyramid imaginary cube and a triangular antiprism imaginary cube. Our main puzzle is to put three of the former and six of the latter pieces into a cube-box with an edge length of twice the size of the original cube. Solutions of this puzzle are based on remarkable properties of these two imaginary cubes, in particular, the possibility of tiling 3D Euclidean space.

  18. Multichanneled puzzle-like encryption

    Science.gov (United States)

    Amaya, Dafne; Tebaldi, Myrian; Torroba, Roberto; Bolognini, Néstor

    2008-07-01

    In order to increase data security transmission we propose a multichanneled puzzle-like encryption method. The basic principle relies on the input information decomposition, in the same way as the pieces of a puzzle. Each decomposed part of the input object is encrypted separately in a 4 f double random phase mask architecture, by setting the optical parameters in a determined status. Each parameter set defines a channel. In order to retrieve the whole information it is necessary to properly decrypt and compose all channels. Computer simulations that confirm our proposal are presented.

  19. Famous puzzles of great mathematicians

    CERN Document Server

    Petković, Miodrag S

    2009-01-01

    This entertaining book presents a collection of 180 famous mathematical puzzles and intriguing elementary problems that great mathematicians have posed, discussed, and/or solved. The selected problems do not require advanced mathematics, making this book accessible to a variety of readers. Mathematical recreations offer a rich playground for both amateur and professional mathematicians. Believing that creative stimuli and aesthetic considerations are closely related, great mathematicians from ancient times to the present have always taken an interest in puzzles and diversions. The goal of this

  20. Chemistry of Art and Color Sudoku Puzzles

    Science.gov (United States)

    Welsh, Michael J.

    2007-01-01

    Sudoku puzzle format was used to teach light science and chemistry terms to students of Chemistry of Art and Color. The puzzles were used to motivate and encourage students to learn chemistry in an easier and in friendly fashion.

  1. À chacun son puzzle

    Directory of Open Access Journals (Sweden)

    Jean-Noël Ferrié

    2012-05-01

    Full Text Available Le texte soutient que le « tournant naturaliste » que l’on nous invite à négocier ne donne aucun moyen supplémentaire pour parvenir à une description perspicace de ce que les gens font dans des circonstances précises, l’existence humaine pouvant être considérée comme une collection de circonstances précises. Sans doute le naturalisme nous permet-il de comprendre comment certaines actions humaines sont possibles, mais cela ne nous dit pas pourquoi et comment elles font sens pour tout un chacun. La méthodologie nécessaire pour éclaircir le premier point obscurcit généralement le second. Le mieux est donc de considérer que les deux approches ne vont pas de pair. Ce point de vue est soutenu à partir d’exemple tirés de l’anthropologie de la religion.To each one his puzzle. For a serene methodological pluralismThe text argues that the « naturalistic turn » that we are invited to negotiate does not give any additional means to achieve an insightful description of what people do in specific circumstances, and human existence can be considered as a collection of specific circumstances. Probably naturalism allows us to understand how some human actions are possible, but that does not tell us why and how they make sense for everyone. The methodology needed to clarify the first point usually obscures the second one. The best way is to consider that the two approaches do not go together. The text supports this view from an example drawn from the anthropology of religion.A cada uno su rompecabezas. En favor de un pluralismo metodológico serenoEl texto argumenta que la inflexión naturalista a la que se nos invita a participar no proporciona ningún medio suplementario que desemboque en una descripción perspicaz de lo que la gente hace en circunstancias concretas ya que la existencia humana puede ser considerada como una concatenación de circunstancias concretas. Sin duda el naturalismo nos permite comprender como son

  2. Practical Client Puzzle from Repeated Squaring

    NARCIS (Netherlands)

    Jeckmans, A.

    2009-01-01

    Cryptographic puzzles have been proposed by Merkle [15] to relay secret information between parties over an insecure channel. Client puzzles, a type of cryptographic puzzle, have been proposed by Juels and Brainard [8] to defend a server against denial of service attacks. However there is no general

  3. Teaching Inductive Reasoning with Puzzles

    Science.gov (United States)

    Wanko, Jeffrey J.

    2017-01-01

    Working with language-independent logic structures can help students develop both inductive and deductive reasoning skills. The Japanese publisher Nikoli (with resources available both in print and online) produces a treasure trove of language-independent logic puzzles. The Nikoli print resources are mostly in Japanese, creating the extra…

  4. A 72-year-old Danish puzzle resolved--comparative analysis of phenotypes in families with different-sized HOXD13 polyalanine expansions

    DEFF Research Database (Denmark)

    Kjær, Klaus Wilbrandt; Hansen, Lars; Eiberg, Hans;

    2005-01-01

    A phenotype-genotype correlation was previously described for carriers of different sized of polyalanine expansions in HOXD13. We report on a detailed comparison of 55 members (approximately 220 limbs) from 4 Danish families with duplications of 21 or 27 bp, expanding the polyalanine repeat from 15......-5. The length of metacarpals and phalangeal bones in rays 1, 2, and 5 was measured on hand radiographs and converted to Z-scores. The relative difference between corresponding right and left bones and directional, total, and fluctuating asymmetry was calculated for each individual. All of these parameters were...... compared between carriers of the +9 alanine expansion, the +7 alanine expansion, and non-mutation carriers with affected parents from the two families. Upper limb scores and the rate of abnormal bones (>2SD) were significantly higher in the first group than in the others. The first metacarpal...

  5. MODELING AND SOLVING SELF-REFERENTIAL PUZZLES

    Directory of Open Access Journals (Sweden)

    Maja Bubalo

    2012-07-01

    Full Text Available The so-called self-referential puzzles are a very interesting kind of logic puzzles,aiming at developing the skill of logical thinking. A self-referential puzzle consists of asequence of questions about the puzzle itself. In this paper, we shall show some selfreferentialpuzzles, demonstrate how to model and solve them as propositional logicproblems, and how to mechanically generate new puzzles. For this, we shall make use ofthe specific advantages of Mozart/Oz system – the finite domain constraint programminglanguage and environment.We shall also show some new puzzles, according to our best knowledge not yet publishedelsewhere. The program in Mozart/Oz using our method generated these puzzles.

  6. Finding Solutions to Sudoku Puzzles Using Human Intuitive Heuristics

    Directory of Open Access Journals (Sweden)

    Nelishia Pillay

    2012-09-01

    Full Text Available Sudoku is a logical puzzle that has achieved international popularity. Given this, there have been a number of computer solvers developed for this puzzle. Various methods including genetic algorithms, simulated annealing, particle swarm optimization and harmony search have been evaluated for this purpose. The approach described in this paper combines human intuition and optimization to solve Sudoku problems. The main contribution of this paper is a set of heuristic moves, incorporating human expertise, to solve Sudoku puzzles. The paper investigates the use of genetic programming to optimize a space of programs composed of these heuristics moves, with the aim of evolving a program that can produce a solution to the Sudoku problem instance. Each program is a combination of randomly selected moves. The approach was tested on 1800 Sudoku puzzles of differing difficulty. The approach presented was able to solve all 1800 problems, with a majority of these problems being solved in under a second. For a majority of the puzzles evolution was not needed and random combinations of the moves created during the initial population produced solutions. For the more difficult problems at least one generation of evolution was needed to find a solution. Further analysis revealed that solution programs for the more difficult problems could be found by enumerating random combinations of the move operators, however at a cost of higher runtimes. The performance of the approach presented was found to be comparable to other methods used to solve Sudoku problems and in a number of cases produced better results.

  7. RBC Models and the Hours-Wages Puzzle: Puzzle Solved!

    OpenAIRE

    Vasilev, Aleksandar

    2015-01-01

    This paper shows that a modified real business cycle (RBC) model, one that includes home production and fiscal spending shocks, can solve one of the RBC puzzles and generates zero correlation between wages and hours. In addition, the micro-founded model presented here provides a sound theoretical model to analyze fiscal policy in a neoclassical framework and is able to capture many aspects of the data that the benchmark RBC model was missing.

  8. Neutron Star News and Puzzles

    CERN Document Server

    Prakash, Madappa

    2014-01-01

    Gerry Brown has had the most influence on my career in Physics, and my life after graduate studies. In this article, I give a brief account of some of the many ways in which Gerry shaped my research. Recent and on-going research on neutron stars in which the group built from scratch by Gerry at Stony Brook has made significant strides are reviewed. Selected puzzles about neutron stars that remain to be solved are noted.

  9. Neutron star news and puzzles

    Science.gov (United States)

    Prakash, Madappa

    2014-08-01

    Gerry Brown has had the most influence on my career in Physics, and my life after graduate studies. This article gives a brief account of some of the many ways in which Gerry shaped my research. Focus is placed on the significant strides on neutron star research made by the group at Stony Brook, which Gerry built from scratch. Selected puzzles about neutron stars that remain to be solved are noted.

  10. Construction-Paper Puzzle Masterpieces

    Science.gov (United States)

    Vance, Shelly

    2010-01-01

    Creating an appreciation of art history in her junior-high students has always been one of the author's greatest challenges as an art teacher. In this article, the author describes how her eighth-grade students re-created a famous work of art--piece by piece, like a puzzle or a stained-glass window--out of construction paper. (Contains 1 resource.)

  11. How to Solve the Torus Puzzle

    Directory of Open Access Journals (Sweden)

    Masahiro Nakamura

    2012-01-01

    Full Text Available In this paper, we consider the following sliding puzzle called torus puzzle. In an m by n board, there are mn pieces numbered from 1 to mn. Initially, the pieces are placed in ascending order. Then they are scrambled by rotating the rows and columns without the player’s knowledge. The objective of the torus puzzle is to rearrange the pieces in ascending order by rotating the rows and columns. We provide a solution to this puzzle. In addition, we provide lower and upper bounds on the number of steps for solving the puzzle. Moreover, we consider a variant of the torus puzzle in which each piece is colored either black or white, and we present a hardness result for solving it.

  12. The Magnets Puzzle is NP-Complete

    DEFF Research Database (Denmark)

    Kölker, Jonas

    2012-01-01

    In a Magnets puzzle, one must pack magnets in a box subjet to polarity and numeric constraints. We show that solvability of Magnets instances is NP-complete.......In a Magnets puzzle, one must pack magnets in a box subjet to polarity and numeric constraints. We show that solvability of Magnets instances is NP-complete....

  13. Project-A-Puzzle. Second Edition.

    Science.gov (United States)

    Porter, Richard D.

    This set of transparency masters of mathematical puzzles has as its intent the development of logical and perceptual skills. The puzzles include patterns, magic squares, and counting problems. Solutions and follow-up suggestions are provided on the back of each page. (MP)

  14. Automated Word Puzzle Generation via Topic Dictionaries

    CERN Document Server

    Pinter, Balazs; Szabo, Zoltan; Lorincz, Andras

    2012-01-01

    We propose a general method for automated word puzzle generation. Contrary to previous approaches in this novel field, the presented method does not rely on highly structured datasets obtained with serious human annotation effort: it only needs an unstructured and unannotated corpus (i.e., document collection) as input. The method builds upon two additional pillars: (i) a topic model, which induces a topic dictionary from the input corpus (examples include e.g., latent semantic analysis, group-structured dictionaries or latent Dirichlet allocation), and (ii) a semantic similarity measure of word pairs. Our method can (i) generate automatically a large number of proper word puzzles of different types, including the odd one out, choose the related word and separate the topics puzzle. (ii) It can easily create domain-specific puzzles by replacing the corpus component. (iii) It is also capable of automatically generating puzzles with parameterizable levels of difficulty suitable for, e.g., beginners or intermedia...

  15. Puzzle based teaching versus traditional instruction in electrocardiogram interpretation for medical students – a pilot study

    Directory of Open Access Journals (Sweden)

    Dhoble Abhijeet

    2009-01-01

    Full Text Available Abstract Background Most medical professionals are expected to possess basic electrocardiogram (EKG interpretation skills. But, published data suggests that residents' and physicians' EKG interpretation skills are suboptimal. Learning styles differ among medical students; individualization of teaching methods has been shown to be viable and may result in improved learning. Puzzles have been shown to facilitate learning in a relaxed environment. The objective of this study was to assess efficacy of teaching puzzle in EKG interpretation skills among medical students. Methods This is a reader blinded crossover trial. Third year medical students from College of Human Medicine, Michigan State University participated in this study. Two groups (n = 9 received two traditional EKG interpretation skills lectures followed by a standardized exam and two extra sessions with the teaching puzzle and a different exam. Two other groups (n = 6 received identical courses and exams with the puzzle session first followed by the traditional teaching. EKG interpretation scores on final test were used as main outcome measure. Results The average score after only traditional teaching was 4.07 ± 2.08 while after only the puzzle session was 4.04 ± 2.36 (p = 0.97. The average improvement after the traditional session was followed up with a puzzle session was 2.53 ± 1.94 while the average improvement after the puzzle session was followed with the traditional session was 2.08 ± 1.73 (p = 0.67. The final EKG exam score for this cohort (n = 15 was 84.1 compared to 86.6 (p = 0.22 for a comparable sample of medical students (n = 15 at a different campus. Conclusion Teaching EKG interpretation with puzzles is comparable to traditional teaching and may be particularly useful for certain subgroups of students. Puzzle session are more interactive and relaxing, and warrant further investigations on larger scale.

  16. Impossible folding puzzles and other mathematical paradoxes

    CERN Document Server

    Sarcone, Gianni A

    2014-01-01

    Do all problems have solutions? Is complexity synonymous with difficulty? This original collection of mathematical puzzles and paradoxes proves that things aren't always what they seem! Readers will discover that nothing is as easy or as difficult as it looks and that puzzles can have one, several, or no solutions.The fun-filled puzzles begin with The Tricky Hole, a challenge that involves pushing a large coin through a small hole in a sheet of paper without ripping or making any cuts in the paper. Advance to the Elastic Playing Card, in which it's possible to cut a hole into a playing card bi

  17. The Complexity of the Puzzles of Final Fantasy XIII-2

    CERN Document Server

    Johnston, Nathaniel

    2012-01-01

    We analyze the computational complexity of solving the three "temporal rift" puzzles in the recent popular video game Final Fantasy XIII-2. We show that the Tile Trial puzzle is NP-hard and we provide an efficient algorithm for solving the Crystal Bonds puzzle. We also show that slight generalizations of the Crystal Bonds and Hands of Time puzzles are NP-hard.

  18. Effect of a puzzle on the process of students' learning about cardiac physiology.

    Science.gov (United States)

    Cardozo, Lais Tono; Miranda, Aline Soares; Moura, Maria José Costa Sampaio; Marcondes, Fernanda Klein

    2016-09-01

    The aim of the present study was to evaluate the effects of using a puzzle to learn about cardiac physiology. Students were divided into control and game groups. In class 1, the control group had a 2-h theoretical class about cardiac physiology, including a detailed description of the phases of the cardiac cycle, whereas the game group had a 50-min theoretical class without the description of the cardiac cycle. In class 2, the control group did an assessment exercise before an activity with the cardiac puzzle and the game group answered questions after the above-mentioned activity. While solving the puzzle, the students had to describe the cardiac cycle by relating the concepts of heart morphology and physiology. To evaluate short-term learning, the number of wrong answers and grades in the assessment exercise were compared between the control and game groups. To evaluate medium-term learning, we compared the grades obtained by students of the control and game groups in questions about cardiac physiology that formed part of the academic exam. In the assessment exercise, the game group presented a lower number of errors and higher score compared with the control group. In the academic exam, applied after both groups had used the puzzle, there was no difference in the scores obtained by the control and game groups in questions about cardiac physiology. These results showed a positive effect of the puzzle on students' learning about cardiac physiology compared with those not using the puzzle.

  19. Systematic Risk and the Muni Puzzle

    National Research Council Canada - National Science Library

    John M.R. Chalmers

    2006-01-01

    The muni puzzle refers to the empirical fact that relative to taxable bond yields, long-term tax-exempt yields are significantly higher than predicted by theory, while short-term yields conform well to theory...

  20. CP violation: Another piece of the puzzle

    Science.gov (United States)

    Durieux, Gauthier; Grossman, Yuval

    2017-04-01

    A study of Λb baryon decays has provided the first direct experimental evidence that spinning matter and antimatter differ. This result may help us understand the puzzling matter-antimatter imbalance in the Universe.

  1. The Monotonicity Puzzle: An Experimental Investigation of Incentive Structures

    Directory of Open Access Journals (Sweden)

    Jeannette Brosig

    2010-05-01

    Full Text Available Non-monotone incentive structures, which - according to theory - are able to induce optimal behavior, are often regarded as empirically less relevant for labor relationships. We compare the performance of a theoretically optimal non-monotone contract with a monotone one under controlled laboratory conditions. Implementing some features relevant to real-world employment relationships, our paper demonstrates that, in fact, the frequency of income-maximizing decisions made by agents is higher under the monotone contract. Although this observed behavior does not change the superiority of the non-monotone contract for principals, they do not choose this contract type in a significant way. This is what we call the monotonicity puzzle. Detailed investigations of decisions provide a clue for solving the puzzle and a possible explanation for the popularity of monotone contracts.

  2. The Puzzle of Rice Domestication

    Institute of Scientific and Technical Information of China (English)

    Tao Sang; Song Ge

    2007-01-01

    The origin of cultivated rice has puzzled plant biologists for decades. This is due, at least in part, to the complex evolutionary dynamics in rice cultivars and wild progenitors, particularly rapid adaptive differentiation and continuous gene flow within and between cultivated and wild rice. The long-standing controversy over single versus multiple and annual versus perennial origins of cultivated rice has been brought into shaper focus with the rapid accumulation of genetic and phylogenetic data. Molecular phylogenetic analyses revealed ancient genomic differentiation between rice cultivars, suggesting that they were domesticated from divergent wild populations. However, the recently cloned domestication gene sh4, responsible for the reduction of grain shattering from wild to cultivated rice, seems to have originated only once. Herein, we propose two models to reconcile apparently conflicting evidence regarding rice domestication. The snow-balling model considers a single origin of cultivated rice. In this model, a core of critical domestication alleles was fixed in the founding cultivar and then acted to increase the genetic diversity of cultivars through hybridization with wild populations. The combination model considers multiple origins of cultivated rice. In this model, initial cultivars were domesticated from divergent wild populations and fixed different sets of domestication alleles. Subsequent crosses among these semi-domesticated cultivars resulted in the fixation of a similar set of critical domestication alleles in the contemporary cultivars. In both models, introgression has played an important role in rice domestication. Recent and future introgression of beneficial genes from the wild gene pool through conventional and molecular breeding programs can be viewed as the continuation of domestication.

  3. Particle Filter with State Permutations for Solving Image Jigsaw Puzzles

    Science.gov (United States)

    Yang, Xingwei; Adluru, Nagesh; Latecki, Longin Jan

    2016-01-01

    We deal with an image jigsaw puzzle problem, which is defined as reconstructing an image from a set of square and non-overlapping image patches. It is known that a general instance of this problem is NP-complete, and it is also challenging for humans, since in the considered setting the original image is not given. Recently a graphical model has been proposed to solve this and related problems. The target label probability function is then maximized using loopy belief propagation. We also formulate the problem as maximizing a label probability function and use exactly the same pairwise potentials. Our main contribution is a novel inference approach in the sampling framework of Particle Filter (PF). Usually in the PF framework it is assumed that the observations arrive sequentially, e.g., the observations are naturally ordered by their time stamps in the tracking scenario. Based on this assumption, the posterior density over the corresponding hidden states is estimated. In the jigsaw puzzle problem all observations (puzzle pieces) are given at once without any particular order. Therefore, we relax the assumption of having ordered observations and extend the PF framework to estimate the posterior density by exploring different orders of observations and selecting the most informative permutations of observations. This significantly broadens the scope of applications of the PF inference. Our experimental results demonstrate that the proposed inference framework significantly outperforms the loopy belief propagation in solving the image jigsaw puzzle problem. In particular, the extended PF inference triples the accuracy of the label assignment compared to that using loopy belief propagation.

  4. Learning structural bioinformatics and evolution with a snake puzzle

    Directory of Open Access Journals (Sweden)

    Gonzalo S. Nido

    2016-12-01

    Full Text Available We propose here a working unit for teaching basic concepts of structural bioinformatics and evolution through the example of a wooden snake puzzle, strikingly similar to toy models widely used in the literature of protein folding. In our experience, developed at a Master’s course at the Universidad Autónoma de Madrid (Spain, the concreteness of this example helps to overcome difficulties caused by the interdisciplinary nature of this field and its high level of abstraction, in particular for students coming from traditional disciplines. The puzzle will allow us discussing a simple algorithm for finding folded solutions, through which we will introduce the concept of the configuration space and the contact matrix representation. This is a central tool for comparing protein structures, for studying simple models of protein energetics, and even for a qualitative discussion of folding kinetics, through the concept of the Contact Order. It also allows a simple representation of misfolded conformations and their free energy. These concepts will motivate evolutionary questions, which we will address by simulating a structurally constrained model of protein evolution, again modelled on the snake puzzle. In this way, we can discuss the analogy between evolutionary concepts and statistical mechanics that facilitates the understanding of both concepts. The proposed examples and literature are accessible, and we provide supplementary material (see ‘Data Availability’ to reproduce the numerical experiments. We also suggest possible directions to expand the unit. We hope that this work will further stimulate the adoption of games in teaching practice.

  5. Puzzle Pedagogy: A Use of Riddles in Mathematics Education

    Science.gov (United States)

    Farnell, Elin

    2017-01-01

    In this article, I present a collection of puzzles appropriate for use in a variety of undergraduate courses, along with suggestions for relevant discussion. Logic puzzles and riddles have long been sources of amusement for mathematicians and the general public alike. I describe the use of puzzles in a classroom setting, and argue for their use as…

  6. A Resolution of the Purchasing Power Parity Puzzle

    DEFF Research Database (Denmark)

    Frydman, Roman; Goldberg, Michael D.; Johansen, Søren

    the "Purchasing Power Parity puzzle". In this paper, we trace the puzzle to exchange rate modelers' use of the "Rational Expectations Hypothesis". We show that once imperfect knowledge is recognized, a monetary model is able to account for the puzzle, as well as other salient features of the data, including...

  7. Puzzle Pedagogy: A Use of Riddles in Mathematics Education

    Science.gov (United States)

    Farnell, Elin

    2017-01-01

    In this article, I present a collection of puzzles appropriate for use in a variety of undergraduate courses, along with suggestions for relevant discussion. Logic puzzles and riddles have long been sources of amusement for mathematicians and the general public alike. I describe the use of puzzles in a classroom setting, and argue for their use as…

  8. A Resolution of the Purchasing Power Parity Puzzle

    DEFF Research Database (Denmark)

    Frydman, Roman; Goldberg, Michael D.; Johansen, Søren;

    the "Purchasing Power Parity puzzle". In this paper, we trace the puzzle to exchange rate modelers' use of the "Rational Expectations Hypothesis". We show that once imperfect knowledge is recognized, a monetary model is able to account for the puzzle, as well as other salient features of the data, including...

  9. Reinforcing Geometric Properties with Shapedoku Puzzles

    Science.gov (United States)

    Wanko, Jeffrey J.; Nickell, Jennifer V.

    2013-01-01

    Shapedoku is a new type of puzzle that combines logic and spatial reasoning with understanding of basic geometric concepts such as slope, parallelism, perpendicularity, and properties of shapes. Shapedoku can be solved by individuals and, as demonstrated here, can form the basis of a review for geometry students as they create their own. In this…

  10. The Forward Premium Puzzle only emerges gradually

    NARCIS (Netherlands)

    K. Bernoth (Kerstin); J. von Hagen; C.G. de Vries (Casper)

    2007-01-01

    textabstractThe forward premium puzzle (FPP) is the negative correlation between the forward premium and the realized exchange rate return at maturities of a month and beyond. Some recent evidence shows that at maturities of multiple years and at the highest intra day frequency the correlation is po

  11. The Forward Premium Puzzle only emerges gradually

    NARCIS (Netherlands)

    K. Bernoth (Kerstin); J. von Hagen; C.G. de Vries (Casper)

    2007-01-01

    textabstractThe forward premium puzzle (FPP) is the negative correlation between the forward premium and the realized exchange rate return at maturities of a month and beyond. Some recent evidence shows that at maturities of multiple years and at the highest intra day frequency the correlation is

  12. Exploring Organic Mechanistic Puzzles with Molecular Modeling

    Science.gov (United States)

    Horowitz, Gail; Schwartz, Gary

    2004-01-01

    The molecular modeling was used to reinforce more general skills such as deducing and drawing reaction mechanisms, analyzing reaction kinetics and thermodynamics and drawing reaction coordinate energy diagrams. This modeling was done through the design of mechanistic puzzles, involving reactions not familiar to the students.

  13. New data and an old puzzle

    DEFF Research Database (Denmark)

    Lee, S Hong; Byrne, Enda M; Hultman, Christina M

    2015-01-01

    BACKGROUND: A long-standing epidemiological puzzle is the reduced rate of rheumatoid arthritis (RA) in those with schizophrenia (SZ) and vice versa. Traditional epidemiological approaches to determine if this negative association is underpinned by genetic factors would test for reduced rates of o...

  14. Usefulness of Crossword Puzzles in Helping First-Year BVSc Students Learn Veterinary Terminology.

    Science.gov (United States)

    Abuelo, Angel; Castillo, Cristina; May, Stephen A

    2016-01-01

    Appropriate terminology is essential for successful communication among health professionals. However, students have traditionally been encouraged to learn terminology by rote memorization and recall, strategies that students try to avoid. The use of crossword puzzles as a learning tool has been evaluated in other education disciplines, but not for terminology related to veterinary science. Hence, the objective of this study was to test whether crossword puzzles might be an effective aid to learning veterinary terminology. Forty-two first-year students enrolled in a Bachelor of Veterinary Science program were randomly divided into two groups and their previous knowledge of veterinary terms tested. One group received a list of 30 terms with their definitions. The other group received the same list plus six specially designed puzzles incorporating these 30 terms. After 50 minutes, both groups completed a post-intervention test and the results were compared statistically. The results showed that the students using the crossword puzzles performed better in the post-intervention test, correctly retaining more terms than the students using only rote learning. In addition, qualitative data, gathered through an electronic survey and focus group discussions, revealed a positive attitude among students toward the use of crossword puzzles.

  15. A MULTISET APPROACH FOR RECOGNITION OF HANDWRITTEN CHARACTERS USING PUZZLE PIECES

    Directory of Open Access Journals (Sweden)

    Ashlin Deepa R.N

    2012-07-01

    Full Text Available Image pattern matching is one of the most widely used techniques in character recognition. A pattern is the description of an object. Although a large number of papers have been reported on handwritten character recognition, it is still a very challenging problem. Recognition of characters is based on pattern classification. In this paper a hybrid approach is proposed using fuzzy technique and multiset comparison to recognize handwritten characters. Fuzzy technique is used to measure the variations in the features of handwritten numerals to form strings of character. Features are selected from the preprocessed image and the feature is labeled using fuzzy logic. Strings of a character are formed from these labeled primitives. Each string is divided into a multiset of puzzle pieces by repeatedly applying a mask which is comprised of all ones. The string is padded with anchors at the beginning and end. The mask is placed over the string, beginning at a certain character, and reading off all characters corresponding to 1 bit in the mask, thus producing one puzzle piece. To divide a string into multiset of puzzle pieces, the mask is applied at all shifts in the string starting at each character. Thus for each prototype character, we associate a multiset of puzzle pieces, which form the database. The multiset of puzzle pieces of an unknown character is constructed and compared with the same in the database, leading to the identification of the unknown character.

  16. Educational Policy Research: Progress, Puzzles, and Challenges

    Directory of Open Access Journals (Sweden)

    Richard J. Murnane

    2012-10-01

    Full Text Available This article addresses three topics. The first concerns the reasons that American education, which served the United States so well for the first three-quarters of the twentieth century, is not adequate today, and is especially not successful in providing disadvantaged children with the skills they need to escape poverty. The second concerns lessons from policy analyses about the efficacy of alternative approaches to improving American education, especially the education of its most disadvantaged children. I will make the case that research provides encouraging evidence on several policy approaches. At the same time, the research reveals puzzles that I believe we need to take seriously in thinking about future research to inform the design of the next round of policies. Finally, I suggest some directions for policy research that come from taking seriously puzzles in the evidence.

  17. On the B -> pi pi puzzle

    CERN Document Server

    Li, H; Li, Hsiang-nan; Mishima, Satoshi

    2006-01-01

    We investigate the resolutions in the literature to the B -> pi pi puzzle arising from the large observed B^0 -> pi^0 pi^0 branching ratio, and conclude that the puzzle still stands. The next-to-leading-order (NLO) contributions from the vertex corrections, the quark loops, and the magnetic penguin evaluated in the perturbative QCD approach, having saturated the experimental upper bound of the B^0 -> rho^0 rho^0 branching ratio, do not help. The inclusion of the NLO jet function from the soft-collinear effective theory into the QCD-improved factorization approach, though enhancing the B^0 -> pi^0 pi^0 branching ratio sufficiently, deteriorates the predictions for the B^\\pm -> pi^0 K^\\pm and B^0 -> pi^\\mp K^\\pm direct CP asymmetries, and overshoots the bound of the B^0 -> rho^0 rho^0 branching ratio. The effect of final-state interaction through either elastic or inelastic channels has been constrained by the B -> pi K data, and is not enough to resolve the B -> pi pi puzzle.

  18. The Gran Sasso muon puzzle

    CERN Document Server

    Fernandez-Martinez, Enrique

    2012-01-01

    We carry out a time-series analysis of the combined data from three experiments measuring the cosmic muon flux at the Gran Sasso laboratory, at a depth of 3800 m.w.e. These data, taken by the MACRO, LVD and Borexino experiments, span a period of over 20 years, and correspond to muons with a threshold energy, at sea level, of around 1.3 TeV. We compare the best-fit period and phase of the full muon data set with the combined DAMA/NaI and DAMA/LIBRA data, which spans the same time period, as a test of the hypothesis that the cosmic ray muon flux is responsible for the annual modulation detected by DAMA. We find in the muon data a large-amplitude fluctuation with a period of around one year, and a phase that is incompatible with that of the DAMA modulation at 5.2 sigmas. Aside from this annual variation, the muon data also contains a further significant modulation with a period between 10 and 11 years and a power well above the 99.9% C.L threshold for noise, whose phase corresponds well with the solar cycle: a s...

  19. Early puzzle play: a predictor of preschoolers' spatial transformation skill.

    Science.gov (United States)

    Levine, Susan C; Ratliff, Kristin R; Huttenlocher, Janellen; Cannon, Joanna

    2012-03-01

    Individual differences in spatial skill emerge prior to kindergarten entry. However, little is known about the early experiences that may contribute to these differences. The current study examined the relation between children's early puzzle play and their spatial skill. Children and parents (n = 53) were observed at home for 90 min every 4 months (6 times) between 2 and 4 years of age (26 to 46 months). When children were 4 years 6 months old, they completed a spatial task involving mental transformations of 2-dimensional shapes. Children who were observed playing with puzzles performed better on this task than those who did not, controlling for parent education, income, and overall parent word types. Moreover, among those children who played with puzzles, frequency of puzzle play predicted performance on the spatial transformation task. Although the frequency of puzzle play did not differ for boys and girls, the quality of puzzle play (a composite of puzzle difficulty, parent engagement, and parent spatial language) was higher for boys than for girls. In addition, variation in puzzle play quality predicted performance on the spatial transformation task for girls but not for boys. Implications of these findings as well as future directions for research on the role of puzzle play in the development of spatial skill are discussed.

  20. A puzzle form of a non-verbal intelligence test gives significantly higher performance measures in children with severe intellectual disability

    Directory of Open Access Journals (Sweden)

    Crewther Sheila G

    2008-08-01

    Full Text Available Abstract Background Assessment of 'potential intellectual ability' of children with severe intellectual disability (ID is limited, as current tests designed for normal children do not maintain their interest. Thus a manual puzzle version of the Raven's Coloured Progressive Matrices (RCPM was devised to appeal to the attentional and sensory preferences and language limitations of children with ID. It was hypothesized that performance on the book and manual puzzle forms would not differ for typically developing children but that children with ID would perform better on the puzzle form. Methods The first study assessed the validity of this puzzle form of the RCPM for 76 typically developing children in a test-retest crossover design, with a 3 week interval between tests. A second study tested performance and completion rate for the puzzle form compared to the book form in a sample of 164 children with ID. Results In the first study, no significant difference was found between performance on the puzzle and book forms in typically developing children, irrespective of the order of completion. The second study demonstrated a significantly higher performance and completion rate for the puzzle form compared to the book form in the ID population. Conclusion Similar performance on book and puzzle forms of the RCPM by typically developing children suggests that both forms measure the same construct. These findings suggest that the puzzle form does not require greater cognitive ability but demands sensory-motor attention and limits distraction in children with severe ID. Thus, we suggest the puzzle form of the RCPM is a more reliable measure of the non-verbal mentation of children with severe ID than the book form.

  1. Manchester's Magiscope: An Interesting Optics Puzzle

    Science.gov (United States)

    Lancor, Rachael; Lancor, Brian

    2017-02-01

    The Magiscope was an attraction at Manchester's department store in Madison, WI, in 1939 that allowed children to peek into Santa's workshop (as shown in Fig. 1). The "magiscope" was a telescope-like device that gave children the illusion they were looking at a distant Santa, when in fact they were looking at a fabricated workshop on an upper level of the department store. In this article, we describe how we used the puzzle of the magiscope as a final assessment for our optics unit in an introductory physics course.

  2. Last piece of the puzzle for ATLAS

    CERN Multimedia

    Clare Ryan

    At around 15.40 on Friday 29th February the ATLAS collaboration cracked open the champagne as the second of the small wheels was lowered into the cavern. Each of ATLAS' small wheels are 9.3 metres in diameter and weigh 100 tonnes including the massive shielding elements. They are the final parts of ATLAS' muon spectrometer. The first piece of ATLAS was installed in 2003 and since then many detector elements have journeyed down the 100 metre shaft into the ATLAS underground cavern. This last piece completes this gigantic puzzle.

  3. Nature's Greatest Puzzles

    Energy Technology Data Exchange (ETDEWEB)

    Quigg, Chris; /Fermilab

    2005-02-01

    It is a pleasure to be part of the SLAC Summer Institute again, not simply because it is one of the great traditions in our field, but because this is a moment of great promise for particle physics. I look forward to exploring many opportunities with you over the course of our two weeks together. My first task in talking about Nature's Greatest Puzzles, the title of this year's Summer Institute, is to deconstruct the premise a little bit.

  4. The puzzle of TRPV4 channelopathies.

    Science.gov (United States)

    Nilius, Bernd; Voets, Thomas

    2013-02-01

    Hereditary channelopathies, that is, mutations in channel genes that alter channel function and are causal for the pathogenesis of the disease, have been described for several members of the transient receptor potential channel family. Mutations in the TRPV4 gene, encoding a polymodal Ca(2+) permeable channel, are causative for several human diseases, which affect the skeletal system and the peripheral nervous system, with highly variable phenotypes. In this review, we describe the phenotypes of TRPV4 channelopathies and overlapping symptoms. Putative mechanisms to explain the puzzle, and how mutations in the same region of the channel cause different diseases, are discussed and experimental approaches to tackle this surprising problem are suggested.

  5. The China puzzle: Opportunities for accounting research

    Institute of Scientific and Technical Information of China (English)

    Suresh; Radhakrishnan

    2014-01-01

    How can China achieve phenomenal economic growth despite what is considered as "weak" institutions in market-based economies? Xu(2011) provides a framework to understand this puzzle. Specifically, he suggests that China’s institutional framework of Regionally Decentralized Authoritarian regime was likely responsible for the phenomenal economic growth despite what is considered "weak" institutions for market-based economies. While recent accounting research provides insights into the relationship between agency issues, and accounting and control systems in the China context, accounting researchers can use the institutional feature of RDAs to provide insights into the role of accounting and control systems in non-market-based settings.

  6. Magic star puzzle for educational mathematics

    Science.gov (United States)

    Gan, Yee Siang; Fong, Wan Heng; Sarmin, Nor Haniza

    2013-04-01

    One of the interesting fields in recreational mathematics is the magic number arrangement. There are different kinds of arrays in the arrangement for a group of numbers. In particular, one of the arrays in magic number arrangement is called magic star. In fact, magic star involves combinatorics that contributes to geometrical analysis and number theory. Hence, magic star is suitable to be introduced as educational mathematics to cultivate interest in different area of mathematics. To obtain the solutions of normal magic stars of order six, the possible sets of numbers for every line in a magic star have been considered. Previously, the calculation for obtaining the solutions has been done manually which is time-consuming. Therefore, a programming code to generate all the fundamental solutions for normal magic star of order six without including the properties of rotation and reflection has been done. In this puzzle, a magic star puzzle is created by using Matlab software, which enables a user to verify the entries for the cells of magic star of order six. Moreover, it is also user-friendly as it provides interactive commands on the inputs given by the user, which enables the user to detect the incorrect inputs. In addition, user can also choose to view all the fundamental solutions as generated by the programming code.

  7. Sudoku Puzzles for First-Year Organic Chemistry Students

    Science.gov (United States)

    Perez, Alice L.; Lamoureux, G.

    2007-01-01

    Sudoku puzzle was designed to teach about amino acids and functional groups to the students of undergraduate organic chemistry students. The puzzles focus on helping the student learn the name, 3-letter code and 1-letter code of common amino acids and functional groups.

  8. WAIS-IV visual puzzles in a mixed clinical sample.

    Science.gov (United States)

    Fallows, Robert R; Hilsabeck, Robin C

    2012-01-01

    Little is known about which cognitive functions underlie the new Visual Puzzles subtest of the Wechsler Adult Intelligence Scale - Fourth Edition (WAIS-IV). The purpose of this study was to investigate relationships between Visual Puzzles and common neuropsychological measures in a mixed clinical sample. A total of 44 veterans (75% men) were administered the WAIS-IV as part of a neuropsychological evaluation. Average age was 47.4 years (SD = 11.8), and average education was 13.8 years (SD = 2.3). Correlations were conducted to examine relationships between Visual Puzzles, demographic variables, and neuropsychological measures. Hierarchical regression analysis was used to determine which measures contributed the most variance to Visual Puzzles. Visual Puzzles correlated significantly with measures of visuospatial reasoning, verbal learning and recall, mental flexibility, processing speed, and naming, which accounted for 50% of the variance in Visual Puzzles performance. The results indicate that Visual Puzzles is not a pure measure of visuoperceptual reasoning, at least in a mixed clinical sample, because memory, mental flexibility, processing speed, and language abilities also contribute to successful performance of the task. Thus it may be important to consider other aspects of cognitive functioning when interpreting Visual Puzzles performance.

  9. The Crossword Puzzle as a Teaching Examination Tool.

    Science.gov (United States)

    Borcher, Glenda; And Others

    1994-01-01

    Animal science students (n=107) answered questions in both crossword puzzle and fill-in-the-blank format; 41 students in another study received either format as weekly review/quizzes. Students answered more questions correctly with crossword puzzles and enjoyed the challenge, although they appeared more willing to attempt answers with the fill-in…

  10. Crossword Puzzles as Learning Tools in Introductory Soil Science

    Science.gov (United States)

    Barbarick, K. A.

    2010-01-01

    Students in introductory courses generally respond favorably to novel approaches to learning. To this end, I developed and used three crossword puzzles in spring and fall 2009 semesters in Introductory Soil Science Laboratory at Colorado State University. The first hypothesis was that crossword puzzles would improve introductory soil science…

  11. The Puzzle of the Scandinavian Welfare State and Social Trust

    DEFF Research Database (Denmark)

    Svendsen, Gunnar Lind Haase; Svendsen, Gert Tinggaard

    2015-01-01

    The Scandinavian welfare model is a puzzle to economists: It works economically, even though free-riding should prevail with its explosive cocktail of high taxation and high social benefits. One overlooked solution to the puzzle could be the unique stock of social trust present in Scandinavia. Here...

  12. Puzzle of the $\\Lambda_c$ spectrum

    CERN Document Server

    Lü, Qi-Fang; Liu, Xiang; Matsuki, Takayuki

    2016-01-01

    There is a puzzle in the $\\Lambda_c^+$ family, i.e., one member with $J^P=3/2^+$ is missing in a $L=2$ multiplet which the heavy quark effective theory predicts, and $J^P$'s of $\\Lambda_c(2765)^+$ and $\\Lambda_c(2940)^+$ are unknown. Using a light diquark picture to calculate baryon masses, we study possible assignments of two $\\Lambda_c$'s with unknown $J^P$ and the missing $\\Lambda_c^+$ with $3/2^+$ for $L=2$, and we find the most probable possibility that the peak corresponding to $\\Lambda_c(2880)^+$ actually includes a missing member with spin $3/2^+$ for $L=2$ and that quantum numbers of $\\Lambda_c(2765)^+$ and $\\Lambda_c(2940)^+$ are $2S(1/2^+)$ and $2P(1/2^-)$, respectively.

  13. Heavy quarkonium: progress, puzzles, and opportunities

    CERN Document Server

    Brambilla, N; Heltsley, B K; Vogt, R; Bodwin, G T; Eichten, E; Frawley, A D; Meyer, A B; Mitchell, R E; Papadimitriou, V; Petreczky, P; Petrov, A A; Robbe, P; Vairo, A; Andronic, A; Arnaldi, R; Artoisenet, P; Bali, G; Bertolin, A; Bettoni, D; Brodzicka, J; Bruno, G E; Caldwell, A; Catmore, J; Chang, C H; Chao, K T; Chudakov, E; Cortese, P; Crochet, P; Drutskoy, A; Ellwanger, U; Faccioli, P; Gabareen Mokhtar, A; Garcia i Tormo, X; Hanhart, C; Harris, F A; Kaplan, D M; Klein, S R; Kowalski, H; Lansberg, J P; Levichev, E; Lombardo, V; Lourenco, C; Maltoni, F; Mocsy, A; Mussa, R; Navarra, F S; Negrini, M; Nielsen, M; Olsen, S L; Pakhlov, P; Pakhlova, G; Peters, K; Polosa, A D; Qian, W; Qiu, J W; Rong, G; Sanchis-Lozano, M A; Scomparin, E; Senger, P; Simon, F; Stracka, S; Sumino, Y; Voloshin, M; Weiss, C; Wohri, H K; Yuan, C Z

    2011-01-01

    A golden age for heavy quarkonium physics dawned a decade ago, initiated by the confluence of exciting advances in quantum chromodynamics (QCD) and an explosion of related experimental activity. The early years of this period were chronicled in the Quarkonium Working Group (QWG) CERN Yellow Report (YR) in 2004, which presented a comprehensive review of the status of the field at that time and provided specific recommendations for further progress. However, the broad spectrum of subsequent breakthroughs, surprises, and continuing puzzles could only be partially anticipated. Since the release of the YR, the BESII program concluded only to give birth to BESIII; the $B$-factories and CLEO-c flourished; quarkonium production and polarization measurements at HERA, JLab, and the Tevatron matured; and heavy-ion collisions at RHIC have opened a window on the deconfinement regime. All these experiments leave legacies of quality, precision, and unsolved mysteries for quarkonium physics, and therefore beg for continuing ...

  14. The electron screening puzzle and nuclear clustering

    Science.gov (United States)

    Spitaleri, C.; Bertulani, C. A.; Fortunato, L.; Vitturi, A.

    2016-04-01

    Accurate measurements of nuclear reactions of astrophysical interest within, or close to, the Gamow peak show evidence of an unexpected effect attributed to the presence of atomic electrons in the target. The experiments need to include an effective "screening" potential to explain the enhancement of the cross sections at the lowest measurable energies. Despite various theoretical studies conducted over the past 20 years and numerous experimental measurements, a theory has not yet been found that can explain the cause of the exceedingly high values of the screening potential needed to explain the data. In this letter we show that instead of an atomic physics solution of the "electron screening puzzle", the reason for the large screening potential values is in fact due to clusterization effects in nuclear reactions, in particular for reaction involving light nuclei.

  15. A new piece of the puzzle

    CERN Document Server

    2005-01-01

    The team responsible for the installation of the hadronic calorimeter's central barrel after completion of the assembly work. Assembly of the great ATLAS puzzle continues underground. On 10 December, the final module of the central barrel of the tile hadronic calorimeter was assembled. This piece of the tile calorimeter had already been assembled above ground during a "dress rehearsal" in 2003 (see Bulletin no 46/2003, 10 November 2003). The hadronic calorimeter's two other barrels, the so-called "extended barrels", remain to be assembled with this first central barrel, which now surrounds the electromagnetic calorimeter barrel that was lowered into the cavern at the end of October. At the end of November, the second of the eight barrel toroid coils was also installed.

  16. Resolution to the B -> pi K puzzle

    CERN Document Server

    Li, H; Sanda, A I; Li, Hsiang-nan; Mishima, Satoshi

    2005-01-01

    We calculate the important next-to-leading-order contributions to the B -> pi K, pi pi decays from the vertex corrections, the quark loops, and the magnetic penguins in the perturbative QCD approach. It is found that the latter two reduce the leading-order penguin amplitudes by about 10%, and modify only the B -> pi K branching ratios. The main effect of the vertex corrections is to increase the small color-suppressed tree amplitude by a factor of 3, which then resolves the large difference between the direct CP asymmetries of the B^0 -> pi^\\mp K^\\pm and B^\\pm -> pi^0 K^\\pm modes. The puzzle from the large B^0 -> pi^0 pi^0 branching ratio still remains.

  17. Heavy quarkonium: progress, puzzles, and opportunities

    CERN Document Server

    Brambilla, N; Heltsley, B K; Vogt, R; Bodwin, G T; Eichten, E; Frawley, A D; Meyer, A B; Mitchell, R E; Papadimitriou, V; Petreczky, P; Petrov, A A; Robbe, P; Vairo, A; Andronic, A; Arnaldi, R; Artoisenet, P; Bali, G; Bertolin, A; Bettoni, D; Brodzicka, J; Bruno, G E; Caldwell, A; Catmore, J; Chang, C H; Chao, K T; Chudakov, E; Cortese, P; Crochet, P; Drutskoy, A; Ellwanger, U; Faccioli, P; Gabareen Mokhtar, A; Garcia i Tormo, X; Hanhart, C; Harris, F A; Kaplan, D M; Klein, S R; Kowalski, H; Lansberg, J P; Levichev, E; Lombardo, V; Lourenco, C; Maltoni, F; Mocsy, A; Mussa, R; Navarra, F S; Negrini, M; Nielsen, M; Olsen, S L; Pakhlov, P; Pakhlova, G; Peters, K; Polosa, A D; Qian, W; Qiu, J W; Rong, G; Sanchis-Lozano, M A; Scomparin, E; Senger, P; Simon, F; Stracka, S; Sumino, Y; Voloshin, M; Weiss, C; Wohri, H K; Yuan, C Z

    2011-01-01

    A golden age for heavy quarkonium physics dawned a decade ago, initiated by the confluence of exciting advances in quantum chromodynamics (QCD) and an explosion of related experimental activity. The early years of this period were chronicled in the Quarkonium Working Group (QWG) CERN Yellow Report (YR) in 2004, which presented a comprehensive review of the status of the field at that time and provided specific recommendations for further progress. However, the broad spectrum of subsequent breakthroughs, surprises, and continuing puzzles could only be partially anticipated. Since the release of the YR, the BESII program concluded only to give birth to BESIII; the $B$-factories and CLEO-c flourished; quarkonium production and polarization measurements at HERA, JLab, and the Tevatron matured; and heavy-ion collisions at RHIC have opened a window on the deconfinement regime. All these experiments leave legacies of quality, precision, and unsolved mysteries for quarkonium physics, and therefore beg for continuing ...

  18. A Common Solution of Two Cosmic Puzzles

    CERN Document Server

    Dado, Shlomo

    2014-01-01

    The origin of the diffuse extragalactic gamma-ray background, which was measured with the large area telescope (LAT) aboard the Fermi satellite at energy below 820 GeV, and of the diffuse cosmic background of neutrinos, which was observed at much higher energies with the IceCube detector deep under the south pole ice, are among the current unsolved major cosmic puzzles. Here we show that their properties indicate a common origin: the decay of mesons produced in collisions of cosmic rays accelerated in relativistic jets with matter in/near source. Moreover, their properties are those expected if their common source is the highly relativistic jets that produce the long duration gamma ray bursts in core collapse supernovae of type Ic, which take place mostly in the densest regions of giant molecular clouds in star forming galaxies.

  19. Matter-antimatter puzzle: LHCb improves resolution

    CERN Multimedia

    Antonella Del Rosso

    2012-01-01

    In 2010, Fermilab’s DØ experiment reported a one percent difference in the properties of matter and antimatter in decays of B mesons (that is, particles containing beauty quarks) to muons. Saturday, at the ICHEP Conference in Melbourne, the LHCb experiment at CERN presents new results, which do not confirm this anomaly and are consistent with the Standard Model predictions. The same experiment has also presented the first evidence of asymmetry arising in other decays of the same family of mesons. The image becomes clearer but the puzzle has not yet been solved.   Inside the LHCb detector. The matter-antimatter imbalance in the Universe is a very hot topic in physics. The conundrum arises from the fact that, although objects made of antimatter are not observed in the Universe, theory predicts that matter and antimatter be created equally in particle interactions and in the Big Bang. Only small deviations from this very symmetric behaviour are incorporated in the theory. E...

  20. Exfoliation syndrome: assembling the puzzle pieces.

    Science.gov (United States)

    Pasquale, Louis R; Borrás, Terete; Fingert, John H; Wiggs, Janey L; Ritch, Robert

    2016-09-01

    To summarize various topics and the cutting edge approaches to refine XFS pathogenesis that were discussed at the 21st annual Glaucoma Foundation Think Tank meeting in New York City, Sept. 19-20, 2014. The highlights of three categories of talks on cutting edge research in the field were summarized. Exfoliation syndrome (XFS) is a systemic disorder with a substantial ocular burden, including high rates of cataract, cataract surgery complications, glaucoma and retinal vein occlusion. New information about XFS is akin to puzzle pieces that do not quite join together to reveal a clear picture regarding how exfoliation material (XFM) forms. Meeting participants concluded that it is unclear how the mild homocysteinemia seen in XFS might contribute to the disarrayed extracellular aggregates characteristic of this syndrome. Lysyl oxidase-like 1 (LOXL1) variants are unequivocally genetic risk factors for XFS but exactly how these variants contribute to the assembly of exfoliation material (XFM) remains unclear. Variants in a new genomic region, CACNA1A associated with XFS, may alter calcium concentrations at the cell surface and facilitate XFM formation but much more work is needed before we can place this new finding in proper context. It is hoped that various animal model and ex vivo systems will emerge that will allow for proper assembly of the puzzle pieces into a coherent picture of XFS pathogenesis. A clear understanding of XFS pathogenesis may lead to 'upstream solutions' to reduce the ocular morbidity produced by XFS. © 2015 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

  1. Real exchange rate persistence and the excess return puzzle

    DEFF Research Database (Denmark)

    Juselius, Katarina; Assenmacher, Katrin

    2017-01-01

    The PPP puzzle refers to the wide swings of nominal exchange rates around their long-run equilibrium values whereas the excess return puzzle represents the persistent deviation of the domestic-foreign interest rate differential from the expected change in the nominal exchange rate. Using the I(2......) cointegrated VAR model, much of the excess return puzzle disappears when an uncertainty premium in the foreign exchange market, proxied by the persistent PPP gap, is introduced. Self-reinforcing feedback mechanisms seem to cause the persistence in the Swiss-US parity conditions. These results support imperfect...

  2. Puzzling through General Chemistry: A Light-Hearted Approach to Engaging Students with Chemistry Content

    Science.gov (United States)

    Boyd, Susan L.

    2007-01-01

    Several puzzles are designed to be used by chemistry students as learning tools and teach them basic chemical concepts. The topics of the puzzles are based on the chapters from Chemistry, The Central Science used in general chemistry course and the puzzles are in various forms like crosswords, word searches, number searches, puzzles based on…

  3. An Analysis of Closed-end Fund Puzzle for Emerging Capital Markets

    Directory of Open Access Journals (Sweden)

    Victor Dragota

    2008-10-01

    Full Text Available This paper analyzes the closed-end fund puzzle for an emerging capital market, respectively the Romanian one. Comparatively to more developed markets, as long as small markets are often very illiquid, it has to be used some specific valuation techniques in order to estimate the market values for closed-end funds. Also, one problem is this estimation can be made only in some (punctual moments.

  4. Formative Assessment Probes: Mountaintop Fossil: A Puzzling Phenomenon

    Science.gov (United States)

    Keeley, Page

    2015-01-01

    This column focuses on promoting learning through assessment. This month's issue describes using formative assessment probes to uncover several ways of thinking about the puzzling discovery of a marine fossil on top of a mountain.

  5. Sampling Random Bioinformatics Puzzles using Adaptive Probability Distributions

    DEFF Research Database (Denmark)

    Have, Christian Theil; Appel, Emil Vincent; Bork-Jensen, Jette

    2016-01-01

    We present a probabilistic logic program to generate an educational puzzle that introduces the basic principles of next generation sequencing, gene finding and the translation of genes to proteins following the central dogma in biology. In the puzzle, a secret "protein word" must be found...... by assembling DNA from fragments (reads), locating a gene in this sequence and translating the gene to a protein. Sampling using this program generates random instance of the puzzle, but it is possible constrain the difficulty and to customize the secret protein word. Because of these constraints...... and the randomness of the generation process, sampling may fail to generate a satisfactory puzzle. To avoid failure we employ a strategy using adaptive probabilities which change in response to previous steps of generative process, thus minimizing the risk of failure....

  6. Experiments towards resolving the proton charge radius puzzle

    CERN Document Server

    Antognini, A; Amaro, F D; Amaro, P; Abdou-Ahmed, M; Biraben, F; Chen, T -L; Covita, D S; Dax, A J; Diepold, M; Fernandes, L M P; Franke, B; Galtier, S; Gouvea, A L; Götzfried, J; Graf, T; Hänsch, T W; Hildebrandt, M; Indelicato, P; Julien, L; Kirch, K; Knecht, A; Kottmann, F; Krauth, J J; Liu, Y -W; Machado, J; Monteiro, C M B; Mulhauser, F; Nez, F; Santos, J P; Santos, J M F dos; Szabo, C I; Taqqu, D; Veloso, J F C A; Voss, A; Weichelt, B; Pohl, R

    2015-01-01

    We review the status of the proton charge radius puzzle. Emphasis is given to the various experiments initiated to resolve the conflict between the muonic hydrogen results and the results from scattering and regular hydrogen spectroscopy.

  7. Experiments towards resolving the proton charge radius puzzle

    Directory of Open Access Journals (Sweden)

    Antognini A.

    2016-01-01

    Full Text Available We review the status of the proton charge radius puzzle. Emphasis is given to the various experiments initiated to resolve the conflict between the muonic hydrogen results and the results from scattering and regular hydrogen spectroscopy.

  8. CROSSWORD PUZZLE INCREASE ATTENTION OF CHILDREN WITH ADHD

    Directory of Open Access Journals (Sweden)

    Ah. Yusuf

    2017-07-01

    Full Text Available Introduction: Attention deficit is one of three main problems of children with Attention Deficit Hyperactivity Disorder (ADHD. Children experience difficulty of paying attention and concentrating to one or more things or objects. As a results these children cannot perform the task well. Crossword puzzle is one of games that may increase attention and concentration. The aim of this study was to analyze the effect of crossword puzzle to increase attention of children with ADHD. Method: Pre-experimental design was employed in this study. The population was ADHD students in Cakra Autisme Therapy. Seven students were recruited by means of purposive sampling. The independent variable was crossword puzzle and the dependent variable was the increase of attention. Data were collected using observation sheet and analyzed using Wilcoxon Signed Rank Test with level of significance of α≤ 0.05. Result: Result showed that crossword puzzle could increase attention. Respondent’s attention improved from less to good attention, particularly in playing activities (p=0.014. Analysis: This finding suggests that there was differences of attention between pre and post-test. It can be concluded that crossword puzzle can increase attention of the students with ADHD. Discussion: It is recommended for teachers and parents of ADHD children to give them crossword puzzle game everyday at school or at home. Further studies should involve larger sample size and employs another game not only to increase attention, but also reduce hyperactivity and impulsivity of ADHD child.

  9. Local associations and the barium puzzle

    CERN Document Server

    Reddy, Arumalla B S

    2015-01-01

    We have observed high-dispersion echelle spectra of main-sequence stars in five nearby young associations -- Argus, Carina-Near, Hercules-Lyra, Orion and Subgroup B4 -- and derived abundances for elements ranging from Na to Eu. These are the first chemical abundance measurements for two of the five associations, while the remaining three associations are analysed more extensively in our study. Our results support the presence of chemical homogeneity among association members with a typical star-to-star abundance scatter of about 0.06 dex or less over many elements. The five associations show log$\\epsilon$(Li) consistent with their age and share a solar chemical composition for all elements with the exception of Ba. We find that all the heavy elements (Y, Zr, La, Ce, Nd, Sm and Eu) exhibit solar ratios, i.e., [X/Fe] $\\simeq$ 0, while Ba is overabundant by about 0.2-0.3 dex. The origin of the overabundance of Ba is a puzzle. Within the formulation of the s-process, it is difficult to create a higher Ba abundanc...

  10. Peripartum cardiomyopathy: A puzzle closer to solution

    Science.gov (United States)

    Fett, James D

    2014-01-01

    Peripartum cardiomyopathy (PPCM) represents new heart failure in a previously heart-healthy peripartum patient. It is necessary to rule out all other known causes of heart failure before accepting a diagnosis of PPCM. The modern era for PPCM in the United States and beyond began with the report of the National Institutes of Health PPCM Workshop in 2000, clarifying all then-currently known aspects of the disease. Since then, hundreds of publications have appeared, an indication of how devastating this disease can be to young mothers and their families and the urgent desire to find solutions for its cause and better treatment. The purpose of this review is to highlight the important advances that have brought us nearer to the solution of this puzzle, focusing on what we have learned about PPCM since 2000; and what still remains unanswered. Despite many improvements in outcome, we still do not know the actual triggers that initiate the pathological process; but realize that cardiac angiogenic imbalances resulting from complex pregnancy-related immune system and hormonal changes play a key role. PMID:24669290

  11. LEARNING VOCABULARY THROUGH COLOURFUL PUZZLE GAME

    Directory of Open Access Journals (Sweden)

    Risca Dwiaryanti

    2014-05-01

    Full Text Available Vocabulary plays an important role because it links to the four skills of listening, speaking, reading, and writing. Those aspects should be integrated in teaching and learning process of English. However, the students must be able to know the meaning of each word or vocabulary of English in order to master the four skills. It is as a mean to create a sentence in daily communication to show someone’s feeling, opinion, idea, desire, etc. So that, both speakers understand what the other speaker mean. However, English as a second language in Indonesia seems very hard for the students to master vocabulary of English. It makes them not easy to be understood directly and speak fluently. The students, sometimes, get difficulties in understanding, memorizing the meaning of the vocabulary, and getting confused in using the new words. There must be an effective strategy to attract students’ interest, break the boredom, and make the class more lively. Based on the writer experience, Colourful Puzzle Game is able to make the students learn vocabulary quickly. It needs teacher’s creativity to create the materials of this game based on the class condition. The teacher just need a game board made from colourful papers, write any command and prohibition words on it. A dice is a tool to decide where the player should stop based on the number. Some pins as counter as sign of each player.

  12. The Muon Scattering Experiment (MUSE at PSI and the proton radius puzzle

    Directory of Open Access Journals (Sweden)

    Kohl Michael

    2014-01-01

    Full Text Available The unexplained large discrepancy of the proton charge radius measurements with muonic hydrogen Lamb shift and determinations from elastic electron scattering and Lamb shift in regular hydrogen of seven standard deviations is known as the proton radius puzzle. Suggested solutions of the puzzle range from possible errors in the experiments through unexpectedly large hadronic physics effects to new physics beyond the Standard Model. A new approach to verify the radius discrepancy in a systematic manner will be pursued with the Muon Scattering Experiment (MUSE at PSI. The experiment aims to compare elastic cross sections, the proton elastic form factors, and the extracted proton charge radius with scattering of electrons and muons of either charge and under identical conditions. The difference in the observed radius will be probed with a high precision to verify the discrepancy. An overview of the experiment and the current status will be presented.

  13. Puzzling electron behavior analogous to the Braess paradox in a mesoscopic networ

    Science.gov (United States)

    Toussaint, Sébastien; Faniel, Sébastien; Martins, Frederico; Pala, Marco; Desplanque, Ludovic; Wallart, Xavier; Huant, Serge; Sellier, Hermann; Bayot, Vincent; Hackens, Benoit

    A counterintuitive behavior analogous to the Braess paradox is encountered in a two-terminal mesoscopic network patterned in a two-dimensional electron system (2DES). Decreasing locally the electron density of one channel in the network paradoxically leads to an increased network conductance. Our scanning gate microscopy experiments reveals this puzzling conductance variation, thanks to tip-induced localized modifications of electron flow throughout the network's channels at low temperature, in the ballistic and coherent regime of transport. We compare the amplitude of the measured anomalous conductance variation with conductance changes induced by other mechanisms at play in the mesoscopic network, such as interference phenomena between different paths, and Coulomb blockade due to disorder-induced localized states. The robustness of this puzzling behavior is inspected by varying the global 2DES density, magnetic field and temperature S.T. acknowledges support from the Belgian FRS-FNRS (FRIA).

  14. Puzzling electron behavior analogous to the Braess paradox in a mesoscopic network

    Science.gov (United States)

    Toussaint, Sébastien; Faniel, Sébastien; Martins, Frederico; Pala, Marco; Desplanque, Ludovic; Wallart, Xavier; Huant, Serge; Sellier, Hermann; Bayot, Vincent; Hackens, Benoit

    A counterintuitive behavior analogous to the Braess paradox is encountered in a two-terminal mesoscopic network patterned in a two-dimensional electron system (2DES). Decreasing locally the electron density of one channel in the network paradoxically leads to an increased network conductance. Our scanning gate microscopy experiments reveals this puzzling conductance variation, thanks to tip-induced localized modifications of electron flow throughout the network's channels at low temperature, in the ballistic and coherent regime of transport. We compare the amplitude of the measured anomalous conductance variation with conductance changes induced by other mechanisms at play in the mesoscopic network, such as interference phenomena between different paths, and Coulomb blockade due to disorder-induced localized states. The robustness of this puzzling behavior is inspected by varying the global 2DES density, magnetic field and temperature. S.T. acknowledges support from the Belgian FRS-FNRS (FRIA).

  15. Brodmann area 12: an historical puzzle relevant to FTLD.

    Science.gov (United States)

    Kawamura, M; Miller, M W; Ichikawa, H; Ishihara, K; Sugimoto, A

    2011-05-03

    Brodmann brain maps, assembled in 1909, are still in use, but understanding of their animal-human homology is uncertain. Furthermore, in 1909, Brodmann did not identify human area 12 (BA12), a location now important to understanding of frontotemporal lobar degeneration (FTLD). We re-examined Brodmann's areas, both animal and human, in his 1909 monograph and other literature, both historical and contemporary, and projected BA12 onto the medial surface of a fixed human brain to show its location. We found Brodmann did identify human BA12 in later maps (1910 and 1914), but that his brain areas, contrary to his own aims as a comparative anatomist, are now used as physiologic loci in human brain. Because of its current link with frontotemporal dementia, BA12's transition from animal (1909) to human (1910 and 1914) is not only an historical puzzle. It impacts how Brodmann's areas, based on comparative animal-human cytoarchitecture, are widely used in current research as functional loci in human brain.

  16. Local associations and the barium puzzle

    Science.gov (United States)

    Reddy, Arumalla B. S.; Lambert, David L.

    2015-12-01

    We have observed high-dispersion echelle spectra of main-sequence stars in five nearby young associations - Argus, Carina-Near, Hercules-Lyra, Orion and Subgroup B4 - and derived abundances for elements ranging from Na to Eu. These are the first chemical abundance measurements for two of the five associations, while the remaining three associations are analysed more extensively in our study. Our results support the presence of chemical homogeneity among association members with a typical star-to-star abundance scatter of about 0.06 dex or less over many elements. The five associations show log ɛ(Li) consistent with their age and share a solar chemical composition for all elements with the exception of Ba. We find that all the heavy elements (Y, Zr, La, Ce, Nd, Sm and Eu) exhibit solar ratios, i.e. [X/Fe] ≃ 0, while Ba is overabundant by about 0.2-0.3 dex. The origin of the overabundance of Ba is a puzzle. Within the formulation of the s-process, it is difficult to create a higher Ba abundance without a similar increase in the s-process contributions to other heavy elements (La-Sm). Given that Ba is represented by strong lines of Ba II and La-Sm are represented by rather weak ionized lines, the suggestion, as previously made by other studies, is that the Ba abundance may be systematically overestimated by standard methods of abundance analysis perhaps because the upper reaches of the stellar atmospheres are poorly represented by standard model atmospheres. A novel attempt to analyse the Ba I line at 5535 Å gives a solar Ba abundance for stars with effective temperatures hotter than about 5800 K but increasingly subsolar Ba abundances for cooler stars with apparent Ba deficiencies of 0.5 dex at 5100 K. This trend with temperature may signal a serious non-local thermodynamical equilibrium effect on the Ba I line.

  17. Heavy quarkonium: progress, puzzles, and opportunities

    Energy Technology Data Exchange (ETDEWEB)

    Brambilla, N; Heltsley, B K; Vogt, R; Bodwin, G T; Eichten, E; Frawley, A D; Meyer, A B; Mitchell, R E; Papdimitriou, V; Petreczky, P; Petrov, A A; Robbe, P; Vairo, A; Andronic, A; Arnaldi, R; Artoisenet, P; Bali, G; Bertolin, A; Bettoni, D; Brodzicka, J; Bruno, G E; Caldwell, A; Catmore, J; Chang, C -H; Chao, K -T; Chudakov, E; Cortese, P; Crochet, P; Drutskoy, A; Ellwanger, U; Faccioli, P; Gabareen Mokhtar, A; Garcia i Tormo, X; Hanhart, C; Harris, F A; Kaplan, D M; Klein, S R; Kowalski, H; Lansberg, J -P; Levichev, E; Lombardo, V; Loureno, C; Maltoni, F; Mocsy, A; Mussa, R; Navarra, F S; Negrini, M; Nielsen, M; Olsen, S L; Pakhlov, P; Pakhlova, G; Peters, K; Polosa, A D; Qian, W; Qiu, J -W; Rong, G; Sanchis-Lozano, M A; Scomparin, E; Senger, P; Simon, F; Stracka, S; Sumino, Y; Voloshin, M; Weiss, C; Wohri, H K; Yuan, C -Z

    2011-02-01

    A golden age for heavy quarkonium physics dawned a decade ago, initiated by the confluence of exciting advances in quantum chromodynamics (QCD) and an explosion of related experimental activity. The early years of this period were chronicled in the Quarkonium Working Group (QWG) CERN Yellow Report (YR) in 2004, which presented a comprehensive review of the status of the field at that time and provided specific recommendations for further progress. However, the broad spectrum of subsequent breakthroughs, surprises, and continuing puzzles could only be partially anticipated. Since the release of the YR, the BESII program concluded only to give birth to BESIII; the $B$-factories and CLEO-c flourished; quarkonium production and polarization measurements at HERA, JLab, and the Tevatron matured; and heavy-ion collisions at RHIC have opened a window on the deconfinement regime. All these experiments leave legacies of quality, precision, and unsolved mysteries for quarkonium physics, and therefore beg for continuing investigations. The plethora of newly-found quarkonium-like states unleashed a flood of theoretical investigations into new forms of matter such as quark-gluon hybrids, mesonic molecules, and tetraquarks. Measurements of the spectroscopy, decays, production, and in-medium behavior of c\\bar{c}, b\\bar{b}, and b\\bar{c} bound states have been shown to validate some theoretical approaches to QCD and highlight lack of quantitative success for others. The intriguing details of quarkonium suppression in heavy-ion collisions that have emerged from RHIC have elevated the importance of separating hot- and cold-nuclear-matter effects in quark-gluon plasma studies. This review systematically addresses all these matters and concludes by prioritizing directions for ongoing and future efforts.

  18. Is the proton radius puzzle evidence of extra dimensions?

    Energy Technology Data Exchange (ETDEWEB)

    Dahia, F.; Lemos, A.S. [Universidade Federal da Paraiba, Department of Physics, Joao Pessoa, PB (Brazil)

    2016-08-15

    The proton charge radius inferred from muonic hydrogen spectroscopy is not compatible with the previous value given by CODATA-2010, which, on its turn, essentially relies on measurements of the electron-proton interaction. The proton's new size was extracted from the 2S-2P Lamb shift in the muonic hydrogen, which showed an energy excess of 0.3 meV in comparison to the theoretical prediction, evaluated with the CODATA radius. Higher-dimensional gravity is a candidate to explain this discrepancy, since the muon-proton gravitational interaction is stronger than the electron-proton interaction and, in the context of braneworld models, the gravitational potential can be hugely amplified in short distances when compared to the Newtonian potential. Motivated by these ideas, we study a muonic hydrogen confined in a thick brane. We show that the muon-proton gravitational interaction modified by extra dimensions can provide the additional separation of 0.3 meV between the 2S and 2P states. In this scenario, the gravitational energy depends on the higher-dimensional Planck mass and indirectly on the brane thickness. Studying the behavior of the gravitational energy with respect to the brane thickness in a realistic range, we find constraints for the fundamental Planck mass that solve the proton radius puzzle and are consistent with previous experimental bounds. (orig.)

  19. International trade network: fractal properties and globalization puzzle.

    Science.gov (United States)

    Karpiarz, Mariusz; Fronczak, Piotr; Fronczak, Agata

    2014-12-12

    Globalization is one of the central concepts of our age. The common perception of the process is that, due to declining communication and transport costs, distance becomes less and less important. However, the distance coefficient in the gravity model of trade, which grows in time, indicates that the role of distance increases rather than decreases. This, in essence, captures the notion of the globalization puzzle. Here, we show that the fractality of the international trade system (ITS) provides a simple solution for the puzzle. We argue that the distance coefficient corresponds to the fractal dimension of ITS. We provide two independent methods, the box counting method and spatial choice model, which confirm this statement. Our results allow us to conclude that the previous approaches to solving the puzzle misinterpreted the meaning of the distance coefficient in the gravity model of trade.

  20. International trade network: fractal properties and globalization puzzle

    CERN Document Server

    Karpiarz, Mariusz; Fronczak, Agata

    2014-01-01

    Globalization is one of the central concepts of our age. The common perception of the process is that, due to declining communication and transport costs, distance becomes less and less important. However, the distance coefficient in the gravity model of trade, which grows in time, indicates that the role of distance increases rather than decreases. This, in essence, captures the notion of the globalization puzzle. Here, we show that the fractality of the international trade system (ITS) provides a simple solution for the puzzle. We argue, that the distance coefficient corresponds to the fractal dimension of ITS. We provide two independent methods, box counting method and spatial choice model, which confirm this statement. Our results allow us to conclude that the previous approaches to solving the puzzle misinterpreted the meaning of the distance coefficient in the gravity model of trade.

  1. Lorentz violation in the gravity sector: the t puzzle

    CERN Document Server

    Bonder, Yuri

    2015-01-01

    Lorentz violation is a candidate quantum-gravity signal, and the Standard-Model Extension (SME) is a widely used parametrization of such violation. In the gravitational SME sector, there is an elusive coefficient for which no effects have been found. This is is known as the $t$ puzzle and, to date, it has no compelling explanation. In this paper, several approaches to understand the $t$ puzzle are proposed. First, redefinitions of the dynamical fields are studied, which reveal that other SME coefficients can be moved to nongravitational sectors. It is also shown that the gravity SME sector can be treated \\textit{\\`a la} Palatini, and that, in the presence of spacetime boundaries, it is possible to correct its action to get the desired equations of motion. Also, through a reformulation as a Lanczos-type tensor, some problematic features of the $t$ term, that should arise at the phenomenological level, are revealed. Additional potential explanations to the $t$ puzzle are outlined.

  2. The equity premium puzzle and emotional asset pricing

    OpenAIRE

    Gürtler, Marc; Hartmann, Nora

    2004-01-01

    "Since the equity premium as well as the risk-free rate puzzle question the concepts central to financial and economic modeling, we apply behavioral decision theory to asset pricing in view of solving these puzzles. U.S. stock market data for the period 1960-2003 and German stock market data for the period 1977-2003 show that emotional investors who act in accordance to Bell's (1985) disappointment theory -a special case of prospect theory- and additionally administer mental accounts demand a...

  3. The Effect of Monetary Policy on Exchange Rates : How to Solve the Puzzles

    NARCIS (Netherlands)

    Kumah, F.Y.

    1996-01-01

    Recent empirical research on the effects of monetary policy shocks on exchange rate fluctuations have encountered the exchange rate puzzle and th e forward discount bias puzzle.The exchange rate puzzle is the tendency of the domestic currency (of non-US G-7 countries) to depreciate against the US

  4. Puzzles in modern biology. I. Male sterility, failure reveals design [version 1; referees: 2 approved

    Directory of Open Access Journals (Sweden)

    Steven A. Frank

    2016-09-01

    Full Text Available Many human males produce dysfunctional sperm. Various plants frequently abort pollen. Hybrid matings often produce sterile males. Widespread male sterility is puzzling. Natural selection prunes reproductive failure. Puzzling failure implies something that we do not understand about how organisms are designed. Solving the puzzle reveals the hidden processes of design.

  5. Teaching Proofs and Algorithms in Discrete Mathematics with Online Visual Logic Puzzles

    Science.gov (United States)

    Cigas, John; Hsin, Wen-Jung

    2005-01-01

    Visual logic puzzles provide a fertile environment for teaching multiple topics in discrete mathematics. Many puzzles can be solved by the repeated application of a small, finite set of strategies. Explicitly reasoning from a strategy to a new puzzle state illustrates theorems, proofs, and logic principles. These provide valuable, concrete…

  6. The Effect of Monetary Policy on Exchange Rates : How to Solve the Puzzles

    NARCIS (Netherlands)

    Kumah, F.Y.

    1996-01-01

    Recent empirical research on the effects of monetary policy shocks on exchange rate fluctuations have encountered the exchange rate puzzle and th e forward discount bias puzzle.The exchange rate puzzle is the tendency of the domestic currency (of non-US G-7 countries) to depreciate against the US do

  7. Some Lessons from Kripke's A Puzzle About Belief

    African Journals Online (AJOL)

    KATEVG

    Keywords: Kripke, Pierre-puzzle, propositional attitude contexts, epistemic .... cannot be denied either, despite his French background. If Pierre suddenly gets an electric shock that wipes out all his memories of the French language he would be in the ... Because of this, he is inclined to assent to Paderewski had musical.

  8. Games and puzzles for English as a second language

    CERN Document Server

    Fremont, Victoria

    2011-01-01

    Students can hone their verbal and grammatical skills with this entertaining workbook. Search-a-words, crossword puzzles, anagrams, and other challenges build vocabulary and spelling skills. They also help students understand and identify idioms, irregular past tenses and participles, and other linguistic stumbling blocks. Perfect for individual study or as a course supplement.

  9. The puzzling resilience of transnational organized criminal networks

    DEFF Research Database (Denmark)

    Leuprecht, Christian; Aulthouse, Andrew; Walther, Olivier

    2016-01-01

    international organized crime syndicate based in Jamaica, whose resilience proves particularly puzzling. We were curious to know whether there is any evidence that international borders have an effect on the structure of illicit networks that cross them. It turns out that transnational drug distribution...

  10. Asset pricing puzzles explained by incomplete Brownian equilibria

    DEFF Research Database (Denmark)

    Christensen, Peter Ove; Larsen, Kasper

    We examine a class of Brownian based models which produce tractable incomplete equilibria. The models are based on finitely many investors with heterogeneous exponential utilities over intermediate consumption who receive partially unspanned income. The investors can trade continuously on a finit...... markets. Consequently, our model can simultaneously help explaining the risk-free rate and equity premium puzzles....

  11. Unraveling "Braid": Puzzle Games and Storytelling in the Imperative Mood

    Science.gov (United States)

    Arnott, Luke

    2012-01-01

    "Unraveling Braid" analyzes how unconventional, non-linear narrative fiction can help explain the ways in which video games signify. Specifically, this essay looks at the links between the semiotic features of Jonathan Blow's 2008 puzzle-platform video game Braid and similar elements in Georges Perec's 1978 novel "Life A User's Manual," as well as…

  12. Puzzling with potential : dynamic testing of analogical reasoning in children

    NARCIS (Netherlands)

    Stevenson, Claire Elisabeth

    2012-01-01

    Assessment procedures are frequent in children's school careers; however, measuring potential for learning has remained a puzzle. Dynamic testing is a method to assess cognitive potential that includes training in the assessment process. The goal of this thesis project was to develop a new dynamic

  13. Ambiguity Aversion and Household Portfolio Choice Puzzles: Empirical Evidence

    NARCIS (Netherlands)

    S.G. Dimmock (Stephen); R.R.P. Kouwenberg (Roy); O.S. Mitchell (Olivia); K. Peijnenburg (Kim)

    2016-01-01

    markdownabstractWe test the relation between ambiguity aversion and five household portfolio choice puzzles: nonparticipation in equities, low allocations to equity, home-bias, own-company stock ownership, and portfolio under-diversification. In a representative US household survey, we measure ambig

  14. A Jigsaw Puzzle Approach To Learning History in Introductory Psychology.

    Science.gov (United States)

    Krauss, Judith

    1999-01-01

    Believes that it may be daunting for some students to learn about the history of psychology. Describes a teaching strategy that uses jigsaw puzzles to teach about the historical terms of structuralism, functionalism, and gestalt psychology. Finds that students performed better on test questions related to these three concepts after using this…

  15. Precautionary Borrowing and the Credit Card Debt Puzzle

    DEFF Research Database (Denmark)

    Druedahl, Jeppe; Jørgensen, Casper Nordal

    2015-01-01

    This paper addresses the credit card debt puzzle using a generalization of the buffer-stock consumption model with long-term revolving debt contracts. Closely resembling actual US credit card law, we assume that card issuers can always deny their cardholders access to new debt, but that they cannot...

  16. A Geometric Puzzle That Leads To Fibonacci Sequences.

    Science.gov (United States)

    Rulf, Benjamin

    1998-01-01

    Illustrates how mathematicians work and do mathematical research through the use of a puzzle. Demonstrates how general rules, then theorems develop from special cases. This approach may be used as a research project in high school classrooms or math club settings with the teacher helping to formulate questions, set goals, and avoid becoming…

  17. Update On the Puzzling Boyajian's Star

    Science.gov (United States)

    Kohler, Susanna

    2016-09-01

    Photometric time series for a neighboring star thats 25 NNW of Boyajians Star. No significant long-term dimming is seen which constrains the size of potential material obscuring Boyajians Star. [Wright et al. 2016/Benjamin Montet]Whats causing the mysterious light-curve dips of the so-called alien megastructure star, Boyajians Star? A recent study analyzes a variety of possible explanations to determine which ones are the most plausible.An Unusual Light CurveEarlier this year, astronomer Tabetha Boyajian reported on the unusual light curve of the star KIC 8462852. This star, now nicknamed Tabbys Star or Boyajians Star, showsunusual dips on day-long timescales that are too large to be explained by planet transits or similar phenomena.In addition to these short dips in luminosity, recent observations have also indicated that the star has faded by roughly 20% over the past hundred years. What could be causing both the short-term dips in the stars light and the long-term dimming over a century?Could the dimming be caused by an alien megastructure built by an extraterrestrial civilization? The authors find that a spherical structure is very unlikely. [Danielle Futselaar/SETI International]Alien Megastructures? Or Another Explanation?Boyajians Star was vaulted into the media spotlight when astronomer Jason Wright (Pennsylvania State University and University of California, Berkeley) proposed that its unusual light curve could potentially be explained by a surrounding megastructure built by an extraterrestrial civilization.Now Wright is back with co-author Steinn Sigurdsson (Pennsylvania State University). In a new study, Wright and Sigurdsson analyze an extensive list of explanations for the puzzling apparent behavior of Boyajians Star, based on our latest knowledge about this strange object.The Realm of PossibilitiesHere are just a few possible causes of Boyajians Stars dimming, as well as the authors assessment of their plausibility. For the full list, see the authors

  18. Four small puzzles that Rosetta doesn't solve.

    Directory of Open Access Journals (Sweden)

    Rhiju Das

    Full Text Available A complete macromolecule modeling package must be able to solve the simplest structure prediction problems. Despite recent successes in high resolution structure modeling and design, the Rosetta software suite fares poorly on small protein and RNA puzzles, some as small as four residues. To illustrate these problems, this manuscript presents Rosetta results for four well-defined test cases: the 20-residue mini-protein Trp cage, an even smaller disulfide-stabilized conotoxin, the reactive loop of a serine protease inhibitor, and a UUCG RNA tetraloop. In contrast to previous Rosetta studies, several lines of evidence indicate that conformational sampling is not the major bottleneck in modeling these small systems. Instead, approximations and omissions in the Rosetta all-atom energy function currently preclude discriminating experimentally observed conformations from de novo models at atomic resolution. These molecular "puzzles" should serve as useful model systems for developers wishing to make foundational improvements to this powerful modeling suite.

  19. Asset pricing puzzles explained by incomplete Brownian equilibria

    DEFF Research Database (Denmark)

    Christensen, Peter Ove; Larsen, Kasper

    time interval in a money market account as well as a risky security. Besides establishing the existence of an equilibrium, our main result shows that the resulting equilibrium can display a lower risk-free rate and a higher risk premium relative to the usual Pareto efficient equilibrium in complete...... markets. Consequently, our model can simultaneously help explaining the risk-free rate and equity premium puzzles....

  20. The Puzzle of a Marble in a Spinning Pipe

    Science.gov (United States)

    2015-05-01

    MAY 2015 2. REPORT TYPE 3. DATES COVERED 00-00-2015 to 00-00-2015 4. TITLE AND SUBTITLE The Puzzle of a Marble in a Spinning Pipe 5a. CONTRACT...inside a rotating pipe and then suddenly released? 15. SUBJECT TERMS 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT Same as Report (SAR... pipe (of slightly larger diameter than the marble) and held there by a catch. The pipe is glued to a rotating turntable having frictionless bearings

  1. Experimental status and prospects of the "Kpi puzzle"

    CERN Document Server

    Unno, Yuuji

    2011-01-01

    We present a summary of the latest measurements of branching fractions and direct CP violations in the charmless hadronic two-body B decays B -> K^+ pi^-, K^+ pi^0, K^0 pi^+ and K^0 pi^0, performed by the Belle, BABAR, CDF and CLEO experiments. The interpretations and the future prospects about discrepancies, called "Kpi puzzle", between theoretical expectations and measurements are discussed.

  2. Pension Demand and Utility: The Life Annuity Puzzle

    OpenAIRE

    Tomáš Cipra

    2014-01-01

    This paper shows by means of the concept of utility that annuitization through life annui-ties or a pension can be an efficient instrument for the economic assurance of seniors. Various quantitative arguments are presented supporting this statement (e.g. annuity equivalent wealth [AEW] is calculated using Czech data). In conclusion, some practical arguments are mentioned regarding why the real demand on life annuities contradicts this result so that a so-called annuity puzzle arises in pensio...

  3. Puzzles, paradoxes, and problem solving an introduction to mathematical thinking

    CERN Document Server

    Reba, Marilyn A

    2014-01-01

    Graphs: Puzzles and Optimization Graphical Representation and Search Greedy Algorithms and Dynamic Programming Shortest Paths, DNA Sequences, and GPS Systems Routing Problems and Optimal Circuits Traveling Salesmen and Optimal Orderings Vertex Colorings and Edge Matchings Logic: Rational Inference and Computer Circuits Inductive and Deductive Arguments Deductive Arguments and Truth-Tables Deductive Arguments and Derivations Deductive Logic and Equivalence Modeling Using Deductive Logic Probability: Predictions and Expectations Probability and Counting Counting and Unordered Outcomes Independen

  4. PUZZLES – A CREATIVE WAY OF DEVELOPMENT OF LOGICAL THINKING

    Directory of Open Access Journals (Sweden)

    Milková, Eva

    2011-12-01

    Full Text Available Logical thinking of students should be enhanced at all levels of their studies. There are many possibilities how to achieve it. In the paper one possible way within the subjects “Discrete Mathematics” and “Discrete Methods and Optimization” dealing with graph theory and combinatorial optimization will be presented. These mathematical disciplines are powerful tools for teachers allowing them to develop logical thinking of students, increase their imagination and make them familiar with solutions to various problems. Thanks the knowledge gained within the subjects students should be able to describe various practical situations with the aid of graphs, solve the given problem expressed by the graph, and translate the solution back into the initial situation. Student engagement is crucial for successful education. Practical tasks and puzzles attract students to know more about the explained subject matter and to apply gained knowledge. There are an endless number of enjoyable tasks, puzzles and logic problems in books like “Mathematics is Fun”, in riddles magazines and on the Internet. In the paper, as an inspiration, four puzzles developing logical thinking appropriate to be solved using graph theory and combinatorial optimization will be introduced. On these puzzles of different level of difficulty the students’ ability to find out the appropriate graph-representation of the given task and solve it will be discussed as well. The author of the paper has been prepared with her students various multimedia applications dealing with objects appropriate to subject matter for more than 15 years. In the paper we also discuss a benefit of multimedia applications used as a support of subjects “Discrete Mathematics” and “Discrete Methods and Optimization”.

  5. The Feldstein-Horioka puzzle and transition economies

    Directory of Open Access Journals (Sweden)

    Petreska Despina

    2013-01-01

    Full Text Available The objective of this paper is to investigate the existence of the Feldstein and Horioka puzzle in transition countries, divided into three groups of countries: South-East Europe (SEE, Central and Eastern Europe (CEE, and the Commonwealth of Independent States (CIS. Central to this puzzle is the β coefficient, which measures the relationship between domestic savings and investment. In their seminal paper from 1980 Feldstein and Horioka estimated a value of the β coefficient close to 1, which in their opinion indicates low capital mobility as opposed to the theory and the conventional wisdom of perfect capital mobility. We use annual data for the period 1991-2010 and panel cointegration econometric technique to examine this relationship in three panels of countries (SEE, CEE, and CIS. We find that the puzzle of Feldstein and Horioka exists in all three panels, but the connection between savings and investment is generally lower than 1. As we move towards a panel composed of the larger and richer countries the value of the β coefficient increases. Moreover, the coefficient of adjustment of the disequilibrium between domestic savings and investment is positive in all cases, indicating that any imbalance between savings and investment is not corrected immediately.

  6. Supersymmetry, the flavour puzzle and rare B decays

    Energy Technology Data Exchange (ETDEWEB)

    Straub, David Michael

    2010-07-14

    The gauge hierarchy problem and the flavour puzzle belong to the most pressing open questions in the Standard Model of particle physics. Supersymmetry is arguably the most popular framework of physics beyond the Standard Model and provides an elegant solution to the gauge hierarchy problem; however, it aggravates the flavour puzzle. In the first part of this thesis, I discuss several approaches to address the flavour puzzle in the minimal supersymmetric extension of the Standard Model and experimental tests thereof: supersymmetric grand unified theories with a unification of Yukawa couplings at high energies, theories with minimal flavour violation and additional sources of CP violation and theories with gauge mediation of supersymmetry breaking and a large ratio of Higgs vacuum expectation values. In the second part of the thesis, I discuss the phenomenology of two rare B meson decay modes which are promising probes of physics beyond the Standard Model: The exclusive B {yields} K{sup *}l{sup +}l{sup -} decay, whose angular decay distribution will be studied at LHC and gives access to a large number of observables and the b{yields}s{nu}anti {nu} decays, which are in the focus of planned high-luminosity Super B factories. I discuss the predictions for these observables in the Standard Model and their sensitivity to New Physics. (orig.)

  7. 3D satellite puzzles for young and old kids

    Science.gov (United States)

    Biondi, Riccardo; Galoforo, Germana

    2017-04-01

    The Italian Space Agency (ASI) is active in outreach willing to increase the interest of young generations and general public toward the space activities. ASI proposes educational programmes for supporting and encouraging the development of European society based on knowledge, inspiring and motivating the young generations. One of the initiatives promoted by ASI on this regards is the 3D satellite puzzles. The idea was born in 2007 from the will to conceive an educational product for promoting and explaining to students the small all-Italian mission AGILE (Astrorivelatore Gamma ad Immagini ultra Leggero) thought as a tool for students aged 8-13. Working with this slot of students is very productive in terms of the imprints left on the kids, in fact it is useful to produce things they can use, touch and play with, with an active approach instead of a passive one. Therefore it was decided to produce something that kids could build and use at home with their parents or friends, or all together at school with teachers and mates. Other puzzles followed AGILE, one about the COSMO-SkyMED satellites about Earth Observation and also a broader one of the International Space Station. During these 10 years the puzzles were mostly used as outreach tools for school children, but they surprisingly received a great success also within older generations. So far the 3D puzzles have been printed in more than 10 thousand copies and distributed for free to students of hundreds of schools in Italy, and to the general public through science associations, planetaria and museums. Recently they have been used also during special events such as the international Geoscience Communication School (as best practice outreach tool), the EXPO 2015 and the European Researcheŕs Night at the Parlamentarium in Brussels 2016. While the students are building the puzzles, the tutor explains them the different components that they are assembling, what the importance of the satellite is and how it works

  8. Management of Strongyloides stercoralis: a puzzling parasite.

    Science.gov (United States)

    Luvira, Viravarn; Watthanakulpanich, Dorn; Pittisuttithum, Punnee

    2014-12-01

    Strongyloides stercoralis is one of the common parasites in tropical areas. It can result in severe clinical syndromes, hyperinfection syndrome or disseminated strongyloidiasis in immunocompromised patients. The treatment of strongyloidiasis is a challenge for clinicians in clinical practice. Failure of treatment is due to autoinfection caused by the parasite life cycle and impairment of host immunity. Ivermectin currently is the treatment of choice. When compared with thiabendazole, it has shown a similar efficacy with better tolerability. However, there is neither consensus in duration of treatment nor in repetition of doses. The keys for management of this tough parasite include proper evaluation and prevention. Stool examination with high sensitivity techniques such as Baermann technique, filter-paper culture and agar-plate culture and specific IgG serology should be used in evaluation for 1 to 2 years. Screening, both stool examination and serology, before patients have immunosuppressive treatment is needed to prevent the severe form of strongyloidiasis.

  9. The Puzzling Spectrum of HD 94509

    CERN Document Server

    Cowley, C R; Hubrig, S

    2015-01-01

    The spectral features of HD 94509 are highly unusual, adding an extreme to the zoo of Be and shell stars. The shell dominates the spectrum, showing lines typical for spectral types mid-A to early-F, while the presence of a late/mid B-type central star is indicated by photospheric hydrogen line wings and helium lines. Numerous metallic absorption lines have broad wings but taper to narrow cores. They cannot be fit by Voigt profiles. We aim to describe and illustrate unusual spectral features of this star, and make rough calculations to estimate physical conditions and abundances in the shell. Furthermore, the central star is characterized. We assume mean conditions for the shell. An electron density estimate is made from the Inglis-Teller formula. Excitation temperatures and column densities for Fe I and Fe II are derived from curves of growth. The neutral H column density is estimated from high Paschen members. The column densities are compared with calculations made with the photoionization code Cloudy. Atmo...

  10. QALYs, euthanasia and the puzzle of death.

    Science.gov (United States)

    Barrie, Stephen

    2015-08-01

    This paper considers the problems that arise when death, which is a philosophically difficult concept, is incorporated into healthcare metrics, such as the quality-adjusted life year (QALY). These problems relate closely to the debate over euthanasia and assisted suicide because negative QALY scores can be taken to mean that patients would be 'better off dead'. There is confusion in the literature about the meaning of 0 QALY, which is supposed to act as an 'anchor' for the surveyed preferences on which QALYs are based. In the context of the debate over euthanasia, the QALY assumes an ability to make meaningful comparisons between life-states and death. Not only is this assumption questionable, but the ethical debate is much more broad than the question of whether death is preferable to a state of living. QALYs are derived from preferences about health states, so do not necessarily reflect preferences about events (eg, dying) or actions (eg, killing). This paper presents a new kind of problem for the QALY. As it stands, the QALY provides confused and unreliable information when it reports zero or negative values, and faces further problems when it appears to recommend death. This should preclude its use in the debate over euthanasia and assisted suicide. These problems only apply where the QALY involves or seems to involve a comparison between life-states and death, and are not relevant to the more general discussion of the use of QALYs as a tool for comparing the benefits derived from treatment options. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  11. Precautionary Borrowing and the Credit Card Debt Puzzle

    DEFF Research Database (Denmark)

    Druedahl, Jeppe; Jørgensen, Casper Nordal

    2015-01-01

    This paper addresses the credit card debt puzzle using a generalization of the buffer-stock consumption model with long-term revolving debt contracts. Closely resembling actual US credit card law, we assume that card issuers can always deny their cardholders access to new debt, but that they cannot...... to simultaneously hold positive gross debt and positive gross assets even though the interest rate on the debt is much higher than the return rate on the assets. Including a risk of being excluded from new borrowing which is positively correlated with unemployment, we are able to simultaneously explain...

  12. A Dynamical Resolution of the Sigma Term Puzzle

    CERN Document Server

    Ball, R D; Tigg, J; Ball, Richard D.; Forte, Stefano; Tigg, Jason

    1994-01-01

    We propose a resolution of the puzzle posed by the discrepancy between the pion-nucleon sigma term inferred from pion-nucleon scattering, and that deduced from baryon mass splittings using the Zweig rule. We show that there is a significant hypercharge-dependent dynamical contribution to baryon masses, not hitherto included in the analysis, which may be estimated using the scale Ward identity, and computed by solution of the Schwinger-Dyson equation for the quark self-energy. We find that the discrepancy is completely resolved without the need for any Zweig rule violation.

  13. The Long Slow Death of the HBT Puzzle

    CERN Document Server

    Pratt, Scott

    2008-01-01

    Femtoscopic measurements at RHIC have been hailed as a source of insight into the bulk properties of QCD matter. However, hydrodynamic models, which have been successful in reproducing other observables have failed to satisfactorily explain femtoscopic two-particle correlation measurements. This failure has been labeled the "HBT puzzle". In this talk, I present correlations using a hybrid model composed of a viscous hydrodynamic module and a hadronic cascade. After incorporating early acceleration, viscosity and a stiffer equation of state, the extracted source sizes come much closer to experiment.

  14. Anisotropic hydrodynamics and the early-thermalization puzzle

    CERN Document Server

    Florkowski, Wojciech

    2012-01-01

    The framework of anisotropic hydrodynamics is used in 3+1 dimensions to analyze behavior of matter produced in ultra-relativistic heavy-ion collisions. The model predictions for the hadronic transverse-momentum spectra, directed and elliptic flows, and the HBT radii are presented. We show that the effects of the initial anisotropy of pressure may be compensated by appropriate adjustment of the initial energy density. In this way, the final hadronic observables become insensitive to the early stage dynamics and the early thermalization puzzle may be circumvented.

  15. Solving Solar Neutrino Puzzle via LMA MSW Conversion

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    We analyze the existing solar neutrino experiment data and show the allowed regions. The result from SNO's salt phase itself restricts quite a lot the allowed region's area. Reactor neutrinos play an important role in determining oscillation parameters. KamLAND gives decisive conclusion on the solution to the solar neutrino puzzle, in particular, the spectral distortion in the 766.3 Ty KamLAND data gives another new improvement in the constraint of solar MSW-LMA solutions. We confirm that at 99. 73% C.L. the high-LMA solution is excluded.

  16. The puzzle of non-proliferation and disarmament; El puzzle de la No-Proliferacion y el Desarme (primera parte)

    Energy Technology Data Exchange (ETDEWEB)

    Ponga, J. de

    2011-07-01

    Since, in 1945, the World was aware of the devastating power of nuclear weapons, there have been many initiatives at international level to avoid nuclear weapon proliferation: the foundation of the IAEA, the NPT, the Safeguards Agreements, the Nuclear Weapon Free Zones, the treaties banning nuclear tests or the export control regime of the NSG, among others. This article aims to offer a general picture of all of them as pieces of a puzzle the purpose of which is not to allow gaps to non pacific uses of nuclear energy. (Author)

  17. The puzzling unsolved mysteries of liquid water: Some recent progress

    Science.gov (United States)

    Stanley, H. E.; Kumar, P.; Xu, L.; Yan, Z.; Mazza, M. G.; Buldyrev, S. V.; Chen, S.-H.; Mallamace, F.

    2007-12-01

    Water is perhaps the most ubiquitous, and the most essential, of any molecule on earth. Indeed, it defies the imagination of even the most creative science fiction writer to picture what life would be like without water. Despite decades of research, however, water's puzzling properties are not understood and 63 anomalies that distinguish water from other liquids remain unsolved. We introduce some of these unsolved mysteries, and demonstrate recent progress in solving them. We present evidence from experiments and computer simulations supporting the hypothesis that water displays a special transition point (which is not unlike the “tipping point” immortalized by Malcolm Gladwell). The general idea is that when the liquid is near this “tipping point,” it suddenly separates into two distinct liquid phases. This concept of a new critical point is finding application to other liquids as well as water, such as silicon and silica. We also discuss related puzzles, such as the mysterious behavior of water near a protein.

  18. An ecological examination of rapport using a dyadic puzzle task.

    Science.gov (United States)

    Grahe, Jon E; Sherman, Ryne A

    2007-10-01

    Previous studies have indicated that situational context impacts the rapport experience (e.g., F. J. Bernieri, J. S. Gillis, J. M. Davis, & J. E. Grahe, 1996; N. M. Puccinelli, L. Tickle-Degnen, & R. Rosenthal, 2003). The authors designed the present study to further document the behavioral and experiential predictors of dyadic rapport and to evaluate dyadic rapport experiences when contributions were required from both interactants. Participants (N = 60) were paired into dyads and instructed to complete children's puzzles. However, the dyadic members were restricted in how they could accomplish this task: Only one interactant was allowed to work on the puzzle and had to do so blindfolded, while the second interactant gave instructions. Results suggested that less attribution of responsibility to the worker and the instructor's experience of enjoyment and frustration were indicative of higher rapport. Other characteristics of dyads reporting higher dyadic rapport included difficulty completing the task and more communicative behavior. The results provide important information for the understanding of the dyadic experience of rapport.

  19. Crossword Puzzle Makes It Fun: Introduce Green Manufacturing in Wood Technology Courses

    Science.gov (United States)

    Iley, John L.; Hague, Doug

    2012-01-01

    Sustainable, or "green," manufacturing and its practices are becoming more and more a part of today's industry, including wood product manufacturing. This article provides introductory information on green manufacturing in wood technology and a crossword puzzle based on green manufacturing terms. The authors use the puzzle at the college level to…

  20. Using the Tower of Hanoi Puzzle to Infuse Your Mathematics Classroom with Computer Science Concepts

    Science.gov (United States)

    Marzocchi, Alison S.

    2016-01-01

    This article suggests that logic puzzles, such as the well-known Tower of Hanoi puzzle, can be used to introduce computer science concepts to mathematics students of all ages. Mathematics teachers introduce their students to computer science concepts that are enacted spontaneously and subconsciously throughout the solution to the Tower of Hanoi…

  1. Crossword Puzzle Makes It Fun: Introduce Green Manufacturing in Wood Technology Courses

    Science.gov (United States)

    Iley, John L.; Hague, Doug

    2012-01-01

    Sustainable, or "green," manufacturing and its practices are becoming more and more a part of today's industry, including wood product manufacturing. This article provides introductory information on green manufacturing in wood technology and a crossword puzzle based on green manufacturing terms. The authors use the puzzle at the college level to…

  2. Using the Tower of Hanoi Puzzle to Infuse Your Mathematics Classroom with Computer Science Concepts

    Science.gov (United States)

    Marzocchi, Alison S.

    2016-01-01

    This article suggests that logic puzzles, such as the well-known Tower of Hanoi puzzle, can be used to introduce computer science concepts to mathematics students of all ages. Mathematics teachers introduce their students to computer science concepts that are enacted spontaneously and subconsciously throughout the solution to the Tower of Hanoi…

  3. The King and Prisoner Puzzle: A Way of Introducing the Components of Logical Structures

    Science.gov (United States)

    Roh, Kyeong Hah; Lee, Yong Hah; Tanner, Austin

    2016-01-01

    The purpose of this paper is to provide issues related to student understanding of logical components that arise when solving word problems. We designed a logic problem called the King and Prisoner Puzzle--a linguistically simple, yet logically challenging problem. In this paper, we describe various student solutions to the puzzle and discuss the…

  4. An anchored framework BAC map of mouse chromosome 11 assembled using multiplex oligonucleotide hybridization.

    Science.gov (United States)

    Cai, W W; Reneker, J; Chow, C W; Vaishnav, M; Bradley, A

    1998-12-15

    Despite abundant library resources for many organisms, physical mapping of these organisms has been seriously limited due to lack of efficient library screening techniques. We have developed a highly efficient strategy for large-scale screening of genomic libraries based on multiplex oligonucleotide hybridization on high-density genomic filters. We have applied this strategy to generate a bacterial artificial chromosome (BAC) anchored map of mouse chromosome 11. Using the MIT mouse SSLP data, 320 pairs of oligonucleotide probes were designed with an "overgo" computer program that selects new primer sequences that avoid the microsatellite repeat. BACs identified by these probes are automatically anchored to the chromosome. Ninety-two percent of the probes identified positive clones from a 5.9-fold coverage mouse BAC library with an average of 7 positive clones per marker. An average of 4.2 clones was confirmed for 204 markers by PCR. Our data show that a large number of clones can be efficiently isolated from a large genomic library using this strategy with minimal effort. This strategy will have wide application for large-scale mapping and sequencing of human and other large genomes.

  5. A high-resolution PAC and BAC map of the SCA2 region.

    Science.gov (United States)

    Nechiporuk, T; Nechiporuk, A; Sahba, S; Figueroa, K; Shibata, H; Chen, X N; Korenberg, J R; de Jong, P; Pulst, S M

    1997-09-15

    The spinocerebellar ataxia type 2 (SCA2) gene has been localized to chromosome 12q24.1. To characterize this region and to aid in the identification of the SCA2 gene, we have constructed a 3.9-Mb physical map, which covers markers D12S1328 and D12S1329 known to flank the gene. The map comprises a contig of 84 overlapping yeast artificial chromosomes (YACs), P1 artificial chromosomes (PACs), and bacterial artificial chromosomes (BACs) onto which we placed 82 PCR markers. We localized eight genes and expressed sequence tags on this map, many of which had not been precisely mapped before. In contrast to YACs, which showed a high degree of chimerism and deletions in this region, PACs and BACs were stable. Only 1 in 65 PACs contained a small deletion, and 2 in 18 BACs were chimeric. The high-resolution physical map, which was used in the identification of the SCA2 gene, will be useful for the positional cloning of other disease genes mapped to this region.

  6. Interfacial depinning transitions in disordered media: revisiting an old puzzle

    Science.gov (United States)

    Moglia, Belén; Albano, Ezequiel V.; Villegas, Pablo; Muñoz, Miguel A.

    2014-10-01

    Interfaces advancing through random media represent a number of different problems in physics, biology and other disciplines. Here, we study the pinning/depinning transition of the prototypical non-equilibrium interfacial model, i.e. the Kardar-Parisi-Zhang equation, advancing in a disordered medium. We analyze separately the cases of positive and negative non-linearity coefficients, which are believed to exhibit qualitatively different behavior: the positive case shows a continuous transition that can be related to directed-percolation-depinning while in the negative case there is a discontinuous transition and faceted interfaces appear. Some studies have argued from different perspectives that both cases share the same universal behavior. Here, by using a number of computational and scaling techniques we shed light on this puzzling situation and conclude that the two cases are intrinsically different.

  7. SybilControl: Practical Sybil Defense with Computational Puzzles

    CERN Document Server

    Li, Frank; Caesar, Matthew; Borisov, Nikita

    2012-01-01

    Many distributed systems are subject to the Sybil attack, where an adversary subverts system operation by emulating behavior of multiple distinct nodes. Most recent work to address this problem leverages social networks to establish trust relationships between users. However, the use of social networks is not appropriate in all systems, as they can be subverted by social engineering techniques, require nodes in a P2P network to maintain and be aware of social network information, and may require overly optimistic assumptions about the fast-mixing nature of social links. This paper explores an alternate approach. We present SybilControl, a novel, decentralized scheme for controlling the extent of Sybil attacks. SybilControl is an admission control mechanism for nodes in a distributed system that requires them to periodically solve computational puzzles. SybilControl consists of a distributed protocol to allow nodes to collectively verify the computational work of other nodes, and mechanisms to prevent the mali...

  8. Dark Atoms and Puzzles of Dark Matter Searches

    CERN Document Server

    Khlopov, M Yu

    2014-01-01

    The nonbaryonic dark matter of the Universe is assumed to consist of new stable forms of matter. Their stability reflects symmetry of micro world and particle candidates for cosmological dark matter are the lightest particles that bear new conserved quantum numbers. Dark matter candidates can appear in the new families of quarks and leptons and the existence of new stable charged leptons and quarks is possible, if they are hidden in elusive "dark atoms". Such possibility, strongly restricted by the constraints on anomalous isotopes of light elements, is not excluded in scenarios that predict stable double charged particles. The excessive -2 charged particles are bound in these scenarios with primordial helium in O-helium "atoms", maintaining specific nuclear-interacting form of the dark matter, which may provide an interesting solution for the puzzles of the direct dark matter searches.

  9. Diagnosing the Cause of Scientific Standstill, Unravelling the Needham Puzzle

    Institute of Scientific and Technical Information of China (English)

    刘迎秋; 刘春江

    2007-01-01

    There are diverse opinions about how to solve the Needham Puzzle. Such opinions or schools of thought can be roughly classified into three theories of a) geographical conditions, b) empirical trial and error, and c) private property rights. Although each school of thought makes sense, they all fail to fully uncover the main reason why, in modern history, China lagged behind western countries in the development of science and technology. In our opinion, the correct solution is to draw on historical experiences, integrate all schools of thought, proceed with an emphasis on the definition and protection of property rights, boost government investment in basic scientific research, strengthen government service functionality, actively develop NGOs, and open more widely to the outside world, with a view of pushing forward China’s scientific and technological innovation and accelerating the pace of China’s modernization.

  10. The B-CP Puzzles in QCD Factorization

    CERN Document Server

    Cheng, Hai-Yang

    2010-01-01

    Within the framework of QCD factorization (QCDF), power corrections due to penguin annihilation can account for theobserved rates of penguin-dominated two-body decays of $B$ mesons and direct CP asymmetries $A_{CP}(K^-\\pi^+)$, $A_{CP}((K^{*-}\\pi^+)$, $A_{CP}((K^-\\rho^0)$ and $A_{CP}((\\pi^+\\pi^-)$. However, the predicted direct CP-violating effects in QCDF for $B^-\\to K^-\\pi^0,K^-\\eta,\\pi^-\\eta$ and $\\bar B^0\\to\\pi^0\\pi^0$ are wrong in signs when confronted with experiment. We consider two different types of power correction effects in order to resolve the CP puzzles and rate deficit problems with penguin-dominated two-body decays of $B$ mesons and color-suppressed tree-dominated $\\pi^0\\pi^0$ and $\\rho^0\\pi^0$ modes: penguin annihilation and soft corrections to the color-suppressed tree amplitude.

  11. A Jigsaw Puzzle Layer Cake of Spatial Data

    Science.gov (United States)

    Ma, Xiaogang; Fox, Peter

    2014-05-01

    The Infrastructure for Spatial Information in Europe (INSPIRE; http://inspire.jrc.ec.europa.eu) is a European Union (EU) directive that aims to provide a legal framework to share environmental spatial data among public sector organizations across Europe and to facilitate public access to data. To meet these goals, INSPIRE's organization is analogous to a layer cake in which each layer is composed of interlocking pieces of a jigsaw puzzle. The metaphor, although mixed, is apt (see additional supporting information in the online version of this article), and as researchers outside the program, we offer our perspective on how INSPIRE may address challenges raised by the variety of data themes and the wide coverage of collaborators.

  12. Ambiguity aversion and household portfolio choice puzzles: Empirical evidence*

    Science.gov (United States)

    Dimmock, Stephen G.; Kouwenberg, Roy; Mitchell, Olivia S.; Peijnenburg, Kim

    2017-01-01

    We test the relation between ambiguity aversion and five household portfolio choice puzzles: nonparticipation in equities, low allocations to equity, home-bias, own-company stock ownership, and portfolio under-diversification. In a representative US household survey, we measure ambiguity preferences using custom-designed questions based on Ellsberg urns. As theory predicts, ambiguity aversion is negatively associated with stock market participation, the fraction of financial assets in stocks, and foreign stock ownership, but it is positively related to own-company stock ownership. Conditional on stock ownership, ambiguity aversion is related to portfolio under-diversification, and during the financial crisis, ambiguity-averse respondents were more likely to sell stocks. PMID:28458446

  13. Ambiguity aversion and household portfolio choice puzzles: Empirical evidence.

    Science.gov (United States)

    Dimmock, Stephen G; Kouwenberg, Roy; Mitchell, Olivia S; Peijnenburg, Kim

    2016-03-01

    We test the relation between ambiguity aversion and five household portfolio choice puzzles: nonparticipation in equities, low allocations to equity, home-bias, own-company stock ownership, and portfolio under-diversification. In a representative US household survey, we measure ambiguity preferences using custom-designed questions based on Ellsberg urns. As theory predicts, ambiguity aversion is negatively associated with stock market participation, the fraction of financial assets in stocks, and foreign stock ownership, but it is positively related to own-company stock ownership. Conditional on stock ownership, ambiguity aversion is related to portfolio under-diversification, and during the financial crisis, ambiguity-averse respondents were more likely to sell stocks.

  14. 200 more puzzling physics problems with hints and solutions

    CERN Document Server

    Gnädig, Péter; Vigh, Máté

    2016-01-01

    Like its predecessor, 200 Puzzling Physics Problems, this book is aimed at strengthening students' grasp of the laws of physics by applying them to situations that are practical, and to problems that yield more easily to intuitive insight than to brute-force methods and complex mathematics. The problems are chosen almost exclusively from classical, non-quantum physics, but are no easier for that. They are intriguingly posed in accessible non-technical language, and require readers to select an appropriate analysis framework and decide which branches of physics are involved. The general level of sophistication needed is that of the exceptional school student, the good undergraduate, or the competent graduate student; some physics professors may find some of the more difficult questions challenging. By contrast, the mathematical demands are relatively minimal, and seldom go beyond elementary calculus. This further book of physics problems is not only instructive and challenging, but also enjoyable.

  15. New analysis concerning the strange quark polarization puzzle

    CERN Document Server

    Leader, Elliot; Stamenov, Dimiter B

    2014-01-01

    The fact that analyses of semi-inclusive deep inelastic scattering suggest that the strange quark polarization $\\Delta s(x) + \\Delta \\bar{s}(x)$ is positive in the measured region of Bjorken x, whereas all analyses of inclusive deep inelastic scattering yield significantly negative values of this quantity, is known as the "strange quark polarization puzzle". We have re-analysed the world data on inclusive deep inelastic scattering, including the COMPASS 2010 proton data on the spin asymmetries, and for the first time, the new extremely precise JLab CLAS data on the proton and deuteron spin structure functions. Despite allowing, in our parametrization, for a possible sign change, our results confirm that the inclusive data yield significantly negative values for the strange quark polarization.

  16. Natural Light Harvesting Systems: Unraveling the quantum puzzles

    CERN Document Server

    Thilagam, A

    2013-01-01

    In natural light harvesting systems, the sequential quantum events of photon absorption by specialized biological antenna complexes, charge separation, exciton formation and energy transfer to localized reaction centers culminates in the conversion of solar to chemical energy. A notable feature in these processes is the exceptionally high efficiencies (> 95 %) at which excitation is transferred from the illuminated protein complex site to the reaction centers. Such high exciton propagation rates within a system of interwoven biomolecular network structures, is yet to be replicated in artificial light harvesting complexes. A clue to unraveling the quantum puzzles of nature may lie in the observation of long lived coherences lasting several picoseconds in the electronic spectra of photosynthetic complexes, even in noisy environmental baths. A number of experimental and theoretical studies have been devoted to unlocking the links between quantum processes and information protocols, in the hope of finding answers...

  17. The Jigsaw Puzzle of Digital Preservation — an Overview

    Directory of Open Access Journals (Sweden)

    Barbara Sierman

    2009-03-01

    Full Text Available Before the 22nd Annual Meeting of the Board of Directors of the Foundation CENL, Zagreb, September 24–27, 2008, the author presented a clear overview of the latest developments in digital preservation in a European context. She dealt with organisational aspects, the digital objects themselves, and the effects of international European collaboration. She calls on European organisations such as the Alliance for Permanent Access to sustain the results of temporary projects like PLANETS and thereby bring the pieces of the digital preservation puzzle together. This paper is being published in preparation of the workshop on Curating Research: e-Merging New Roles and Responsibilities in the European Landscape, which is being co-organised by LIBER on 17 April 2009 at the Koninklijke Bibliotheek in The Hague.

  18. A Possible Resolution of the Strange Quark Polarization Puzzle ?

    CERN Document Server

    Leader, Elliot; Stamenov, Dimiter B

    2011-01-01

    We propose a possible resolution of the strange quark polarization puzzle i.e. of the contradiction between the negative polarized strange quark density obtained from analyses of inclusive DIS data and the positive values obtained from combined analyses of inclusive and semi-inclusive SIDIS data using de Florian et. al. (DSS) fragmentation functions. To this end the results of a new combined NLO QCD analysis of the polarized inclusive and semi-inclusive DIS data, using the Hirai et. al. (HKNS) fragmentation functions, are presented. It is demonstrated that the polarized strange quark density is very sensitive to the kaon fragmentation functions, and if the set of HKNS fragmentation functions is used, the polarized strange quark density from the combined analysis turns out to be negative and well consistent with values obtained from the pure DIS analyses.

  19. Induced Hyperon-Nucleon-Nucleon Interactions and the Hyperon Puzzle

    CERN Document Server

    Wirth, Roland

    2016-01-01

    We present the first ab initio calculations for $p$-shell hypernuclei including hyperon-nucleon-nucleon (YNN) contributions induced by a Similarity Renormalization Group transformation of the initial hyperon-nucleon interaction. The transformation including the YNN terms conserves the spectrum of the Hamiltonian while drastically improving model-space convergence of the Importance-Truncated No-Core Shell Model, allowing a precise extraction of binding and excitation energies. Results using a hyperon-nucleon interaction at leading order in chiral effective field theory for lower- to mid-$p$-shell hypernuclei show a good reproduction of experimental excitation energies while hyperon binding energies are typically overestimated. The induced YNN contributions are strongly repulsive and we show that they are related to a decoupling of the $\\Sigma$ hyperons from the hypernuclear system, i.e., a suppression of the $\\Lambda$-$\\Sigma$ conversion terms in the Hamiltonian. This is linked to the so-called hyperon puzzle ...

  20. A Resolution of the Purchasing Power Parity Puzzle: Imperfect Knowledge and Long Swings

    DEFF Research Database (Denmark)

    Frydman, Roman; Goldberg, Michael D.; Johansen, Søren;

    2009-01-01

    Asset prices undergo long swings that revolve around benchmark levels. In currency markets, fluctuations involve real exchange rates that are highly persistent and that move in near-parallel fashion with nominal rates. The inability to explain these two regularities with one model has been called...... the "purchasing power parity puzzle." In this paper, we trace the puzzle to exchange rate modelers' use of the "Rational Expectations Hypothesis." We show that once imperfect knowledge is recognized, a monetary model is able to account for the puzzle, as well as other salient features of the data, including...

  1. Equity-premium puzzle: evidence from Brazilian data

    Directory of Open Access Journals (Sweden)

    Rubens Penha Cysne

    2006-06-01

    Full Text Available This paper uses 1992:1-2004:2 quarterly data and two different methods (approximation under lognormality and calibration to evaluate the existence of an equity-premium puzzle in Brazil. In contrast with some previous works in the Brazilian literature, I conclude that the model used by Mehra and Prescott (1985, either with additive or recursive preferences, is not able to satisfactorily rationalize the equity premium observed in the Brazilian data. The second contribution of the paper is calling the attention to the fact that the utility function calculated under the discrete-state approximation may not exist if the data (as it is the case with Brazilian time series implies the existence of states in which high negative rates of consumption growth are attained with relatively high probability. This fact is particularly important when the researcher tries to work with high risk-aversion parameters in order to generate high risk premia.Este trabalho usa dados brasileiros do período 1992:1-2004:2 e dois diferentes métodos (aproximação sob a hipótese de lognormalidade e calibração para avaliar a existência de um "equity-premium puzzle" no Brasil. Em contraste com alguns trabalhos prévios da literatura nacional, conclui-se que o modelo usado por Mehra and Prescott (1985, seja com preferências aditivas ou recursivas, não é capaz de gerar o prêmio de risco observado na economia brasileira. A segunda contribuição do trabalho é chamar a atenção para o fato de que a função utilidade calculada sob a hipótese de aproximação discreta do espaço de estados pode não existir se os dados (como é o caso no Brasil implicarem a existência de estados nos quais taxas altamente negativas de crescimento do consumo são alcançadas com probabilidade demasiado elevadas. Este fato é particularmente importante quando se tenta utilizar parâmetros de aversão ao risco altos o suficiente para gerar o prêmio de risco inerente ao caso brasileiro.

  2. Satisfiability Parsimoniously Reduces to the Tantrix(TM) Rotation Puzzle Problem

    CERN Document Server

    Baumeister, Dorothea

    2007-01-01

    Holzer and Holzer (Discrete Applied Mathematics 144(3):345--358, 2004) proved that the Tantrix(TM) rotation puzzle problem is NP-complete. They also showed that for infinite rotation puzzles, this problem becomes undecidable. We study the counting version and the unique version of this problem. We prove that the satisfiability problem parsimoniously reduces to the Tantrix(TM) rotation puzzle problem. In particular, this reduction preserves the uniqueness of the solution, which implies that the unique Tantrix(TM) rotation puzzle problem is as hard as the unique satisfiability problem, and so is DP-complete under polynomial-time randomized reductions, where DP is the second level of the boolean hierarchy over NP.

  3. Fibromyalgia: A Puzzling and Painful Condition | NIH MedlinePlus the Magazine

    Science.gov (United States)

    ... of this page please turn JavaScript on. Feature: Fibromyalgia Fibromyalgia: A Puzzling and Painful Condition Past Issues / Spring ... or internal organs. Wise Choices: Feeling Better with Fibromyalgia Get enough sleep. Getting the right kind of ...

  4. JIGSAW PUZZLE IMPROVE FINE MOTOR ABILITIES OF UPPER EXTREMITIES IN POST-STROKE ISCHEMIC CLIENTS

    Directory of Open Access Journals (Sweden)

    Kusnanto Kusnanto

    2017-06-01

    Full Text Available Introduction: Ischemic stroke is a disease caused by focal cerebral ischemia, where is a decline in blood flow that needed for neuronal metabolism, leading to neurologic deficit include motor deficit such as fine motor skills impairment. Therapy of fine motor skills disorders is to improve motor function, prevent contractures and complications. These study aimed to identify the effect of playing Jigsaw Puzzle on muscle strength, extensive motion, and upper extremity fine motor skills in patients with ischemic stroke at Dr. Moewardi Hospital, Surakarta. Methods: Experimental Quasi pre-posttest one group control. The number of samples were 34 respondents selected using purposive sampling technique. The samples were divided into intervention and control groups. The intervention group was 17 respondents who were given standard treatment hospital and played Jigsaw Puzzle 2 times a day for six days. Control group is one respondent given by hospital standard therapy without given additional Jigsaw Puzzle game. Evaluation of these research is done on the first and seventh day for those groups. Result: The results showed that muscle strength, the range of joint motion and fine motor skills of upper extremities increased (p = 0.001 significantly after being given the Jigsaw Puzzle games. These means playing Jigsaw Puzzle increase muscle strength, the range of joint motion and upper extremity fine motor skill of ischemic stroke patients. Discussion and conclusion: Jigsaw puzzle game administration as additional rehabilitation therapy in upper extremity fine motor to minimize the occurrence of contractures and motor disorders in patients with ischemic stroke. Jigsaw puzzle game therapy capable of creating repetitive motion as a key of neurological rehabilitation in Ischemic Stroke. This study recommends using jigsaw puzzle game as one of intervention in the nursing care of Ischemic Stroke patients.

  5. A Play on Words: Using Cognitive Computing as a Basis for AI Solvers in Word Puzzles

    Science.gov (United States)

    Manzini, Thomas; Ellis, Simon; Hendler, James

    2015-12-01

    In this paper we offer a model, drawing inspiration from human cognition and based upon the pipeline developed for IBM's Watson, which solves clues in a type of word puzzle called syllacrostics. We briefly discuss its situation with respect to the greater field of artificial general intelligence (AGI) and how this process and model might be applied to other types of word puzzles. We present an overview of a system that has been developed to solve syllacrostics.

  6. Monetary Policy Shocks in a Small Open Economy: Assessing the 'Puzzles' of Monetary Policy by SVAR

    OpenAIRE

    Ajluni, Jarir

    2005-01-01

    The paper examines the effects of monetary policy shocks and its puzzles on a small open economy using quarterly Korean data by applying a theoretically motivated Structural VAR, with the objective of introducing empirical evidence that investigates the magnitude and persistence of monetary policy using impulse response function analysis. There is some evidence on the occurrences of monetary policy puzzles confirming previous outcomes in the literature, results suggest that domestic monetary ...

  7. Monetary Policy Shocks in a Small Open Economy: Assessing the 'Puzzles' of Monetary Policy by SVAR

    OpenAIRE

    Ajluni, Jarir

    2005-01-01

    The paper examines the effects of monetary policy shocks and its puzzles on a small open economy using quarterly Korean data by applying a theoretically motivated Structural VAR, with the objective of introducing empirical evidence that investigates the magnitude and persistence of monetary policy using impulse response function analysis. There is some evidence on the occurrences of monetary policy puzzles confirming previous outcomes in the literature, results suggest that domestic monetary ...

  8. Graphene spintronics: puzzling controversies and challenges for spin manipulation

    Science.gov (United States)

    Roche, Stephan; Valenzuela, Sergio O.

    2014-03-01

    This article presents the current puzzling controversy between theory and experimental results concerning the mechanisms leading to spin relaxation in graphene-based materials. On the experimental side, it is surprising that regardless of the quality of the graphene monolayer, which is characterized by the carrier mobility, the typical Hanle precession measurements yield spin diffusion times (τs) in the order of τs ˜ 0.1-1 ns (at low temperatures), which is several orders of magnitude below the theoretical estimates based on the expected low intrinsic spin-orbit coupling in graphene. The results are weakly dependent on whether graphene is deposited onto SiO2 or boron-nitride substrates or is suspended, with the mobility spanning 3 orders of magnitude. On the other hand, extraction form two-terminal magnetoresistance measurements, accounting for contact effects results in τs ˜ 0.1 µs, and corresponding diffusion lengths of about 100 µm up to room temperature. Such discrepancy jeopardizes further progress towards spin manipulation on a lateral graphene two-dimensional platform. After a presentation of basic concepts, we here discuss state-of-the-art literature and the limits of all known approaches to describe spin transport in massless-Dirac fermions, in which the effects of strong local spin-orbit coupling ceases to be accessible with perturbative approaches. We focus on the limits of conventional views of spin transport in graphene and offer novel perspectives for further progress.

  9. Mammary gland stem cells: More puzzles than explanations

    Indian Academy of Sciences (India)

    Suneesh Kaimala; Suneesh Kaimala; Satish Kumar

    2012-06-01

    Mammary gland stem cells (MaSC) have not been identified in spite of extensive research spanning over several decades. This has been primarily due to the complexity of mammary gland structure and its development, cell heterogeneity in the mammary gland and the insufficient knowledge about MaSC markers. At present, Lin–CD29hiCD49fhiCD24+/modSca-1– cells of the mammary gland have been reported to be enriched with MaSCs. We suggest that the inclusion of stem cell markers like Oct4, Sox2, Nanog and the mammary gland differentiation marker BRCA-1 may further narrow down the search for MaSCs. In addition, we have discussed some of the other unresolved puzzles on the mammary gland stem cells, such as their similarities and/or differences with mammary cancer stem cells, use of milk as source of mammary stem cells and the possibility of in vitro differentiation of embryonic stem (ES) cells into functional mammary gland structures in this review. Nevertheless, it is the lack of identity for a MaSC that is curtailing the advances in some of the above and other related areas.

  10. Herschel unveils a puzzling uniformity of distant dusty galaxies

    CERN Document Server

    Elbaz, D; Magnelli, B; Daddi, E; Aussel, H; Altieri, B; Amblard, A; Andreani, P; Arumugam, V; Auld, R; Babbedge, T; Berta, S; Blain, A; Bock, J; Bongiovanni, A; Boselli, A; Buat, V; Burgarella, D; Castro-Rodriguez, N; Cava, A; Cepa, J; Chanial, P; Chary, R -R; Cimatti, A; Clements, D L; Conley, A; Conversi, L; Cooray, A; Dickinson, M; Dominguez, H; Dowell, C D; Dunlop, J S; Dwek, E; Eales, S; Farrah, D; Schreiber, N Forster; Fox, M; Franceschini, A; Gear, W; Genzel, R; Glenn, J; Griffin, M; Gruppioni, C; Halpern, M; Hatziminaoglou, E; Ibar, E; Isaak, K; Ivison, R J; Lagache, G; Le Borgne, D; Le Floc'h, E; Levenson, L; Lu, N; Lutz, D; Madden, S; Maffei, B; Magdis, G; Mainetti, G; Maiolino, R; Marchetti, L; Mortier, A M J; Nguyen, H T; Nordon, R; O'Halloran, B; Okumura, K; Oliver, S J; Omont, A; Page, M J; Panuzzo, P; Papageorgiou, A; Pearson, C P; Fournon, I Perez; Garcıa, A M Perez; Poglitsch, A; Pohlen, M; Popesso, P; Pozzi, F; Rawlings, J I; Rigopoulou, D; Riguccini, L; Rizzo, D; Rodighiero, G; Roseboom, I G; Rowan-Robinson, M; Saintonge, A; Sanchez-Portal, M; Santini, P; Sauvage, M; Schulz, B; Scott, Douglas; Seymour, N; Shao, L; Shupe, D L; Smith, A J; Stevens, J A; Sturm, E; Symeonidis, M; Tacconi, L; Trichas, M; Tugwell, K E; Vaccari, M; Valtchanov, I; Vieira, J; Vigroux, L; Wang, L; Ward, R; Wright, G; Xu, C K; Zemcov, M

    2010-01-01

    The Herschel Space Observatory enables us to accurately measure the bolometric output of starburst galaxies and active galactic nuclei (AGN) by directly sampling the peak of their far-infrared (IR) emission. Here we examine whether the spectral energy distribution (SED) and dust temperature of galaxies have strongly evolved since z~2.5. We use Herschel deep extragalactic surveys from 100 to 500um to compute total IR luminosities in galaxies down to the faintest levels, using PACS and SPIRE in the GOODS-North field (PEP and HerMES key programs). We show that measurements in the SPIRE bands can be used below the statistical confusion limit if information at higher spatial resolution is used to identify isolated galaxies whose flux is not boosted by bright neighbors. Below z~1.5, mid-IR extrapolations are correct for star-forming galaxies with a dispersion of only 40% (0.15dex), therefore similar to z~0 galaxies. This narrow distribution is puzzling when considering the range of physical processes that could hav...

  11. Resolution of the B -> pi pi, pi K puzzles

    CERN Document Server

    Li, Hsiang-nan

    2009-01-01

    We show that there exist uncanceled soft divergences in the k_T factorization for nonfactorizable amplitudes of two-body nonleptonic B meson decays, similar to those identified in hadron-hadron collisions. Viewing the special role of the pion as a q qbar bound state and as a pseudo Nambu-Goldstone boson, we associate a soft factor with it in the perturbative QCD formalism. This soft factor enhances the nonfactorizable color-suppressed tree amplitudes, such that the branching ratios B(pi^0 pi^0) and B(pi^0 rho^0) are increased under the constraint of the B(rho^0 rho^0) data, the difference between the direct CP asymmetries A_{CP}(pi^\\mp K^\\pm) and A_{CP}(pi^0 K^\\pm) is enlarged, and the mixing-induced CP asymmetry S_{pi^0 K_S} is reduced. That is, the known pi pi and pi K puzzles can be resolved simultaneously.

  12. [What type of welfare policy promotes health?: the puzzling interrelation of economic and health inequality].

    Science.gov (United States)

    Hurrelmann, K; Richter, M; Rathmann, K

    2011-06-01

    In all highly developed countries, the overall health status of the population has significantly improved within the past 30 years. The most important reason for this is the increase in economic prosperity. Economic wealth, however, today is much more unequally distributed than it was 3 decades ago. Countries with relatively small disparities in the availability of material resources between socioeconomic groups, such as the Scandinavian countries, have better health outcomes on the population level. Health inequalities, however, have also reached a higher level than 30 years ago. As of today, we do not have convincing explanations for the interrelation of economic and health inequality. This paper gives an overview of existing research on a comparative basis. The research results are ambivalent. They show the puzzling result that the Scandinavian countries with their highly distributive welfare policy manage to achieve the comparatively highest level of economic, but not health, equity. Based on these results, we develop proposals for future research approaches. A central assumption is that in rich societies no longer only material, but more and more immaterial determinants are crucial for the formation of health inequality. The promotion of "salutogenic" self-management capabilities in socially disadvantaged groups is considered to be the central element in effective intervention strategies. © Georg Thieme Verlag KG Stuttgart · New York.

  13. Composite Operator Method Analysis of the Underdoped Cuprates Puzzle

    Directory of Open Access Journals (Sweden)

    Adolfo Avella

    2014-01-01

    Full Text Available The microscopical analysis of the unconventional and puzzling physics of the underdoped cuprates, as carried out lately by means of the composite operator method (COM applied to the 2D Hubbard model, is reviewed and systematized. The 2D Hubbard model has been adopted as it has been considered the minimal model capable of describing the most peculiar features of cuprates held responsible for their anomalous behavior. COM is designed to endorse, since its foundation, the systematic emergence in any SCS of new elementary excitations described by composite operators obeying noncanonical algebras. In this case (underdoped cuprates—2D Hubbard model, the residual interactions—beyond a 2-pole approximation—between the new elementary electronic excitations, dictated by the strong local Coulomb repulsion and well described by the two Hubbard composite operators, have been treated within the noncrossing approximation. Given this recipe and exploiting the few unknowns to enforce the Pauli principle content in the solution, it is possible to qualitatively describe some of the anomalous features of high-Tc cuprate superconductors such as large versus small Fermi surface dichotomy, Fermi surface deconstruction (appearance of Fermi arcs, nodal versus antinodal physics, pseudogap(s, and kinks in the electronic dispersion. The resulting scenario envisages a smooth crossover between an ordinary weakly interacting metal sustaining weak, short-range antiferromagnetic correlations in the overdoped regime to an unconventional poor metal characterized by very strong, long-but-finite-range antiferromagnetic correlations leading to momentum-selective non-Fermi liquid features as well as to the opening of a pseudogap and to the striking differences between the nodal and the antinodal dynamics in the underdoped regime.

  14. Emergence of Life on Earth: A Physicochemical Jigsaw Puzzle.

    Science.gov (United States)

    Spitzer, Jan

    2017-01-01

    We review physicochemical factors and processes that describe how cellular life can emerge from prebiotic chemical matter; they are: (1) prebiotic Earth is a multicomponent and multiphase reservoir of chemical compounds, to which (2) Earth-Moon rotations deliver two kinds of regular cycling energies: diurnal electromagnetic radiation and seawater tides. (3) Emerging colloidal phases cyclically nucleate and agglomerate in seawater and consolidate as geochemical sediments in tidal zones, creating a matrix of microspaces. (4) Some microspaces persist and retain memory from past cycles, and others re-dissolve and re-disperse back into the Earth's chemical reservoir. (5) Proto-metabolites and proto-biopolymers coevolve with and within persisting microspaces, where (6) Macromolecular crowding and other non-covalent molecular forces govern the evolution of hydrophilic, hydrophobic, and charged molecular surfaces. (7) The matrices of microspaces evolve into proto-biofilms of progenotes with rudimentary but evolving replication, transcription, and translation, enclosed in unstable cell envelopes. (8) Stabilization of cell envelopes 'crystallizes' bacteria-like genetics and metabolism with low horizontal gene transfer-life 'as we know it.' These factors and processes constitute the 'working pieces' of the jigsaw puzzle of life's emergence. They extend the concept of progenotes as the first proto-cellular life, connected backward in time to the cycling chemistries of the Earth-Moon planetary system, and forward to the ancient cell cycle of first bacteria-like organisms. Supra-macromolecular models of 'compartments first' are preferred: they facilitate macromolecular crowding-a key abiotic/biotic transition toward living states. Evolutionary models of metabolism or genetics 'first' could not have evolved in unconfined and uncrowded environments because of the diffusional drift to disorder mandated by the second law of thermodynamics.

  15. Hyperon puzzle, hadron-quark crossover and massive neutron stars

    Energy Technology Data Exchange (ETDEWEB)

    Masuda, Kota [The University of Tokyo, Department of Physics, Tokyo (Japan); Nishina Center, RIKEN, Theoretical Research Division, Wako (Japan); Hatsuda, Tetsuo [Nishina Center, RIKEN, Theoretical Research Division, Wako (Japan); The University of Tokyo, Kavli IPMU (WPI), Chiba (Japan); Takatsuka, Tatsuyuki [Nishina Center, RIKEN, Theoretical Research Division, Wako (Japan)

    2016-03-15

    Bulk properties of cold and hot neutron stars are studied on the basis of the hadron-quark crossover picture where a smooth transition from the hadronic phase to the quark phase takes place at finite baryon density. By using a phenomenological equation of state (EOS) ''CRover'', which interpolates the two phases at around 3 times the nuclear matter density (ρ{sub 0}), it is found that the cold NSs with the gravitational mass larger than 2M {sub CircleDot} can be sustained. This is in sharp contrast to the case of the first-order hadron-quark transition. The radii of the cold NSs with the CRover EOS are in the narrow range (12.5 ± 0.5) km which is insensitive to the NS masses. Due to the stiffening of the EOS induced by the hadron-quark crossover, the central density of the NSs is at most 4 ρ{sub 0} and the hyperon-mixing barely occurs inside the NS core. This constitutes a solution of the long-standing hyperon puzzle. The effect of color superconductivity (CSC) on the NS structures is also examined with the hadron-quark crossover. For the typical strength of the diquark attraction, a slight softening of the EOS due to two-flavor CSC (2SC) takes place and the maximum mass is reduced by about 0.2M {sub CircleDot}. The CRover EOS is generalized to the supernova matter at finite temperature to describe the hot NSs at birth. The hadron-quark crossover is found to decrease the central temperature of the hot NSs under isentropic condition. The gravitational energy release and the spin-up rate during the contraction from the hot NS to the cold NS are also estimated. (orig.)

  16. Desiccation tolerance of Sphagnum revisited: a puzzle resolved.

    Science.gov (United States)

    Hájek, T; Vicherová, E

    2014-07-01

    As ecosystem engineers, Sphagnum mosses control their surroundings through water retention, acidification and peat accumulation. Because water retention avoids desiccation, sphagna are generally intolerant to drought; however, the literature on Sphagnum desiccation tolerance (DT) provides puzzling results, indicating the inducible nature of their DT. To test this, various Sphagnum species and other mesic bryophytes were hardened to drought by (i) slow drying; (ii) ABA application and (iii) chilling or frost. DT tolerance was assessed as recovery of chlorophyll fluorescence parameters after severe desiccation. We monitored the seasonal course of DT in bog bryophytes. Under laboratory conditions, following initial de-hardening, untreated Sphagnum shoots lacked DT; however, DT was induced by all hardening treatments except chilling, notably by slow drying, and in Sphagnum species of the section Cuspidata. In the field, sphagna in hollows and lawns developed DT several times during the growing season, responding to reduced precipitation and a lowered water table. Hummock and aquatic species developed DT only in late autumn, probably as a response to frost. Sphagnum protonemata failed to develop DT; hence, desiccation may limit Sphagnum establishment in drier habitats with suitable substrate chemistry. Desiccation avoiders among sphagna form compact hummocks or live submerged; thus, they do not develop DT in the field, lacking the initial desiccation experience, which is frequent in hollow and lawn habitats. We confirmed the morpho-physiological trade-off: in contrast to typical hollow sphagna, hummock species invest more resources in water retention (desiccation avoidance), while they have a lower ability to develop physiological DT. © 2013 German Botanical Society and The Royal Botanical Society of the Netherlands.

  17. What cognitive strategies do orangutans (Pongo pygmaeus) use to solve a trial-unique puzzle-tube task incorporating multiple obstacles?

    Science.gov (United States)

    Tecwyn, Emma C; Thorpe, Susannah K S; Chappell, Jackie

    2012-01-01

    Apparently sophisticated behaviour during problem-solving is often the product of simple underlying mechanisms, such as associative learning or the use of procedural rules. These and other more parsimonious explanations need to be eliminated before higher-level cognitive processes such as causal reasoning or planning can be inferred. We presented three Bornean orangutans with 64 trial-unique configurations of a puzzle-tube to investigate whether they were able to consider multiple obstacles in two alternative paths, and subsequently choose the correct direction in which to move a reward in order to retrieve it. We were particularly interested in how subjects attempted to solve the task, namely which behavioural strategies they could have been using, as this is how we may begin to elucidate the cognitive mechanisms underpinning their choices. To explore this, we simulated performance outcomes across the 64 trials for various procedural rules and rule combinations that subjects may have been using based on the configuration of different obstacles. Two of the three subjects solved the task, suggesting that they were able to consider at least some of the obstacles in the puzzle-tube before executing action to retrieve the reward. This is impressive compared with the past performances of great apes on similar, arguably less complex tasks. Successful subjects may have been using a heuristic rule combination based on what they deemed to be the most relevant cue (the configuration of the puzzle-tube ends), which may be a cognitively economical strategy.

  18. Physics and financial economics (1776-2014): puzzles, Ising and agent-based models.

    Science.gov (United States)

    Sornette, Didier

    2014-06-01

    This short review presents a selected history of the mutual fertilization between physics and economics--from Isaac Newton and Adam Smith to the present. The fundamentally different perspectives embraced in theories developed in financial economics compared with physics are dissected with the examples of the volatility smile and of the excess volatility puzzle. The role of the Ising model of phase transitions to model social and financial systems is reviewed, with the concepts of random utilities and the logit model as the analog of the Boltzmann factor in statistical physics. Recent extensions in terms of quantum decision theory are also covered. A wealth of models are discussed briefly that build on the Ising model and generalize it to account for the many stylized facts of financial markets. A summary of the relevance of the Ising model and its extensions is provided to account for financial bubbles and crashes. The review would be incomplete if it did not cover the dynamical field of agent-based models (ABMs), also known as computational economic models, of which the Ising-type models are just special ABM implementations. We formulate the 'Emerging Intelligence Market Hypothesis' to reconcile the pervasive presence of 'noise traders' with the near efficiency of financial markets. Finally, we note that evolutionary biology, more than physics, is now playing a growing role to inspire models of financial markets.

  19. From polarisation to practice: puzzles and insights on integrated approaches from public health professionals.

    Science.gov (United States)

    Buffardi, Anne L

    2014-01-01

    Much of the debate in the global health literature about vertical and horizontal programmatic approaches, between narrowly targeted interventions and those providing broader system-wide support, has taken place at the global level. Based on a comparative case study of international donors in the health sector in Peru that varied in their vertical-horizontal orientation, this article examines the extent to which health care practitioners and national policy-makers perceive and attempt to reconcile the tension between these approaches. Informants readily identified advantages and disadvantages of both approaches, but did not perceive a marked vertical-horizontal division, suggesting that tensions appear to be less pronounced in practice than academic debates suggest. A clear consensus did not emerge, and although more people spoke of a mixed approached, they too puzzled over how best to balance trade-offs. In practice, there were examples of more integrated approaches, targeted aspects of horizontal programmes and system-strengthening elements of vertical programmes; however, they were not explicitly identified as such. Practitioner perspectives reinforced the diverse and dynamic nature of disease, both epidemics and country profiles, and suggest that focusing on periods of transition and points of integration may be a fruitful path forward.

  20. The placebo puzzle: examining the discordant space between biomedical science and illness/healing.

    Science.gov (United States)

    Pohlman, Shawn; Cibulka, Nancy J; Palmer, Janice L; Lorenz, Rebecca A; SmithBattle, Lee

    2013-03-01

    The placebo response presents an enigma to biomedical science: how can 'inert' or 'sham' procedures reduce symptoms and produce physiological changes that are comparable to prescribed treatments? In this study, we examine this puzzle by explicating the discordant space between the prevailing biomedical paradigm, which focuses on a technical understanding of diagnosis and treatment, and a broader understanding of illness and healing as relational and embodied. Although biomedical achievements are impressive, the knowledge resulting from this paradigm is limited by its ontological and epistemological assumptions. When the body and world are objectified, illness meanings, therapeutic relationships, and healing practices are dismissed or distorted. In spite of a robust critique of the tenets of biomedicine for guiding practice, the biomedical paradigm retains a tenacious hold on evidence-based medicine and nursing, downplaying our clinical understanding of the sentient body, patients' life-worlds, and illness and healing. In reality, skilled nurses rely on multiple forms of knowledge in providing high-quality care to particular patients. Clinically wise nurses integrate their experience and knowledge of patients' priorities, fears, and illness trajectories along with biomedical findings to make astute judgments and promote health and healing. © 2012 Blackwell Publishing Ltd.

  1. Physics and financial economics (1776-2014): puzzles, Ising and agent-based models

    Science.gov (United States)

    Sornette, Didier

    2014-06-01

    This short review presents a selected history of the mutual fertilization between physics and economics—from Isaac Newton and Adam Smith to the present. The fundamentally different perspectives embraced in theories developed in financial economics compared with physics are dissected with the examples of the volatility smile and of the excess volatility puzzle. The role of the Ising model of phase transitions to model social and financial systems is reviewed, with the concepts of random utilities and the logit model as the analog of the Boltzmann factor in statistical physics. Recent extensions in terms of quantum decision theory are also covered. A wealth of models are discussed briefly that build on the Ising model and generalize it to account for the many stylized facts of financial markets. A summary of the relevance of the Ising model and its extensions is provided to account for financial bubbles and crashes. The review would be incomplete if it did not cover the dynamical field of agent-based models (ABMs), also known as computational economic models, of which the Ising-type models are just special ABM implementations. We formulate the ‘Emerging Intelligence Market Hypothesis’ to reconcile the pervasive presence of ‘noise traders’ with the near efficiency of financial markets. Finally, we note that evolutionary biology, more than physics, is now playing a growing role to inspire models of financial markets.

  2. Genetic variation in the vulnerable and endemic Monkey Puzzle tree, detected using RAPDs.

    Science.gov (United States)

    Bekessy, Sarah A; Allnutt, T R; Premoli, A C; Lara, A; Ennos, R A; Burgman, M A; Cortes, M; Newton, A C

    2002-04-01

    Araucaria araucana (Monkey Puzzle), a southern South American tree species of exceptional cultural and economic importance, is of conservation concern owing to extensive historical clearance and current human pressures. Random amplified polymorphic DNA (RAPD) markers were used to characterise genetic heterogeneity within and among 13 populations of this species from throughout its natural range. Extensive genetic variability was detected and partitioned by analysis of molecular variance, with the majority of variation existing within populations (87.2%), but significant differentiation was recorded among populations (12.8%). Estimates of Shannon's genetic diversity and percent polymorphism were relatively high for all populations and provide no evidence for a major reduction in genetic diversity from historical events, such as glaciation. All pairwise genetic distance values derived from analysis of molecular variance (Phi(ST)) were significant when individual pairs of populations were compared. Although populations are geographically divided into Chilean Coastal, Chilean Andes and Argentinean regions, this grouping explained only 1.77% of the total variation. Within Andean groups there was evidence of a trend of genetic distance with increasing latitude, and clustering of populations across the Andes, suggesting postglacial migration routes from multiple refugia. Implications of these results for the conservation and use of the genetic resource of this species are discussed.

  3. A puzzling aspect of the effect of advance notice on unemployment

    DEFF Research Database (Denmark)

    Addision, John; Blackburn, McKinley L.

    1995-01-01

    Displaced male workers with generous periods of advance notice tend to move directly into reemployment faster than their non-notified counterparts but once unemployed tend to escape from unemployment much more slowly. We examine three potential explanations for this puzzle associated with unemplo......Displaced male workers with generous periods of advance notice tend to move directly into reemployment faster than their non-notified counterparts but once unemployed tend to escape from unemployment much more slowly. We examine three potential explanations for this puzzle associated...... with unemployment insurance, the endogeneity of notice, and differential search intensity. Of these alternatives, the evidence suggests that it is the additional but less productive search time during the notice interval that creates the appearance of a puzzle....

  4. Cryptographic Puzzles and Game Theory against DoS and DDoS attacks in Networks

    DEFF Research Database (Denmark)

    Mikalas, Antonis; Komninos, Nikos; Prasad, Neeli R.

    2008-01-01

    In this chapter, we present techniques to defeat Denial of Service (DoS) and Distributed Denial of Service (DDoS) attacks. In the _rst part, we describe client puzzle techniques that are based on the idea of computationally exhausting a malicious user when he attempts to launch an attack. In the ......In this chapter, we present techniques to defeat Denial of Service (DoS) and Distributed Denial of Service (DDoS) attacks. In the _rst part, we describe client puzzle techniques that are based on the idea of computationally exhausting a malicious user when he attempts to launch an attack....... In the second part we are introducing some basic principles of game theory and we discuss how game theoretical frameworks can protect computer networks. Finally, we show techniques that combine client puzzles with game theory in order to provide DoS and DDoS resilience....

  5. Puzzle Imaging: Using Large-Scale Dimensionality Reduction Algorithms for Localization.

    Directory of Open Access Journals (Sweden)

    Joshua I Glaser

    Full Text Available Current high-resolution imaging techniques require an intact sample that preserves spatial relationships. We here present a novel approach, "puzzle imaging," that allows imaging a spatially scrambled sample. This technique takes many spatially disordered samples, and then pieces them back together using local properties embedded within the sample. We show that puzzle imaging can efficiently produce high-resolution images using dimensionality reduction algorithms. We demonstrate the theoretical capabilities of puzzle imaging in three biological scenarios, showing that (1 relatively precise 3-dimensional brain imaging is possible; (2 the physical structure of a neural network can often be recovered based only on the neural connectivity matrix; and (3 a chemical map could be reproduced using bacteria with chemosensitive DNA and conjugative transfer. The ability to reconstruct scrambled images promises to enable imaging based on DNA sequencing of homogenized tissue samples.

  6. Does The Price Puzzle Exist in Colombia? Empirical Evidence and Policy Implications

    Directory of Open Access Journals (Sweden)

    Blen Solomon

    2006-04-01

    Full Text Available The price puzzle has been the focus of many studies, however, most of these studies have focused on developed economies and especially on the U.S. Owing to this tendency; we do not know if there is existence of a price puzzle in developing economies. This is an important topic of research as it facilitates the understanding on the different channels of monetary policy. It also helps our understanding regarding monetary policy effectiveness and in the context of the Colombian economy, this is a main issue as the basic long-term target of Colombia’s monetary policy is price stability. This study investigates the existence of the price puzzle for the period 1980:5-2003:12 in Colombia by using Vector Error Correction Model (VECM. Since the sample period of study is not characterized with a uniform monetary policy regime, following Balke and Emery (1994 we divide our sample period according to existent structural breaks. We test for the price puzzle by dividing our sample into pre-1991 period (before inflation targeting started and during inflation targeting period. We employ impulse response functions as our main tolos to investigate the price puzzle. The impulse response functions show that during both the pre-1991 and post 1991 periods, prices don’t rise in response to positive shocks in short term interest rates. Therefore we conclude that Colombia does not exhibit the price puzzle. In fact, during both periods as well as the whole sample period, prices are not responsive to short-term interest rate shocks. The unresponsiveness of prices to positive interest rate shocks is not expected since we would anticipate prices to decrease due to a positive interest rate shock

  7. RNA-Puzzles Round III: 3D RNA structure prediction of five riboswitches and one ribozyme.

    Science.gov (United States)

    Miao, Zhichao; Adamiak, Ryszard W; Antczak, Maciej; Batey, Robert T; Becka, Alexander J; Biesiada, Marcin; Boniecki, Michał J; Bujnicki, Janusz; Chen, Shi-Jie; Cheng, Clarence Yu; Chou, Fang-Chieh; Ferré-D'Amaré, Adrian R; Das, Rhiju; Dawson, Wayne K; Feng, Ding; Dokholyan, Nikolay V; Dunin-Horkawicz, Stanisław; Geniesse, Caleb; Kappel, Kalli; Kladwang, Wipapat; Krokhotin, Andrey; Łach, Grzegorz E; Major, François; Mann, Thomas H; Magnus, Marcin; Pachulska-Wieczorek, Katarzyna; Patel, Dinshaw J; Piccirilli, Joseph A; Popenda, Mariusz; Purzycka, Katarzyna J; Ren, Aiming; Rice, Greggory M; Santalucia, John; Sarzynska, Joanna; Szachniuk, Marta; Tandon, Arpit; Trausch, Jeremiah J; Tian, Siqi; Wang, Jian; Weeks, Kevin M; Williams, Benfeard; Xiao, Yi; Xu, Xiaojun; Zhang, Dong; Zok, Tomasz; Westhof, Eric

    2017-01-30

    RNA-Puzzles is a collective experiment in blind 3D RNA structure prediction. We report here a third round of RNA-Puzzles. Five puzzles, 4, 8, 12, 13, 14, all structures of riboswitch aptamers and puzzle 7, a ribozyme structure, are included in this round of the experiment. The riboswitch structures include biological binding sites for small molecules (S-adenosyl methionine, cyclic diadenosine monophosphate, 5-amino 4-imidazole carboxamide riboside 5'-triphosphate, glutamine) and proteins (YbxF) and one set describes large conformational changes between ligand-free and ligand-bound states; the Varkud satellite ribozyme is the most recently solved structure of a known large ribozyme. All the puzzles have established biological functions and require structural understanding to appreciate their molecular mechanisms. Through the use of fast-track experimental data, including multidimensional chemical mapping, and accurate prediction of RNA secondary structure, a large portion of the contacts in 3D have been predicted correctly leading to similar topologies for the top ranking predictions. Template-based and homology-derived predictions could predict structures to particularly high accuracies. However, achieving biological insights from de novo prediction of RNA 3D structures still depends on the size and complexity of the RNA. Blind computational predictions of RNA structures already appear to provide useful structural information in many cases. Similar to the previous RNA-Puzzles Round II experiment, the prediction of non-Watson-Crick interactions and the observed high atomic clash scores reveal notable need for algorithm of improvement. All prediction models and assessment results are available at http://ahsoka.u-strasbg.fr/rnapuzzles/.

  8. Using the Tower of Hanoi puzzle to infuse your mathematics classroom with computer science concepts

    Science.gov (United States)

    Marzocchi, Alison S.

    2016-07-01

    This article suggests that logic puzzles, such as the well-known Tower of Hanoi puzzle, can be used to introduce computer science concepts to mathematics students of all ages. Mathematics teachers introduce their students to computer science concepts that are enacted spontaneously and subconsciously throughout the solution to the Tower of Hanoi puzzle. These concepts include, but are not limited to, conditionals, iteration, and recursion. Lessons, such as the one proposed in this article, are easily implementable in mathematics classrooms and extracurricular programmes as they are good candidates for 'drop in' lessons that do not need to fit into any particular place in the typical curriculum sequence. As an example for readers, the author describes how she used the puzzle in her own Number Sense and Logic course during the federally funded Upward Bound Math/Science summer programme for college-intending low-income high school students. The article explains each computer science term with real-life and mathematical examples, applies each term to the Tower of Hanoi puzzle solution, and describes how students connected the terms to their own solutions of the puzzle. It is timely and important to expose mathematics students to computer science concepts. Given the rate at which technology is currently advancing, and our increased dependence on technology in our daily lives, it has become more important than ever for children to be exposed to computer science. Yet, despite the importance of exposing today's children to computer science, many children are not given adequate opportunity to learn computer science in schools. In the United States, for example, most students finish high school without ever taking a computing course. Mathematics lessons, such as the one described in this article, can help to make computer science more accessible to students who may have otherwise had little opportunity to be introduced to these increasingly important concepts.

  9. Heavy quark dynamics in the QGP: Towards a solution of the RAA and ν2 puzzle

    Directory of Open Access Journals (Sweden)

    Scardina F.

    2016-01-01

    Full Text Available The two key observables related to heavy quarks that have been measured in experiments are the nuclear suppression factor RAA and the elliptic flow ν2. The simultaneous reproduction of these two observables is a puzzle which have challenged all the existing models. We discuss two ingredients responsible for addressing a large part of such a puzzle: the temperature dependence of the energy loss and the full solution of the Boltzmann collision integral for the scattering between the heavy quarks and the particle of the bulk.

  10. Utility of Self-Made Crossword Puzzles as an Active Learning Method to Study Biochemistry in Undergraduate Education

    Science.gov (United States)

    Coticone, Sulekha Rao

    2013-01-01

    To incorporate an active learning component in a one-semester biochemistry course, students were asked to create crossword puzzles using key concepts. Student observations on the use of self-made crossword puzzles as an active-learning instructional tool were collected using a 5-point Likert survey at the end of the semester. A majority of the…

  11. The puzzling Hg family revisited: a comprehensive study based on density functional theory

    Directory of Open Access Journals (Sweden)

    C. Ambrosch-Draxl

    2006-09-01

    Full Text Available   We review theoretical investigations of high-temperature superconductors which have been performed by density functional theory. The main subject of our study is the Hg-based family of the superconducting cuprates, which demonstrates unusual and still puzzling properties. We show that the first-principles approach is able to describe the effects of chemical doping and pressure on the structural properties, the band structure, the ion charges, and the chemical bonds. We report on the origin of the optimal doping and present results on the inhomegeneity of the charge distribution and the concomitant splitting of the electronic bands and their contributions to the density of states. Due to their individual energy dependence, the role of the intrinsic inhomogeneities for superconductivity strongly depends on the energy and character of the quasiparticle mediating the Cooper pairing. The evolution of the electric field gradients with doping is analyzed and compared to nuclear resonance experiments. The calculated results can explain the origin of doping-induced effects observed either by local or macroscopic experimental probes. From a systematic study of the density of states by varying the doping concentration as well as applying pressure up to 15 GPa, and comparison with the measured critical temperatures, the coupling constant of the quasiparticle has been estimated to be of the order of one. Moreover, we show how density functional theory allows for the calculation of vibrational properties and phonon Raman scattering in the high-Tc cuprates. All results are quantitatively compared to experiment, and have revealed very good agreement.

  12. Random Tree-Puzzle leads to the Yule-Harding distribution.

    Science.gov (United States)

    Vinh, Le Sy; Fuehrer, Andrea; von Haeseler, Arndt

    2011-02-01

    Approaches to reconstruct phylogenies abound and are widely used in the study of molecular evolution. Partially through extensive simulations, we are beginning to understand the potential pitfalls as well as the advantages of different methods. However, little work has been done on possible biases introduced by the methods if the input data are random and do not carry any phylogenetic signal. Although Tree-Puzzle (Strimmer K, von Haeseler A. 1996. Quartet puzzling: a quartet maximum-likelihood method for reconstructing tree topologies. Mol Biol Evol. 13:964-969; Schmidt HA, Strimmer K, Vingron M, von Haeseler A. 2002. Tree-Puzzle: maximum likelihood phylogenetic analysis using quartets and parallel computing. Bioinformatics 18:502-504) has become common in phylogenetics, the resulting distribution of labeled unrooted bifurcating trees when data do not carry any phylogenetic signal has not been investigated. Our note shows that the distribution converges to the well-known Yule-Harding distribution. However, the bias of the Yule-Harding distribution will be diminished by a tiny amount of phylogenetic information. maximum likelihood, phylogenetic reconstruction, Tree-Puzzle, tree distribution, Yule-Harding distribution.

  13. On the Puzzle of Long and Short Gamma-Ray Bursts

    CERN Document Server

    Shao, Lang; Dai, Zi-Gao; Jin, Zhi-Ping; Yan, Jing-Zhi; Wei, Da-Ming

    2014-01-01

    In this paper we give a brief review of our recent studies on the long and short gamma-ray bursts (GRBs) detected Swift, in an effort to understand the puzzle of classifying GRBs. We consider that it is still an appealing conjecture that both long and short GRBs are drawn from the same parent sample by observational biases.

  14. The Quark Puzzle: A Novel Approach to Visualizing the Color Symmetries of Quarks

    Science.gov (United States)

    Gettrust, Eric

    2010-01-01

    This paper describes a simple hands-on and visual-method designed to introduce physics students of many age groups to the topic of quarks and their role in forming composite particles (baryons and mesons). A set of puzzle pieces representing individual quarks that fit together in ways consistent with known restrictions of flavor, color, and charge…

  15. The Quark Puzzle: A Novel Approach to Visualizing the Color Symmetries of Quarks

    Science.gov (United States)

    Gettrust, Eric

    2010-01-01

    This paper describes a simple hands-on and visual-method designed to introduce physics students of many age groups to the topic of quarks and their role in forming composite particles (baryons and mesons). A set of puzzle pieces representing individual quarks that fit together in ways consistent with known restrictions of flavor, color, and charge…

  16. Enhancing the Understanding of Government and Nonprofit Accounting with THE PUZZLE GAME: A Pilot Study

    Science.gov (United States)

    Elson, Raymond J.; Ostapski, S. Andrew; O'Callaghan, Susanne; Walker, John P.

    2012-01-01

    Nontraditional teaching aids such as crossword puzzles have been successfully used in the classroom to enhance student learning. Government and nonprofit accounting is a confusing course for students since it has strange terminologies and contradicts the accounting concepts learned in other courses. As such, it is an ideal course for a…

  17. High-mass twins & resolution of the reconfinement, masquerade and hyperon puzzles of compact star interiors

    Energy Technology Data Exchange (ETDEWEB)

    Blaschke, David [Bogoliubov Laboratory for Theoretical Physics, JINR Dubna, 141980 Dubna (Russian Federation); Instytut Fizyki Teoretycznej, Uniwersytet Wroclawski, 50-204 Wroclaw (Poland); Alvarez-Castillo, David E. [Bogoliubov Laboratory for Theoretical Physics, JINR Dubna, 141980 Dubna (Russian Federation); Instituto de Física, Universidad Autónoma de San Luis Potosí, San Luis Potosí, México (Mexico)

    2016-01-22

    We aim at contributing to the resolution of three of the fundamental puzzles related to the still unsolved problem of the structure of the dense core of compact stars (CS): (i) the hyperon puzzle: how to reconcile pulsar masses of 2 M{sub ⊙} with the hyperon softening of the equation of state (EoS); (ii) the masquerade problem: modern EoS for cold, high density hadronic and quark matter are almost identical; and (iii) the reconfinement puzzle: what to do when after a deconfinement transition the hadronic EoS becomes favorable again? We show that taking into account the compositeness of baryons (by excluded volume and/or quark Pauli blocking) on the hadronic side and confining and stiffening effects on the quark matter side results in an early phase transition to quark matter with sufficient stiffening at high densities which removes all three present-day puzzles of CS interiors. Moreover, in this new class of EoS for hybrid CS falls the interesting case of a strong first order phase transition which results in the observable high mass twin star phenomenon, an astrophysical observation of a critical endpoint in the QCD phase diagram.

  18. Precedents, Patterns and Puzzles: Feminist Reflections on the First Women Lawyers

    Directory of Open Access Journals (Sweden)

    Mary Jane Mossman

    2016-10-01

    Full Text Available This paper initially examines the historical precedents established by some of the first women who entered the “gentleman’s profession” of law in different jurisdictions, as well as the biographical patterns that shaped some women’s ambitions to enter the legal professions. The paper then uses feminist methods and theories to interpret “puzzles that remain unsolved” about early women lawyers, focusing especially on two issues. One puzzle is the repeated claims on the part of many of these early women lawyers that they were “lawyers”, and not “women lawyers”, even as they experienced exclusionary practices and discrimination on the part of male lawyers and judges—a puzzle that suggests how professional culture required women lawyers to conform to existing patterns in order to succeed. A second puzzle relates to the public voices of early women lawyers, which tended to suppress disappointments, difficulties and discriminatory practices. In this context, feminist theories suggest a need to be attentive to the “silences” in women’s stories, including the stories of the lives of early women lawyers. Moreover, these insights may have continuing relevance for contemporary women lawyers because it is at least arguable that, while there have been changes in women’s experiences, there has been very little transformation in their work status in relation to men.

  19. High-mass twins & resolution of the reconfinement, masquerade and hyperon puzzles of compact star interiors

    CERN Document Server

    Blaschke, David

    2016-01-01

    We aim at contributing to the resolution of three of the fundamental puzzles related to the still unsolved problem of the structure of the dense core of compact stars (CS): (i) the hyperon puzzle: how to reconcile pulsar masses of $2\\,$M$_\\odot$ with the hyperon softening of the equation of state (EoS); (ii) the masquerade problem: modern EoS for cold, high density hadronic and quark matter are almost identical; and (iii) the reconfinement puzzle: what to do when after a deconfinement transition the hadronic EoS becomes favorable again? We show that taking into account the compositeness of baryons (by excluded volume and/or quark Pauli blocking) on the hadronic side and confining and stiffening effects on the quark matter side results in an early phase transition to quark matter with sufficient stiffening at high densities which removes all three present-day puzzles of CS interiors. Moreover, in this new class of EoS for hybrid CS falls the interesting case of a strong first order phase transition which resul...

  20. Instructional Media Production for Early Childhood Education: A. B. C. Jig-Saw Puzzle, a Model

    Science.gov (United States)

    Yusuf, Mudashiru Olalere; Olanrewaju, Olatayo Solomon; Soetan, Aderonke K.

    2015-01-01

    In this paper, a. b. c. jig-saw puzzle was produced for early childhood education using local materials. This study was a production based type of research, to serve as a supplemental or total learning resource. Its production followed four phases of development referred to as information, design, production and evaluation. The storyboard cards,…

  1. The Puzzle of Simultaneous Anti-Dumping and Anti-Subsidy Measures

    DEFF Research Database (Denmark)

    Nielsen, Jørgen Ulff-Møller; Hansen, Jørgen Drud

    these puzzles in a theoretical analysis based on a duopoly model for a horizontally differentiated product. We argue that the procedures of two investigations leading to a two-component duty may be rational because it provides an incentive for the offending country and companies to terminate their ‘unfair...

  2. Understanding the proton radius puzzle: Nuclear structure effects in light muonic atoms

    CERN Document Server

    Ji, Chen; Dinur, Nir Nevo; Bacca, Sonia; Barnea, Nir

    2015-01-01

    We present calculations of nuclear structure effects to the Lamb shift in light muonic atoms. We adopt a modern ab-initio approach by combining state-of-the-art nuclear potentials with the hyperspherical harmonics method. Our calculations are instrumental to the determination of nuclear charge radii in the Lamb shift measurements, which will shed light on the proton radius puzzle.

  3. New data and an old puzzle : the negative association between schizophrenia and rheumatoid arthritis

    NARCIS (Netherlands)

    Lee, S Hong; Byrne, Enda M; Hultman, Christina M; Kähler, Anna; Vinkhuyzen, Anna Ae; Ripke, Stephan; Andreassen, Ole A; Frisell, Thomas; Gusev, Alexander; Hu, Xinli; Karlsson, Robert; Mantzioris, Vasilis X; McGrath, John J; Mehta, Divya; Stahl, Eli A; Zhao, Qiongyi; Kendler, Kenneth S; Sullivan, Patrick F; Price, Alkes L; O'Donovan, Michael; Okada, Yukinori; Mowry, Bryan J; Raychaudhuri, Soumya; Wray, Naomi R; Byerley, William; Cahn, Wiepke; Cantor, Rita M; Cichon, Sven; Cormican, Paul; Curtis, David; Djurovic, Srdjan; Escott-Price, Valentina; Gejman, Pablo V; Georgieva, Lyudmila; Giegling, Ina; Hansen, Thomas F; Ingason, Andrés; Kim, Yunjung; Konte, Bettina; Lee, Phil H; McIntosh, Andrew; McQuillin, Andrew; Morris, Derek W; Nöthen, Markus M; O'Dushlaine, Colm; Olincy, Ann; Olsen, Line; Pato, Carlos N; Pato, Michele T; Pickard, Benjamin S; Posthuma, Danielle; Rasmussen, Henrik B; Rietschel, Marcella; Rujescu, Dan; Schulze, Thomas G; Silverman, Jeremy M; Thirumalai, Srinivasa; Werge, Thomas; Agartz, Ingrid; Amin, Farooq; Azevedo, Maria H; Bass, Nicholas; Black, Donald W; Blackwood, Douglas H R; Bruggeman, Richard; Buccola, Nancy G; Choudhury, Khalid; Cloninger, Robert C; Corvin, Aiden; Craddock, Nicholas; Daly, Mark J; Datta, Susmita; Donohoe, Gary J; Duan, Jubao; Dudbridge, Frank; Fanous, Ayman; Freedman, Robert; Freimer, Nelson B; Friedl, Marion; Gill, Michael; Gurling, Hugh; De Haan, Lieuwe; Hamshere, Marian L; Hartmann, Annette M; Holmans, Peter A; Kahn, René S; Keller, Matthew C; Kenny, Elaine; Kirov, George K; Krabbendam, Lydia; Krasucki, Robert; Lawrence, Jacob; Lencz, Todd; Levinson, Douglas F; Lieberman, Jeffrey A; Lin, Dan-Yu; Linszen, Don H; Magnusson, Patrik Ke; Maier, Wolfgang; Malhotra, Anil K; Mattheisen, Manuel; Mattingsdal, Morten; McCarroll, Steven A; Medeiros, Helena; Melle, Ingrid; Milanova, Vihra; Myin-Germeys, Inez; Neale, Benjamin M; Ophoff, Roel A; Owen, Michael J; Pimm, Jonathan; Purcell, Shaun M; Puri, Vinay; Quested, Digby J; Rossin, Lizzy; Ruderfer, Douglas; Sanders, Alan R; Shi, Jianxin; Sklar, Pamela; St Clair, David; Scott Stroup, T; Van Os, Jim; Visscher, Peter M; Wiersma, Durk; Zammit, Stanley; Louis Bridges, S; Choi, Hyon K; Coenen, Marieke Jh; de Vries, Niek; Dieud, Philippe; Greenberg, Jeffrey D; Huizinga, Tom Wj; Padyukov, Leonid; Siminovitch, Katherine A; Tak, Paul P; Worthington, Jane; De Jager, Philip L; Denny, Joshua C; Gregersen, Peter K; Klareskog, Lars; Mariette, Xavier; Plenge, Robert M; van Laar, Mart; van Riel, Piet

    2015-01-01

    BACKGROUND: A long-standing epidemiological puzzle is the reduced rate of rheumatoid arthritis (RA) in those with schizophrenia (SZ) and vice versa. Traditional epidemiological approaches to determine if this negative association is underpinned by genetic factors would test for reduced rates of one

  4. Booklists for the Teaching of Mathematics in Schools: Puzzles, Problems, Games and Mathematical Recreations (Ref: PGR).

    Science.gov (United States)

    Mathematical Association, Leicester (England).

    Presented is a listing of books recommended by the Mathematical Association of the United Kingdom dealing with Puzzles, Problems, Games, and Mathematical Recreations. The following information on each book is provided: author; title; publisher; cost to the nearest pound; categories of use; and a code that indicates if the book in question is out…

  5. (Mis)perception of Sleep in Insomnia: A Puzzle and a Resolution

    Science.gov (United States)

    Harvey, Allison G.; Tang, Nicole K. Y.

    2012-01-01

    Insomnia is prevalent, causing severe distress and impairment. This review focuses on illuminating the puzzling finding that many insomnia patients misperceive their sleep. They overestimate their sleep onset latency (SOL) and underestimate their total sleep time (TST), relative to objective measures. This tendency is ubiquitous (although not…

  6. Games Puzzle Hijaiyah Elektronik Interaktif Berbasis Mikrokontroler DT-AVR Maxiduino

    Directory of Open Access Journals (Sweden)

    Agus Mulyana

    2015-05-01

    Full Text Available Puzzle hijaiyah Elektronik Interaktif adalah games edukasi kombinasi dari piranti lunak dan perangkat keras untuk membantu sarana pembelajaran anak-anak usia dini dalam pengenalan huruf-huruf hijaiyah Al-Quran. Pada saat penyusunan puzzle memiliki indikator berupa suara dan gambar animasi bergerak ketika penyusunan puzzle benar yang ditampilkan pada layar smartphone android. Pembuatan puzzle hijaiyah elektronik ini memanfaatkan alat-alat elektronik antara lain untuk membaca perubahan high atau low menggunakan sensor cahaya photodioda, untuk mengontrol menyala LED menggunakan IC demultiplexer, gerbang OR digunakan untuk menggabungkan keluaran dari setiap sensor dan memanfaatkan keluaran logika low, mikrokontroler DT-AVR Maxiduino sebagai pengontrol kerja komponen lain dan pengolah data yang diterima dari setiap sensor, Basic4Android sebagai editor pembuatan interface pada smartphone android yang digunakan untuk mengolah data yang dikirim dari mikrokontroler, bluetooth HC-06 sebagai alat komunikasi antara mikrokontroler dengan smartphone android. Pengujian alat ini berfungsi 100% dalam pengiriman dan penerimaan data melalui komunikasi bluetooth, alat ini berhasil dan dapat digunakan. Diharapkan dengan adanya alat ini dapat membuat anak-anak lebih tertarik lagi untuk belajar sehingga untuk belajar Al- quran dapat lebih menarik lagi dan dapat meningkatkan kemampuan berpikir dan membuat anak belajar berkonsentrasi. 

  7. A solution to B --> pi pi puzzle and B --> K K

    CERN Document Server

    Baek, Seungwon

    2008-01-01

    The large ratio of color-suppressed tree amplitude to color-allowed one in $B \\to \\pi \\pi$ decays is difficult to understand within the Standard Model, which is known as the "$B \\to \\pi\\pi$ puzzle". The two tree diagrams contain the up- and charm-quark component of penguin amplitude, $P_{uc}$, which cannot be separated by measuring $B \\to \\pi \\pi$ decays alone. We show that the measurements of the branching ratio and direct CP asymmetry of $B^+ \\to K^+ \\bar{K^0}$ decay enable one to disentangle the $P_{uc}$ with two-fold ambiguity. One of the two degenerate solutions of the $P_{uc}$ can solve the $B \\to \\pi \\pi$ puzzle by giving $|C/T|\\sim 0.3$ which is consistent with the expectation in the Standard Model. We also show that the two solutions can be discriminated by the measurement of the indirect CP-asymmetry of $B^0 \\to K^0 \\ol{K^0}$. We point out that if the $B \\to \\pi \\pi$ puzzle is solved in this way, the corresponding puzzle in $B \\to \\pi K$ decays should have a different origin.

  8. Cryptographic Puzzles and Game Theory against DoS and DDoS attacks in Networks

    DEFF Research Database (Denmark)

    Mikalas, Antonis; Komninos, Nikos; Prasad, Neeli R.

    2008-01-01

    . In the second part we are introducing some basic principles of game theory and we discuss how game theoretical frameworks can protect computer networks. Finally, we show techniques that combine client puzzles with game theory in order to provide DoS and DDoS resilience....

  9. Neutrino oscillations in magnetized media and implications for the pulsar velocity puzzle

    CERN Document Server

    Grasso, D

    1998-01-01

    After a brief presentation of the general techniques used to determine neutrino potentials in a magnetized medium I will discuss MSW resonant oscillations of active and sterile neutrinos in such environment. Using my results I will reconsider the viability of a solution of the pulsar velocity puzzle based on such a kind of neutrino oscillations.

  10. Puzzle task ERP response: time-frequency and source localization analysis

    Science.gov (United States)

    Almurshedi, Ahmed; Ismail, Abd Khamim

    2015-01-01

    Perceptual decision making depends on the choices available for the presented task. Most event-related potential (ERP) experiments are designed with two options, such as YES or NO. In some cases, however, subjects may become confused about the presented task in such a way that they cannot provide a behavioral response. This study aims to put subjects into such a puzzled state in order to address the following questions: How does the brain respond during puzzling moments? And what is the brain’s response to a non-answerable task? To address these questions, ERP were acquired from the brain during a scintillation grid illusion task. The subjects were required to count the number of illusory dots, a task that was impossible to perform. The results showed the presence of N130 over the parietal area during the puzzling task. Coherency among the brain hemispheres was enhanced with the complexity of the task. The neural generators’ source localizations were projected to a multimodal complex covering the left postcentral gyrus, supramarginal gyrus, and angular gyrus. This study concludes that the brain component N130 is strongly related to perception in a puzzling task network but not the visual processing network. PMID:28123804

  11. Gardner's Two Children Problems and Variations: Puzzles with Conditional Probability and Sample Spaces

    Science.gov (United States)

    Taylor, Wendy; Stacey, Kaye

    2014-01-01

    This article presents "The Two Children Problem," published by Martin Gardner, who wrote a famous and widely-read math puzzle column in the magazine "Scientific American," and a problem presented by puzzler Gary Foshee. This paper explains the paradox of Problems 2 and 3 and many other variations of the theme. Then the authors…

  12. A dialog with a puzzled profile: Poetry of an old pedological discussion

    Science.gov (United States)

    Itkin, Danny

    2017-04-01

    Defining and classifying are fundamental needs in the everyday life of humans. Among quite a few relevant examples in pedology, stands the question of whether soils and some types of sediments should or can be distinct. This issue is as old as soil science itself and is possibly very much related to the never ending debate regarding "the definition of soil". As is the case in many fields, the necessity of humans to create and keep a uniform common language might collide with different cultural and/or scientific perspectives. Such is the case with the wide variety of soil classifications found throughout the world. One can easily note this diversity when reading publications that address two similar regolith profiles from different locations round the globe. In some cases it would be impossible to correlate two comparable profiles when using different classification systems. This contradictory situation is one of the most challenging topics in pedology. This whole background gave the inspiration for the following poem, titled "A dialog with a puzzled profile": Are you a soil or a sediment? Ask the oak, see if he knows. Ask him whether these are peds Or maybe a bedrock under his toes. And if you're a soil, what are you? It depends on the viewpoint, you see: Some define me with Soil Taxonomy, While others with WRB. For Hutton and Lyell I'm a weathered rock, Yet Hilgard and Dokuchaev dispute. If you ask me, well I'm a 'pedosediment', I couldn't care less for the suit. If it helps you I'll be whatever it takes,
Making sure that no one will lose. I know it depends very much on the platform Where experts are setting the rules.

  13. The Puzzle of Non-proliferation and Disarmament (Part II); El puzzle de la No-Proliferacion y el Desarme (segunda parte)

    Energy Technology Data Exchange (ETDEWEB)

    Ponga, J. de

    2011-07-01

    Since, in 1945, the World was aware of the devastating power of nuclear weapons there have been many initiatives at international level to avoid nuclear weapon proliferation: the foundation of the IAEA, the NPT, the Safeguards Agreements, the Nuclear Weapon Free Zones, the treaties banning nuclear tests or the export control regime of the NSG, among others. This article aims to offer a general picture of all of them as pieces of a puzzle the purpose of which is not to allow gaps to non pacific uses of nuclear energy. (Author)

  14. Backus–Smith puzzle and the European Union: It’s not just the nominal exchange rate

    Directory of Open Access Journals (Sweden)

    Predrag Petrović

    2016-12-01

    Full Text Available he goal of our research is testing of presence and background examination of Backus–Smith puzzle in the EU. The research is based on the technique of econometric analysis of panel data, i.e. on the estimation of one-way/two-way error component models and models without effects. The results of the research have shown that: (a there is serious evidence on presence of the Backus–Smith puzzle in the EU, (b its background comprises both nominal exchange rate and inflation differential, and (c empirical data rejects complete risk sharing assumption strongly and decisively, but this does not explain the Backus–Smith puzzle. The basic conclusion of our research is that nominal exchange rate movements are not the only source of Backus–Smith puzzle in the EU, as is the case in OECD members states.

  15. A Characterization of Achievable Patterns of the MN—Puzzle Problem

    Institute of Scientific and Technical Information of China (English)

    杨红青

    1990-01-01

    One important MN-puzzle problem is to find a sequcence of up-down and ight-left movements of the empty-cell so that a goal-pattern can be achieved from a given initial-pattern.The second problem is to characterize the totality of the goal-pattrn from a given initial-pattern.The third problem is finding the fewest movements to achieve it.In this paper,these problems will be completely solved.

  16. The Puzzles of Politics: Inquiries into the genesis and transformation of international relations

    OpenAIRE

    KRATOCHWIL, Friedrich

    2011-01-01

    The Puzzles of Politics brings together for the first time a collection of his key essays to explain his approach to international relations and how his thinking has developed over the last 30 years. It addresses topical themes and issues central to his work including sovereignty, law, epistemology, boundaries, global governance and world society. The book includes a framing introduction written for this volume in which Kratochwil provides an intellectual biography providing context as well ...

  17. Understanding the proton radius puzzle: Nuclear structure effects in light muonic atoms

    Directory of Open Access Journals (Sweden)

    Ji Chen

    2016-01-01

    Full Text Available We present calculations of nuclear structure effects to the Lamb shift in light muonic atoms. We adopt a modern ab-initio approach by combining state-of-the-art nuclear potentials with the hyperspherical harmonics method. Our calculations are instrumental to the determination of nuclear charge radii in the Lamb shift measurements, which will shed light on the proton radius puzzle.

  18. Evolutionary, neurobiological, gene-based solution of the ideological "puzzle" of human altruism and cooperation.

    Science.gov (United States)

    Baschetti, Riccardo

    2007-01-01

    Despite hundreds of published articles about humankind's eusocial behaviours, most scholars still regard the origin of human altruism and cooperation as an enduring puzzle, because it seems incompatible with two central tenets of evolution, namely, the competition between individuals and the consequent selective advantages of selfish traits. This "puzzle", however, rather than being due to insurmountable scientific difficulties, is to be attributed to two powerful ideologies, which are politically opposite, but nevertheless concurred to prevent scholars from solving it. One ideology rejects the concept of genetic determinism, whereas the other dislikes the concept of group selection. As a consequence, these widespread ideologies, which are common in the scientific community, too, kept scholars from realising that the puzzle of human altruism and cooperation can only be solved by proposing a theoretical model that is based precisely on both genetic determinism and group selection. This model, which was never advanced in published papers, is presented here. This article also proposes to regard ancestral environments as determinants of human eusociality. By contrast, virtually all previous articles about it leave primitive habitats unmentioned. To support the hypothesis that human unselfish behaviours represent genetically conserved traits that evolved ancestrally, not products of cultural transmission, this paper also discusses six groups of arguments in the section "Genes versus culture". Finally, this article advances a purely genetic evolutionary explanation for the uniqueness of human eusociality, thereby challenging prevailing cultural explanations for the incomparably developed levels of cooperation in humankind, which are observed in no other social species.

  19. Padrão dos fluxos de capitais: teoria, evidência e puzzle

    Directory of Open Access Journals (Sweden)

    Aderbal Oliveira Damasceno

    2014-04-01

    Full Text Available Este trabalho desenvolve uma análise teórica e empírica sobre o padrão de longo prazo dos fluxos de capitais. Com uma amostra de 105 países e dados para o período 1980-2004, a metodologia econométrica abrange modelos para cross-section e para dados em painel. Os resultados apresentados sugerem: i incoerência entre as previsões do modelo neoclássico e o padrão observado dos fluxos de capitais, o que caracteriza o puzzle ; ii no âmbito da abordagem convencional, as explicações para o puzzle são diferenças de fundamentos entre países e imperfeições no mercado financeiro; iii não há evidências de que diferenças entre os países relativas ao ambiente institucional, estoque de capital humano, integração financeira, política macroeconòmica e desenvolvimento financeiro expliquem o puzzle. Considerando os resultados apresentados, esboça-se uma explicação alternativa de inspiração heterodoxa para o padrão dos fluxos de capitais.

  20. Toward a virtual reconstruction of an antique three-dimensional marble puzzle

    Science.gov (United States)

    Benamar, Fatima Zahra; Fauvet, Eric; Hostein, Antony; Laligant, Olivier; Truchetet, Frederic

    2017-01-01

    The reconstruction of broken objects is an important field of research for many applications, such as art restoration, surgery, forensics, and solving puzzles. In archaeology, the reconstruction of broken artifacts is a very time-consuming task due to the handling of fractured objects, which are generally fragile. However, it can now be supported by three-dimensional (3-D) data acquisition devices and computer processing. Those techniques are very useful in this domain because they allow the remote handling of very accurate models of fragile parts, they permit the extensive testing of reconstruction solutions, and they provide access to the parts for the entire research community. An interesting problem has recently been proposed by archaeologists in the form of a huge puzzle composed of a thousand fragments of Pentelic marble of different sizes found in Autun (France), and all attempts to reconstruct the puzzle during the last two centuries have failed. Archaeologists are sure that some fragments are missing and that some of the ones we have come from different slabs. We propose an inexpensive transportable system for 3-D acquisition setup and a 3-D reconstruction method that is applied to this Roman inscription but is also relevant to other applications.

  1. Puzzles on the duality between heterotic and type IIA strings

    CERN Document Server

    Abe, M; Abe, Mitsuko; Sato, Masamichi

    1999-01-01

    We discuss the possibility of the extension of the duality between the webs of heterotic string and the type IIA string to Calabi-Yau 3-folds with another K3 fiber by comparing the dual polyhedron of Calabi-Yau 3-folds given by Candelas, Perevalov and Rajesh.

  2. Quantum top secret. The solution of the quantum puzzle. Metamorphosis of a picture of world; Quantum top secret. Die Loesung des Quantenraetsels. Metamorphose eines Weltbildes

    Energy Technology Data Exchange (ETDEWEB)

    Wingert, M.

    2008-07-01

    Many physicists believe that because of unexplained causes, which must anyway be concerned with the quantum puzzle and the mysterious consciousness, it would be no more possible to understand the real structure of the reality - this subtle smiling of the nature, which irritates the physicists since 100 years and the disturbed the theoretical physics so much that they threw the towel. Since nature is considered as absurd, strange, and crazy - and quantum theory as very complicated. But in reality the basic experiments are of a touching simplicity, which seems only completely unintelligible in the picture of world of mechanics. For these experiments show that the concept of body of mechanics and the body conceptions of the thinking cannot at all match the structure of nature. If this is objectively taken notice of without doubting on the existence of a reality, the experiments show the real, unveiled face of the nature. Light and matter must then consist of fields, which can themselves divide by non-mechanical way, so with wholeness, comparable only with cell division and branching processes in biology. Either it is completely crazy - or the only logic interpretation, which hitherto only no physicist risked to think. For these experiments disprove the atom and elementary-particle hypothesis, the picture of world of mechanics, and also the quantum-mechanical interpretation - and indeed uniquely. This knowledge could break the Gordian knot, solve the quantum puzzle, and also give away the secret of the thinking spirit.

  3. Systematics for low energy incomplete fusion: Still a puzzle?

    Directory of Open Access Journals (Sweden)

    Yadav Abhishek

    2016-01-01

    Full Text Available In order to have a better and clear picture of incomplete fusion reactions at energies ≈4-7MeV/nucleon, the excitation function measurements have been performed for 18O+159Tb system. The experimental data have been analyzed within the framework of compound nucleus decay. The cross-section for xn/pxn-channels are found to be well reproduced by PACE4 predictions, which suggest their production via complete fusion process. However, a significant enhancement in the excitation functions of α-emitting channels has been observed over the theoretical ones, which has been attributed due to the incomplete fusion processes. The incomplete fusion fractions have been deduced at each studied energy and compared with other nearby systems for better insight into the underlying dynamics. The incomplete fusion fraction has been found to be sensitive to the projectile’s energy and α-Q-value.

  4. Is New Zealand vegetation really 'problematic'? Dansereau's puzzles revisited.

    Science.gov (United States)

    Wilson, J Bastow; Lee, William G

    2012-05-01

    Over four decades ago, Pierre Dansereau, the noted North American ecologist, proposed six features of New Zealand vegetation as being problematic or unusual in a global context. We examine his propositions in the light of current ecological knowledge to determine whether or not these can still be considered unusual characteristics of New Zealand vegetation. (1) 'Climatic change is still progressing' resulting in disequilibrium between species' distributions and the present climate. New data and methods of analysis now available have removed the impression that Dansereau gained of imprecise zonation, unclear vegetation/climate relations and missing vegetation types. Communities cited as having regeneration failure can now be seen as even-aged stands that developed after major disturbance, although there are other, also non-climatic, explanations. However, the cause of the Westland 'Nothofagus gap' has become more, rather than less, controversial. (2) 'Continuity of community composition defies classification' and 'Very few New Zealand associations have faithful species' are correct observations, but perhaps equally true of vegetation elsewhere. Dansereau's assertion of low species richness in New Zealand is not supported by the comparative data available. (3) 'Lack of intolerant [i.e. mid-seral] trees …' is not evident with newer information. The order of species in succession, seen as unclear by Dansereau, has been determined by a range of approaches, largely confirming each other. (4) 'Discrepancies of form and function …' in divaricate shrubs and widespread heteroblasty are still controversial, with many more explanations. Several abiotic explanations have failed to stand up to investigation. Explanations in terms of herbivory have been well supported, although the extinction of the large avian herbivores makes certainty impossible. (5) 'Incidence of hybridization …' remains problematic. We do not know whether the incidence is unusually high, as Dansereau

  5. Pull or Push? Octopuses Solve a Puzzle Problem

    Science.gov (United States)

    Richter, Jonas N.; Hochner, Binyamin; Kuba, Michael J.

    2016-01-01

    Octopuses have large brains and exhibit complex behaviors, but relatively little is known about their cognitive abilities. Here we present data from a five-level learning and problem-solving experiment. Seven octopuses (Octopus vulgaris) were first trained to open an L shaped container to retrieve food (level 0). After learning the initial task all animals followed the same experimental protocol, first they had to retrieve this L shaped container, presented at the same orientation, through a tight fitting hole in a clear Perspex partition (level 1). This required the octopuses to perform both pull and release or push actions. After reaching criterion the animals advanced to the next stage of the test, which would be a different consistent orientation of the object (level 2) at the start of the trial, an opaque barrier (level 3) or a random orientation of the object (level 4). All octopuses were successful in reaching criterion in all levels of the task. At the onset of each new level the performance of the animals dropped, shown as an increase in working times. However, they adapted quickly so that overall working times were not significantly different between levels. Our findings indicate that octopuses show behavioral flexibility by quickly adapting to a change in a task. This can be compared to tests in other species where subjects had to conduct actions comprised of a set of motor actions that cannot be understood by a simple learning rule alone. PMID:27003439

  6. Some issues concerning the proton charge radius puzzle

    CERN Document Server

    Walcher, Thomas

    2012-01-01

    An explanation of the difference of the charge radius of the proton as determined from the Lamb shift in electronic hydrogen and from elastic electron scattering off the proton on the one side and the recent high precision determination with muonic hydrogen on the other side is presented. It is shown that the modification of the $2S_{1/2}$ and $2P_{3/2}$ wave functions by the "Uehling potential" yields a correction to the theoretical Lamb shift of $\\delta (\\Delta E_{\\textrm{Lamb}}) = 0.302$ meV which has to be compared to $\\delta (\\Delta E_{\\textrm{Lamb}}) = 0.322(46)$ meV equivalent to the stated radius difference. The explanation is based on the realization that the bound state wave functions modified by the external "Uehling potential" have to be propagated by the vacuum polarization propagator in order to give the correct leading order Lamb shift. It is argued that a conflicting relativistic calculation neglects this propagation aspect. The explanation demonstrates that the Lamb shift is dynamically induc...

  7. Pull or Push? Octopuses Solve a Puzzle Problem.

    Directory of Open Access Journals (Sweden)

    Jonas N Richter

    Full Text Available Octopuses have large brains and exhibit complex behaviors, but relatively little is known about their cognitive abilities. Here we present data from a five-level learning and problem-solving experiment. Seven octopuses (Octopus vulgaris were first trained to open an L shaped container to retrieve food (level 0. After learning the initial task all animals followed the same experimental protocol, first they had to retrieve this L shaped container, presented at the same orientation, through a tight fitting hole in a clear Perspex partition (level 1. This required the octopuses to perform both pull and release or push actions. After reaching criterion the animals advanced to the next stage of the test, which would be a different consistent orientation of the object (level 2 at the start of the trial, an opaque barrier (level 3 or a random orientation of the object (level 4. All octopuses were successful in reaching criterion in all levels of the task. At the onset of each new level the performance of the animals dropped, shown as an increase in working times. However, they adapted quickly so that overall working times were not significantly different between levels. Our findings indicate that octopuses show behavioral flexibility by quickly adapting to a change in a task. This can be compared to tests in other species where subjects had to conduct actions comprised of a set of motor actions that cannot be understood by a simple learning rule alone.

  8. Is the proton radius puzzle an evidence of extra dimensions?

    CERN Document Server

    Dahia, F

    2015-01-01

    The proton charge radius inferred from muonic hydrogen spectroscopy is not compatible with the previous value given by CODATA-2010, which, on its turn, essentially relies on measurements of the electron-proton interaction. The proton's new size was extracted from the 2S-2P Lamb shift in the muonic hydrogen, which showed an energy excess of 0.3 meV in comparison to the theoretical prediction, evaluated with the CODATA radius. Higher-dimensional gravity is a candidate to explain this discrepancy, since the muon-proton gravitational interaction is stronger than the electron-proton interaction and, in the context of braneworld models, the gravitational potential can be hugely amplified in short distances when compared to the Newtonian potential. Motivated by these ideas, we study a muonic hydrogen confined in a thick brane. We show that the muon-proton gravitational interaction modified by extra dimensions can provide the additional separation of 0.3 meV between 2S and 2P states. In this scenario, the gravitation...

  9. Renalase: Another puzzle piece between hypertension and simple renal cysts?

    Science.gov (United States)

    Elcioglu, Omer Celal; Afsar, Baris; Takir, Mumtaz; Toprak, Aybala Erek; Bakan, Ali; Bakan, Sibel; Kostek, Osman; Oral, Alihan; Erman, Hayriye; Covic, Adrian; Kanbay, Mehmet

    2015-07-01

    Since renalase is mostly expressed in kidney tubules, simple renal cyst (SRC) originates from the kidney tubules, and both conditions are related to hypertension, it may be possible that SRC is associated with increased renalase levels. Therefore, in the current study we aimed to confirm the relation between renalase and epinephrine levels, the association between SRC and renalase levels and the association between renalase, blood pressure levels and endothelial dysfunction. We made a cross-sectional study including 75 patients with SRC, and 51 controls were included to the study. Flow-mediated dilatation (FMD) was assessed, and serum renalase and epinephrine levels were determined. Patient with SRC had lower renalase, higher epinephrine and lower FMD levels when compared to patients without SRC (p < 0.05). Log renalase was correlated with log epinephrine (r = -0.302, p = 0.001) and log FMD (r = 0.642, p < 0.0001). There was no correlation between renalase and urine albumin/creatinine ratio and glomerular filtration rate. In univariate analysis, age, glomerular filtration rate, renalase and FMD were associated with the presence of SRC. Multivariate regression analysis of factors which are statistically significant in univariate analysis showed that age and renalase was associated with the presence of SRC. We have demonstrated that renalase levels were associated with the presence of SRC and endothelial dysfunction. Further research is necessary to highlight underlying mechanisms.

  10. The rise of C4 grassland ecosystems, a climate puzzle

    Science.gov (United States)

    Henderson, A.; Fox, D.; Freeman, K. H.

    2011-12-01

    The expansion of grasslands was one of the most profound ecological changes in the Cenozoic. Understanding the history of forest to grassland transitions, and the development of C4 grasslands in particular, is critical for understanding the relationship between land surface climate feedbacks, seasonality, and temperature. Modern distributions and ecological experiments demonstrate a strong correlation between C4 biogeography and high growing season temperatures and precipitation, as well as low pCO2 concentrations. The rise of C4 grasses in North America, as documented by carbonate nodule and mammal teeth δ13C values, began during a warm period with relatively stable pCO2 in the late Miocene. Surprisingly, C4 grasses continued to expand and then rose to dominance in the Great Plains as climates progressively cooled, moisture availability increased, and ice sheets formed further north on the continent. To understand this seemingly paradoxical scenario, we need constraints on the rate and character of increasing abundances of C4 vegetation. To this end, we use molecular and isotopic tools from terrestrial plant leaf wax n-alkanes extracted from carbonate nodules in the Meade Basin, Kansas and sites in Texas for the past 12 Ma. These records offer site-specific reconstructions tied directly to vegetation source. We compare our results to published continental-scale reconstructions of n-alkanes from the Mississippi River drainage basin and to climate records. From the distribution of C27 to C33 n-alkane abundances and patterns in δ13C values, we infer that C4 grasses coexisted with patches of C3 vegetation, including both grasses and trees. C4 grasses increasingly dominated the landscape, reaching modern abundances as ice sheets were reaching their southern limit in North America. Our results confirm that C4 grasslands emerged under cool and wet conditions, something we would not predict based on modern analogues, raising questions about our understanding of the

  11. The puzzling structure in Saturn's outer B ring

    Science.gov (United States)

    Nicholson, Philip D.; Hedman, Matt; Buckingham, Rikley

    2017-06-01

    As first noted in Voyager images, the outer edge of Saturn's B ring is strongly perturbed by the 2:1 inner Lindblad resonance with Mimas (Porco \\etal\\ 1984). Cassini imaging and occultation data have revealed a more complex situation, where the expected resonantly-forced m=2 perturbation with an amplitude of 33~km is accompanied by freemodes with m=1, 2, 3, 4 and 5 (Spitale & Porco 2010, Nicholson \\etal\\ 2014a). To date, however, the structure immediately interior to the ring edge has not been examined carefully. We have compared optical depth profiles of the outer 1000~km of the B ring, using a large set of stellar occultations carried out since 2005 by the Cassini VIMS instrument. A search for wavelike structure, using a code written to search for hidden density waves (Hedman \\& Nicholson 2016), reveals a significant signature at a radius of ~117,150 km with a radial wavelength of ~110 km. This appears to be a trailing spiral with m=1 and a pattern speed equal to the local apsidal precession rate, $\\dpi\\simeq5.12\\dd$. Further searches for organized large-scale structure have revealed none with m=2 (as might have been expected), but several additional regions with significant m=1 variations and pattern speeds close to the local value of $\\dpi$. At present, it is unclear if these represent propagating spirals, standing waves, or perhaps features more akin to the eccentric ringlets often seen within gaps in the C ring and Cassini Division (Nicholson \\etal\\ 2014b, French \\etal\\ 2016). Comparisons of sets of profiles from 2008/9, 2012-14 and 2016 seem to show that these structures are changing over time.

  12. Puzzles of J/{Psi} production off nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Kopeliovich, B.Z., E-mail: boris.kopeliovich@mpi-hd.mpg.d [Departamento de Fisica, Universidad Tecnica Federico Santa Maria, and Instituto de Estudios Avanzados en Ciencias e Ingenieria, and Centro Cientifico-Tecnologico de Valparaiso, Casilla 110-V, Valparaiso (Chile)

    2011-03-15

    Nuclear effects for J/{Psi} production in pA collisions are controlled by the coherence and color transparency effects. Color transparency onsets when the time of formation of the charmonium wave function becomes longer than the inter-nucleon spacing. In this energy regime the effective break-up cross section for a c-barc dipole depends on energy and nuclear path length, and agrees well with data from fixed target experiments, both in magnitude and energy dependence. At higher energies of RHIC and LHC coherence in c-barc pair production leads to charm quark shadowing which is a complement to the high twist break up cross section. These two effects explain well with no adjusted parameters the magnitude and rapidity dependence of nuclear suppression of J/{Psi} observed at RHIC in dAu collisions, while the contribution of leading twist gluon shadowing is found to be vanishingly small. A novel mechanism of double color filtering for c-barc dipoles makes nuclei significantly more transparent in AA compared to pA collisions. This is one of the mechanisms which make impossible a model independent 'data driven' extrapolation from pA to AA. This effect also explains the enhancement of nuclear suppression observed at forward rapidities in AA collisions at RHIC, what hardly can be related to the produced dense medium. J/{Psi} is found to be a clean and sensitive tool measuring the transport coefficient characterizing the dense matter created in AA collisions. RHIC data for p{sub T} dependence of J/{Psi} production in nuclear collisions are well explained with the low value of the transport coefficient q-hat{sub 0}<0.5 GeV{sup 2}/fm.

  13. Republic of South Africa: unraveling the population puzzle. Country profile.

    Science.gov (United States)

    Spain, D

    1984-06-01

    whites it was only 1.5%. The birthrate among whites in 1980 was 16.5 births/1000 whites compared with 40 births/1000 blacks. Immigration has played an important role in South Africa's white population growth. Net migration in 1981 was 33,000; 55% of new arrivals were from Europe and 40% were from other African countries. In 1980, just over half the population (53%) lived in urban areas. Approximately 90% of whites and Asians lived in urban areas, while 3/4 of coloureds and 38% of blacks were classified as urban. understanding South Africa's racial and ethnic divisions is the key to understanding the country. Political and social interaction across racial lines is forbidden. Economic relationships are strictly controlled by the passbrook system. The passbook, which must be carried by every black aged 16 and olfder, establishes a black's right to be in a particular area of the country. South Africa's population is fairly young due to a history of high fertility and high mortality among blacks, coloureds, and Asias. For the population as a whole, 38% were under age 15 in 1980 and 4% were aged 65 and older. Whites accounted for 22% and blacks 64% of the labor force in 1980. The government has tried to narrow the wage gap between white and black workers. In 1972 blacks earned only 15% of whites salaries; by 1981 black wages were 24% of white wages.

  14. Does random tree puzzle produce Yule-Harding trees in the many-taxon limit?

    Science.gov (United States)

    Zhu, Sha; Steel, Mike

    2013-05-01

    It has been suggested that a random tree puzzle (RTP) process leads to a Yule-Harding (YH) distribution, when the number of taxa becomes large. In this study, we formalize this conjecture, and we prove that the two tree distributions converge for two particular properties, which suggests that the conjecture may be true. However, we present statistical evidence that, while the two distributions are close, the RTP appears to converge on a different distribution than does the YH. By way of contrast, in the concluding section we show that the maximum parsimony method applied to random two-state data leads a very different (PDA, or uniform) distribution on trees.

  15. A Game Architecture for Emergent Story-Puzzles in a Persistent World

    OpenAIRE

    Peinado, Federico

    2005-01-01

    This paper presents the design of a semi-emergent architecture for graphic adventures. The proposed architecture is able to create new significant story-puzzles on the fly, combining preauthored material in a coherent and emergent way. As a test-bed of this architecture we use a simple detective game inspired on the famous boardgame Cluedo. INTRODUCTION There are a lot of adventure games in the market and some of them try to tell a re-playable story that change and become slightly different f...

  16. High-energy cosmic rays: Puzzles, models, and giga-ton neutrino telescopes

    Indian Academy of Sciences (India)

    E Waxman

    2004-02-01

    The existence of cosmic rays of energies exceeding 1020 eV is one of the mysteries of high-energy astrophysics. The spectrum and the high energy to which it extends rule out almost all suggested source models. The challenges posed by observations to models for the origin of high-energy cosmic rays are reviewed, and the implications of recent new experimental results are discussed. Large area high-energy cosmic ray detectors and large volume high-energy neutrino detectors currently under construction may resolve the high-energy cosmic ray puzzle, and shed light on the identity and physics of the most powerful accelerators in the Universe.

  17. Exchange rate regimes, saving glut and the Feldstein Horioka puzzle: The East Asian experience

    Science.gov (United States)

    Kaya-Bahçe, Seçil; Özmen, Erdal

    2008-04-01

    This paper investigates whether the recent experience of the emerging East Asian countries with current account surpluses is consistent with the “saving glut” hypothesis and the Feldstein and Horioka puzzle. The evidence suggests that the saving retention coefficients declined substantially in most of the countries after an endogenous break date coinciding with a major exchange rate regime change with the 1997-1998 crisis. Exchange rate flexibility appears to be enhancing financial integration. The results are consistent with an “investment slump” explanation rather than the “saving glut” postulation.

  18. The Resolution of an Entropy Puzzle for 4D non-BPS Black Holes

    CERN Document Server

    Banerjee, Nabamita; Lodato, Ivano

    2016-01-01

    We show the equality between macroscopic and microscopic black hole entropy for a class of four dimensional non-supersymmetric black holes in ${\\cal N}=2$ supergravity theory, up to the first subleading order in their charges. This solves a long standing entropy puzzle for this class of black holes. The macroscopic entropy has been computed in the presence of a newly derived higher-derivative supersymmetric invariant of \\cite{{Butter:2013lta}}, connected to the five dimensional supersymmetric Weyl squared Lagrangian. Microscopically, the crucial role in obtaining the equivalence is played by the anomalous gauge gravitational Chern-Simons term.

  19. A 17 keV neutrino and large magnetic moment solution of the solar neutrino puzzle

    Science.gov (United States)

    Akhmedov, E. Kh.; Senjanovic, G.; Tao, Zhijian; Berezhiani, Z. G.

    1992-08-01

    Zee-type models with Majorons naturally incorporate the 17 keV neutrino but in their minimal version fail to simultaneously solve the solar neutrino puzzle. If there is a sterile neutrino state, a particularly simple solution is found to the solar neutrino problem, which besides nu(sub 17) predicts a light Zeldovich-Konopinski-Mahmoud neutrino nu(sub light) = nu(sub e) + nu(sub mu)(sup c) with a magnetic moment being easily as large as 10(exp -11)(mu)(sub B) through the Barr-Freire-Zee mechanism.

  20. 17 keV neutrino and large magnetic moment solution of the solar neutrino puzzle

    Science.gov (United States)

    Akhmedov, Eugeni Kh.; Berezhiani, Zurab G.; Senjanović, Goran; Tao, Zhijian

    1993-01-01

    Zee-type models with majorons naturally incorporate the 17 keV neutrino but in their minimal version fail to simultaneously solve the solar neutrino puzzle. If there is a sterile neutrino state, we find a particularly simple solution to the solar neutrino problem, which besides ν17 predicts a light Zeldovich-Konopinski-Mahmoud neutrino νlight = νe + νcμ with a magnetic moment being easily as large as 10 -11μB through the Barr-Freire-Zee mechanism.

  1. Puzzling asymmetries

    CERN Multimedia

    Antonella Del Rosso

    2012-01-01

    In a recently published paper, the LHCb collaboration reported on a possible deviation from the Standard Model. Theorists are now working to calculate precisely this effect and to evaluate the implications that such an unexpected result could have on the established theory.   The Standard Model is able to predict the decay rates of particles with high precision. In most cases, experimentalists confirm the value predicted by theory and the figure is added to the official publications. However, this time, things seem to have taken a different route. Studying data collected in 2011, the LHCb collaboration found that in a specific decay – a B particle transforming into a K particle plus two charged muons (B -> Kμ-μ+) – the branching ratio of the neutral B in the corresponding decay (i.e. B0 -> K0μ-μ+) was different it that of the positively charged B (i.e. B+ -> K+μ-μ+). Such an “isospin asymmetry”...

  2. Puzzling asymmetries

    CERN Multimedia

    Antonella Del Rosso

    2012-01-01

    In a recently published paper, the LHCb Collaboration has reported on a possible deviation from the Standard Model. Theorists are now working to calculate precisely this effect and to evaluate the implications that such unexpected result could have on the established theory.   The Standard Model is able to predict the decay rates of particles with high precision. In most cases, experimentalists confirm the value predicted by theory and the figure is added to the official publications. However, this time, things seem to have taken a different route. Studying data collected in 2011, the LHCb Collaboration found that in a specific decay – a B particle transforming into a K particle plus two charged muons (B -> Kμ-μ+) – the branching ratio of the neutral B in the corresponding decay (i.e. B0 -> K0μ-μ+) is different from that of the positively charged B (i.e. B+ -> K+μ-μ+). Such an “isospin asymmetry&rdquo...

  3. Puzzling antimatter

    CERN Multimedia

    Francesco Poppi

    2010-01-01

    For many years, the absence of antimatter in the Universe has tantalised particle physicists and cosmologists: while the Big Bang should have created equal amounts of matter and antimatter, we do not observe any primordial antimatter today. Where has it gone? The LHC experiments have the potential to unveil natural processes that could hold the key to solving this paradox.   Every time that matter is created from pure energy, equal amounts of particles and antiparticles are generated. Conversely, when matter and antimatter meet, they annihilate and produce light. Antimatter is produced routinely when cosmic rays hit the Earth's atmosphere, and the annihilations of matter and antimatter are observed during physics experiments in particle accelerators. If the Universe contained antimatter regions, we would be able to observe intense fluxes of photons at the boundaries of the matter/antimatter regions. “Experiments measuring the diffuse gamma-ray background in the Universe would be able...

  4. Toward a solution to the $R_{AA}$ and $v_2$ puzzle for heavy quarks

    CERN Document Server

    Das, Santosh K; Plumari, Salvatore; Greco, Vincenzo

    2015-01-01

    The heavy quarks constitutes a unique probe of the quark-gluon plasma properties. Both at RHIC and LHC energies a puzzling relation between the nuclear modification factor $R_{AA}(p_T)$ and the elliptic flow $v_2(p_T)$ has been observed which challenged all the existing models, especially for D mesons. We discuss how the temperature dependence of the heavy quark drag coefficient is responsible to address for a large part of such a puzzle. In particular, we have considered four different models to evaluate the temperature dependence of drag and diffusion coefficients propagating through a quark gluon plasma (QGP). All the four different models are set to reproduce the same $R_{AA}(p_T)$ observed in experiments at RHIC and LHC energy. We point out that for the same $R_{AA}(p_T)$ one can generate 2-3 times more $v_2$ depending on the temperature dependence of the heavy quark drag coefficient. An increasing drag coefficient as $ T \\rightarrow\\ T_c \\,$ is a major ingredient for a simultaneous description of $R_{AA...

  5. Toward a solution to the RAA and v2 puzzle for heavy quarks

    Directory of Open Access Journals (Sweden)

    Santosh K. Das

    2015-07-01

    Full Text Available The heavy quarks constitute a unique probe of the quark–gluon plasma properties. A puzzling relation between the nuclear modification factor RAA(pT and the elliptic flow v2(pT has been observed both at RHIC and LHC energies. Predicting correctly both observables has been a challenge to all existing models, especially for D mesons. We discuss how the temperature dependence of the heavy quark drag coefficient is responsible for a large part of such a puzzle. In particular, we have considered four different models to evaluate the temperature dependence of drag and diffusion coefficients propagating through a quark gluon plasma (QGP. All the four different models are set to reproduce the same RAA(pT observed in experiments at RHIC and LHC energy. We point out that for the same RAA(pT one can generate 2–3 times more v2 depending on the temperature dependence of the heavy quark drag coefficient. A non-decreasing drag coefficient as T→Tc is a major ingredient for a simultaneous description of RAA(pT and v2(pT.

  6. Eta Carinae: A Box of Puzzles...Some Solved, Others Await

    Science.gov (United States)

    Gull, Theodore

    2010-01-01

    In the l840's, Eta Carinae brightened to rival Sirius, then faded. Today we see a marginally naked-eye binary with an expanding, very dusty bipolar Homunculus. The energetics of the ejected mass (>l2 to 40 solar masses at 500-700 km/s plus outer bullets/strings up to 3000 km/s} approach that of a supernova. Extragalactic SN surveys detect near-supernovae thought to be like the Great Eruption of the 1840's. Eta Carinae presents an abundance of puzzles: rich in N, but 1/100th the solar C and O abundances; Ti, V, Sr, Sc persist in atomic states.... yet an abundance of molecules and dust exists in the Homunculus. How did molecules and dust form with low C and O? A near supernova occurred in the l840m, yet both binary companions, with total mass > 120 solar masses, survive in a very eccentric orbit. What is the near future of this system: a GRB? a SN? or just two WR stars that ultimately become two SNs? These and other puzzles will be presented

  7. Simultaneous explanation of the RK and R(D(⁎ puzzles

    Directory of Open Access Journals (Sweden)

    Bhubanjyoti Bhattacharya

    2015-03-01

    Full Text Available At present, there are several hints of lepton flavor non-universality. The LHCb Collaboration has measured RK≡B(B+→K+μ+μ−/B(B+→K+e+e−, and the BaBar Collaboration has measured R(D(⁎≡B(B¯→D(⁎+τ−ν¯τ/B(B¯→D(⁎+ℓ−ν¯ℓ (ℓ=e,μ. In all cases, the experimental results differ from the standard model predictions by 2–3σ. Recently, an explanation of the RK puzzle was proposed in which new physics (NP generates a neutral-current operator involving only third-generation particles. Now, assuming the scale of NP is much larger than the weak scale, this NP operator must be made invariant under the full SU(3C×SU(2L×U(1Y gauge group. In this Letter, we note that, when this is done, a new charged-current operator can appear, and this can explain the R(D(⁎ puzzle. A more precise measurement of the double ratio R(D/R(D⁎ can rule out this model.

  8. The Equity Premium Puzzle: Analysis in Brazil after the Real Plan

    Directory of Open Access Journals (Sweden)

    Fábio Augusto Reis Gomes

    2013-04-01

    Full Text Available Our paper investigates whether there is evidence of an Equity Premium Puzzle (EPP in Brazil, applying two different methodologies. The EPP was identified by Mehra and Prescott (1985 since the Consumption Capital Asset Pricing Model (CCAPM, when calibrated with reasonable preference parameters, could not explain high historical average risk premiums in the United States. In our first approach, we consider Mehra’s (2003 model and calibrate the coefficient of risk aversion, using 1995:2-2012:1 quarterly data. The Ibovespa index was used as a measure of the market return, whereas the risk-free rate was proxied by the Selic interbank rate and by the savings account rate. In our second approach, we propose a new method to test the puzzle. We jointly estimate, via generalized method of moments, the parameters of interest using a moment condition that has not been previously explored, as far as we are aware of. The two approaches produced a high risk aversion coefficient, however the second approach indicated that we cannot reject the hypothesis of the risk aversion coefficient being statistically equal to zero. A possible explanation for this result might be that in Brazil the equity premium is not statistically different from zero. Therefore there is no evidence of EPP in Brazil for the studied period.

  9. Heavy flavor puzzle at LHC: a serendipitous interplay of jet suppression and fragmentation.

    Science.gov (United States)

    Djordjevic, Magdalena

    2014-01-31

    Both charged hadrons and D mesons are considered to be excellent probes of QCD matter created in ultrarelativistic heavy ion collisions. Surprisingly, recent experimental observations at LHC show the same jet suppression for these two probes, which--contrary to pQCD expectations--may suggest similar energy losses for light quarks and gluons in the QCD medium. We here use our recently developed energy loss formalism in a finite-size dynamical QCD medium to analyze this phenomenon that we denote as the "heavy flavor puzzle at LHC." We show that this puzzle is a consequence of an unusual combination of the suppression and fragmentation patterns and, in fact, does not require invoking the same energy loss for light partons. Furthermore, we show that this combination leads to a simple relationship between the suppressions of charged hadrons and D mesons and the corresponding bare quark suppressions. Consequently, a coincidental matching of jet suppression and fragmentation allows considerably simplifying the interpretation of the corresponding experimental data.

  10. Understanding the ``Proton Radius Puzzle'': Nuclear Polarizability Correction in μD

    Science.gov (United States)

    Hernandez, Oscar J.; Dinur, Nir Nevo; Ji, Chen; Bacca, Sonia; Barnea, Nir

    2016-09-01

    The accuracy of the proton radius was improved ten-fold by new spectroscopic measurements in muonic hydrogen but it differs by 7 σ from hydrogen determinations. This discrepancy, has been coined the ``proton radius puzzle''. The results of new high-precision experiments on muonic deuterium indicate a new deuterium radius puzzle. The accuracy of the nuclear charge radius determination from these measurements is limited by the uncertainty in the nuclear structure effects. We have calculated this correction in Ref. including the first estimate of the nuclear-model dependence. Due to the importance of constraining the uncertainty, we will determine the statistical and systematic uncertainties of the χEFT potentials by determining the co-variance matrices of our predictions. I will also discuss an alternate method that may reduce the theoretical uncertainty. TRIUMF receives federal funding via a contribution agreement with the National Research Council of Canada. This work was supported in parts by the Natural Sciences and Engineering Research Council (Grant Number SAPIN-2015-00031).

  11. Solving the Solar Neutrino Puzzle with KamLAND and Solar Data

    CERN Document Server

    De Gouvêa, A; Gouv\\^ea, Andr\\'e de

    2001-01-01

    We study what will be learnt about the solar neutrino puzzle and solar neutrino oscillations once the data from the KamLAND reactor neutrino experiment (soon to become available) are combined with those from the current solar neutrino experiments. We find that, in agreement with previous estimates, if the solution to the solar neutrino puzzle falls on the LMA region, KamLAND should be able to ``pin-point'' the right solution with unprecedented accuracy after a few years of data taking. Furthermore, the light side ($\\theta\\pi/4$) at the 95% confidence level (CL) for most of the LMA region allowed by the current data at the 99% CL, while the addition of the KamLAND data need not improve our ability to limit a sterile component in ``solar'' oscillations. If KamLAND does not see an oscillation signal, the solar data would point to the LOW/VAC regions, while the SMA region would still lurk at the two sigma CL, meaning we would probably have to wait for Borexino data in order to finally piece the solar neutrino puz...

  12. Jigsaw puzzle of tourism destination image and its evaluation index%旅游目的地形象“拼图”及测评方法

    Institute of Scientific and Technical Information of China (English)

    吴晋峰

    2014-01-01

    根据格式塔心理学理论,借用拼图和七巧板概念进一步阐释旅游目的地形象定义、维度和属性,构建旅游目的地形象拼图过程模型,提出可用于对比研究目的地形象的测评指标体系,并以中国国际旅游形象为例进行实证分析。结果表明:(1)目的地形象是人们对自己大脑中获得的有关旅游目的地各种信息“零片”进行“拼图”的结果。(2)“拼图”过程是导致目的地形象具有复杂性、多样性和动态性的根本原因,也是目的地形象策划和形象营销能产生市场劝说作用的依据所在。(3)目的地形象可划分为旅游吸引物、基础设施、休闲和娱乐、环境和地方氛围等5个维度,每个维度包含不同的属性。(4)旅游者了解的目的地形象维度越完整、每个维度的属性越丰富,其对目的地的形象拼图结果越接近目的地实际情况。(5)目的地形象形成过程包括零片阶段、拼图阶段、情感评价和意动等四个阶段及自发拼图形成原生形象、自觉拼图形成认知形象和修正拼图形成整体形象3个渐进过程。(6)目的地形象可用 D m、L a、H 、E 和 D 等指标定量测评。%For more in-depth understanding of tourism destination image (TDI),according to Gestalt psychology theory,jigsaw puzzle and tangram concepts were borrowed to further explain the definition of the concept of tourism destination image,its dimensions and properties,and a tourism destination image puzzles process model that can be used to comparative study of TDI was built.Furthermore,a case study of the China international tourism image was analyzed.The main conclusions are as follow:(1)TDI is the “puzzle result”of information fragment that people getting form multiple channels about a tourism destination,not just an individual′s overall perception or total set of impressions of a destination.(2)The “puzzle process”leads to

  13. An Effective Method of Introducing the Periodic Table as a Crossword Puzzle at the High School Level

    Science.gov (United States)

    Joag, Sushama D.

    2014-01-01

    A simple method to introduce the modern periodic table of elements at the high school level as a game of solving a crossword puzzle is presented here. A survey to test the effectiveness of this new method relative to the conventional method, involving use of a wall-mounted chart of the periodic table, was conducted on a convenience sample. This…

  14. An Effective Method of Introducing the Periodic Table as a Crossword Puzzle at the High School Level

    Science.gov (United States)

    Joag, Sushama D.

    2014-01-01

    A simple method to introduce the modern periodic table of elements at the high school level as a game of solving a crossword puzzle is presented here. A survey to test the effectiveness of this new method relative to the conventional method, involving use of a wall-mounted chart of the periodic table, was conducted on a convenience sample. This…

  15. Pieces of the Puzzle: Factors in the Improvement of Urban School Districts on the National Assessment of Educational Progress. Abstract

    Science.gov (United States)

    Casserly, Michael; Price-Baugh, Ricki; Corcoran, Amanda; Lewis, Sharon; Uzzell, Renata; Simon, Candace; Heppen, Jessica; Leinwand, Steve; Salinger, Terry; de Mello, Victor Bandeira; Dogan, Enis; Novotny, Laura

    2011-01-01

    This is an abridged, summary report of selected findings from "Pieces of the Puzzle: Factors in the Improvement of Urban School Districts on the National Assessment of Educational Progress"--a comprehensive study prepared by the Council of the Great City Schools in collaboration with the American Institutes for Research (AIR) and with…

  16. Defense of the Least Squares Solution to Peelle’s Pertinent Puzzle

    Directory of Open Access Journals (Sweden)

    Nicolas Hengartner

    2011-02-01

    Full Text Available Generalized least squares (GLS for model parameter estimation has a long and successful history dating to its development by Gauss in 1795. Alternatives can outperform GLS in some settings, and alternatives to GLS are sometimes sought when GLS exhibits curious behavior, such as in Peelle’s Pertinent Puzzle (PPP. PPP was described in 1987 in the context of estimating fundamental parameters that arise in nuclear interaction experiments. In PPP, GLS estimates fell outside the range of the data, eliciting concerns that GLS was somehow flawed. These concerns have led to suggested alternatives to GLS estimators. This paper defends GLS in the PPP context, investigates when PPP can occur, illustrates when PPP can be beneficial for parameter estimation, reviews optimality properties of GLS estimators, and gives an example in which PPP does occur.

  17. Gold-nanoparticle-mediated jigsaw-puzzle-like assembly of supersized plasmonic DNA origami.

    Science.gov (United States)

    Yao, Guangbao; Li, Jiang; Chao, Jie; Pei, Hao; Liu, Huajie; Zhao, Yun; Shi, Jiye; Huang, Qing; Wang, Lianhui; Huang, Wei; Fan, Chunhai

    2015-03-02

    DNA origami has rapidly emerged as a powerful and programmable method to construct functional nanostructures. However, the size limitation of approximately 100 nm in classic DNA origami hampers its plasmonic applications. Herein, we report a jigsaw-puzzle-like assembly strategy mediated by gold nanoparticles (AuNPs) to break the size limitation of DNA origami. We demonstrated that oligonucleotide-functionalized AuNPs function as universal joint units for the one-pot assembly of parent DNA origami of triangular shape to form sub-microscale super-origami nanostructures. AuNPs anchored at predefined positions of the super-origami exhibited strong interparticle plasmonic coupling. This AuNP-mediated strategy offers new opportunities to drive macroscopic self-assembly and to fabricate well-defined nanophotonic materials and devices.

  18. The puzzling assembly of the Milky Way halo – contributions from dwarf Spheroidals and globular clusters

    Directory of Open Access Journals (Sweden)

    Lépine S.

    2012-02-01

    Full Text Available While recent sky surveys have uncovered large numbers of ever fainter Milky Way satellites, their classification as star clusters, low-luminosity galaxies, or tidal overdensities remains often unclear. Likewise, their contributions to the build-up of the halo is yet debated. In this contribution we will discuss the current knowledge of the stellar populations and chemo-dynamics in these puzzling satellites, with a particular focus on dwarf spheroidal galaxies and the globular clusters in the outer Galactic halo. Also the question of whether some of the outermost halo objects are dynamically associated with the (Milky Way halo at all is addressed in terms of proper measurements in the remote Leo I and II dwarf galaxies.

  19. On the puzzling feature of the silence of precursory electromagnetic emissions

    CERN Document Server

    Eftaxias, K; Chelidze, T

    2012-01-01

    It has been suggested that fracture induced MHz-kHz electromagnetic (EM) emissions, which emerge from a few days up to a few hours before the main seismic shock occurrence, in accordance with the laboratory experiments, permit a real time monitoring of damage process of last stages of earthquake preparation process, as it is happens at the laboratory scale. Despite fairly abundant evidence, EM precursors have not been adequately accepted as credible physical quantities. These negative views are enhanced by the fact that certain "puzzling features" are consistently observed in candidate pre-seismic EM emissions. More precisely, EM silence in all frequency bands appears before the main seismic shock occurrence, as well as during the aftershock period. Actually, the view that "acceptance of 'precursive' EM signals without convincing co-seismic signals should not be expected" seems to be reasonable. In this work we focus on this point. We examine whether the aforementioned features of EM silence are really puzzli...

  20. Simon`s Puzzle: Heuristics in the Process of Making Political Choices

    Directory of Open Access Journals (Sweden)

    Mateusz Wajzer

    2014-07-01

    Full Text Available In this article we analyse one of the most fascinating paradoxes of mass politics. Based on the data from the studies of neurobiologists, neurologists, social psychology, cognitive and evolution studies we answer the question specified in literature as the Simon’s puzzle: How is it possible that citizens have their opinions about politics, if they know so little about it? We began our analysis from the criticism of the economic rationality approach. To do this, we referred to the Allais paradox, cognitive dissonance theory, Ellsberg paradox, the concept of bounded rationality, conjunction fallacy and prospect theory. Next, we described the evolutionary processes shaping the minds of Homo sapiens and characterised cognitive mechanisms, thanks to which people can make political choices, especially in view of the shortage of time and information. The following heuristics are referred to herein: affect, recognition, judgment and imitation.

  1. Hyperon puzzle and the RMF model with scaled hadron masses and coupling constants

    Science.gov (United States)

    Kolomeitsev, E. E.; Maslov, K. A.; Voskresensky, D. N.

    2016-01-01

    The equation of state of cold baryonic matter is studied within a relativistic mean-field model with hadron masses and coupling constants depending on a scalar field. We demonstrate that if the effective nucleon mass stops to decrease with a density increase at densities n > n*> n0, where n0 is the nuclear saturation density, the equation of state stiffens for these densities and the limiting neutron star mass increases. The stabilization of the nucleon mass can be realised if in the equation of motion for the scalar mean-field there appear a term sharply varying in a narrow vicinity of the field value corresponding to the density n*. We show several possible realizations of this mechanism getting sufficiently stiff equations of state. The appearance of hyperons in dense neutron star interiors is accounted for. The obtained equations of state remain sufficiently stiff if the reduction of the ϕ meson mass is incorporated. Thereby, the hyperon puzzle can be resolved.

  2. Well-Defined Cyclic Triblock Terpolymers: A Missing Piece of the Morphology Puzzle

    KAUST Repository

    Polymeropoulos, George

    2016-10-27

    Two well-defined cyclic triblock terpolymers, missing pieces of the terpolymer morphology puzzle, consisting of poly(isoprene), polystyrene, and poly(2-vinylpyridine), were synthesized by combining the Glaser coupling reaction with anionic polymerization. An α,ω-dihydroxy linear triblock terpolymer (OH-PI1,4-b-PS-b-P2VP-OH) was first synthesized followed by transformation of the OH to alkyne groups by esterification with pentynoic acid and cyclization by Glaser coupling. The size exclusion chromatography (SEC) trace of the linear terpolymer precursor was shifted to lower elution time after cyclization, indicating the successful synthesis of the cyclic terpolymer. Additionally, the SEC trace of the cyclic terpolymer produced, after cleavage of the ester groups, shifted again practically to the position corresponding to the linear precursor. The first exploratory results on morphology showed the tremendous influence of the cyclic structure on the morphology of terpolymers. © 2016 American Chemical Society.

  3. Towards the resolution of the e+e- --> Nbar N puzzle

    CERN Document Server

    Karliner, M M

    2002-01-01

    We discuss the puzzling experimental results on baryon-antibaryon production in e+e- annihilation close to the threshold, in particular the fact that sigma(e+e- --> nbar n) is somewhat greater than sigma(e+e- --> pbar p). We discuss an interpretation in terms of a two-step process, via an intermediate coherent isovector state serving as an intermediary between e+e- and the baryon-antibaryon system. We provide evidence that the isovector channel dominates both e+e- --> pions and from Nbar N annihilation at rest, and show that the observed ratio of sigma(e+e- --> nbar n)/sigma(e+e- --> pbar p) can be understood quantitatively in this picture.

  4. Maximal neutron star mass and the resolution of hyperon puzzle in modified gravity

    CERN Document Server

    Astashenok, Artyom V; Odintsov, Sergei D

    2014-01-01

    The so-called hyperon puzzle in the theory of neutron stars is considered in the framework of modified $f(R)$ gravity. We show that for simple hyperon equations of state, it is possible to obtain the maximal neutron star mass which satisfies the recent observational data for PSR J1614-2230, in higher-derivative models with power-law terms as $f(R) = R+\\alpha R^2+ \\beta R^3$. The soft hyperon equation of state under consideration is usually treated as non-realistic in the standard General Relativity. The numerical analysis of Mass-Radius relation for massive neutron stars with hyperon equation of state in modified gravity turns out to be consistent with observations. Thus, we show that the same modified gravity can solve at once three problems: consistent description of the maximal mass of neutron star, realistic Mass-Radius relation and account for hyperons in equation of state.

  5. A Theoretical Model of Jigsaw-Puzzle Pattern Formation by Plant Leaf Epidermal Cells.

    Science.gov (United States)

    Higaki, Takumi; Kutsuna, Natsumaro; Akita, Kae; Takigawa-Imamura, Hisako; Yoshimura, Kenji; Miura, Takashi

    2016-04-01

    Plant leaf epidermal cells exhibit a jigsaw puzzle-like pattern that is generated by interdigitation of the cell wall during leaf development. The contribution of two ROP GTPases, ROP2 and ROP6, to the cytoskeletal dynamics that regulate epidermal cell wall interdigitation has already been examined; however, how interactions between these molecules result in pattern formation remains to be elucidated. Here, we propose a simple interface equation model that incorporates both the cell wall remodeling activity of ROP GTPases and the diffusible signaling molecules by which they are regulated. This model successfully reproduces pattern formation observed in vivo, and explains the counterintuitive experimental results of decreased cellulose production and increased thickness. Our model also reproduces the dynamics of three-way cell wall junctions. Therefore, this model provides a possible mechanism for cell wall interdigitation formation in vivo.

  6. PENGARUH PEMBELAJARAN TEAM GAMES TOURNAMENT BERBANTUAN CROSSWORD PUZZLE TERHADAP HASIL BELAJAR

    Directory of Open Access Journals (Sweden)

    Sopiyatun Munawaroh

    2016-05-01

    Full Text Available Jenis penelitian yang digunakan adalah penelitian eksperimen. Penelitian ini bertujuan untuk mengetahui pengaruh pembelajaran Team Games Tournament (TGT berbantuan media crossword puzzle terhadap hasil belajar dan mengetahui tanggapan siswa. Populasi pada penelitian ini adalah seluruh siswa kelas X MIA. Pengambilan sampel secara cluster random sampling yaitu kelas X MIA 2 sebagai kelas kontrol dan X MIA 3 sebagai kelas eksperimen. Berdasarkan hasil uji peerbedaan dua rata-rata hasil belajar yang diperoleh kelas eksperimen 54,73-78,06 dan kelas kontrol 49,65-72,06. Sedangkan uji ketuntasan hasil belajar kelas eksperimen mencapai 87,10% dan kelas kontrol 40,54%. Berdasarkan hasil uji peningkatan hasil belajar kelas eksperimen mencapai 16,30 dan kelas kontrol 12,80. Adapun hasil observasi terhadap aspek sikap diperoleh nilai rata-rata kelas eksperimen 84,21 dan kelas kontrol 82,08. Sedangkan untuk hasil observasi terhadap aspek keterampilan diperoleh rata-rata nilai siswa kelas eksperimen 79,66 dan kelas kontrol 72,70. Berdasarkan hasil angket tanggapan siswa, model pembelajaran Team Games Tournament memperoleh tanggapan positif yaitu siswa merasa senang dan dapat meningkatkan pemahaman pada materi tata nama senyawa. Simpulan dari penelitian ini yaitu model pembelajaran tipe Team Games Tournament berbantuan media crossword puzzle berpengaruh signifikan terhadap hasil belajar dan mendapat tanggapan positif dari siswa.This research is experimental research. This study aims to determine the effect of learning Team Games Tournament (TGT media-aided crossword puzzle on learning outcomes and determine responses that students. The population in this study were all students of X MIA class. The sampling is a cluster random sampling, they are the X MIA 2 class as a control class and X MIA 3 class as the experimental. Based on the test, the results of the difference of two average are 54.73-78.06 for the experimental class and 49.65-72.06 for the control

  7. OLD PUZZLE, NEW INSIGHTS: A LITHIUM-RICH GIANT QUIETLY BURNING HELIUM IN ITS CORE

    Energy Technology Data Exchange (ETDEWEB)

    Aguirre, V. Silva; Christensen-Dalsgaard, J.; Jessen-Hansen, J. [Stellar Astrophysics Centre, Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, DK-8000 Aarhus C (Denmark); Ruchti, G. R. [Lund Observatory, Department of Astronomy and Theoretical Physics, Box 43, SE-221 00 Lund (Sweden); Hekker, S. [Max-Planck-Institut für Sonnensystemforschung, Justus-von-Liebig-Weg 3, D-37077 Göttingen (Germany); Cassisi, S. [INAF-Astronomical Observatory of Teramo, Via M. Maggini sn, I-64100 Teramo (Italy); Datta, A. [Department of Physics and Meteorology, Indian Institute of Technology, Kharagpur 721302 (India); Jendreieck, A. [Max-Planck-Institut für Astrophysics, Karl Schwarzschild Strasse 1, D-85748 Garching (Germany); Mazumdar, A. [Homi Bhabha Centre for Science Education, TIFR, V. N. Purav Marg, Mankhurd, Mumbai 400088 (India); Mosser, B. [LESIA Observatoire de Paris, CNRS, Université Pierre et Marie Curie, Université Denis Diderot, F-92195 Meudon Cedex (France); Stello, D. [Sydney Institute for Astronomy, School of Physics, University of Sydney, NSW 2006 (Australia); Beck, P. G.; De Ridder, J. [Instituut voor Sterrenkunde, KU Leuven, Celestijnenlaan 200D, B-3001 Leuven (Belgium)

    2014-03-20

    About 1% of giant stars have been shown to have large surface Li abundances, which is unexpected according to standard stellar evolution models. Several scenarios for lithium production have been proposed, but it is still unclear why these Li-rich giants exist. A missing piece in this puzzle is the knowledge of the exact stage of evolution of these stars. Using low- and-high-resolution spectroscopic observations, we have undertaken a survey of lithium-rich giants in the Kepler field. In this Letter, we report the finding of the first confirmed Li-rich core-helium-burning giant, as revealed by asteroseismic analysis. The evolutionary timescales constrained by its mass suggest that Li production most likely took place through non-canonical mixing at the RGB tip, possibly during the helium flash.

  8. Completing the nuclear reaction puzzle of the nucleosynthesis of 92Mo

    CERN Document Server

    Tveten, G M; Schwengner, R; Naqvi, F; Larsen, A C; Eriksen, T K; Garrote, F L Bello; Bernstein, L A; Bleuel, D L; Campo, L Crespo; Guttormsen, M; Giacoppo, F; Görgen, A; Hagen, T W; Hadynska-Klek, K; Klintefjord, M; Meyer, B S; Nyhus, H T; Renstrøm, T; Rose, S J; Sahin, E; Siem, S; Tornyi, T G

    2016-01-01

    One of the greatest questions for modern physics to address is how elements heavier than iron are created in extreme, astrophysical environments. A particularly challenging part of that question is the creation of the so-called p-nuclei, which are believed to be mainly produced in some types of supernovae. The lack of needed nuclear data presents an obstacle in nailing down the precise site and astrophysical conditions. In this work, we present for the first time measurements on the nuclear level density and average strength function of $^{92}$Mo. State-of-the-art p-process calculations systematically underestimate the observed solar abundance of this isotope. Our data provide stringent constraints on the $^{91}$Nb$(p,{\\gamma})^{92}$Mo reaction rate, which is the last unmeasured reaction in the nucleosynthesis puzzle of $^{92}$Mo. Based on our results, we conclude that the $^{92}$Mo abundance anomaly is not due to the nuclear physics input to astrophysical model calculations.

  9. From inflation to dark energy through a dynamical Lambda: an attempt at alleviating fundamental cosmic puzzles

    CERN Document Server

    Basilakos, S; Solà, J

    2013-01-01

    After decades of successful hot big-bang paradigm, Cosmology still lacks a framework in which the early inflationary phase of the universe smoothly matches the radiation epoch and evolves to the present `quasi' de Sitter spacetime. No less intriguing is that the current value of the effective vacuum energy density is vastly smaller than the value that triggered inflation. In this Essay we propose a new class of cosmologies capable of overcoming, or highly alleviating, some of these acute cosmic puzzles. Powered by a decaying vacuum energy density, the spacetime emerges from a pure nonsingular de Sitter vacuum stage, "gracefully" exits from inflation to a radiation phase followed by dark matter and vacuum regimes, and, finally, evolves to a late time de Sitter phase.

  10. Anomalies in psi(2S) decay and the rho-pi puzzle

    CERN Document Server

    Suzuki, M

    2000-01-01

    We examine the so-called rho-pi puzzle of the psi(2S) decay by incorporating two inputs: One is the relative phase between the one-photon and the gluon decay amplitude, and the other is a possible anomaly in the inclusive nonelectromagnetic decay rate of psi(2S). We propose the possibility that in the psi(2S) decay a hadronic decay process of long distance origin is important in addition to the short-distance decay process. The amplitude of this additional process should nearly cancel the three-gluon amplitude in the exclusive psi(2S)---> 1-0- and turn the sum dominantly real in contrast to the J/psi decay. We present general consequences of this mechanism and then briefly look into two models which possibly explain the course of this additional amplitude.

  11. Puzzles in modern biology. III.Two kinds of causality in age-related disease

    Science.gov (United States)

    Frank, Steven A.

    2017-01-01

    The two primary causal dimensions of age-related disease are rate and function. Change in rate of disease development shifts the age of onset. Change in physiological function provides necessary steps in disease progression. A causal factor may alter the rate of physiological change, but that causal factor itself may have no direct physiological role. Alternatively, a causal factor may provide a necessary physiological function, but that causal factor itself may not alter the rate of disease onset. The rate-function duality provides the basis for solving puzzles of age-related disease. Causal factors of cancer illustrate the duality between rate processes of discovery, such as somatic mutation, and necessary physiological functions, such as invasive penetration across tissue barriers. Examples from cancer suggest general principles of age-related disease.

  12. Old puzzle, new insights: a lithium rich giant quietly burning helium in its core

    CERN Document Server

    Aguirre, V Silva; Hekker, S; Cassisi, S; Christensen-Dalsgaard, J; Datta, A; Jendreieck, A; Jessen-Hansen, J; Mazumdar, A; Mosser, B; Stello, D; Beck, P G; de Ridder, J

    2014-01-01

    About 1% of giant stars have been shown to have large surface Li abundances, which is unexpected according to standard stellar evolution models. Several scenarios for lithium production have been proposed, but it is still unclear why these Li-rich giants exist. A missing piece in this puzzle is the knowledge of the exact stage of evolution of these stars. Using low-and-high-resolution spectroscopic observations, we have undertaken a survey of lithium-rich giants in the Kepler field. In this letter, we report the finding of the first confirmed Li-rich core-helium-burning giant, as revealed by asteroseismic analysis. The evolutionary timescales constrained by its mass suggest that Li-production most likely took place through non-canonical mixing at the RGB-tip, possibly during the helium flash.

  13. Completing the nuclear reaction puzzle of the nucleosynthesis of 92Mo

    Science.gov (United States)

    Tveten, G. M.; Spyrou, A.; Schwengner, R.; Naqvi, F.; Larsen, A. C.; Eriksen, T. K.; Bello Garrote, F. L.; Bernstein, L. A.; Bleuel, D. L.; Crespo Campo, L.; Guttormsen, M.; Giacoppo, F.; Görgen, A.; Hagen, T. W.; Hadynska-Klek, K.; Klintefjord, M.; Meyer, B. S.; Nyhus, H. T.; Renstrøm, T.; Rose, S. J.; Sahin, E.; Siem, S.; Tornyi, T. G.

    2016-08-01

    One of the greatest questions for modern physics to address is how elements heavier than iron are created in extreme astrophysical environments. A particularly challenging part of that question is the creation of the so-called p -nuclei, which are believed to be mainly produced in some types of supernovae. The lack of needed nuclear data presents an obstacle in nailing down the precise site and astrophysical conditions. In this work, we present for the first time measurements on the nuclear level density and average γ strength function of 92Mo. State-of-the-art p -process calculations systematically underestimate the observed solar abundance of this isotope. Our data provide stringent constraints on the 91Nb(p ,γ )92Mo reaction rate, which is the last unmeasured reaction in the nucleosynthesis puzzle of 92Mo. Based on our results, we conclude that the 92Mo abundance anomaly is not due to the nuclear physics input to astrophysical model calculations.

  14. Desain Pembelajaran Bangun Datar Menggunakan Fable “Dog Catches Cat” And Puzzle Tangram Di Kelas II SD

    Directory of Open Access Journals (Sweden)

    Lisnani Lisnani

    2013-06-01

    Full Text Available Tujuan penelitian ini adalah mengembangkan kemampuan berpikir kreatif matematis siswa dalam pengenalan dan pengelompokkan bangun datar melalui fable “dog catches cat”, puzzle tangram, dan kreasi origami. Metode yang digunakan adalah design research terdiri dari tiga tahap, yaitu: preliminary, design experiment (pilot experiment dan teaching experiment, dan analysis retrospective.  Penelitian ini mengembangkan hasil pembelajaran tentang bangun datar melalui serangkaian aktivitas, prosedur, dan strategi bagi siswa dalam menemukan kemampuan berpikir kreatif melalui Pendekatan Pendidikan Matematika Realistik Indonesia (PMRI melalui konteks tangram melalui fable “dog catches cat”. Puzzle tangram, dan kreasi origami menjadi starting point materi pengenalan dan pengelompokkan bangun datar. Hasil dari penelitian ini berupa learning trajectory pada masing-masing aktivitas yaitu: 1 Aktivitas 1, siswa mengenal berbagai bentuk bangun datar melalui penggunaan fable. 2 Aktivitas 2, siswa mampu menyebutkan dan mengelompokkan berbagai bangun datar melalui puzzle tangram. 3 Aktivitas 3, membentuk dan mengelompokkan bangun datar dan terbentuk suatu kreasi baru berupa kucing, anjing, dan lainnya.The purpose of this research is to develop mathematical creative thinking abilities and grouping students in the introduction of a flat wake through the fable “dog catches paint " , tangram puzzles, and origami creations. The method used is the research design consists of three stages: preliminary, design of experiments (pilot experiments and teaching experiments, and a retrospective analysis. This study develops learning outcomes on a flat wake through a series of activities, procedures, and strategies for students in finding creative thinking abilities through Realistic Mathematics Education Approach Indonesia (PMRI through tangram context through fable “dog catches the paint “. Tangram puzzles, and origami creations become the starting point and the

  15. Two approaches towards the flavour puzzle. Dynamical minimal flavour violation and warped extra dimensions

    Energy Technology Data Exchange (ETDEWEB)

    Albrecht, Michaela E.

    2010-08-16

    The minimal-flavour-violating (MFV) hypothesis considers the Standard Model (SM) Yukawa matrices as the only source of flavour violation. In this work, we promote their entries to dynamical scalar spurion fields, using an effective field theory approach, such that the maximal flavour symmetry (FS) of the SM gauge sector is formally restored at high energy scales. The non-vanishing vacuum expectation values of the spurions induce a sequence of FS breaking and generate the observed hierarchy in the SM quark masses and mixings. The fact that there exists no explanation for it in the SM is known as the flavour puzzle. Gauging the non-abelian subgroup of the spontaneously broken FS, we interpret the associated Goldstone bosons as the longitudinal degrees of freedom of the corresponding massive gauge bosons. Integrating out the heavy Higgs modes in the Yukawa spurions leads directly to flavour-changing neutral currents (FCNCs) at tree level. The coefficients of the effective four-quark operators, resulting from the exchange of heavy flavoured gauge bosons, strictly follow the MFV principle. On the other hand, the Goldstone bosons associated with the global abelian symmetry group behave as weakly coupled axions which can be used to solve the strong CP problem within a modified Peccei-Quinn formalism. Models with a warped fifth dimension contain five-dimensional (5D) fermion bulk mass matrices in addition to their 5D Yukawa matrices, which thus represent an additional source of flavour violation beyond MFV. They can address the flavour puzzle since their eigenvalues allow for a different localisation of the fermion zero mode profiles along the extra dimension which leads to a hierarchy in the effective four-dimensional (4D) Yukawa matrices. At the same time, the fermion splitting introduces non-universal fermion couplings to Kaluza-Klein (KK) gauge boson modes, inducing tree-level FCNCs. Within a Randall-Sundrum model with custodial protection (RSc model) we carefully work

  16. Biophysical Puzzles Concerning Magnetite-Based Magnetoreception in the Common Nematode, Caenorhabditis elegans.

    Science.gov (United States)

    Kirschvink, J. L.; Kobayashi, A. K.

    2015-12-01

    A recent report demonstrating magnetotactic behavior in the nematode worm, C. elegans, presents two intriguing biophysical puzzles. Vidal-Gadea et al. (2015, DOI: 10.7554/eLife.07493) show that wild-type, well-fed populations from both Hemispheres migrate upwards when their soil environment is moist and wet, and downward when starved. Their data show that inverting the vertical component of the magnetic field reverses the migration direction, indicating that it is a magnetically polar (not axial) response. Also, the angle of magnetic migration varies with the inclination angle of the local geomagnetic field at the native site, minimizing travel time. This ancestral magnetic migration direction persists even when strains are taken to different areas. We note that only a single-domain ferromagnetic magnetoreceptor (e.g, magnetite) is capable of producing a polar magnetotactic response, and in support there is one report of magnetosomes in C. elegans (Cranfield et al., 2004;DOI 10.1098/rsbl.2004.0209). However, the polarity of a magnetosome is determined at the time it grows across the SPM/SD threshold, and the magnetic orientation will lock-in randomly unless biased by the strong field of adjacent magnetosomes. Hence, the persistence of a North or South seeking direction preference within these populations demands that stable magnetosome chains of fixed polarity must be transmitted from parents, to the eggs, to the larvae, and then to the new adults. This is similar to the non-genetic inheritance process by which populations of magnetotactic bacteria can maintain North- or South-seeking swimming preference. Furthermore, for a magnetotactic organism to maintain a consistent angle from the magnetic axis is not enough to make it go vertical; it would go in a cone. For them to go vertical as reported (or to deviate at their natal magnetic inclination) demands that they must have a separate gravity sensor with which to measure the inclination angle relative to the

  17. Putting the whole grain puzzle together: health benefits associated with whole grains--summary of American Society for Nutrition 2010 Satellite Symposium

    National Research Council Canada - National Science Library

    Jonnalagadda, Satya S; Harnack, Lisa; Liu, Rui Hai; McKeown, Nicola; Seal, Chris; Liu, Simin; Fahey, George C

    2011-01-01

    The symposium "Putting the Whole Grain Puzzle Together: Health Benefits Associated with Whole Grains" sponsored by the ASN brought together researchers to review the evidence regarding the health benefits associated with whole grains...

  18. Cles: Etes-vous bon detective?; Enigmes grammaticales; Problemes policiers; Kidnapping (Keys: Are You a Good Detective?; Grammatical Puzzles; Detective Mysteries; Kidnapping).

    Science.gov (United States)

    Debyser, Francis; And Others

    1984-01-01

    Four sets of French classroom activities are presented: a mystery whose clues include two postcard messages; three puzzles with grammar-related clues; a mystery contained in three comic strip frames; and the solving of a kidnapping mystery. (MSE)

  19. Marriage \\`a-la-MOND: Baryonic dark matter in galaxy clusters and the cooling flow puzzle

    CERN Document Server

    Milgrom, Mordehai

    2007-01-01

    I start with a brief introduction to MOND phenomenology and its possible roots in cosmology--a notion that may turn out to be the most far reaching aspect of MOND. Next I discuss the implications of MOND for the dark matter (DM) doctrine: MOND's successes imply that baryons determine everything. For DM this would mean that the puny tail of leftover baryons in galaxies wags the hefty DM dog. This has to occur in many intricate ways, and despite the haphazard construction history of galaxies--a very tall order. I then concentrate on galaxy clusters in light of MOND, which still requires some yet undetected cluster dark matter, presumably in some baryonic form (CBDM). This CBDM might contribute to the heating of the x-ray emitting gas and thus alleviate the cooling-flow puzzle. MOND, qua theory of dynamics, does not directly enter the microphysics of the gas; however, it does force a new outlook on the role of DM in shaping the cluster gasdynamics: MOND tells us that the cluster DM is not cold dark matter, is no...

  20. WHY CATS LAND ON THEIR FEET: AND 76 OTHER PHYSICAL PARADOXES AND PUZZLES

    Directory of Open Access Journals (Sweden)

    Pedro Zany Caldeira

    Full Text Available Em Why Cats Land On Their Feet: And 76 Other Physical Paradoxes and Puzzles, Mark Levi, professor de matemática na Pennsylvania State University e autor do livro The Mathematical Mechanic: Using Phisical Reasoning to Solve Problems(publicado pela mesma editora, apresenta 77 paradoxos e enigmas da Física (que de fato correspondem a mais de uma centena de problemas, seguindo uma estrutura simples de exploração de cada um deles: Problema / Questão, (Pista, Resposta e Explicação (por vezes mais de uma. Como o próprio autor afirma, "um bom paradoxo físico é (1 uma surpresa, (2 um enigma e (3 uma lição, tudo embrulhado num pacote divertido. Um paradoxo em muitas ocasiões apresenta um argumento muito convincente que conduz a uma conclusão errada que parece certa, ou a uma conclusão certa que parece errada ou surpreendente" (p. 1. E os paradoxos e enigmas não são apenas divertidos, eles também treinam a intuição, a lógica e o pensamento crítico (seja qual for a área de estudo ou ensino.

  1. Learning and Memory Processes Following Cochlear Implantation:The Missing Piece of the Puzzle

    Directory of Open Access Journals (Sweden)

    David B. Pisoni

    2016-04-01

    Full Text Available At the present time, there is no question that cochlear implants work and often work very well in quiet listening conditions for many profoundly deaf children and adults. The speech and language outcomes data published over the last two decades document quite extensively the clinically significant benefits of cochlear implants. Although there now is a large body of evidence supporting the efficacy of cochlear implants as a medical intervention for profound hearing loss in both children and adults, there still remain a number of challenging unresolved clinical and theoretical issues that deal with the effectiveness of cochlear implants in individual patients that have not yet been successfully resolved. In this paper, we review recent findings on learning and memory, two central topics in the field of cognition that have been seriously neglected in research on cochlear implants. Our research findings on sequence learning, memory and organization processes, and retrieval strategies used in verbal learning and memory of categorized word lists suggests that basic domain-general learning abilities may be the missing piece of the puzzle in terms of understanding the cognitive factors that underlie the enormous individual differences and variability routinely observed in speech and language outcomes following cochlear implantation.

  2. Theory of mind: a new perspective on the puzzle of belief ascription.

    Science.gov (United States)

    Airenti, Gabriella

    2015-01-01

    The concept of theory of mind (ToM) has considerably changed since its first proposal. The aim of first human studies was to understand how young children acquire the representation of others' mental states, in particular beliefs, and how they distinguish them from their own and from reality. The False Belief Task was designed to prove the acquisition of this capacity. According to children's performance in this test the acquisition of ToM has been attested at around 4 years of age. In last years it has been shown that using spontaneous response tasks also 15-month-old-children could attribute to an agent a false belief about the location of an object. These results have generated the puzzle of belief-ascription: Why do 3-year-old children fail the classical false belief tasks whereas much younger children show the correct expectation in the spontaneous response tasks? In this paper I shall argue that (i) infants and young children, when confronted with the two forms of false belief tasks do not face the same problem and (ii) behind the two testing situations there are different ways to understand theory of mind. I shall propose that what appears in infants is the natural human disposition to intersubjectivity.

  3. The puzzling dynamical status of the core of the globular cluster NGC 6752

    CERN Document Server

    Ferraro, F R; Sabbi, E; Lagani, P; Rood, R T; D'Amico, N; Origlia, L

    2003-01-01

    We have used high resolution WFPC2-HST and ground based Wide Field images to determine the center of gravity and construct an extended radial density and brightness profile of the cluster NGC 6752 including, for the first time, detailed star counts in the very inner region. The barycenter of the 9 innermost X-ray sources detected by Chandra is located only 1.9" off the new center of gravity. Both the density and the brightness profile of the central region are best fitted by a double King model, suggesting that NGC 6752 is experiencing a post-core collapse "bounce". Taking advantage from our new optical data, we discuss the puzzling nature of the accelerations displayed by the innermost millisecond pulsars detected in this cluster. We discuss two possible origins to the accelerations: 1) the overall cluster gravitational potential which would require a central projected mass to light ratio of order 6-7 and the existence of a few thousand solar masses of low-luminosity matter within the inner 0.08 pc of NGC675...

  4. Geneva University - Measurement of the Lamb shift in muonic hydrogen: the proton radius puzzle

    CERN Multimedia

    2010-01-01

    GENEVA UNIVERSITY École de physique Département de physique nucléaire et corspusculaire 24, quai Ernest-Ansermet 1211 GENEVA 4 Tel: (022) 379 62 73 Fax: (022) 379 69 92 Wednesday 12 May 2010 PARTICLE PHYSICS SEMINAR at 17.00 hrs – Stückelberg Auditorium Measurement of the Lamb shift in muonic hydrogen: the proton radius puzzle Dr Aldo Antogninia , CREMA Collaboration, Max Planck Institute, Germany At the Paul Scherrer Institut, Switzerland, we have measured several 2S-2P transition frequencies in muonic hydrogen (µp) and deuterium (µd) by means of laser spectroscopy. This results in an order of magnitude improvement on the rms charge radius values of the proton and the deuteron. Additionally the Zemach radii and the deuteron polarizability are also inferred. The new proton radius value is deduced with a relative accuracy of 0.1% but strongly disagrees from CODATA. The origin of this discrepancy is not yet known. It may come from theo...

  5. Re-engaging cross-reactive memory B Cells: The influenza puzzle

    Directory of Open Access Journals (Sweden)

    Ali H. eEllebedy

    2012-03-01

    Full Text Available The emergence of a novel influenza A virus strain into humans poses a continuous public health threat. Vaccination is the most effective means of protection against influenza. The generation of memory B cells and long-lived plasma cells (PCs that can maintain protective levels of influenza-specific antibodies for protracted periods of time is the foundation for the success of such vaccines. Influenza vaccines elicit an antibody response that is primarily targeting viral surface glycoproteins. However, frequent amino acid mutations within the immunodominant epitopes allow the virus to efficiently escape neutralization by pre-existing antibodies and consequently cause annual epidemics and occasional pandemics. Recently, monoclonal antibodies (mAbs that target subdominant influenza epitopes have been extensively characterized. These epitopes are immunogenic, can mediate virus neutralization, and most importantly are conserved among different influenza strains. It remains puzzling, however, that despite being repeatedly exposed to such conserved domains of influenza HA either in the form of vaccination or natural infection, most humans do not develop immunological memory that can provide broad protection against emerging virus strains. Here we will discuss the conditions that may be required for engaging such cross-reactive memory B cells in the immune response to influenza infection and vaccination in humans.

  6. Puzzles in modern biology. IV. Neurodegeneration, localized origin and widespread decay [version 1; referees: 2 approved

    Directory of Open Access Journals (Sweden)

    Steven A. Frank

    2016-10-01

    Full Text Available The motor neuron disease amyotrophic lateral sclerosis (ALS typically begins with localized muscle weakness. Progressive, widespread paralysis often follows over a few years. Does the disease begin with local changes in a small piece of neural tissue and then spread? Or does neural decay happen independently across diverse spatial locations? The distinction matters, because local initiation may arise by local changes in a tissue microenvironment, by somatic mutation, or by various epigenetic or regulatory fluctuations in a few cells. A local trigger must be coupled with a mechanism for spread. By contrast, independent decay across spatial locations cannot begin by a local change, but must depend on some global predisposition or spatially distributed change that leads to approximately synchronous decay. This article outlines the conceptual frame by which one contrasts local triggers and spread versus parallel spatially distributed decay. Various neurodegenerative diseases differ in their mechanistic details, but all can usefully be understood as falling along a continuum of interacting local and global processes. Cancer provides an example of disease progression by local triggers and spatial spread, setting a conceptual basis for clarifying puzzles in neurodegeneration. Heart disease also has crucial interactions between global processes, such as circulating lipid levels, and local processes in the development of atherosclerotic plaques. The distinction between local and global processes helps to understand these various age-related diseases.

  7. Y and ψ leptonic decays as probes of solutions to the R( D (*)) puzzle

    Science.gov (United States)

    Aloni, Daniel; Efrati, Aielet; Grossman, Yuval; Nir, Yosef

    2017-06-01

    Experimental measurements of the ratios R({D}^{(\\ast )})\\equiv Γ (B\\to {D}^{(*)}τ v)/Γ (B\\to {D^{(*)}ℓ v)}(ℓ =e,μ ) show a 3 .9 σ deviation from the Standard Model prediction. In the absence of light right-handed neutrinos, a new physics contribution to b → cτν decays necessarily modifies also b\\overline{b}\\to {τ}+{τ}- and/or c\\overline{c}\\to {τ}+{τ}- transitions. These contributions lead to violation of lepton flavor universality in, respectively, Y and ψ leptonic decays. We analyze the constraints resulting from measurements of the leptonic vector-meson decays on solutions to the R( D (*)) puzzle. Available data from BaBar and Belle can already disfavor some of the new physics explanations of this anomaly. Further discrimination can be made by measuring Y(1 S, 2 S, 3 S) → ττ in the upcoming Belle II experiment.

  8. Low-voltage puzzle-like fractal microelectromechanial system variable capacitor suppressing pull-in

    KAUST Repository

    Elshurafa, Amro M.

    2012-10-01

    This Letter introduces an electrostatically actuated fractal MEMS variable capacitor that, by utilising the substrate, extends the tuning range (TR) beyond the theoretical limit of 1.5 as dictated by the pull-in phenomenon. The backbone concept behind the fractal varactor is to create a suspended movable plate possessing a specific fractal geometry, and to simultaneously create a bottom fixed plate complementary in shape to the top plate. Thus, when the top plate is actuated, it moves towards the bottom plate and fills the void present within the bottom plate without touching it akin to how puzzle pieces are assembled. Further, a reasonable horizontal separation is maintained between both the plates to avoid shorting. The electrostatic forces come from the capacitance formed between the top plate and bottom plate, and from the capacitance formed between the top plate and the doped substrate. The variable capacitor was fabricated in the PolyMUMPS process and provided a TR of 4.1 at 6 V, and its resonant frequency was in excess of 40 GHz.

  9. Hyperon puzzle and the RMF model with scaled hadron masses and coupling constants

    CERN Document Server

    Kolomeitsev, E E; Voskresensky, D N

    2015-01-01

    The equation of state of cold baryonic matter is studied within a relativistic mean-field model with hadron masses and coupling constants depending on a scalar field. We demonstrate that if the effective nucleon mass stops to decrease with a density increase at densities $n>n_*>n_0$, where $n_0$ is the nuclear saturation density, the equation of state stiffens for these densities and the limiting neutron star mass increases. The stabilization of the nucleon mass can be realised if in the equation of motion for the scalar mean-field there appear a term sharply varying in a narrow vicinity of the field value corresponding to the density $n_*$. We show several possible realizations of this mechanism getting sufficiently stiff equations of state. The appearance of hyperons in dense neutron star interiors is accounted for. The obtained equations of state remain sufficiently stiff if the reduction of the $\\phi$ meson mass is incorporated. Thereby, the hyperon puzzle can be resolved.

  10. Gravity does not exist a puzzle for the 21st century

    CERN Document Server

    Icke, Vincent

    2014-01-01

    Every scientific fact begins as an opinion about the unknown—a theory—that becomes fact as evidence piles up to support it. But what if two theories exist that correspond perfectly to observed phenomena and they cannot be reconciled with each other? Can theory become fact? Such is the dilemma in contemporary physics. In seeking to understand the mechanisms of the universe, physicists have arrived at two conflicting theories: one explains the mystery of gravity through a precise model of space and time, and the other explains the mystery of matter via the behavior of quantum particles. Each theory reigns in its own domain. But 13.8 billion years ago, when the universe first came into being, gravity and matter belonged to a single realm. Can these theories be united, and if so, what facts will be revealed? This, contends Vincent Icke, is the central puzzle facing physics in our century. Combining Icke’s expertise with a robust argument and intellectual playfulness, Gravity Does Not Exist makes a notorious...

  11. A Low-Resolution Spectroscopic Exploration of Puzzling OGLE Variable Stars

    CERN Document Server

    Pietrukowicz, P; Angeloni, R; di Mille, F; Soszynski, I; Udalski, A; Germana, C

    2015-01-01

    We present the results of a spectroscopic follow-up of various puzzling variable objects detected in the OGLE-III Galactic disk and bulge fields. The sample includes mainly short-period multi-mode pulsating stars that could not have been unambiguously classified as either delta Sct or beta Cep type stars based on photometric data only, also stars with irregular fluctuations mimicking cataclysmic variables and stars with dusty shells, and periodic variables displaying brightenings in their light curves that last for more than half of the period. The obtained low-resolution spectra show that all observed short-period pulsators are of delta Sct type, the stars with irregular fluctuations are young stellar objects, and the objects with regular brightenings are A type stars or very likely Ap stars with strong magnetic field responsible for the presence of bright caps around magnetic poles on their surface. We also took spectra of objects designated OGLE-GD-DSCT-0058 and OGLE-GD-CEP-0013. An estimated effective tem...

  12. The Puzzling Li-rich Red Giant Associated with NGC 6819

    CERN Document Server

    Carlberg, Joleen K; Cunha, Katia; Majewski, Steven R; Meszaros, Szabolcs; Shetrone, Matthew; Prieto, Carlos Allende; Bizyaev, Dmitry; Stassun, Keivan G; Fleming, Scott W; Zasowski, Gail; Hearty, Fred; Nidever, David L; Schneider, Donald P; Holtzman, Jon A; Frinchaboy, Peter M

    2015-01-01

    A Li-rich red giant star (2M19411367+4003382) recently discovered in the direction of NGC 6819 belongs to the rare subset of Li-rich stars that have not yet evolved to the luminosity bump, an evolutionary stage where models predict Li can be replenished. The currently favored model to explain Li enhancement in first-ascent red giants like 2M19411367+4003382 requires deep mixing into the stellar interior. Testing this model requires a measurement of 12C/13C, which is possible to obtain from APOGEE spectra. However, the Li-rich star also has abnormal asteroseismic properties that call into question its membership in the cluster, even though its radial velocity and location on color-magnitude diagrams are consistent with membership. To address these puzzles, we have measured a wide array of abundances in the Li-rich star and three comparison stars using spectra taken as part of the APOGEE survey to determine the degree of stellar mixing, address the question of membership, and measure the surface gravity. We con...

  13. The Puzzling Origin of the Acquaintance between Charlotte Lennox and Thomas Birch

    Directory of Open Access Journals (Sweden)

    Patricia L. Hamilton

    2015-03-01

    Full Text Available Scholars have puzzled over the origin of the relationship between Charlotte Lennox and Thomas Birch. That the two shared a cordial professional relationship in 1759 is not surprising, but it is unclear how and when Birch obtained the poem "The Dream, an ode by Miss Ramsey of 15" (ca. 1744-45 for his manuscript collection. Possibly Edward Cave, publisher of The Gentleman’s Magazine, or other professional associates such as Samuel Johnson or Samuel Richardson supplied it. But archival evidence indicates that Lady Isabella Finch, Lennox’s earliest patroness, was in contact with Birch in 1749, raising the question of whether she could have given Birch the poem. However, a different type of connection between Lennox and Birch is suggested by Lennox’s first novel, The Life of Harriot Stuart, written by Herself (1750, which mentions William Chillingworth, Isaac Barrow, and John Tillotson as theological influences. Lennox may have known of these three seventeenth-century divines through Birch’s biographical work on them.

  14. Solving the 56Ni puzzle of magnetar-powered broad-lined type Ic supernovae

    CERN Document Server

    Wang, Ling-Jun; Xu, Dong; Wang, Shan-Qin; Dai, Zi-Gao; Wu, Xue-Feng; Wei, Jian-Yan

    2016-01-01

    Broad-lined type Ic supernovae (SNe Ic-BL) are of great importance because their association with long-duration gamma-ray bursts (LGRBs) holds the key to deciphering the central engine of LGRBs, which refrains from being unveiled despite decades of investigation. Among the two popularly hypothesized types of central engine, i.e., black holes and strongly magnetized neutron stars (magnetars), there is mounting evidence that the central engine of GRB-associated SNe (GRB-SNe) is rapidly rotating magnetars. Theoretical analysis also suggests that magnetars could be the central engine of SNe Ic-BL. What puzzled the researchers is the fact that light curve modeling indicates that as much as 0.2-0.5 solar mass of 56Ni was synthesized during the explosion of the SNe Ic-BL, which is unfortunately in direct conflict with current state-of-the-art understanding of magnetar-powered 56Ni synthesis. Here we propose a dynamic model of magnetar-powered SNe to take into account the acceleration of the ejecta by the magnetar, a...

  15. Simultaneous Explanation of the $R_K$ and $R_{D^{(*)}}$ Puzzles: a Model Analysis

    CERN Document Server

    Bhattacharya, Bhubanjyoti; Guévin, Jean-Pascal; London, David; Watanabe, Ryoutaro

    2016-01-01

    $R_K$ and $R_{D^{(*)}}$ are two $B$-decay measurements that presently exhibit discrepancies with the SM. Recently, using an effective field theory approach, it was demonstrated that a new-physics model can simultaneously explain both the $R_K$ and $R_{D^{(*)}}$ puzzles. There are two UV completions that can give rise to the effective Lagrangian: (i) $VB$: a vector boson that transforms as an $SU(2)_L$ triplet, as in the SM, (ii) $U_1$: an $SU(2)_L$-singlet vector leptoquark. In this paper, we show that, in fact, $VB$ and $U_1$ can be distinguished experimentally. $VB$ also contributes to $\\tau \\to 3\\mu$, while $U_1$ does not. $VB$ predicts $1.9 \\times 10^{-10} \\le {\\cal B}(\\tau^-\\to\\mu^-\\mu^+\\mu^-) \\le 2.1 \\times 10^{-8}$, which should be measurable at Belle II (and perhaps LHCb). $\\tau \\to 3\\mu$ is therefore a smoking-gun signal of $VB$. For $U_1$, there are several observables that may point to this model. Perhaps the most interesting is the lepton-flavor-violating decay $\\Upsilon(3S) \\to \\mu \\tau$, which h...

  16. Chromhome: A rich internet application for accessing comparative chromosome homology maps

    Directory of Open Access Journals (Sweden)

    Cox Tony

    2008-03-01

    map entire genomes and helps focus only on relevant regions of the chromosomes of the species under study. Future releases of Chromhome will accommodate more species and their respective gene and BAC maps, in addition to chromosome painting data. Chromhome application provides a single-page interface (SPI with desktop style layout, delivering a better and richer user experience.

  17. Marriage à-la-MOND: Baryonic dark matter in galaxy clusters and the cooling flow puzzle

    Science.gov (United States)

    Milgrom, Mordehai

    2008-05-01

    I start with a brief introduction to MOND phenomenology and its possible roots in cosmology—a notion that may turn out to be the most far reaching aspect of MOND. Next I discuss the implications of MOND for the dark matter (DM) doctrine: MOND's successes imply that baryons determine everything. For DM this would mean that the puny tail of leftover baryons in galaxies wags the hefty DM dog. This has to occur in many intricate ways, and despite the haphazard construction history of galaxies—a very tall order. I then concentrate on galaxy clusters in light of MOND, which still requires some yet undetected cluster dark matter, presumably in some baryonic form (CBDM). This CBDM might contribute to the heating of the X-ray emitting gas and thus alleviate the cooling flow puzzle. MOND, qua theory of dynamics, does not directly enter the microphysics of the gas; however, it does force a new outlook on the role of DM in shaping the cluster gas dynamics: MOND tells us that the cluster DM is not cold dark matter, is not so abundant, and is not expected in galaxies; it is thus not subject to constraints on baryonic DM in galaxies. The mass in CBDM required in a whole cluster is, typically, similar to that in hot gas, but is rather more centrally concentrated, totally dominating the core. The CBDM contribution to the baryon budget in the universe is thus small. Its properties, deduced for isolated clusters, are consistent with the observations of the "bullet cluster". Its kinetic energy reservoir is much larger than that of the hot gas in the core, and would suffice to keep the gas hot for many cooling times. Heating can be effected in various ways depending on the exact nature of the CBDM, from very massive black holes to cool, compact gas clouds.

  18. Solving the 56Ni Puzzle of Magnetar-powered Broad-lined Type IC Supernovae

    Science.gov (United States)

    Wang, Ling-Jun; Han, Yan-Hui; Xu, Dong; Wang, Shan-Qin; Dai, Zi-Gao; Wu, Xue-Feng; Wei, Jian-Yan

    2016-11-01

    Broad-lined Type Ic supernovae (SNe Ic-BL) are of great importance because their association with long-duration gamma-ray bursts (LGRBs) holds the key to deciphering the central engine of LGRBs, which refrains from being unveiled despite decades of investigation. Among the two popularly hypothesized types of central engine, i.e., black holes and strongly magnetized neutron stars (magnetars), there is mounting evidence that the central engine of GRB-associated SNe (GRB-SNe) is rapidly rotating magnetars. Theoretical analysis also suggests that magnetars could be the central engine of SNe Ic-BL. What puzzled the researchers is the fact that light-curve modeling indicates that as much as 0.2{--}0.5 {M}⊙ of 56Ni was synthesized during the explosion of the SNe Ic-BL, which is unfortunately in direct conflict with current state-of-the-art understanding of magnetar-powered 56Ni synthesis. Here we propose a dynamic model of magnetar-powered SNe to take into account the acceleration of the ejecta by the magnetar, as well as the thermalization of the injected energy. Assuming that the SN kinetic energy comes exclusively from the magnetar acceleration, we find that although a major fraction of the rotational energy of the magnetar is to accelerate the SN ejecta, a tiny fraction of this energy deposited as thermal energy of the ejecta is enough to reduce the needed 56Ni to 0.06 M ⊙ for both SN 1997ef and SN 2007ru. We therefore suggest that magnetars could power SNe Ic-BL in aspects both of energetics and of 56Ni synthesis.

  19. New data and an old puzzle: the negative association between schizophrenia and rheumatoid arthritis.

    Science.gov (United States)

    Lee, S Hong; Byrne, Enda M; Hultman, Christina M; Kähler, Anna; Vinkhuyzen, Anna A E; Ripke, Stephan; Andreassen, Ole A; Frisell, Thomas; Gusev, Alexander; Hu, Xinli; Karlsson, Robert; Mantzioris, Vasilis X; McGrath, John J; Mehta, Divya; Stahl, Eli A; Zhao, Qiongyi; Kendler, Kenneth S; Sullivan, Patrick F; Price, Alkes L; O'Donovan, Michael; Okada, Yukinori; Mowry, Bryan J; Raychaudhuri, Soumya; Wray, Naomi R; Byerley, William; Cahn, Wiepke; Cantor, Rita M; Cichon, Sven; Cormican, Paul; Curtis, David; Djurovic, Srdjan; Escott-Price, Valentina; Gejman, Pablo V; Georgieva, Lyudmila; Giegling, Ina; Hansen, Thomas F; Ingason, Andrés; Kim, Yunjung; Konte, Bettina; Lee, Phil H; McIntosh, Andrew; McQuillin, Andrew; Morris, Derek W; Nöthen, Markus M; O'Dushlaine, Colm; Olincy, Ann; Olsen, Line; Pato, Carlos N; Pato, Michele T; Pickard, Benjamin S; Posthuma, Danielle; Rasmussen, Henrik B; Rietschel, Marcella; Rujescu, Dan; Schulze, Thomas G; Silverman, Jeremy M; Thirumalai, Srinivasa; Werge, Thomas; Agartz, Ingrid; Amin, Farooq; Azevedo, Maria H; Bass, Nicholas; Black, Donald W; Blackwood, Douglas H R; Bruggeman, Richard; Buccola, Nancy G; Choudhury, Khalid; Cloninger, Robert C; Corvin, Aiden; Craddock, Nicholas; Daly, Mark J; Datta, Susmita; Donohoe, Gary J; Duan, Jubao; Dudbridge, Frank; Fanous, Ayman; Freedman, Robert; Freimer, Nelson B; Friedl, Marion; Gill, Michael; Gurling, Hugh; De Haan, Lieuwe; Hamshere, Marian L; Hartmann, Annette M; Holmans, Peter A; Kahn, René S; Keller, Matthew C; Kenny, Elaine; Kirov, George K; Krabbendam, Lydia; Krasucki, Robert; Lawrence, Jacob; Lencz, Todd; Levinson, Douglas F; Lieberman, Jeffrey A; Lin, Dan-Yu; Linszen, Don H; Magnusson, Patrik K E; Maier, Wolfgang; Malhotra, Anil K; Mattheisen, Manuel; Mattingsdal, Morten; McCarroll, Steven A; Medeiros, Helena; Melle, Ingrid; Milanova, Vihra; Myin-Germeys, Inez; Neale, Benjamin M; Ophoff, Roel A; Owen, Michael J; Pimm, Jonathan; Purcell, Shaun M; Puri, Vinay; Quested, Digby J; Rossin, Lizzy; Ruderfer, Douglas; Sanders, Alan R; Shi, Jianxin; Sklar, Pamela; St Clair, David; Stroup, T Scott; Van Os, Jim; Visscher, Peter M; Wiersma, Durk; Zammit, Stanley; Bridges, S Louis; Choi, Hyon K; Coenen, Marieke J H; de Vries, Niek; Dieud, Philippe; Greenberg, Jeffrey D; Huizinga, Tom W J; Padyukov, Leonid; Siminovitch, Katherine A; Tak, Paul P; Worthington, Jane; De Jager, Philip L; Denny, Joshua C; Gregersen, Peter K; Klareskog, Lars; Mariette, Xavier; Plenge, Robert M; van Laar, Mart; van Riel, Piet

    2015-10-01

    A long-standing epidemiological puzzle is the reduced rate of rheumatoid arthritis (RA) in those with schizophrenia (SZ) and vice versa. Traditional epidemiological approaches to determine if this negative association is underpinned by genetic factors would test for reduced rates of one disorder in relatives of the other, but sufficiently powered data sets are difficult to achieve. The genomics era presents an alternative paradigm for investigating the genetic relationship between two uncommon disorders. We use genome-wide common single nucleotide polymorphism (SNP) data from independently collected SZ and RA case-control cohorts to estimate the SNP correlation between the disorders. We test a genotype X environment (GxE) hypothesis for SZ with environment defined as winter- vs summer-born. We estimate a small but significant negative SNP-genetic correlation between SZ and RA (-0.046, s.e. 0.026, P = 0.036). The negative correlation was stronger for the SNP set attributed to coding or regulatory regions (-0.174, s.e. 0.071, P = 0.0075). Our analyses led us to hypothesize a gene-environment interaction for SZ in the form of immune challenge. We used month of birth as a proxy for environmental immune challenge and estimated the genetic correlation between winter-born and non-winter born SZ to be significantly less than 1 for coding/regulatory region SNPs (0.56, s.e. 0.14, P = 0.00090). Our results are consistent with epidemiological observations of a negative relationship between SZ and RA reflecting, at least in part, genetic factors. Results of the month of birth analysis are consistent with pleiotropic effects of genetic variants dependent on environmental context.

  20. Does the diffusion dark matter-dark energy interaction model solve cosmological puzzles?

    Science.gov (United States)

    Szydłowski, Marek; Stachowski, Aleksander

    2016-08-01

    We study dynamics of cosmological models with diffusion effects modeling dark matter and dark energy interactions. We show the simple model with diffusion between the cosmological constant sector and dark matter, where the canonical scaling law of dark matter (ρd m ,0a-3(t )) is modified by an additive ɛ (t )=γ t a-3(t ) to the form ρd m=ρd m ,0a-3(t )+ɛ (t ). We reduced this model to the autonomous dynamical system and investigate it using dynamical system methods. This system possesses a two-dimensional invariant submanifold on which the dark matter-dark energy (DM-DE) interaction can be analyzed on the phase plane. The state variables are density parameter for matter (dark and visible) and parameter δ characterizing the rate of growth of energy transfer between the dark sectors. A corresponding dynamical system belongs to a general class of jungle type of cosmologies represented by coupled cosmological models in a Lotka-Volterra framework. We demonstrate that the de Sitter solution is a global attractor for all trajectories in the phase space and there are two repellers: the Einstein-de Sitter universe and the de Sitter universe state dominating by the diffusion effects. We distinguish in the phase space trajectories, which become in good agreement with the data. They should intersect a rectangle with sides of Ωm ,0∈[0.2724 ,0.3624 ] , δ ∈[0.0000 ,0.0364 ] at the 95% CL. Our model could solve some of the puzzles of the Λ CDM model, such as the coincidence and fine-tuning problems. In the context of the coincidence problem, our model can explain the present ratio of ρm to ρd e, which is equal 0.457 6-0.0831+0.1109 at a 2 σ confidence level.

  1. Social class and health: the puzzling counter-example of British South Asians.

    Science.gov (United States)

    Williams, R; Wright, W; Hunt, K

    1998-11-01

    British South Asians (with ancestry from the Indian subcontinent) provided a puzzling exception to the British class gradient in mortality during the 1970s. On the assumption that class gradients in health are produced mainly by gradients in standard of living, this might be due to a break in the relation of class to standard of living (change in class structure), or by a break in the relation of standard of living to patterns of health behaviour and health risk (change in class lifestyles). Data on these characteristics are available from the West of Scotland Twenty-07 Study, where 159 South Asians aged 30-40 (mean age 35) were sampled alongside 319 of the general population in Glasgow. As regards changes in class structure, results indicate that the underclass thesis, which suggests that ethnic minorities are forced into less eligible jobs or into a separate labour market or into unemployment, resulting in a standard of living below that of the general population, still holds good for British South Asians in categories from social class III non-manual downwards. It does not hold good for owners of small businesses, where Sikhs and Hindus in particular have a standard of living equivalent to general population counterparts. However, prosperity is not predictable from levels of education in the subcontinent and from this and other signs it appears that a wholesale redistribution of class chances is occurring among British South Asians, disrupting inter-and intra-generational continuities in the relation between class and standard of living. There is little sign of change in class lifestyles, i.e. in the relation between standard of living and health behaviour or health risk. As yet, though, the new distribution of standard of living is affecting patterns of health behaviour and health risk more strongly than symptom experience or chronic illness, suggesting that a class gradient in health will re-emerge.

  2. The Formation of Galaxies and Supermassive Black Holes: Insights and Puzzles

    Science.gov (United States)

    Somerville, Rachel S.

    2014-01-01

    Galaxies exist at a nexus of physical scales, molded by physics ranging from the “small” scales of star formation and accretion onto nuclear black holes, up to the very large scales of the cosmic web. It is this special property that makes galaxies so fascinating and so challenging to study, both observationally and theoretically. The past two decades have seen enormous progress in our understanding of how galaxies form and evolve. We have surveyed slices of the sky at many wavelengths, and built sophisticated models and simulations that attempt to capture the complex array of physics that influences galaxy evolution. We are only now coming into possession of large samples of galaxies for which we can study the internal structure as well as the large scale environment in detail, from the epoch of ‘cosmic high noon’ ( 2) to the present. At the same time, numerical simulations set within a cosmological framework have only recently succeeded in building galaxies with realistic internal structures. It has been known for several years that galaxies are growing in mass and radius, experiencing morphological transformation, and ‘downsizing’ their star formation activity over cosmic time. Now, new observations are painting a picture in which the internal structure of galaxies (size and morphology) is intimately linked with their star formation activity and formation history. There are hints that the co-evolution of supermassive black holes with their host galaxies may be the driving force behind these correlations - but this remains controversial. While cosmological simulations set within the hierarchical formation scenario of Cold Dark Matter currently offer a plausible story for interpreting these observations, many puzzles remain. I will review recent insights gleaned from deep multi-wavelength surveys and state-of-the-art theoretical models and simulations, as well as highlight the open questions and challenges for the future.

  3. New data and an old puzzle: the negative association between schizophrenia and rheumatoid arthritis

    Science.gov (United States)

    Lee, S Hong; Byrne, Enda M; Hultman, Christina M; Kähler, Anna; Vinkhuyzen, Anna AE; Ripke, Stephan; Andreassen, Ole A; Frisell, Thomas; Gusev, Alexander; Hu, Xinli; Karlsson, Robert; Mantzioris, Vasilis X; McGrath, John J; Mehta, Divya; Stahl, Eli A; Zhao, Qiongyi; Kendler, Kenneth S; Sullivan, Patrick F; Price, Alkes L; O’Donovan, Michael; Okada, Yukinori; Mowry, Bryan J; Raychaudhuri, Soumya; Wray, Naomi R; Byerley, William; Cahn, Wiepke; Cantor, Rita M; Cichon, Sven; Cormican, Paul; Curtis, David; Djurovic, Srdjan; Escott-Price, Valentina; Gejman, Pablo V; Georgieva, Lyudmila; Giegling, Ina; Hansen, Thomas F; Ingason, Andrés; Kim, Yunjung; Konte, Bettina; Lee, Phil H; McIntosh, Andrew; McQuillin, Andrew; Morris, Derek W; Nöthen, Markus M; O’Dushlaine, Colm; Olincy, Ann; Olsen, Line; Pato, Carlos N; Pato, Michele T; Pickard, Benjamin S; Posthuma, Danielle; Rasmussen, Henrik B; Rietschel, Marcella; Rujescu, Dan; Schulze, Thomas G; Silverman, Jeremy M; Thirumalai, Srinivasa; Werge, Thomas; Agartz, Ingrid; Amin, Farooq; Azevedo, Maria H; Bass, Nicholas; Black, Donald W; Blackwood, Douglas H R; Bruggeman, Richard; Buccola, Nancy G; Choudhury, Khalid; Cloninger, Robert C; Corvin, Aiden; Craddock, Nicholas; Daly, Mark J; Datta, Susmita; Donohoe, Gary J; Duan, Jubao; Dudbridge, Frank; Fanous, Ayman; Freedman, Robert; Freimer, Nelson B; Friedl, Marion; Gill, Michael; Gurling, Hugh; De Haan, Lieuwe; Hamshere, Marian L; Hartmann, Annette M; Holmans, Peter A; Kahn, René S; Keller, Matthew C; Kenny, Elaine; Kirov, George K; Krabbendam, Lydia; Krasucki, Robert; Lawrence, Jacob; Lencz, Todd; Levinson, Douglas F; Lieberman, Jeffrey A; Lin, Dan-Yu; Linszen, Don H; Magnusson, Patrik KE; Maier, Wolfgang; Malhotra, Anil K; Mattheisen, Manuel; Mattingsdal, Morten; McCarroll, Steven A; Medeiros, Helena; Melle, Ingrid; Milanova, Vihra; Myin-Germeys, Inez; Neale, Benjamin M; Ophoff, Roel A; Owen, Michael J; Pimm, Jonathan; Purcell, Shaun M; Puri, Vinay; Quested, Digby J; Rossin, Lizzy; Ruderfer, Douglas; Sanders, Alan R; Shi, Jianxin; Sklar, Pamela; St. Clair, David; Stroup, T Scott; Van Os, Jim; Visscher, Peter M; Wiersma, Durk; Zammit, Stanley; Bridges, S Louis; Choi, Hyon K; Coenen, Marieke JH; de Vries, Niek; Dieud, Philippe; Greenberg, Jeffrey D; Huizinga, Tom WJ; Padyukov, Leonid; Siminovitch, Katherine A; Tak, Paul P; Worthington, Jane; De Jager, Philip L; Denny, Joshua C; Gregersen, Peter K; Klareskog, Lars; Mariette, Xavier; Plenge, Robert M; van Laar, Mart; van Riel, Piet

    2015-01-01

    Background: A long-standing epidemiological puzzle is the reduced rate of rheumatoid arthritis (RA) in those with schizophrenia (SZ) and vice versa. Traditional epidemiological approaches to determine if this negative association is underpinned by genetic factors would test for reduced rates of one disorder in relatives of the other, but sufficiently powered data sets are difficult to achieve. The genomics era presents an alternative paradigm for investigating the genetic relationship between two uncommon disorders. Methods: We use genome-wide common single nucleotide polymorphism (SNP) data from independently collected SZ and RA case-control cohorts to estimate the SNP correlation between the disorders. We test a genotype X environment (GxE) hypothesis for SZ with environment defined as winter- vs summer-born. Results: We estimate a small but significant negative SNP-genetic correlation between SZ and RA (−0.046, s.e. 0.026, P = 0.036). The negative correlation was stronger for the SNP set attributed to coding or regulatory regions (−0.174, s.e. 0.071, P = 0.0075). Our analyses led us to hypothesize a gene-environment interaction for SZ in the form of immune challenge. We used month of birth as a proxy for environmental immune challenge and estimated the genetic correlation between winter-born and non-winter born SZ to be significantly less than 1 for coding/regulatory region SNPs (0.56, s.e. 0.14, P  = 0.00090). Conclusions: Our results are consistent with epidemiological observations of a negative relationship between SZ and RA reflecting, at least in part, genetic factors. Results of the month of birth analysis are consistent with pleiotropic effects of genetic variants dependent on environmental context. PMID:26286434

  4. Identifying sediment discontinuities and solving dating puzzles using monitoring and palaeolimnological records

    Science.gov (United States)

    Dong, Xuhui; Sayer, Carl D.; Bennion, Helen; Maberly, Stephen C.; Yang, Handong; Battarbee, Richard W.

    2016-12-01

    Palaeolimnological studies should ideally be based upon continuous, undisturbed sediment sequences with reliable chronologies. However for some lake cores, these conditions are not met and palaeolimnologists are often faced with dating puzzles caused by sediment disturbances in the past. This study chooses Esthwaite Water from England to illustrate how to identify sedimentation discontinuities in lake cores and how chronologies can be established for imperfect cores by correlation of key sediment signatures in parallel core records and with long-term monitoring data (1945-2003). Replicated short cores (ESTH1, ESTH7, and ESTH8) were collected and subjected to loss-on-ignition, radiometric dating (210Pb, 137Cs, and 14C), particle size, trace metal, and fossil diatom analysis. Both a slumping and a hiatus event were detected in ESTH7 based on comparisons made between the cores and the long-term diatom data. Ordination analysis suggested that the slumped material in ESTH7 originated from sediment deposited around 1805-1880 AD. Further, it was inferred that the hiatus resulted in a loss of sediment deposited from 1870 to 1970 AD. Given the existence of three superior 14C dates in ESTH7, ESTH1 and ESTH7 were temporally correlated by multiple palaeolimnological proxies for age-depth model development. High variability in sedimentation rates was evident, but good agreement across the various palaeolimnological proxies indicated coherence in sediment processes within the coring area. Differences in sedimentation rates most likely resulted from the natural morphology of the lake basin. Our study suggests that caution is required in selecting suitable coring sites for palaeolimnological studies of small, relatively deep lakes and that proximity to steep slopes should be avoided wherever possible. Nevertheless, in some cases, comparisons between a range of contemporary and palaeolimnological records can be employed to diagnose sediment disturbances and establish a chronology.

  5. RNA-Puzzles Round II: assessment of RNA structure prediction programs applied to three large RNA structures.

    Science.gov (United States)

    Miao, Zhichao; Adamiak, Ryszard W; Blanchet, Marc-Frédérick; Boniecki, Michal; Bujnicki, Janusz M; Chen, Shi-Jie; Cheng, Clarence; Chojnowski, Grzegorz; Chou, Fang-Chieh; Cordero, Pablo; Cruz, José Almeida; Ferré-D'Amaré, Adrian R; Das, Rhiju; Ding, Feng; Dokholyan, Nikolay V; Dunin-Horkawicz, Stanislaw; Kladwang, Wipapat; Krokhotin, Andrey; Lach, Grzegorz; Magnus, Marcin; Major, François; Mann, Thomas H; Masquida, Benoît; Matelska, Dorota; Meyer, Mélanie; Peselis, Alla; Popenda, Mariusz; Purzycka, Katarzyna J; Serganov, Alexander; Stasiewicz, Juliusz; Szachniuk, Marta; Tandon, Arpit; Tian, Siqi; Wang, Jian; Xiao, Yi; Xu, Xiaojun; Zhang, Jinwei; Zhao, Peinan; Zok, Tomasz; Westhof, Eric

    2015-06-01

    This paper is a report of a second round of RNA-Puzzles, a collective and blind experiment in three-dimensional (3D) RNA structure prediction. Three puzzles, Puzzles 5, 6, and 10, represented sequences of three large RNA structures with limited or no homology with previously solved RNA molecules. A lariat-capping ribozyme, as well as riboswitches complexed to adenosylcobalamin and tRNA, were predicted by seven groups using RNAComposer, ModeRNA/SimRNA, Vfold, Rosetta, DMD, MC-Fold, 3dRNA, and AMBER refinement. Some groups derived models using data from state-of-the-art chemical-mapping methods (SHAPE, DMS, CMCT, and mutate-and-map). The comparisons between the predictions and the three subsequently released crystallographic structures, solved at diffraction resolutions of 2.5-3.2 Å, were carried out automatically using various sets of quality indicators. The comparisons clearly demonstrate the state of present-day de novo prediction abilities as well as the limitations of these state-of-the-art methods. All of the best prediction models have similar topologies to the native structures, which suggests that computational methods for RNA structure prediction can already provide useful structural information for biological problems. However, the prediction accuracy for non-Watson-Crick interactions, key to proper folding of RNAs, is low and some predicted models had high Clash Scores. These two difficulties point to some of the continuing bottlenecks in RNA structure prediction. All submitted models are available for download at http://ahsoka.u-strasbg.fr/rnapuzzles/.

  6. RNA-Puzzles Round II: assessment of RNA structure prediction programs applied to three large RNA structures

    Science.gov (United States)

    Miao, Zhichao; Adamiak, Ryszard W.; Blanchet, Marc-Frédérick; Boniecki, Michal; Bujnicki, Janusz M.; Chen, Shi-Jie; Cheng, Clarence; Chojnowski, Grzegorz; Chou, Fang-Chieh; Cordero, Pablo; Cruz, José Almeida; Ferré-D'Amaré, Adrian R.; Das, Rhiju; Ding, Feng; Dokholyan, Nikolay V.; Dunin-Horkawicz, Stanislaw; Kladwang, Wipapat; Krokhotin, Andrey; Lach, Grzegorz; Magnus, Marcin; Major, François; Mann, Thomas H.; Masquida, Benoît; Matelska, Dorota; Meyer, Mélanie; Peselis, Alla; Popenda, Mariusz; Purzycka, Katarzyna J.; Serganov, Alexander; Stasiewicz, Juliusz; Szachniuk, Marta; Tandon, Arpit; Tian, Siqi; Wang, Jian; Xiao, Yi; Xu, Xiaojun; Zhang, Jinwei; Zhao, Peinan; Zok, Tomasz; Westhof, Eric

    2015-01-01

    This paper is a report of a second round of RNA-Puzzles, a collective and blind experiment in three-dimensional (3D) RNA structure prediction. Three puzzles, Puzzles 5, 6, and 10, represented sequences of three large RNA structures with limited or no homology with previously solved RNA molecules. A lariat-capping ribozyme, as well as riboswitches complexed to adenosylcobalamin and tRNA, were predicted by seven groups using RNAComposer, ModeRNA/SimRNA, Vfold, Rosetta, DMD, MC-Fold, 3dRNA, and AMBER refinement. Some groups derived models using data from state-of-the-art chemical-mapping methods (SHAPE, DMS, CMCT, and mutate-and-map). The comparisons between the predictions and the three subsequently released crystallographic structures, solved at diffraction resolutions of 2.5–3.2 Å, were carried out automatically using various sets of quality indicators. The comparisons clearly demonstrate the state of present-day de novo prediction abilities as well as the limitations of these state-of-the-art methods. All of the best prediction models have similar topologies to the native structures, which suggests that computational methods for RNA structure prediction can already provide useful structural information for biological problems. However, the prediction accuracy for non-Watson–Crick interactions, key to proper folding of RNAs, is low and some predicted models had high Clash Scores. These two difficulties point to some of the continuing bottlenecks in RNA structure prediction. All submitted models are available for download at http://ahsoka.u-strasbg.fr/rnapuzzles/. PMID:25883046

  7. Definition of a visuospatial dimension as a step forward in the diagnostic puzzle of nonverbal learning disability.

    Science.gov (United States)

    Poletti, Michele

    2016-03-17

    Although clinically recognized for almost 50 years, the categorical distinction of specific learning disabilities due to an impairment of the nonverbal domain (nonverbal learning disability [NLD]) is still debated and controversial. Unsolved issues involve theoretical models, diagnostic criteria, rehabilitative interventions, and moderator factors. These issues are briefly overviewed to sustain the need for a shift toward dimensional approaches, as suggested by research domain criteria, as a step forward in the diagnostic puzzle of NLD. With this aim, a visuospatial dimension, or spectrum, is proposed, and then clinical conditions that may fit with its impaired side are systemized, while specifying in which conditions a visuospatial impairment may be considered an NLD.

  8. The Sirius System and Its Astrophysical Puzzles: Hubble Space Telescope and Ground-based Astrometry

    Science.gov (United States)

    Bond, Howard E.; Schaefer, Gail H.; Gilliland, Ronald L.; Holberg, Jay B.; Mason, Brian D.; Lindenblad, Irving W.; Seitz-McLeese, Miranda; Arnett, W. David; Demarque, Pierre; Spada, Federico; Young, Patrick A.; Barstow, Martin A.; Burleigh, Matthew R.; Gudehus, Donald

    2017-05-01

    Sirius, the seventh-nearest stellar system, is a visual binary containing the metallic-line A1 V star Sirius A, the brightest star in the sky, orbited in a 50.13 year period by Sirius B, the brightest and nearest white dwarf (WD). Using images obtained over nearly two decades with the Hubble Space Telescope (HST), along with photographic observations covering almost 20 years and nearly 2300 historical measurements dating back to the 19th century, we determine precise orbital elements for the visual binary. Combined with the parallax and the motion of the A component, these elements yield dynamical masses of 2.063+/- 0.023 {M}⊙ and 1.018+/- 0.011 {M}⊙ for Sirius A and B, respectively. Our precise HST astrometry rules out third bodies orbiting either star in the system, down to masses of ˜15-25 {M}{Jup}. The location of Sirius B in the Hertzsprung-Russell diagram is in excellent agreement with theoretical cooling tracks for WDs of its dynamical mass, and implies a cooling age of ˜126 Myr. The position of Sirius B on the mass-radius plane is also consistent with WD theory, assuming a carbon-oxygen core. Including the pre-WD evolutionary timescale of the assumed progenitor, the total age of Sirius B is about 228 ± 10 Myr. We calculated evolutionary tracks for stars with the dynamical mass of Sirius A, using two independent codes. We find it necessary to assume a slightly subsolar metallicity, of about 0.85 {Z}⊙ , to fit its location on the luminosity-radius plane. The age of Sirius A based on these models is about 237-247 Myr, with uncertainties of ±15 Myr, consistent with that of the WD companion. We discuss astrophysical puzzles presented by the Sirius system, including the probability that the two stars must have interacted in the past, even though there is no direct evidence for this and the orbital eccentricity remains high. Based in part on observations with the NASA/ESA Hubble Space Telescope obtained at the Space Telescope Science Institute, and from

  9. Juggling the life-puzzle with Geosciences: personal experience and strategies from a female leader

    Science.gov (United States)

    Arheimer, Berit

    2017-04-01

    recommendations from being a single-mother with scientific and international ambitions, working in an operational environment, on how to juggle the dynamic life puzzle.

  10. On the reversibility of the Meissner effect and the angular momentum puzzle

    Energy Technology Data Exchange (ETDEWEB)

    Hirsch, J.E., E-mail: jhirsch@ucsd.edu

    2016-10-15

    suppress Foucault currents, charge has to flow in direction perpendicular to the phase boundary. • The charge carriers have to be holes. • This solves also the angular momentum puzzle associated with the Meissner effect.

  11. There and back again: Two views on the protein folding puzzle

    Science.gov (United States)

    Finkelstein, Alexei V.; Badretdin, Azat J.; Galzitskaya, Oxana V.; Ivankov, Dmitry N.; Bogatyreva, Natalya S.; Garbuzynskiy, Sergiy O.

    2017-07-01

    The ability of protein chains to spontaneously form their spatial structures is a long-standing puzzle in molecular biology. Experimentally measured folding times of single-domain globular proteins range from microseconds to hours: the difference (10-11 orders of magnitude) is the same as that between the life span of a mosquito and the age of the universe. This review describes physical theories of rates of overcoming the free-energy barrier separating the natively folded (N) and unfolded (U) states of protein chains in both directions: ;U-to-N; and ;N-to-U;. In the theory of protein folding rates a special role is played by the point of thermodynamic (and kinetic) equilibrium between the native and unfolded state of the chain; here, the theory obtains the simplest form. Paradoxically, a theoretical estimate of the folding time is easier to get from consideration of protein unfolding (the ;N-to-U; transition) rather than folding, because it is easier to outline a good unfolding pathway of any structure than a good folding pathway that leads to the stable fold, which is yet unknown to the folding protein chain. And since the rates of direct and reverse reactions are equal at the equilibrium point (as follows from the physical ;detailed balance; principle), the estimated folding time can be derived from the estimated unfolding time. Theoretical analysis of the ;N-to-U; transition outlines the range of protein folding rates in a good agreement with experiment. Theoretical analysis of folding (the ;U-to-N; transition), performed at the level of formation and assembly of protein secondary structures, outlines the upper limit of protein folding times (i.e., of the time of search for the most stable fold). Both theories come to essentially the same results; this is not a surprise, because they describe overcoming one and the same free-energy barrier, although the way to the top of this barrier from the side of the unfolded state is very different from the way from the

  12. Disentangling Puzzles of Spatial Scales and Participation in Environmental Governance-The Case of Governance Re-scaling Through the European Water Framework Directive.

    Science.gov (United States)

    Newig, Jens; Schulz, Daniel; Jager, Nicolas W

    2016-12-01

    This article attempts to shed new light on prevailing puzzles of spatial scales in multi-level, participatory governance as regards the democratic legitimacy and environmental effectiveness of governance systems. We focus on the governance re-scaling by the European Water Framework Directive, which introduced new governance scales (mandated river basin management) and demands consultation of citizens and encourages 'active involvement' of stakeholders. This allows to examine whether and how re-scaling through deliberate governance interventions impacts on democratic legitimacy and effective environmental policy delivery. To guide the enquiry, this article organizes existing-partly contradictory-claims on the relation of scale, democratic legitimacy, and environmental effectiveness into three clusters of mechanisms, integrating insights from multi-level governance, social-ecological systems, and public participation. We empirically examine Water Framework Directive implementation in a comparative case study of multi-level systems in the light of the suggested mechanisms. We compare two planning areas in Germany: North Rhine Westphalia and Lower Saxony. Findings suggest that the Water Framework Directive did have some impact on institutionalizing hydrological scales and participation. Local participation appears generally both more effective and legitimate than on higher levels, pointing to the need for yet more tailored multi-level governance approaches, depending on whether environmental knowledge or advocacy is sought. We find mixed results regarding the potential of participation to bridge spatial 'misfits' between ecological and administrative scales of governance, depending on the historical institutionalization of governance on ecological scales. Polycentricity, finally, appeared somewhat favorable in effectiveness terms with some distinct differences regarding polycentricity in planning vs. polycentricity in implementation.

  13. Disentangling Puzzles of Spatial Scales and Participation in Environmental Governance—The Case of Governance Re-scaling Through the European Water Framework Directive

    Science.gov (United States)

    Newig, Jens; Schulz, Daniel; Jager, Nicolas W.

    2016-12-01

    This article attempts to shed new light on prevailing puzzles of spatial scales in multi-level, participatory governance as regards the democratic legitimacy and environmental effectiveness of governance systems. We focus on the governance re-scaling by the European Water Framework Directive, which introduced new governance scales (mandated river basin management) and demands consultation of citizens and encourages `active involvement' of stakeholders. This allows to examine whether and how re-scaling through deliberate governance interventions impacts on democratic legitimacy and effective environmental policy delivery. To guide the enquiry, this article organizes existing—partly contradictory—claims on the relation of scale, democratic legitimacy, and environmental effectiveness into three clusters of mechanisms, integrating insights from multi-level governance, social-ecological systems, and public participation. We empirically examine Water Framework Directive implementation in a comparative case study of multi-level systems in the light of the suggested mechanisms. We compare two planning areas in Germany: North Rhine Westphalia and Lower Saxony. Findings suggest that the Water Framework Directive did have some impact on institutionalizing hydrological scales and participation. Local participation appears generally both more effective and legitimate than on higher levels, pointing to the need for yet more tailored multi-level governance approaches, depending on whether environmental knowledge or advocacy is sought. We find mixed results regarding the potential of participation to bridge spatial `misfits' between ecological and administrative scales of governance, depending on the historical institutionalization of governance on ecological scales. Polycentricity, finally, appeared somewhat favorable in effectiveness terms with some distinct differences regarding polycentricity in planning vs. polycentricity in implementation.

  14. The Three-Color and Two-Color Tantrix(TM) Rotation Puzzle Problems are NP-Complete via Parsimonious Reductions

    CERN Document Server

    Baumeister, Dorothea

    2007-01-01

    Holzer and Holzer (Discrete Applied Mathematics 144(3):345--358, 2004) proved the Tantrix(TM) rotation puzzle problem with four colors NP-complete. Baumeister and Rothe (MCU 2007) modified their construction to achieve a parsimonious reduction from satisfiability to this problem. Since parsimonious reductions preserve the number of solutions, it follows that the unique version of the four-color Tantrix(TM) rotation puzzle problem is DP-complete under randomized reductions. In this paper, we study the three-color and the two-color Tantrix(TM) rotation puzzle problem. Restricting the number of allowed colors to three (respectively, to two) reduces the set of available Tantrix(TM) tiles from 56 to 14 (respectively, to 8). We prove that both the three-color and the two-color Tantrix(TM) rotation puzzle problem is NP-complete, which answers a question raised by Holzer and Holzer in the affirmative. Since both these reductions are parsimonious, it follows that both the unique three-color and the unique two-color Ta...

  15. Unraveling a 146 years old taxonomic puzzle: validation of Malabar snakehead, species-status and its relevance for channid systematics and evolution.

    Directory of Open Access Journals (Sweden)

    Allen Benziger

    Full Text Available BACKGROUND: The Malabar snakehead Channa diplogramma is one of the most enigmatic and least understood species within the family Channidae, which comprise one of the most important groups of freshwater food fish in tropical Asia. Since its description from peninsular India in 1865, it has remained a taxonomic puzzle with many researchers questioning its validity, based on its striking similarity with the South East Asian C. micropeltes. In this study, we assessed the identity of the Malabar snakehead, C. diplogramma, using morphological and molecular genetic analyses, and also evaluated its phylogenetic relationships and evolutionary biogeography. METHODOLOGY/PRINCIPAL FINDINGS: The morphometric and meristic analysis provided conclusive evidence to separate C. diplogramma and C. micropeltes as two distinct species. Number of caudal fin rays, lateral line scales, scales below lateral line; total vertebrae, pre-anal length and body depth were the most prominent characters that can be used to differentiate both the species. Channa diplogramma also shows several ontogenic color phases during its life history, which is shared with C. micropeltes. Finally, the genetic distance between both species for the partial mitochondrial 16S rRNA and COI sequences is also well above the intra-specific genetic distances of any other channid species compared in this study. CONCLUSIONS/SIGNIFICANCE: The current distribution of C. diplogramma and C. micropeltes is best explained by vicariance. The significant variation in the key taxonomic characters and the results of the molecular marker analysis points towards an allopatric speciation event or vicariant divergence from a common ancestor, which molecular data suggests to have occurred as early as 21.76 million years ago. The resurrection of C. diplogramma from the synonymy of C. micropeltes has hence been confirmed 146 years after its initial description and 134 years after it was synonymised, establishing it is

  16. Triángulos cuadrados y cruces cuadradas: algunos puzzles geométricos de H. E. Dudeney

    Directory of Open Access Journals (Sweden)

    Francisco Pérez Arribas

    2012-04-01

    Full Text Available Henry Ernest Dudeney (1857-1930 fue un autor inglés, conocido por los retos y acertijos matemáticos que publicó a lo largo de su vida en distintas revistas y que han sido recopilados posteriormente en distintos libros. Algunos de sus más de 200 retos tienen interesantes propiedades geométricas que pueden ser exploradas y mostradas con claridad, usando herramientas informáticas actuales. Este artículo presenta y analiza dos puzzles (disecciones de gran atractivo geométrico: la transformación de un triángulo equilátero en un cuadrado, y la transformación de una curiosa cruz en un cuadrado.

  17. 相对财富与股票溢价之谜%Relative Wealth and the Equity Premium Puzzle

    Institute of Scientific and Technical Information of China (English)

    毕先萍; 肖争艳; 李正友

    2004-01-01

    Mehra和Prescott(1985)提出著名的股票溢价之谜(Equity Premium Puzzle):合理的相对风险规避系数,不能解释美国S&P500指数的收益率为什么比无风险债券的收益率高出6个百分点.本文提出了一个基于相对财富的资产定价模型,其中代表性投资者的效用函数不但依赖于消费,还依赖于投资者的绝对财富,及社会平均财富.本文使用该模型,解释了股票溢价之谜.

  18. Double-pionic fusion of nuclear systems and the "ABC" effect: approaching a puzzle by exclusive and kinematically complete measurements.

    Science.gov (United States)

    Bashkanov, M; Bargholtz, C; Berłowski, M; Bogoslawsky, D; Calén, H; Clement, H; Demiroers, L; Doroshkevich, E; Duniec, D; Ekström, C; Fransson, K; Geren, L; Gustafsson, L; Höistad, B; Ivanov, G; Jacewicz, M; Jiganov, E; Johansson, T; Khakimova, O; Keleta, S; Koch, I; Kren, F; Kullander, S; Kupść, A; Lindberg, K; Marciniewski, P; Meier, R; Morosov, B; Pauly, C; Pettersson, H; Petukhov, Y; Povtorejko, A; Pricking, A; Ruber, R J M Y; Schönning, K; Scobel, W; Shwartz, B; Skorodko, T; Sopov, V; Stepaniak, J; Tegner, P-E; Thörngren-Engblom, P; Tikhomirov, V; Turowiecki, A; Wagner, G J; Wolke, M; Zabierowski, J; Zartova, I; Złomanczuk, J

    2009-02-06

    The ABC effect-a puzzling low-mass enhancement in the pipi invariant mass spectrum, first observed by Abashian, Booth, and Crowe-is well known from inclusive measurements of two-pion production in nuclear fusion reactions. Here we report on the first exclusive and kinematically complete measurements of the most basic double-pionic fusion reaction pn-->dpi;{0}pi;{0} at beam energies of 1.03 and 1.35 GeV. The measurements, which have been carried out at CELSIUS-WASA, reveal the ABC effect to be a (pipi)_{I=L=0} channel phenomenon associated with both a resonancelike energy dependence in the integral cross section and the formation of a DeltaDelta system in the intermediate state. A corresponding simple s-channel resonance ansatz provides a surprisingly good description of the data.

  19. Double-Pionic Fusion of Nuclear Systems and the ``ABC'' Effect: Approaching a Puzzle by Exclusive and Kinematically Complete Measurements

    Science.gov (United States)

    Bashkanov, M.; Bargholtz, C.; Berłowski, M.; Bogoslawsky, D.; Calén, H.; Clement, H.; Demiroers, L.; Doroshkevich, E.; Duniec, D.; Ekström, C.; Fransson, K.; Geren, L.; Gustafsson, L.; Höistad, B.; Ivanov, G.; Jacewicz, M.; Jiganov, E.; Johansson, T.; Khakimova, O.; Keleta, S.; Koch, I.; Kren, F.; Kullander, S.; Kupść, A.; Lindberg, K.; Marciniewski, P.; Meier, R.; Morosov, B.; Pauly, C.; Pettersson, H.; Petukhov, Y.; Povtorejko, A.; Pricking, A.; Ruber, R. J. M. Y.; Schönning, K.; Scobel, W.; Shwartz, B.; Skorodko, T.; Sopov, V.; Stepaniak, J.; Tegner, P.-E.; Thörngren-Engblom, P.; Tikhomirov, V.; Turowiecki, A.; Wagner, G. J.; Wolke, M.; Zabierowski, J.; Zartova, I.; Złomanczuk, J.

    2009-02-01

    The ABC effect—a puzzling low-mass enhancement in the ππ invariant mass spectrum, first observed by Abashian, Booth, and Crowe—is well known from inclusive measurements of two-pion production in nuclear fusion reactions. Here we report on the first exclusive and kinematically complete measurements of the most basic double-pionic fusion reaction pn→dπ0π0 at beam energies of 1.03 and 1.35 GeV. The measurements, which have been carried out at CELSIUS-WASA, reveal the ABC effect to be a (ππ)I=L=0 channel phenomenon associated with both a resonancelike energy dependence in the integral cross section and the formation of a ΔΔ system in the intermediate state. A corresponding simple s-channel resonance ansatz provides a surprisingly good description of the data.

  20. Double-Pionic Fusion of Nuclear Systems and the ABCEffect -- Aproaching a Puzzle by Exclusive and Kinematically Complete Measurements

    CERN Document Server

    Bashkanov, M; Berlowski, M; Bogoslawsky, D; Calén, H; Clement, H; Demiroers, L; Doroshkevich, E; Duniec, D; Ekström, C; Fransson, K; Geren, L; Gustafsson, L; Höistad, B; Ivanov, G; Jacewicz, M; Jiganov, E; Johansson, T; Khakimova, O; Keleta, S; Koch, I; Kren, F; Kullander, Sven; Kupsc, A; Lindberg, K; Marciniewski, P; Meier, R; Morosov, B; Pauly, C; Pettersson, H; Petukhov, Yu P; Povtorejko, A; Pricking, A; Ruber, R J M Y; Schonning, K; Scobel, W; Shwartz, B; Skorodko, T; Sopov, V; Stepaniak, J; Tegner, P -E; Thorngren-Engblom, P; Tikhomirov, V; Turowiecki, A; Wagner, G J; Wolke, M; Zabierowski, J; Zartova, I; Zlomanczuk, Yu

    2008-01-01

    The ABC effect - a puzzling low-mass enhancement in the $\\pi\\pi$ invariant mass spectrum - is well-known from inclusive measurements of two-pion production in nuclear fusion reactions. Here we report on first exclusive and kinematically complete measurements of solid statistics, which have been carried out at CELSIUS-WASA for the fusion reactions leading to d and $^3$He in the final states. These measurements reveal the ABC effect to be a $\\sigma$ channel phenomenon associated with the formation of an isoscalar dibaryonic resonance in connection with a $\\Delta\\Delta$ system in the intermediate state. A corresponding theoretical ansatz provides an adequate description both for the differential distributions and for the resonance-like energy dependence of the integral cross section.

  1. RED DWARF DYNAMO RAISES PUZZLE OVER INTERIORS OF LOWEST-MASS STARS

    Science.gov (United States)

    2002-01-01

    -years away in the constellation Aquila. Gliese 752A is a red dwarf that is one-third the mass of the Sun and slightly more than half its diameter. By contrast, VB10 is physically smaller than the planet Jupiter and only about nine percent the mass of our Sun. This very faint star is near the threshold of the lowest possible mass for a true star (.08 solar masses), below which nuclear fusion processes cannot take place according to current models. A team led by Linsky used Hubble's Goddard High Resolution Spectrograph (GHRS) to make a one-hour long exposure of VB10 on October 12, 1994. No detectable ultraviolet emission was seen until the last five minutes, when bright emission was detected in a flare. Though the star's normal surface temperature is 4,500 degrees Fahrenheit, Hubble's GHRS detected a sudden burst of 270,000 degrees Fahrenheit in the star's outer atmosphere. Linsky attributes this rapid heating to the presence of an intense, but unstable, magnetic field. THE INTERIOR WORKINGS OF A STELLAR DYNAMO Before the Hubble observation, astronomers thought magnetic fields in stars required the same dynamo process which creates magnetic fields on the Sun. In the classic solar model, heat generated by nuclear fusion reactions at the star's center escapes through a radiative zone just outside the core. The heat travels from the radiative core to the star's surface through a convection zone. In this region, heat bubbles to the surface by motions similar to boiling in a pot of water. Dynamos, which accelerate electrons to create magnetic forces, operate when the interior of a star rotates faster than the surface. Recent studies of the Sun indicate its convective zone rotates at nearly the same rate at all depths. This means the solar dynamo must operate in the more rapidly rotating radiative core just below the convective zone. The puzzle is that stars below 20 percent the mass of our Sun do not have radiative cores, but instead transport heat from their core through

  2. Puzzling with online games (BAM-COG): reliability, validity, and feasibility of an online self-monitor for cognitive performance in aging adults.

    Science.gov (United States)

    Aalbers, Teun; Baars, Maria A E; Olde Rikkert, Marcel G M; Kessels, Roy P C

    2013-12-03

    Online interventions are aiming increasingly at cognitive outcome measures but so far no easy and fast self-monitors for cognition have been validated or proven reliable and feasible. This study examines a new instrument called the Brain Aging Monitor-Cognitive Assessment Battery (BAM-COG) for its alternate forms reliability, face and content validity, and convergent and divergent validity. Also, reference values are provided. The BAM-COG consists of four easily accessible, short, yet challenging puzzle games that have been developed to measure working memory ("Conveyer Belt"), visuospatial short-term memory ("Sunshine"), episodic recognition memory ("Viewpoint"), and planning ("Papyrinth"). A total of 641 participants were recruited for this study. Of these, 397 adults, 40 years and older (mean 54.9, SD 9.6), were eligible for analysis. Study participants played all games three times with 14 days in between sets. Face and content validity were based on expert opinion. Alternate forms reliability (AFR) was measured by comparing scores on different versions of the BAM-COG and expressed with an intraclass correlation (ICC: two-way mixed; consistency at 95%). Convergent validity (CV) was provided by comparing BAM-COG scores to gold-standard paper-and-pencil and computer-assisted cognitive assessment. Divergent validity (DV) was measured by comparing BAM-COG scores to the National Adult Reading Test IQ (NART-IQ) estimate. Both CV and DV are expressed as Spearman rho correlation coefficients. Three out of four games showed adequate results on AFR, CV, and DV measures. The games Conveyer Belt, Sunshine, and Papyrinth have AFR ICCs of .420, .426, and .645 respectively. Also, these games had good to very good CV correlations: rho=.577 (P=.001), rho=.669 (Pgame Viewpoint provided less desirable results with an AFR ICC of .167, CV rho=.202 (P=.15), and DV rho=-.162 (P=.21). This study provides evidence for the use of the BAM-COG test battery as a feasible, reliable, and

  3. ESA's Rosetta mission and the puzzles that Hale-Bopp left behind

    Science.gov (United States)

    1997-04-01

    kilometres with a set of remote-sensing instruments. As the spacecraft moves around the nucleus at a very leisurely walking pace, other onboard instruments will analyse the dust and vapours, which will emanate from Comet Wirtanen with ever-increasing vigour as the Sun's rays warm it. Rosetta will drop a lander on to the comet's surface, for close inspection of its physical condition and chemical composition. The lander is a venture led by Germany, France and Italy, with participation from Austria, Finland, Hungary, Poland and the UK. As a box packed with scientific instruments and standing on three legs, the lander will be capable of anchoring itself to one spot and drilling into the surface. It may also be able to hop like a flea to visit another part of the nucleus. A combination of solar energy and electric batteries will enable operations to last for several months. "The combination of Rosetta in orbit around the comet and the lander on its surface is very powerful from a scientific point of view," says Gerhard Schwehm, ESA's project scientist for Rosetta. "We shall watch Comet Wirtanen brewing up like a volcano as it feels the heat of the Sun. In place of hazy impressions of the nucleus of a comet half hidden by its dust clouds, we shall see all the details with unprecedented clarity." Unanswered questions During and after the 1986 appearance of Halley's Comet, comet science made great progress. More recent comets have revealed important secrets to ESA's Infrared Space Observatory and to other space telescopes examining them at wavelengths unobservable from the Earth. Yet basic questions about comets remain unanswered. Just as the Rosetta Stone was the key that unlocked the meaning of Egyptian hieroglyphs, so the Rosetta spacecraft is intended to decipher the meaning of comets and their role in the origin and history of the Solar System. Here are a few of the main puzzles. * What does a comet weigh? Guesses about the density of cometary material vary widely, and only an

  4. Puzzling out the proton radius puzzle

    Directory of Open Access Journals (Sweden)

    Mihovilovič Miha

    2014-01-01

    Full Text Available The discrepancy between the proton charge radius extracted from the muonic hydrogen Lamb shift measurement and the best present value obtained from the elastic scattering experiments, remains unexplained and represents a burning problem of today’s nuclear physics: after more than 50 years of research the radius of a basic constituent of matter is still not understood. This paper presents a summary of the best existing proton radius measurements, followed by an overview of the possible explanations for the observed inconsistency between the hydrogen and the muonic-hydrogen data. In the last part the upcoming experiments, dedicated to remeasuring the proton radius, are described.

  5. Puzzling out the proton radius puzzle

    Energy Technology Data Exchange (ETDEWEB)

    Mihovilovič, M.; Merkel, H.; Weber, A. [Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, Johann-Joachim-Becher-Weg 45, 55128 Mainz (Germany)

    2016-01-22

    The discrepancy between the proton charge radius extracted from the muonic hydrogen Lamb shift measurement and the best present value obtained from the elastic scattering experiments, remains unexplained and represents a burning problem of today’s nuclear physics: after more than 50 years of research the radius of a basic constituent of matter is still not understood. This paper presents a summary of the best existing proton radius measurements, followed by an overview of the possible explanations for the observed inconsistency between the hydrogen and the muonic-hydrogen data. In the last part the upcoming experiments, dedicated to remeasuring the proton radius, are described.

  6. Visual Puzzles, Figure Weights, and Cancellation: Some Preliminary Hypotheses on the Functional and Neural Substrates of These Three New WAIS-IV Subtests.

    Science.gov (United States)

    McCrea, Simon M; Robinson, Thomas P

    2011-01-01

    In this study, five consecutive patients with focal strokes and/or cortical excisions were examined with the Wechsler Adult Intelligence Scale and Wechsler Memory Scale-Fourth Editions along with a comprehensive battery of other neuropsychological tasks. All five of the lesions were large and typically involved frontal, temporal, and/or parietal lobes and were lateralized to one hemisphere. The clinical case method was used to determine the cognitive neuropsychological correlates of mental rotation (Visual Puzzles), Piagetian balance beam (Figure Weights), and visual search (Cancellation) tasks. The pattern of results on Visual Puzzles and Figure Weights suggested that both subtests involve predominately right frontoparietal networks involved in visual working memory. It appeared that Visual Puzzles could also critically rely on the integrity of the left temporoparietal junction. The left temporoparietal junction could be involved in temporal ordering and integration of local elements into a nonverbal gestalt. In contrast, the Figure Weights task appears to critically involve the right temporoparietal junction involved in numerical magnitude estimation. Cancellation was sensitive to left frontotemporal lesions and not right posterior parietal lesions typical of other visual search tasks. In addition, the Cancellation subtest was sensitive to verbal search strategies and perhaps object-based attention demands, thereby constituting a unique task in comparison with previous visual search tasks.

  7. A Puzzle-Based Genetic Algorithm with Block Mining and Recombination Heuristic for the Traveling Salesman Problem

    Institute of Scientific and Technical Information of China (English)

    Pei-Chann Chang; Wei-Hsiu Huang; Zhen-Zhen Zhang

    2012-01-01

    In this research,we introduce a new heuristic approach using the concept of ant colony optimization (ACO)to extract patterns from the chromosomes generated by previous generations for solving the generalized traveling salesman problem.The proposed heuristic is composed of two phases.In the first phase the ACO technique is adopted to establish an archive consisting of a set of non-overlapping blocks and of a set of remaining cities (nodes) to be visited.The second phase is a block recombination phase where the set of blocks and the rest of cities are combined to form an artificial chromosome.The generated artificial chromosomes (ACs) will then be injected into a standard genetic algorithm (SGA) to speed up the convergence.The proposed method is called "Puzzle-Based Genetic Algorithm" or "p-ACGA".We demonstrate that p-ACGA performs very well on all TSPLIB problems,which have been solved to optimality by other researchers.The proposed approach can prevent the early convergence of the genetic algorithm (GA) and lead the algorithm to explore and exploit the search space by taking advantage of the artificial chromosomes.

  8. Black hole quasi-normal modes: the "electrons" of quantum gravity? Implications for the black hole information puzzle

    CERN Document Server

    Corda, Christian

    2015-01-01

    Some recent important results on black hole (BH) quantum physics concerning the BH effective state and the natural correspondence between Hawking radiation and BH quasi-normal modes (QNMs) are reviewed, clarified and refined. Such a correspondence permits to naturally interpret QNMs as quantum levels in a semi-classical model. This is a model of BH somewhat similar to the historical semi-classical model of the structure of a hydrogen atom introduced by Bohr in 1913. In a certain sense, QNMs represent the "electron" which jumps from a level to another one and the absolute values of the QNMs frequencies "triggered" by emissions (Hawking radiation) and absorption of particles represent the energy "shells" of the "gravitational hydrogen atom". Important consequences on the BH information puzzle are discussed. In fact, it is shown that the time evolution of this "Bohr-like BH model" obeys to a time dependent Schr\\"odinger equation which permits the final BH state to be a pure quantum state instead of a mixed one. ...

  9. Event-by-Event Hydrodynamics +Jet Energy Loss: A Solution to the RA A⊗v2 Puzzle

    Science.gov (United States)

    Noronha-Hostler, Jacquelyn; Betz, Barbara; Noronha, Jorge; Gyulassy, Miklos

    2016-06-01

    High pT>10 GeV elliptic flow, which is experimentally measured via the correlation between soft and hard hadrons, receives competing contributions from event-by-event fluctuations of the low-pT elliptic flow and event-plane angle fluctuations in the soft sector. In this Letter, a proper account of these event-by-event fluctuations in the soft sector, modeled via viscous hydrodynamics, is combined with a jet-energy-loss model to reveal that the positive contribution from low-pT v2 fluctuations overwhelms the negative contributions from event-plane fluctuations. This leads to an enhancement of high-pT>10 GeV elliptic flow in comparison to previous calculations and provides a natural solution to the decade-long high-pT RA A⊗v2 puzzle. We also present the first theoretical calculation of high-pT v3, which is shown to be compatible with current LHC data. Furthermore, we discuss how short-wavelength jet-medium physics can be deconvoluted from the physics of soft, bulk event-by-event flow observables using event-shape engineering techniques.

  10. The Puzzle of Italian Rice Origin and Evolution: Determining Genetic Divergence and Affinity of Rice Germplasm from Italy and Asia

    Science.gov (United States)

    Jiang, Zhuxi; Basso, Barbara; Sala, Francesco; Spada, Alberto; Grassi, Fabrizio; Lu, Bao-Rong

    2013-01-01

    The characterization of genetic divergence and relationships of a set of germplasm is essential for its efficient applications in crop breeding and understanding of the origin/evolution of crop varieties from a given geographical region. As the largest rice producing country in Europe, Italy holds rice germplasm with abundant genetic diversity. Although Italian rice varieties and the traditional ones in particular have played important roles in rice production and breeding, knowledge concerning the origin and evolution of Italian traditional varieties is still limited. To solve the puzzle of Italian rice origin, we characterized genetic divergence and relationships of 348 rice varieties from Italy and Asia based on the polymorphisms of microsatellite fingerprints. We also included common wild rice O. rufipogon as a reference in the characterization. Results indicated relatively rich genetic diversity (He = 0.63-0.65) in Italian rice varieties. Further analyses revealed a close genetic relationship of the Italian traditional varieties with those from northern China, which provides strong genetic evidence for tracing the possible origin of early established rice varieties in Italy. These findings have significant implications for the rice breeding programs, in which appropriate germplasm can be selected from a given region and utilized for transferring unique genetic traits based on its genetic diversity and evolutionary relationships. PMID:24265814

  11. Oil puzzle in Chinese stock market%中国股票市场的石油效应之谜

    Institute of Scientific and Technical Information of China (English)

    董坤; 谢海滨; 汪寿阳

    2012-01-01

    本文对股票市场是否具有可预测性进行探讨,通过石油价格的变动,进而预测上海证券交易所综合指数(SSEC)的收益率.检验结果显示,自2003年后,上证综指收益率存在显著的石油效应,这种中国所特有的石油效应之谜,既不能用有效市场假说来解释,也无法被信息反应不足假说所解释.%This paper reinvestigates the predictability of equity market index return of Chinese Shanghai Stock Exchange Composite index (SSEC) using the changes in oil prices. We find a significant oil effect on the predictability of SSEC returns after the year 2003. The effect can neither be explained by the efficient market hypothesis nor be explained by the information under-reaction hypothesis, which presents a Chinese oil puzzle.

  12. The puzzle of the 1996 Bárdarbunga, Iceland, earthquake: no volumetric component in the source mechanism

    Science.gov (United States)

    Tkalcic, Hrvoje; Dreger, Douglas S.; Foulger, Gillian R.; Julian, Bruce R.

    2009-01-01

    A volcanic earthquake with Mw 5.6 occurred beneath the Bárdarbunga caldera in Iceland on 29 September 1996. This earthquake is one of a decade-long sequence of  events at Bárdarbunga with non-double-couple mechanisms in the Global Centroid Moment Tensor catalog. Fortunately, it was recorded well by the regional-scale Iceland Hotspot Project seismic experiment. We investigated the event with a complete moment tensor inversion method using regional long-period seismic waveforms and a composite structural model. The moment tensor inversion using data from stations of the Iceland Hotspot Project yields a non-double-couple solution with a 67% vertically oriented compensated linear vector dipole component, a 32% double-couple component, and a statistically insignificant (2%) volumetric (isotropic) contraction. This indicates the absence of a net volumetric component, which is puzzling in the case of a large volcanic earthquake that apparently is not explained by shear slip on a planar fault. A possible volcanic mechanism that can produce an earthquake without a volumetric component involves two offset sources with similar but opposite volume changes. We show that although such a model cannot be ruled out, the circumstances under which it could happen are rare.

  13. Recovering the Genetic Identity of an Extinct-in-the-Wild Species: The Puzzling Case of the Alagoas Curassow

    Science.gov (United States)

    Costa, Mariellen C.; Oliveira, Paulo R. R.; Davanço, Paulo V.; de Camargo, Crisley; Laganaro, Natasha M.; Azeredo, Roberto A.; Simpson, James; Silveira, Luis F.

    2017-01-01

    The conservation of many endangered taxa relies on hybrid identification, and when hybrids become morphologically indistinguishable from the parental species, the use of molecular markers can assign individual admixture levels. Here, we present the puzzling case of the extinct in the wild Alagoas Curassow (Pauxi mitu), whose captive population descends from only three individuals. Hybridization with the Razor-billed Curassow (P. tuberosa) began more than eight generations ago, and admixture uncertainty affects the whole population. We applied an analysis framework that combined morphological diagnostic traits, Bayesian clustering analyses using 14 microsatellite loci, and mtDNA haplotypes to assess the ancestry of all individuals that were alive from 2008 to 2012. Simulated data revealed that our microsatellites could accurately assign an individual a hybrid origin until the second backcross generation, which permitted us to identify a pure group among the older, but still reproductive animals. No wild species has ever survived such a severe bottleneck, followed by hybridization, and studying the recovery capability of the selected pure Alagoas Curassow group might provide valuable insights into biological conservation theory. PMID:28056082

  14. The puzzle of Italian rice origin and evolution: determining genetic divergence and affinity of rice germplasm from Italy and Asia.

    Science.gov (United States)

    Cai, Xingxing; Fan, Jing; Jiang, Zhuxi; Basso, Barbara; Sala, Francesco; Spada, Alberto; Grassi, Fabrizio; Lu, Bao-Rong

    2013-01-01

    The characterization of genetic divergence and relationships of a set of germplasm is essential for its efficient applications in crop breeding and understanding of the origin/evolution of crop varieties from a given geographical region. As the largest rice producing country in Europe, Italy holds rice germplasm with abundant genetic diversity. Although Italian rice varieties and the traditional ones in particular have played important roles in rice production and breeding, knowledge concerning the origin and evolution of Italian traditional varieties is still limited. To solve the puzzle of Italian rice origin, we characterized genetic divergence and relationships of 348 rice varieties from Italy and Asia based on the polymorphisms of microsatellite fingerprints. We also included common wild rice O. rufipogon as a reference in the characterization. Results indicated relatively rich genetic diversity (H(e) = 0.63-0.65) in Italian rice varieties. Further analyses revealed a close genetic relationship of the Italian traditional varieties with those from northern China, which provides strong genetic evidence for tracing the possible origin of early established rice varieties in Italy. These findings have significant implications for the rice breeding programs, in which appropriate germplasm can be selected from a given region and utilized for transferring unique genetic traits based on its genetic diversity and evolutionary relationships.

  15. Recovering the Genetic Identity of an Extinct-in-the-Wild Species: The Puzzling Case of the Alagoas Curassow.

    Science.gov (United States)

    Costa, Mariellen C; Oliveira, Paulo R R; Davanço, Paulo V; Camargo, Crisley de; Laganaro, Natasha M; Azeredo, Roberto A; Simpson, James; Silveira, Luis F; Francisco, Mercival R

    2017-01-01

    The conservation of many endangered taxa relies on hybrid identification, and when hybrids become morphologically indistinguishable from the parental species, the use of molecular markers can assign individual admixture levels. Here, we present the puzzling case of the extinct in the wild Alagoas Curassow (Pauxi mitu), whose captive population descends from only three individuals. Hybridization with the Razor-billed Curassow (P. tuberosa) began more than eight generations ago, and admixture uncertainty affects the whole population. We applied an analysis framework that combined morphological diagnostic traits, Bayesian clustering analyses using 14 microsatellite loci, and mtDNA haplotypes to assess the ancestry of all individuals that were alive from 2008 to 2012. Simulated data revealed that our microsatellites could accurately assign an individual a hybrid origin until the second backcross generation, which permitted us to identify a pure group among the older, but still reproductive animals. No wild species has ever survived such a severe bottleneck, followed by hybridization, and studying the recovery capability of the selected pure Alagoas Curassow group might provide valuable insights into biological conservation theory.

  16. The puzzle of Italian rice origin and evolution: determining genetic divergence and affinity of rice germplasm from Italy and Asia.

    Directory of Open Access Journals (Sweden)

    Xingxing Cai

    Full Text Available The characterization of genetic divergence and relationships of a set of germplasm is essential for its efficient applications in crop breeding and understanding of the origin/evolution of crop varieties from a given geographical region. As the largest rice producing country in Europe, Italy holds rice germplasm with abundant genetic diversity. Although Italian rice varieties and the traditional ones in particular have played important roles in rice production and breeding, knowledge concerning the origin and evolution of Italian traditional varieties is still limited. To solve the puzzle of Italian rice origin, we characterized genetic divergence and relationships of 348 rice varieties from Italy and Asia based on the polymorphisms of microsatellite fingerprints. We also included common wild rice O. rufipogon as a reference in the characterization. Results indicated relatively rich genetic diversity (H(e = 0.63-0.65 in Italian rice varieties. Further analyses revealed a close genetic relationship of the Italian traditional varieties with those from northern China, which provides strong genetic evidence for tracing the possible origin of early established rice varieties in Italy. These findings have significant implications for the rice breeding programs, in which appropriate germplasm can be selected from a given region and utilized for transferring unique genetic traits based on its genetic diversity and evolutionary relationships.

  17. The Student Departure Puzzle: Do Some Faculties and Programs Have Answers?

    Science.gov (United States)

    Danaher, P. A.; Bowser, Don; Somasundaram, Jay

    2008-01-01

    University attrition prevention strategies are typically generic, centrally managed, whole of university strategies that have emerged from an examination of whole of university attrition data. This paper takes an intra-organisational comparative approach, through the examination of faculty and program attrition rates of students who joined an…

  18. The Effect of Drill and Practice Software on Multiplication Skills: "Multiplication Puzzles" versus "The Mad Minute."

    Science.gov (United States)

    Williams, Lynda Patterson

    The purpose of the study was to compare two methods of learning multiplication facts in order to develop speed and accuracy. The researcher conducted the action research project with a seventh grade enrichment class, which met for seven weeks during the school year. As part of the curriculum students were provided with activities to refine their…

  19. Why do humans deteriorate with age? It’s a biological puzzle

    DEFF Research Database (Denmark)

    Jones, Owen

    2014-01-01

    Some species live for a very long time, others more fleeting. Bristlecone pines have remarkable life spans of around 5,000 years and in the animal kingdom, creatures like elephants, whales and tortoises are comparatively long lived. Some of these even achieve individual fame; Harriet, one of the ...

  20. Puzzling Findings in Studying the Outcome of "Real World" Adolescent Mental Health Services: The TRAILS Study

    NARCIS (Netherlands)

    F. Jörg (Frederike); J. Ormel (Johan Hans); S.A. Reijneveld (Sijmen); D.E.M.C. Jansen (Daniëlle); F.C. Verhulst (Frank); A.J. Oldehinkel (Albertine)

    2012-01-01

    textabstractBackground: The increased use and costs of specialist child and adolescent mental health services (MHS) urge us to assess the effectiveness of these services. The aim of this paper is to compare the course of emotional and behavioural problems in adolescents with and without MHS use in a

  1. AMBITION: An important piece in the therapeutic puzzle of pulmonary arterial hypertension.

    Science.gov (United States)

    Said, Karim

    2015-01-01

    It is believed that simultaneous targeting of two or more of the three pathogenic pathways of pulmonary arterial hypertension (the endothelin, nitric oxide, and prostacyclin pathways) is associated with additive or synergistic effects with subsequent increasing efficacy and improving outcomes. However, there is lack of evidence to guide the use of combination strategy among pulmonary arterial hypertension patients and many questions remain to be answered. One of these vital questions is whether the strategy of upfront initiation of combination therapy could improve patients outcomes compared to the strategy of initial monotherapy. The recently published AMBITION trial represents an important forward step towards answering this question by comparing a strategy of first-line combination therapy (ambrisentan and tadalafil) versus first-line monotherapy (ambrisentan or tadalafil) in patients with pulmonary arterial hypertension.

  2. Extracting the Gluon Piece of the Spin Puzzle: New Inclusive Jet Results from STAR

    CERN Document Server

    Fatemi, Renee

    2007-01-01

    This contribution presents the most recent mid-rapidity inclusive jet results from 3 pb^-1 of data collected from longitudinally polarized proton collisions at sqrt(s)=200 GeV during the 2005 RHIC run. The inclusive jet asymmetry, a_LL, with it's increased transverse momentum range and precision, provides strong constraints on the gluon helicity distribution when compared with existing next-to-leading order perturbative QCD evaluations.

  3. Emotional intelligence in anorexia nervosa: is anxiety a missing piece of the puzzle?

    Science.gov (United States)

    Hambrook, David; Brown, Gary; Tchanturia, Kate

    2012-11-30

    Problematic emotional processing has been implicated in the genesis and maintenance of anorexia nervosa (AN). This study built on existing research and explored performance-based emotional intelligence (EI) in people with AN. The Mayer-Salovey-Caruso Emotional Intelligence Test (MSCEIT) was administered to 32 women diagnosed with AN and 32 female healthy controls (HC). Compared to HC women, the AN group demonstrated significantly lower total EI scores and poorer ability to understand how emotions can progress and change over time. Despite scores within the broadly average range compared to published EI norms, there was a general pattern of poorer performance in the AN sample. Self-reported anxiety symptoms were the strongest predictor of EI, over and above a diagnosis of AN. This study adds to the literature documenting the socioemotional phenotype of AN, suggesting this group of individuals may find it relatively difficult to carry out accurate reasoning about emotions, and to use emotions and emotional knowledge to enhance thought. Anxiety was highlighted as a putative variable partially explaining why people with AN demonstrated lower EI compared to controls. Implications for further research are discussed, including the need to explore the specificity of EI difficulties in AN using larger samples and additional control groups.

  4. Large-scale impacts of multiple co-occurring invaders on monkey puzzle forest regeneration, native seed predators and their ecological interactions

    Directory of Open Access Journals (Sweden)

    José L. Tella

    2016-04-01

    Full Text Available Most ecosystems of the world are being increasingly invaded by a variety of alien species. However, little is known about the combined ecological impacts of multiple co-occurring invaders. We assessed the impact of a community of exotic mammals (five domestic and four wild on forests of monkey puzzle (Araucaria araucana, a globally endangered tree restricted to ca 400 km2 on the slopes of the Andes in Chile and Argentina. Seeds of monkey puzzles provide food during winter to a small community of native mice and Austral parakeets (Enicognathus ferrugineus. We recorded the number of uneaten seeds and the number of young seedlings at the end of winter under 516 female monkey puzzle trees located across the species’ distribution, and identified the signals of native and exotic species that visited the under-canopy of each tree. Moreover, we studied the diet and foraging behavior of Austral parakeets to explore the potential indirect effects of exotic mammals through the disruption of a key ecosystem service (seed dispersal supposedly provided by parakeets. All but one tree were visited by at least one seed predator species. Austral parakeets and mice predated seeds from 85% and at least 45% of the trees, respectively, and both the number of remaining seeds and seedlings were significantly larger when only parakeets or mice predated seeds than when exotic mammals also visited the trees. At least 90% of trees were visited by one or more exotic species, and the number of seeds and seedlings dropped drastically when at least two and four exotic species visited the tree, respectively. Austral parakeets mostly foraged on monkey puzzle trees during the winter period and dispersed their seeds in most feeding instances once seeds fell to the ground. The proliferation of exotic mammals may reduce the populations of native seed-predators in the long-term as well as the regeneration of monkey puzzle forests, directly through a reduction of seed availability

  5. 基于"挖洞"思想的数独游戏生成算法%Sudoku Puzzles Generating:From Easy to Evil

    Institute of Scientific and Technical Information of China (English)

    薛源海; 蒋彪彬; 李永卓

    2009-01-01

    Sudoku puzzle becomes worldwide popular among many players in different intellectual levels. The task is to devise an algorithm that creates Sudoku puzzles in varying level of difficulty. With the analysis of the game rules, we first define the difficulty level from four aspects as: total given cells, distribution of given cells and complexity of enumerating search. By the guidance from the definition of difficulty level, the algorithm for generating puzzles is developed with the "dig-hole" strategy on a valid grid. Thus, the algorithm developed in two steps: to create a valid grid by Las Vegas algorithm, and then to generating puzzles by erasing some digits using five operators : · Determine a sequence of digging holes according to the desirable difficulty level, · Set two restrictions to guide the distribution of given cells, · Judge whether a puzzle being dug out has a unique solution by a solver built using Depth-First Search, · Add pruning technique to avoid digging an invalid cell, and · Perform propagating at a dug-out puzzle to raise the diversity of the output puzzle. Using our developed algorithm, we generate Sudoku puzzles in any five difficulty levels.The difficulty level of output puzzles can be adjusted by a desirable difficulty value input by players. The complexity of the algorithms in space and time is analyzed to demonstrate the effectiveness of the algorithms. Our main contributions in exploring the "dig-hole" strategy are summarized as following three works: to do a massive research on the sequence of digging holes and how it affects the algorithm to create a evil-level puzzle with minimal given cells, to invent a skill for judging the solution's uniqueness of a puzzle being dug out by the reduction to absurdity, and to reduce the computational time by avoiding backtracking to an explored cell and refilling an empty cell.%设计一个算法用以生成各种难度等级的数独题,通过对游戏规则的分析,首先从以下三个方面

  6. Vascular function long term after Kawasaki disease: another piece of the puzzle?

    Science.gov (United States)

    Pinto, Fátima F; Gomes, Inês; Loureiro, Petra; Laranjo, Sérgio; Timóteo, Ana T; Carmo, Miguel M

    2017-04-01

    Kawasaki disease is an acute systemic vasculitis. Cardiac complications are frequent and include endothelial dysfunction in patients with coronary anomalies. Thus far, endothelial dysfunction in patients with no coronary lesions is poorly understood. Our aim was to access the vascular function in adolescents and young adults long term after Kawasaki disease, but without coronary aneurysms or any other cardiac risk factors. We carried out a single-centre prospective study in a Portuguese population. We evaluated two groups of subjects: (1) Kawasaki disease patients over 11 years of age, diagnosed >5 years ago, with no coronary lesions or any other risk factors for cardiovascular disease; (2) control group of individuals without cardiovascular risk factors. Patients and controls were clinically assessed. Endo-PAT and carotid intima-media thickness assessment were performed to determine vascular function. In total, 43 Kawasaki disease patients were assessed and compared with 43 controls. Kawasaki disease patients presented a decreased reactive hyperaemia index compared with controls (1.59±0.45 versus 1.98±0.41; pKawasaki disease group. There were no statistically significant changes with regard to laboratory data. Children with Kawasaki disease may have long-term sequelae, even when there is no discernible coronary artery involvement in the acute stage of the disease. Further research is needed to assess whether known strategies to improve endothelial function would bring potential benefits to Kawasaki disease patients.

  7. THE PUZZLING MUTUAL ORBIT OF THE BINARY TROJAN ASTEROID (624) HEKTOR

    Energy Technology Data Exchange (ETDEWEB)

    Marchis, F.; Cuk, M. [Carl Sagan Center at the SETI Institute, Mountain View, CA 94043 (United States); Durech, J. [Astronomical Institute, Faculty of Mathematics and Physics, Charles University, Prague (Czech Republic); Castillo-Rogez, J. [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 (United States); Vachier, F.; Berthier, J. [IMCCE-Obs de Paris, F-75014 Paris (France); Wong, M. H.; Kalas, P.; Duchene, G. [Department of Astronomy, University of California at Berkeley, Berkeley, CA 94720 (United States); Van Dam, M. A. [Flat Wavefronts, Christchurch 8140 (New Zealand); Hamanowa, H. [Hamanowa Observatory, Motomiya, Fukushima 969-1204 (Japan); Viikinkoski, M., E-mail: fmarchis@seti.org [Tampere University of Technology, FI-33101 Tampere (Finland)

    2014-03-10

    Asteroids with satellites are natural laboratories to constrain the formation and evolution of our solar system. The binary Trojan asteroid (624) Hektor is the only known Trojan asteroid to possess a small satellite. Based on W. M. Keck adaptive optics observations, we found a unique and stable orbital solution, which is uncommon in comparison to the orbits of other large multiple asteroid systems studied so far. From lightcurve observations recorded since 1957, we showed that because the large Req = 125 km primary may be made of two joint lobes, the moon could be ejecta of the low-velocity encounter, which formed the system. The inferred density of Hektor's system is comparable to the L5 Trojan doublet (617) Patroclus but due to their difference in physical properties and in reflectance spectra, both captured Trojan asteroids could have a different composition and origin.

  8. Maternal Obesity and Impaired Fetal and Infant Survival-One More Piece Added to the Puzzle

    DEFF Research Database (Denmark)

    Nohr, Ellen A

    2016-01-01

    The association between maternal obesity and increased risks of stillbirth and infant mortality is well documented, but it has often been questioned whether the association is driven by obesity per se or by unmeasured factors such as insulin resistance or genes. In this issue of the Journal, Lindam...... et al. compared the body mass indices (weight (kg)/height (m)(2)) of women who had stillbirths and infant deaths with those of their sisters or of population controls. Significant excess risks of both outcomes were observed in obese women (body mass index ≥30), and associations were strongest when...... sister controls were used. Although this careful analysis adds to the existing evidence of a causal relationship between maternal obesity and impaired fetal and infant survival, a biological pathway has not yet been established. Additionally, we are in urgent need of effective tools to reduce obesity...

  9. Solving the missing GRB neutrinos and the GRB-SN puzzles

    CERN Document Server

    Fargion, Daniele

    2016-01-01

    We argue that any GRB model where the progenitor is made by high relativistic hadronic interactions shock waves, and later on by electron-pairs feeding gamma jets, is necessarily leading to an average high neutrino over photon fluency ratio well above unity, mostly above several thousands. The present observed average highest energy ICECUBE neutrino energy fluency is at most comparable to the gamma-X in GRB one. Therefore no hadronic GRB, Fireball or even any earliest hadronic thin precessing Jet, may fit the observation. We therefore imagine a novel electronic thin spinning and precessing jet, fed in late binary system, able to avoid the overcrowded neutrino tails foreseen in hadronic GRB models. In some occasion such an electronic model may lead to an explosion that shines during a GRB with an (apparent) late SN-like event.

  10. The puzzling theoretical predictions for the luminosity of clumping He burning stars

    CERN Document Server

    Castellani, V; Girardi, L; Marconi, M; Moroni, P G P; Weiss, A

    1999-01-01

    This paper deals with theoretical predictions for He burning models in a range of masses covering the so-called Red Giant Branch phase transition. Taking as a guideline the observational constraints given by Hipparcos parallaxes to the predicted luminosity of models originated from Red Giant progenitors with He core undergoing electron degeneracy, we compare models by various authors as recently appeared in the literature, disclosing sensitive differences in the predicted luminosity. The solidity of these theoretical predictions is investigated by exploring the effects of varying the assumptions about the efficiency of core overshooting or the amount of mass loss, giving quantitative estimates of the related uncertainties. However, one finds that theoretical predictions concerning the luminosity of the red giant clump in the Hipparcos sample is scarcely affected by these mechanisms.A comparison among theoretical predictions as recently given by different authors convincingly demonstrates that the different lu...

  11. Radii and binding energies in oxygen isotopes: a puzzle for nuclear forces

    CERN Document Server

    Lapoux, V; Barbieri, C; Hergert, H; Holt, J D; Stroberg, R

    2016-01-01

    We present a systematic study of both nuclear radii and binding energies in (even) oxygen isotopes from the valley of stability to the neutron drip line. Both charge and matter radii are compared to state-of-the-art {\\it ab initio} calculations along with binding energy systematics. Experimental matter radii are obtained through a complete evaluation of the available elastic proton scattering data of oxygen isotopes. We show that, in spite of a good reproduction of binding energies, {\\it ab initio} calculations with conventional nuclear interactions derived within chiral effective field theory fail to provide a realistic description of charge and matter radii. A novel version of two- and three-nucleon forces leads to considerable improvement of the simultaneous description of the three observables for stable isotopes, but shows deficiencies for the most neutron-rich systems. Thus, crucial challenges related to the development of nuclear interactions remain.

  12. Structure, dynamics and function of Leishmania genome: resolving the puzzle of infection, genetics and evolution?

    Science.gov (United States)

    Dujardin, Jean-Claude

    2009-03-01

    We review and discuss here the specificity and contribution of genome (re-)arrangement studies for the exploration of genetic diversity among Leishmania. We show how the early molecular karyotyping studies generated an original perception of the genetics and evolution of these Protozoa, while providing some possible explanations on the parasite diverse phenotypes (drug resistance, pathogenicity...). We compare the results with the enormous amount of data provided by the recent genome sequencing projects, so far focused on one strain per genus/species. We highlight the relevance of parallel sequencing of different strains of a same species, now made possible by the new sequencing technologies. We recommend paying a particular attention to variation in gene copy number, a feature showed by the karyotyping studies to be extremely informative.

  13. A deficit in optimizing task solution but robust and well-retained speed and accuracy gains in complex skill acquisition in Parkinson׳s disease: multi-session training on the Tower of Hanoi Puzzle.

    Science.gov (United States)

    Vakil, Eli; Hassin-Baer, Sharon; Karni, Avi

    2014-05-01

    There are inconsistent results in the research literature relating to whether a procedural memory dysfunction exists as a core deficit in Parkinson׳s disease (PD). To address this issue, we examined the acquisition and long-term retention of a cognitive skill in patients with moderately severe PD. To this end, we used a computerized version of the Tower of Hanoi Puzzle. Sixteen patients with PD (11 males, age 60.9±10.26 years, education 13.8±3.5 years, disease duration 8.6±4.7 years, UPDRS III "On" score 16±5.3) were compared with 20 healthy individuals matched for age, gender, education and MMSE scores. The patients were assessed while taking their anti-Parkinsonian medication. All participants underwent three consecutive practice sessions, 24-48h apart, and a retention-test session six months later. A computerized version of the Tower of Hanoi Puzzle, with four disks, was used for training. Participants completed the task 18 times in each session. Number of moves (Nom) to solution, and time per move (Tpm), were used as measures of acquisition and retention of the learned skill. Robust learning, a significant reduction in Nom and a concurrent decrease in Tpm, were found across all three training sessions, in both groups. Moreover, both patients and controls showed significant savings for both measures at six months post-training. However, while their Tpm was no slower than that of controls, patients with PD required more Nom (in 3rd and 4th sessions) and tended to stabilize on less-than-optimal solutions. The results do not support the notion of a core deficit in gaining speed (fluency) or generating procedural memory in PD. However, PD patients settled on less-than-optimal solutions of the task, i.e., less efficient task solving process. The results are consistent with animal studies of the effects of dopamine depletion on task exploration. Thus, patients with PD may have a problem in exploring for optimal task solution rather than in skill acquisition and

  14. APRENDER JUGANDO CON "TEJIDOS PRECOLOMBINOS" MEDIANTE ROMPECABEZAS VIRTUALES LEARN BY PLAYING WITH "PRE-COLUMBIAN TEXTILES" THROUGH VIRTUAL PUZZLES

    Directory of Open Access Journals (Sweden)

    Diego Aracena Pizarro

    2008-09-01

    Full Text Available Este trabajo presenta un ambiente multimedia de rompecabezas sobre tejidos precolombinos de gran complejidad ornamental, expuestos en el Museo Arqueológico San Miguel de Azapa, Arica-Chile. El rompecabezas permite interaccionar de manera más entretenida y didáctica, con el objetivo de que la facilidad del uso del software permita aprender jugando, observando los intrincados símbolos y signos precolombinos que de otra manera pasan desapercibidos por no formar parte del ideario de los estudiantes actuales. El software se evaluó con alumnos de enseñanza básica y media de establecimientos educacionales de la ciudad, con el objetivo de complementar sus estudios a las asignaturas de historia que contienen temática prehispánica. Esta representación educacional fue implementada con herramienta Flash multimedia, con el propósito de estimular la parte creativa de los estudiantes y de abrir un mundo de juegos complementarios referentes al mismo tema, con la filosofía de aprender jugando.This paper presents a multimedia environment puzzle about Pre-Columbian textiles exhibiting ornamental complexities, found in the Archeological Museum San Miguel de Azapa, Arica-Chile. The software allow for an enjoyable and didactic interactive way of learning by playing, giving the users the opportunity of identifying intricate pre-Columbian symbols and signals, that otherwise would be unnoticed. The software was tested with schoolboys of ages 12 to 16 years old, from schools in Arica, with the purpose of complementing their studies in History courses containing Pre-hispanic topics. This educational software was implemented with Multimedia Flash Tool, so as to stimulate the creativity of the students, opening a world of complementary games with the philosophy of "learning by playing".

  15. PENGEMBANGAN PENCEGAHAN SERANGAN DISTRIBUTED DENIAL OF SERVICE (DDOS PADA SUMBER DAYA JARINGAN DENGAN INTEGRASI NETWORK BEHAVIOR ANALYSIS DAN CLIENT PUZZLE

    Directory of Open Access Journals (Sweden)

    Septian Geges

    2015-01-01

    Full Text Available Denial of Service (DoS merupakan permasalahan keamanan jaringan yang sampai saat ini terus berkembang secara dinamis. Semakin tinggi kemampuan komputasi suatu komputer penyerang, serangan DoS yang dapat dihasilkan juga semakin membahayakan. Serangan ini dapat mengakibatkan ketidakmampuan server untuk melayani service request yang sah. Karena itu serangan DoS sangat merugikan dan perlu diberikan pencegahan yang efektif. Ancaman berikutnya yang juga sangat membahayakan adalah Distributed Denial of Service (DDoS, dimana serangan ini memanfaatkan sejumlah besar komputer untuk menjalankan serangan DoS kepada server, web service, atau sumber daya jaringan lain. Mengingat resiko besar yang diakibatkan serangan DDoS ini, banyak peneliti yang terdorong untuk merancang mekanisme penga-manan sumber daya jaringan. Pada penelitian ini, penulis mengkhususkan pokok permasalahan pada pengamanan web service. Penulis mengemuka-kan sebuah mekanisme untuk mengamankan web service dengan cara melakukan filtrasi dan validasi permintaan yang diterima untuk mengakses sumber daya jaringan. Filtrasi dan validasi ini dilakukan dengan gabungan metode Network Behavior Analysis (NBA dan Client Puzzle (CP. Metode NBA menjadi lapisan pertahanan pertama untuk mendeteksi apakah sedang terjadi serangan DDoS dengan mengukur tingkat kepadatan jaringan/Network density. Dari metode NBA, didapatkan IP Address yang perlu divalidasi dengan metode CP sebagai lapisan pertahanan kedua. Apabila suatu service request sudah berhasil melewati proses filtrasi dan validasi ini, maka service request ini baru akan dilayani. Dari hasil percobaan, terbukti metode ini dapat mendeteksi serangan DDoS sekaligus menjamin bahwa service request yang sah mendapat pelayanan yang seharusnya sehingga server dapat melayani service request dengan baik.

  16. Hospital Compare

    Data.gov (United States)

    U.S. Department of Health & Human Services — Hospital Compare has information about the quality of care at over 4,000 Medicare-certified hospitals across the country. You can use Hospital Compare to find...

  17. The conundrum of Greece and the Eurozone: Puzzles, paradoxes and contradictions

    Directory of Open Access Journals (Sweden)

    Kitromilides Yiannis

    2016-01-01

    Full Text Available This paper examines three questions regarding the controversial relationship between Greece and the eurozone during the current crisis. First, why was Greece “bailed-out” in 2010? Second, why the Greek economy collapsed despite the largest “bail-out” in global financial history? Third, was the electoral mandate of the Syriza government for ending austerity while remaining in the eurozone contradictory? There are conflicting answers to all three questions and the paper compares the answers of the so called “dominant narrative” to those provided by the “counter-narrative” of the eurozone crisis. The paper reaches the following conclusions. First, the primary motivation for the “bail-out” of Greece was the maintenance of European and global financial stability. Second, although programme implementation was less successful in Greece than in other “programme” countries the catastrophic collapse of the Greek economy had more to do with the programme itself than its implementation. Third, the meaning of democratic decision-making in the Euro-group needs re-appraisal and must go beyond seeing the Greek demand of a policy reversal in the eurozone as simply a clash of democratic mandates in a 19 member monetary union. Political unity will not only improve efficiency but also democracy and accountability in eurozone policymaking.

  18. Assembling a puzzle of dispersed retrotransposable sequences in the genome of chickpea (Cicer arietinum L.).

    Science.gov (United States)

    Staginnus, C; Desel, C; Schmidt, T; Kahl, G

    2010-12-01

    Several repetitive elements are known to be present in the genome of chickpea (Cicer arietinum L.) including satellite DNA and En/Spm transposons as well as two dispersed, highly repetitive elements, CaRep1 and CaRep2. PCR was used to prove that CaRep1, CaRep2, and previously isolated CaRep3 of C. arietinum represent different segments of a highly repetitive Ty3-gypsy-like retrotransposon (Metaviridae) designated CaRep that makes up large parts of the intercalary heterochromatin. The full sequence of this element including the LTRs and untranslated internal regions was isolated by selective amplification. The restriction pattern of CaRep was different within the annual species of the genus Cicer, suggesting its rearrangement during the evolution of the genus during the last 100 000 years. In addition to CaRep, another LTR and a non-LTR retrotransposon family were isolated, and their restriction patterns and physical localization in the chickpea genome were characterized. The LINE-like element CaLin is only of comparatively low abundance and reveals a considerable heterogeneity. The Ty1-copia-like element (Pseudoviridae) CaTy is located in the distal parts of the intercalary heterochromatin and adjacent euchromatic regions, but it is absent from the centromeric regions. These results together with earlier findings allow to depict the distribution of retroelements on chickpea chromosomes, which extensively resembles the retroelement landscape of the genome of the model legume Medicago truncatula Gaertn.

  19. The attribute of rotational profile to the hyperon puzzle in the prediction of heaviest compact star

    CERN Document Server

    Bhuyan, M

    2016-01-01

    In this theoretical study, we report an investigation of the equations of state (EoSs) of hyper-nuclear matter and its composition as a function of density within the framework of effective field theory motivated relativistic mean field model. We have used G2 force parameter along with various hyperon-meson coupling ratios by allowing the mixing and the breaking of SU(6) symmetry to predict the EoSs, keeping the nucleonic coupling constant intact. We have estimated the properties of non-rotating and rapidly rotating configuration of compact stars by employing a representative set of equations of state. The obtained results of the mass M$_{\\odot}$ and radius R$_{\\odot}$ for the compact stars are compared with the recent mass observations. We noticed that the inclusion of hyperon matter to the EoSs of nuclear matter under $\\beta$-equilibrium condition decreases the maximum mass of the compact star by $0.4$ unit in magnitude in comparison to the nuclear matter prediction. Further, we have studied the stability a...

  20. Incidence of MgII absorbers towards Blazars and the GRB/QSO puzzle

    CERN Document Server

    Bergeron, Jacqueline; Ménard, Brice

    2010-01-01

    In order to investigate the origin of the excess of strong MgII systems towards GRB afterglows as compared to QSO sightlines, we have measured the incidence of MgII absorbers towards a third class of objects: the Blazars. This class includes the BL Lac object population for which a tentative excess of MgII systems had already been reported. We observed with FORS1 at the ESO-VLT 42 Blazars with an emission redshift 0.8 1.0 A) and weaker (0.3 < w_r(2796) < 1.0 A) MgII systems. The dependence on velocity separation with respect to the background Blazars indicates, at the ~1.5 sigma level, a potential excess for beta = v/c ~0.1. We show that biases involving dust extinction or gravitational amplification are not likely to notably affect the incidence of MgII systems towards Blazars. Finally we discuss the physical conditions required for these absorbers to be ga s entrained by the powerful Blazar jets. More realistic numerical modelling of jet-ambient gas interaction is required to reach any firm conclusion...

  1. The puzzle of the CNO isotope ratios in AGB carbon stars

    CERN Document Server

    Abia, Carlos; Domínguez, Inma; Straniero, Oscar

    2016-01-01

    Previous determinations of the oxygen isotopic ratios in AGB carbon stars were at odds with the existing theoretical predictions. We aim to redetermine the oxygen ratios in these stars using new spectral analysis tools and further develop discussions on the carbon and nitrogen isotopic ratios in order to elucidate this problem. Oxygen isotopic ratios were derived from spectra in the K-band in a sample of galactic AGB carbon stars of different spectral types and near solar metallicity. Synthetic spectra calculated in LTE with spherical carbon-rich atmosphere models and updated molecular line lists were used. The CNO isotope ratios derived in a homogeneous way, were compared with theoretical predictions for low-mass (1.5-3 M_o) AGB stars computed with the FUNS code assuming extra mixing both during the RGB and AGB phases. For most of the stars the 16O/17O/18O ratios derived are in good agreement with theoretical predictions confirming that, for AGB stars, are established using the values reached after the FDU a...

  2. Arthropod Distribution in a Tropical Rainforest: Tackling a Four Dimensional Puzzle

    Science.gov (United States)

    Basset, Yves; Cizek, Lukas; Cuénoud, Philippe; Didham, Raphael K.; Novotny, Vojtech; Ødegaard, Frode; Roslin, Tomas; Tishechkin, Alexey K.; Schmidl, Jürgen; Winchester, Neville N.; Roubik, David W.; Aberlenc, Henri-Pierre; Bail, Johannes; Barrios, Héctor; Bridle, Jonathan R.; Castaño-Meneses, Gabriela; Corbara, Bruno; Curletti, Gianfranco; Duarte da Rocha, Wesley; De Bakker, Domir; Delabie, Jacques H. C.; Dejean, Alain; Fagan, Laura L.; Floren, Andreas; Kitching, Roger L.; Medianero, Enrique; Gama de Oliveira, Evandro; Orivel, Jérôme; Pollet, Marc; Rapp, Mathieu; Ribeiro, Sérvio P.; Roisin, Yves; Schmidt, Jesper B.; Sørensen, Line; Lewinsohn, Thomas M.; Leponce, Maurice

    2015-01-01

    Quantifying the spatio-temporal distribution of arthropods in tropical rainforests represents a first step towards scrutinizing the global distribution of biodiversity on Earth. To date most studies have focused on narrow taxonomic groups or lack a design that allows partitioning of the components of diversity. Here, we consider an exceptionally large dataset (113,952 individuals representing 5,858 species), obtained from the San Lorenzo forest in Panama, where the phylogenetic breadth of arthropod taxa was surveyed using 14 protocols targeting the soil, litter, understory, lower and upper canopy habitats, replicated across seasons in 2003 and 2004. This dataset is used to explore the relative influence of horizontal, vertical and seasonal drivers of arthropod distribution in this forest. We considered arthropod abundance, observed and estimated species richness, additive decomposition of species richness, multiplicative partitioning of species diversity, variation in species composition, species turnover and guild structure as components of diversity. At the scale of our study (2km of distance, 40m in height and 400 days), the effects related to the vertical and seasonal dimensions were most important. Most adult arthropods were collected from the soil/litter or the upper canopy and species richness was highest in the canopy. We compared the distribution of arthropods and trees within our study system. Effects related to the seasonal dimension were stronger for arthropods than for trees. We conclude that: (1) models of beta diversity developed for tropical trees are unlikely to be applicable to tropical arthropods; (2) it is imperative that estimates of global biodiversity derived from mass collecting of arthropods in tropical rainforests embrace the strong vertical and seasonal partitioning observed here; and (3) given the high species turnover observed between seasons, global climate change may have severe consequences for rainforest arthropods. PMID:26633187

  3. Arthropod Distribution in a Tropical Rainforest: Tackling a Four Dimensional Puzzle.

    Directory of Open Access Journals (Sweden)

    Yves Basset

    Full Text Available Quantifying the spatio-temporal distribution of arthropods in tropical rainforests represents a first step towards scrutinizing the global distribution of biodiversity on Earth. To date most studies have focused on narrow taxonomic groups or lack a design that allows partitioning of the components of diversity. Here, we consider an exceptionally large dataset (113,952 individuals representing 5,858 species, obtained from the San Lorenzo forest in Panama, where the phylogenetic breadth of arthropod taxa was surveyed using 14 protocols targeting the soil, litter, understory, lower and upper canopy habitats, replicated across seasons in 2003 and 2004. This dataset is used to explore the relative influence of horizontal, vertical and seasonal drivers of arthropod distribution in this forest. We considered arthropod abundance, observed and estimated species richness, additive decomposition of species richness, multiplicative partitioning of species diversity, variation in species composition, species turnover and guild structure as components of diversity. At the scale of our study (2 km of distance, 40 m in height and 400 days, the effects related to the vertical and seasonal dimensions were most important. Most adult arthropods were collected from the soil/litter or the upper canopy and species richness was highest in the canopy. We compared the distribution of arthropods and trees within our study system. Effects related to the seasonal dimension were stronger for arthropods than for trees. We conclude that: (1 models of beta diversity developed for tropical trees are unlikely to be applicable to tropical arthropods; (2 it is imperative that estimates of global biodiversity derived from mass collecting of arthropods in tropical rainforests embrace the strong vertical and seasonal partitioning observed here; and (3 given the high species turnover observed between seasons, global climate change may have severe consequences for rainforest arthropods.

  4. Active galactic nucleus torus models and the puzzling infrared spectrum of IRAS F10214+4724

    Science.gov (United States)

    Efstathiou, A.; Christopher, N.; Verma, A.; Siebenmorgen, R.

    2013-12-01

    We present a revised model for the infrared emission of the hyperluminous infrared galaxy IRAS F10214+4724 which takes into account recent photometric data from Spitzer and Herschel that sample the peak of its spectral energy distribution. We first present and discuss a grid of smooth active galactic nucleus (AGN) torus models computed with the method of Efstathiou & Rowan-Robinson and demonstrate that the combination of these models and the starburst models of Efstathiou and coworkers, while able to give an excellent fit to the average spectrum of Seyfert 2s and spectra of individual type 2 quasars measured by Spitzer, fails to match the spectral energy distribution of IRAS F10214+4724. This is mainly due to the fact that the νSν distribution of the galaxy falls very steeply with increasing frequency (a characteristic that is usually indicative of heavy absorption by dust) but shows a silicate feature in emission. Such emission features are not expected in sources with optical/near-infrared type 2 AGN spectral signatures. The Herschel data show that there is more power emitted in the rest-frame 20-50 μm wavelength range compared with the model presented by Efstathiou which assumes three components of emission: an edge-on torus, clouds (at a temperature of 610 and 200 K) that are associated with the narrow-line region (NLR) and a highly obscured starburst that dominates in the submillimetre. We present a revised version of that model that assumes an additional component of emission which we associate with NLR clouds at a temperature of 100 K. The 100 K dust component could also be explained by a highly obscured hot starburst. The model suggests that the NLR of IRAS F10214+4724 has an unusually high covering factor (≥17 per cent) or more likely the magnification of the emission from the NLR clouds is significantly higher than that of the emission from the torus.

  5. The jigsaw puzzle of sequence phenotype inference: Piecing together Shannon entropy, importance sampling, and Empirical Bayes.

    Science.gov (United States)

    Shreif, Zeina; Striegel, Deborah A; Periwal, Vipul

    2015-09-07

    A nucleotide sequence 35 base pairs long can take 1,180,591,620,717,411,303,424 possible values. An example of systems biology datasets, protein binding microarrays, contain activity data from about 40,000 such sequences. The discrepancy between the number of possible configurations and the available activities is enormous. Thus, albeit that systems biology datasets are large in absolute terms, they oftentimes require methods developed for rare events due to the combinatorial increase in the number of possible configurations of biological systems. A plethora of techniques for handling large datasets, such as Empirical Bayes, or rare events, such as importance sampling, have been developed in the literature, but these cannot always be simultaneously utilized. Here we introduce a principled approach to Empirical Bayes based on importance sampling, information theory, and theoretical physics in the general context of sequence phenotype model induction. We present the analytical calculations that underlie our approach. We demonstrate the computational efficiency of the approach on concrete examples, and demonstrate its efficacy by applying the theory to publicly available protein binding microarray transcription factor datasets and to data on synthetic cAMP-regulated enhancer sequences. As further demonstrations, we find transcription factor binding motifs, predict the activity of new sequences and extract the locations of transcription factor binding sites. In summary, we present a novel method that is efficient (requiring minimal computational time and reasonable amounts of memory), has high predictive power that is comparable with that of models with hundreds of parameters, and has a limited number of optimized parameters, proportional to the sequence length.

  6. The puzzle posed by COMMD1, a newly discovered protein binding Cu(II).

    Science.gov (United States)

    Sarkar, Bibudhendra; Roberts, Eve A

    2011-01-01

    Copper is critically important for cellular metabolism. It plays essential roles in developmental processes, including angiogenesis. The liver is central to mammalian copper homeostasis: biliary excretion is the major route of excretion for ingested copper and serves to regulate the total amount of copper in the organism. An extensive network of proteins manipulates copper disposition in hepatocytes, but comparatively little is known about this protein system. Copper exists in two oxidation states: most extracellular copper is Cu(II) and most, if not all, intracellular copper is Cu(I). Typical intracellular copper-binding proteins, such as the Cu-transporting P-type ATPases ATP7B (Wilson ATPase) and ATP7A (Menkes ATPase), bind copper as Cu(I). Accordingly, the recent discovery that the ubiquitous protein COMMD1 binds Cu(II) exclusively raises the question as to what role Cu(II) may play in intracellular processes. This issue is particularly important in the liver and brain. In humans, Wilson’s disease, due to mutations in ATP7B, exhibits progressive liver damage from copper accumulation; in some Bedlington terriers, mutations in COMMD1 are associated with chronic copper-overloaded liver disease, clinically distinct from Wilson’s disease. It seems unlikely that Cu(II), which generates reactive oxygen species through the Fenton reaction, has a physiological role intracellularly; however, Cu(II) might be the preferred state of copper for elimination from the cell, such as by biliary excretion. We argue that COMMD1 participates in the normal disposition of copper within the hepatocyte and we speculate about that role. COMMD1 may contribute to the mechanism of biliary excretion of copper by virtue of binding Cu(II). Additionally, or alternatively, COMMD1 may be an important component of an intracellular system for utilizing Cu(II), or for detecting and detoxifying it.

  7. The puzzle of the CNO isotope ratios in asymptotic giant branch carbon stars

    Science.gov (United States)

    Abia, C.; Hedrosa, R. P.; Domínguez, I.; Straniero, O.

    2017-02-01

    Context. The abundance ratios of the main isotopes of carbon, nitrogen and oxygen are modified by the CNO-cycle in the stellar interiors. When the different dredge-up events mix the burning material with the envelope, valuable information on the nucleosynthesis and mixing processes can be extracted by measuring these isotope ratios. Aims: Previous determinations of the oxygen isotopic ratios in asymptotic giant branch (AGB) carbon stars were at odds with the existing theoretical predictions. We aim to redetermine the oxygen ratios in these stars using new spectral analysis tools and further develop discussions on the carbon and nitrogen isotopic ratios in order to elucidate this problem. Methods: Oxygen isotopic ratios were derived from spectra in the K-band in a sample of galactic AGB carbon stars of different spectral types and near solar metallicity. Synthetic spectra calculated in local thermodynamic equillibrium (LTE) with spherical carbon-rich atmosphere models and updated molecular line lists were used. The CNO isotope ratios derived in a homogeneous way, were compared with theoretical predictions for low-mass (1.5-3 M⊙) AGB stars computed with the FUNS code assuming extra mixing both during the RGB and AGB phases. Results: For most of the stars the 16O/17O/18O ratios derived are in good agreement with theoretical predictions confirming that, for AGB stars, are established using the values reached after the first dredge-up (FDU) according to the initial stellar mass. This fact, as far as the oxygen isotopic ratios are concerned, leaves little space for the operation of any extra mixing mechanism during the AGB phase. Nevertheless, for a few stars with large 16O/17O/18O, the operation of such a mechanism might be required, although their observed 12C/13C and 14N/15N ratios would be difficult to reconcile within this scenario. Furthermore, J-type stars tend to have lower 16O/17O ratios than the normal carbon stars, as already indicated in previous studies

  8. The Infinity Puzzle - The story of the Higgs Boson:From QED to the LHC via Higgs and the Gang of Six

    CERN Document Server

    CERN. Geneva

    2013-01-01

    Rutherford and Bohr discovered the nuclear atom 100 years ago. Roughly 50 years ago a theory of this basic structure of matter was inspired by the work of Peter Higgs and others. In July 2012 the discovery "beyond reasonable doubt" of Higgs's boson, and the experimental proof of the theory, was announced and speculations about Nobel prizes mushroomed. The Economist said of Frank Close's book, The Infinity Puzzle (OUP,2012): "The Nobel Committee would be well advised to read Mr Close’s book before making their decision." This pedagogic talk reviews the ideas and the history, and assesses how the credits should be shared. The conclusions may not be what you anticipate

  9. Puzzle of the particles and the universe. The inner life of the elementary particles IX d; Raetsel der Teilchen und des Universums. Das Innenleben der Elementarteilchen IX d

    Energy Technology Data Exchange (ETDEWEB)

    Geitner, Uwe W.

    2013-04-01

    The series The Inner Life of the Elementary Particles attempts to develop the elementary particles along of a genealogical tree, which begins before the ''big bang''. The simple presentation without mathematics opens also for the interested layman a plastic understanding. Volume IX discusses the known puzzles of particle physics and cosmology and offers for many of them explanation models. Explanation approaches are among others the ''DNA'' of the elementary particles and the interpretation of the quanta and the spin.

  10. The Puzzle of Coherence

    DEFF Research Database (Denmark)

    Andersen, Anne Bendix; Frederiksen, Kirsten; Beedholm, Kirsten;

    2016-01-01

    of coherence in treatment and patient pathways. The aim of our study is to explore the role of health care providers in furthering coherence. Our ambition is to identify areas for improvement or change of collaborative practice between health care providers in municipalities, hospitals and general practice...... initiatives in health care. The present study will generate new, valuable insight into the areas of cross-sectorial health care collaboration. Our findings may facilitate change in current practice and improve the quality and coherence in patient pathways of EPCD. The findings of this study will be useful...

  11. The Birth Order Puzzle.

    Science.gov (United States)

    Zajonc, R. B.; And Others

    1979-01-01

    Discusses the controversy of the relationship between birth order and intellectual performance through a detailed evaluation of the confluence model which assumes that the rate of intellectual growth is a function of the intellectual environment within the family and associated with the special circumstances of last children. (CM)

  12. The Puzzle of Coherence

    DEFF Research Database (Denmark)

    Andersen, Anne Bendix; Frederiksen, Kirsten; Beedholm, Kirsten

    2016-01-01

    Background During the past decade, politicians and healthcare providers have strived to create a coherent healthcare system across primary and secondary healthcare sectors in Denmark. Nevertheless, elderly patients with chronic diseases (EPCD) continue to report experiences of poor-quality care...... to an acute care ward to discharge and later in meetings with healthcare providers in general practice, outpatient clinics, home care and physiotherapy. Furthermore, field observations were conducted in general practice, home care and rehabilitation settings. Research design An explorative design based...... on an interactionistic approach was used. As a consequence, the focus of data collection is the production of meaning happening between human beings in social interaction in the field of cross-sectorial collaboration. Research questions The research questions reflect the interactionistic approach as they concentrate...

  13. Puzzles on grammatical gender

    NARCIS (Netherlands)

    Roodenburg, J.; Hulk, A.

    2008-01-01

    This article explores the link between the notion of "neuter" gender and default in Dutch, a language that does not make the familiar distinction between masculine and feminine nouns, but opposes non-neuter nouns to neuter nouns. In trying to extend to Dutch the analysis of "neuter" as a default

  14. The Format Puzzle

    DEFF Research Database (Denmark)

    Knudsen, Bo Nissen

    The first volume in the printed place-name series Danmarks Stednavne (Place-names of Denmark) was published in 1922 – 12 years after the establishment of Stednavneudvalget (the Place-Name Commission) in 1910. In 2013 volume 26 is due to be published, and still only about 2/3 of the area of Denmar...

  15. Striking Oil: Another Puzzle

    NARCIS (Netherlands)

    G. Driesprong (Gerben); B. Jacobsen (Ben); B. Maat (Benjamin)

    2003-01-01

    textabstractWe find that changes in oil prices strongly predict future stock market returns in many countries in the world. In our thirty year sample of monthly data for developed stock markets, we find statistically significant predictability in 12 out of the 18 countries and in a world market inde

  16. Amino Acid Crossword Puzzle

    Science.gov (United States)

    Sims, Paul A.

    2011-01-01

    Learning the 20 standard amino acids is an essential component of an introductory course in biochemistry. Later in the course, the students study metabolism and learn about various catabolic and anabolic pathways involving amino acids. Learning new material or concepts often is easier if one can connect the new material to what one already knows;…

  17. The Tradable Shares Puzzle

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    A huge number of restricted shares were made tradable in March in the mainland stock market,testing the capability of the fragile capital market Ping An of China has been made the main scapegoat of this year s stock market plunge.A month after its refinancing plan announcement- equivalent to recreating a new Ping An- its 3.12 billion restricted shares were made tradable on March 3,accounting for almost

  18. Solving the Power Puzzle

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    China’s power supply and consumption system needs market-oriented reform Under constant pressure from power companies, the National Development and Reform Commission (NDRC) has agreed to raise electricity prices. The move comes despite the fact that price hikes could have a negative trickle down effect hindering the Central Government’s efforts to rein in inflation.

  19. The Format Puzzle

    DEFF Research Database (Denmark)

    Knudsen, Bo Nissen

    been supplemented by an official cadastral name database as well as a database of medieval settlement names. And in order to obtain some consistency, new information categories such as name generics have been added, geo-coding from the cadastral database has been applied to the names from the printed...... series when possible – and a web-tool for manual geo-coding of the remaining names has been developed....

  20. Forex Reserve Puzzle

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    China faces pressure of preserving the value of its $3 trillion foreign exchange reserves While already under pressure to revalue its currency,the yuan,against the U.S.dollar,China also faces the challenge of stifling vast losses to its foreign exchange reserve,mostly denominated in U.S.dollars.These losses to foreign exchange

  1. Puzzles on grammatical gender

    NARCIS (Netherlands)

    Roodenburg, J.; Hulk, A.

    2008-01-01

    This article explores the link between the notion of "neuter" gender and default in Dutch, a language that does not make the familiar distinction between masculine and feminine nouns, but opposes non-neuter nouns to neuter nouns. In trying to extend to Dutch the analysis of "neuter" as a default pro

  2. The Puzzle of Coherence

    DEFF Research Database (Denmark)

    Andersen, Anne Bendix; Frederiksen, Kirsten; Beedholm, Kirsten;

    2016-01-01

    in general practice, outpatient clinics, home care and physiotherapy. Furthermore, field observations are conducted in general practice, home care and rehabilitation settings. Perspectives Knowledge about the practice of cross-sectorial collaboration is crucial to the future planning of collaborating...... initiatives in health care. The present study will generate new, valuable insight into the areas of cross-sectorial health care collaboration. Our findings may facilitate change in current practice and improve the quality and coherence in patient pathways of EPCD. The findings of this study will be useful...

  3. China: moral puzzles.

    Science.gov (United States)

    Xu, T M

    1990-01-01

    This is the first of a set of three articles concerned with "bioethics on the Pacific Rim." The author, vice president of Beijing Medical University and vice chairman of the Beijing Academic Association for Morality, identifies population control, euthanasia, and the allocation of health care resources as bioethical issues of current interest in his country. Population policy in China is grounded in public welfare arguments. The idea of a right to choose one's death is found in Chinese philosophy, although Chinese legal experts believe that euthanasia is not compatible with present criminal, civil, or family law. Allocation of health resources remains a problem in China, even throughout the free medical service that serves a small portion, largely composed of government employees, of the country's population of 1.08 billion.

  4. Physician Compare

    Data.gov (United States)

    U.S. Department of Health & Human Services — Physician Compare, which meets Affordable Care Act of 2010 requirements, helps you search for and select physicians and other healthcare professionals enrolled in...

  5. Comparative Advantage

    DEFF Research Database (Denmark)

    Zhang, Jie; Jensen, Camilla

    2007-01-01

    that are typically explained from the supply-side variables, the comparative advantage of the exporting countries. A simple model is proposed and tested. The results render strong support for the relevance of supply-side factors such as natural endowments, technology, and infrastructure in explaining international...

  6. Comparative hemorheology

    OpenAIRE

    Başkurt, Oğuz K.; Meiselman, Herbert J.

    2013-01-01

    Comparative data on blood composition and blood flow properties indicate different levels of interspecies variation for several parameters. Hematocrit and hemoglobin levels have relatively low variability among mammals, while mean cell volume and red blood cell (RBC) count are more variable. There is also a difference of variability between high and low shear rate blood viscosity in mammals, with low shear rate viscosity having a higher degree of interspecies variation. This observation paral...

  7. Comparative evaluations.

    Science.gov (United States)

    Bibace, Roger

    2008-03-01

    My response to Engelmann (2008) will be based on several questions that will allow both its author and the general reader to determine whether the assumptions I make as an interpreter of this complex paper are congruent or incongruent with their own interpretations of the text. The interpretations by the writer, by any commentator, and the diverse interpretations of a general audience together with my own interpretations will, I hope, facilitate some fruitful 'comparative evaluations.' I articulate my inferences of the most dense part of the paper, namely the 'concrete immediate Consciousness and the developing absent outside.' My hope is to address Engelmann's question: "Am I in a better disposition to judge modern theories of consciousness?" The last section of my response spells out more personal comments to my all too brief and single encounter with Arno Engelmann. It is there that Arno Engelmann's fascinating statement "I am a citizen of the world" is addressed through its counterparts in my life.

  8. Putting the Whole Grain Puzzle Together: Health Benefits Associated with Whole Grains—Summary of American Society for Nutrition 2010 Satellite Symposium123

    Science.gov (United States)

    Jonnalagadda, Satya S.; Harnack, Lisa; Hai Liu, Rui; McKeown, Nicola; Seal, Chris; Liu, Simin; Fahey, George C.

    2011-01-01

    The symposium “Putting the Whole Grain Puzzle Together: Health Benefits Associated with Whole Grains” sponsored by the ASN brought together researchers to review the evidence regarding the health benefits associated with whole grains. Current scientific evidence indicates that whole grains play an important role in lowering the risk of chronic diseases, such as coronary heart disease, diabetes, and cancer, and also contribute to body weight management and gastrointestinal health. The essential macro- and micronutrients, along with the phytonutrients present in whole grains, synergistically contribute to their beneficial effects. Current evidence lends credence to the recommendations to incorporate whole grain foods into a healthy diet and lifestyle program. The symposium also highlighted the need for further research to examine the role of whole grain foods in disease prevention and management to gain a better understanding of their mechanisms of action. PMID:21451131

  9. Putting the whole grain puzzle together: health benefits associated with whole grains--summary of American Society for Nutrition 2010 Satellite Symposium.

    Science.gov (United States)

    Jonnalagadda, Satya S; Harnack, Lisa; Liu, Rui Hai; McKeown, Nicola; Seal, Chris; Liu, Simin; Fahey, George C

    2011-05-01

    The symposium "Putting the Whole Grain Puzzle Together: Health Benefits Associated with Whole Grains" sponsored by the ASN brought together researchers to review the evidence regarding the health benefits associated with whole grains. Current scientific evidence indicates that whole grains play an important role in lowering the risk of chronic diseases, such as coronary heart disease, diabetes, and cancer, and also contribute to body weight management and gastrointestinal health. The essential macro- and micronutrients, along with the phytonutrients present in whole grains, synergistically contribute to their beneficial effects. Current evidence lends credence to the recommendations to incorporate whole grain foods into a healthy diet and lifestyle program. The symposium also highlighted the need for further research to examine the role of whole grain foods in disease prevention and management to gain a better understanding of their mechanisms of action.

  10. bar{B}_{d,s} → D^{*}_{d,s} V and bar{B}_{d,s}^* → D_{d,s} V decays in QCD factorization and possible puzzles

    Science.gov (United States)

    Chang, Qin; Chen, Ling-Xin; Zhang, Yun-Yun; Sun, Jun-Feng; Yang, Yue-Ling

    2016-10-01

    Motivated by the rapid development of heavy-flavor experiments, phenomenological studies of nonleptonic bar{B}_{d,s} → D^{*}_{d,s} V and bar{B}_{d,s}^* → D_{d,s} V (V=ρ ,K^*) decays are performed within the framework of QCD factorization. Relative to the previous work, the QCD corrections to the transverse amplitudes are evaluated at next-to-leading order. The theoretical predictions of the observables are updated. For the measured bar{B}_{d,s} → D^{*}_{d,s} V decays, the tensions between theoretical results and experimental measurements, i.e. the "R_{ds}V puzzle" and "D^{*} V (or R_{V/ℓ bar{ν }_ℓ }) puzzle", are presented after detailed analyses. For the bar{B}_{d,s}^* → D_{d,s} V decays, they have relatively large branching fractions of the order ≳ O(10^{-9}) and are in the scope of Belle-II and LHCb experiments. Moreover, they also provide a way to crosscheck the possible puzzles mentioned above through the similar ratios R_{ds}^' V} and R_{V/ℓ bar{ν }_ℓ }^' }. More refined experimental measurements and theoretical efforts are required to confirm or refute such two anomalies.

  11. Know your current I(h: interaction with a shunting current explains the puzzling effects of its pharmacological or pathological modulations.

    Directory of Open Access Journals (Sweden)

    Michele Migliore

    Full Text Available The non-specific, hyperpolarization activated, I(h current is particularly involved in epilepsy and it exhibits an excitatory or inhibitory action on synaptic integration in an apparently inconsistent way. It has been suggested that most of the inconsistencies could be reconciled invoking an indirect interaction with the M-type K(+ current, another current involved in epilepsy. However, here we show that the original experiments, and the simplified model used to explain and support them, cannot explain in a conclusive way the puzzling I(h actions observed in different experimental preparations. Using a realistic model, we show instead how and why a shunting current, such as that carried by TASK-like channels, and dependent on I(h channel is able to explain virtually all experimental findings on I(h up- or down-regulation by modulators or pathological conditions. The model results suggest several experimentally testable predictions to characterize in more details this elusive and peculiar interaction, which may be of fundamental importance in the development of new treatments for all those pathological and cognitive dysfunctions caused, mediated, or affected by I(h.

  12. Coping Strategies for the Puzzles in Poverty Identification of College Students%大学生贫困认定中的困惑及应对策略

    Institute of Scientific and Technical Information of China (English)

    张青林

    2011-01-01

    做好高校学生的贫困补助工作十分重要,它体现了国家对经济困难家庭的关爱,体现一种社会公平。但是高校学生的贫困认定是一项十分模糊的工作,有许多令人困惑的东西。文章从大学生贫困认定的标准、贫困认定中的隐私保护、贫困认定中的诚信问题三个方面进行探讨,希望能为大学生贫困认定工作提供借鉴。%The poverty identification of college students is animportant job.It reflects the social justice and the care and helpof our state to the poverty families.However,the poverty identification of college students is a very obscure work.And thereare many confusing things.This paper discusses three puzzling problems in the poverty identification of collegestudents,that is,the standards of poverty recognized,the privacy protec-tion and the credibility of the poverty students.It could prov-ide a means to the poverty identification of college students.

  13. Quasi-Normal Modes: The “Electrons” of Black Holes as “Gravitational Atoms”? Implications for the Black Hole Information Puzzle

    Directory of Open Access Journals (Sweden)

    Christian Corda

    2015-01-01

    Full Text Available Some recent important results on black hole (BH quantum physics concerning the BH effective state and the natural correspondence between Hawking radiation and BH quasi-normal modes (QNMs are reviewed, clarified, and refined. Such a correspondence permits one to naturally interpret QNMs as quantum levels in a semiclassical model. This is a model of BH somewhat similar to the historical semiclassical model of the structure of a hydrogen atom introduced by Bohr in 1913. In a certain sense, QNMs represent the “electron” which jumps from a level to another one and the absolute values of the QNMs frequencies, “triggered” by emissions (Hawking radiation and absorption of particles, represent the energy “shells” of the “gravitational hydrogen atom.” Important consequences on the BH information puzzle are discussed. In fact, it is shown that the time evolution of this “Bohr-like BH model” obeys a time dependent Schrödinger equation which permits the final BH state to be a pure quantum state instead of a mixed one. Thus, information comes out in BH evaporation in agreement with the assumption by ’t Hooft that Schröedinger equations can be used universally for all dynamics in the universe. We also show that, in addition, our approach solves the entanglement problem connected with the information paradox.

  14. Investigation for the puzzling abundance pattern of the neutron-capture elements in the ultra metal-poor star: CS 30322-023

    CERN Document Server

    Cui, W Y; Ma, K; Zhang, L

    2007-01-01

    The s-enhanced and very metal-poor star CS 30322-023 shows a puzzling abundance pattern of the neutron-capture elements, i.e. several neutron-capture elements such as Ba, Pb etc. show enhancement, but other neutron-capture elements such as Sr, Eu etc. exhibit deficient with respect to iron. The study to this sample star could make people gain a better understanding of s- and r-process nucleosynthesis at low metallicity. Using a parametric model, we find that the abundance pattern of the neutron-capture elements could be best explained by a star that was polluted by an AGB star and the CS 30322-023 binary system formed in a molecular cloud which had never been polluted by r-process material. The lack of r-process material also indicates that the AGB companion cannot have undergone a type-1.5 supernova, and thus must have had an initial mass below 4.0M$_\\odot$, while the strong N overabundance and the absence of a strong C overabundance indicate that the companion's initial mass was larger than 2.0M$_\\odot$. Th...

  15. A New Life-Span Approach to Conscientiousness and Health: Combining the Pieces of the Causal Puzzle

    Science.gov (United States)

    Friedman, Howard S.; Kern, Margaret L.; Hampson, Sarah E.; Duckworth, Angela Lee

    2014-01-01

    Conscientiousness has been shown to predict healthy behaviors, healthy social relationships, and physical health and longevity. The causal links, however, are complex and not well elaborated. Many extant studies have used comparable measures for conscientiousness, and a systematic endeavor to build cross-study analyses for conscientiousness and…

  16. Spot the difference: Solving the puzzle of hidden pictures in the lizard genome for identification of regeneration factors

    Science.gov (United States)

    Chung, Jin Woong

    2016-01-01

    All living things share some common life processes, such as growth and reproduction, and have the ability to respond to their environment. However, each type of organism has its own specialized way of managing biological events. Genetic sequences determine phenotypic and physiological traits. Based on genetic information, comparative genomics has been used to delineate the differences and similarities between various genomes, and significant progress has been made in understanding regenerative biology by comparing the genomes of a variety of lower animal models of regeneration, such as planaria, zebra fish, and newts. However, the genome of lizards has been relatively ignored until recently, even though lizards have been studied as an excellent amniote model of tissue regeneration. Very recently, whole genome sequences of lizards have been uncovered, and several attempts have been made to find regeneration factors based on genetic information. In this article, recent advances in comparative analysis of the lizard genome are introduced, and their biological implications and putative applications for regenerative medicine and stem cell biology are discussed. [BMB Reports 2016; 49(5): 249-254] PMID:26949021

  17. Spot the difference: Solving the puzzle of hidden pictures in the lizard genome for identification of regeneration factors.

    Science.gov (United States)

    Chung, Jin Woong

    2016-05-01

    All living things share some common life processes, such as growth and reproduction, and have the ability to respond to their environment. However, each type of organism has its own specialized way of managing biological events. Genetic sequences determine phenotypic and physiological traits. Based on genetic information, comparative genomics has been used to delineate the differences and similarities between various genomes, and significant progress has been made in understanding regenerative biology by comparing the genomes of a variety of lower animal models of regeneration, such as planaria, zebra fish, and newts. However, the genome of lizards has been relatively ignored until recently, even though lizards have been studied as an excellent amniote model of tissue regeneration. Very recently, whole genome sequences of lizards have been uncovered, and several attempts have been made to find regeneration factors based on genetic information. In this article, recent advances in comparative analysis of the lizard genome are introduced, and their biological implications and putative applications for regenerative medicine and stem cell biology are discussed. [BMB Reports 2016; 49(5): 249-254].

  18. A pinning puzzle: two similar, non-superconducting chemical deposits in YBCO-one pins, the other does not

    Energy Technology Data Exchange (ETDEWEB)

    Sawh, Ravi-Persad; Weinstein, Roy; Gandini, Alberto; Skorpenske, Harley; Parks, Drew, E-mail: Weinstein@uh.ed [Beam Particle Dynamics Laboratories, University of Houston, Houston, TX 77204-5005 (United States); Department of Physics, University of Houston, Houston, TX 77204-5005 (United States); Texas Center for Superconductivity at UH, University of Houston, Houston, TX 77204-5002 (United States)

    2009-09-15

    The pinning effects of two kinds of U-rich deposits in YBCO (YBa{sub 2}Cu{sub 3}O{sub 7-{delta}}) are compared. One is a five-element compound, (U{sub 0.6}Pt{sub 0.4})YBa{sub 2}O{sub 6}, which is a paramagnetic double perovskite which forms as profuse stable nanosize deposits, and pins very well. The other is a four-element compound, (U{sub 0.4}Y{sub 0.6})BaO{sub 3}, which is a ferromagnetic single perovskite which forms as profuse stable nanosize deposits and pins very weakly or not at all. The pinning comparison is done with nearly equal deposit sizes and number of deposits per unit volume for the two compounds. Evidence for the pinning capability, chemical makeup, x-ray diffraction signature, and magnetic properties of the two compounds is reported.

  19. Poverty and cumulative hospitalization in infancy and early childhood in the Quebec birth cohort: a puzzling pattern of association.

    Science.gov (United States)

    Nikièma, Béatrice; Zunzunegui, Maria Victoria; Séguin, Louise; Gauvin, Lise; Potvin, Louise

    2008-07-01

    We anticipate a negative gradient between income and hospitalization, since income is positively associated with good health. In a previous cross-sectional study, we reported an unexpected pattern of association between poverty and hospitalization for 5-month-old infants in Quebec. This study re-examines the poverty-hospitalization relationship within a longitudinal population study of the same birth cohort aged 3.5 years. Life table analysis, multivariable proportional hazard regression, and multivariable logistic regression were performed on data from the first four waves of the Quebec Longitudinal Study of Child Development (QLSCD). Probabilities of hospitalization were estimated by poverty status. The hazard ratios (HR) (Cox-regression) for duration of poverty (frequency of insufficient income) and severity of poverty (combining frequency and level of income insufficiency) were estimated, controlling for predisposing, enabling, and need determinants of hospitalization. At 3.5 years, 31% of children had been hospitalized at least once. Compared with children whose families had constantly sufficient income, children with intermittent poverty exhibited higher hospitalization risks (HR = 1.30; 95%CI = 1.04-1.64) while chronically poor children exhibited comparable hospitalization hazards (HR = 0.97; 95%CI = 0.73-1.27). Hospitalization risks for children in the severest poverty group resembled that of the non-poor group (HR = 0.99; 95%CI = 0.66-1.49), while children in less severely poor families were more likely to be hospitalized (HR = 1.26; 95%CI = 0.99-1.60). Results suggest hospitalization barriers for children living in chronic and severe poverty. If these barriers exist in a universal health care system, they may originate with primary care service organization or hospital care referral procedures.

  20. Protein folding: Over half a century lasting quest. Comment on "There and back again: Two views on the protein folding puzzle" by Alexei V. Finkelstein et al.

    Science.gov (United States)

    Krokhotin, Andrey; Dokholyan, Nikolay V.

    2017-07-01

    Most proteins fold into unique three-dimensional (3D) structures that determine their biological functions, such as catalytic activity or macromolecular binding. Misfolded proteins can pose a threat through aberrant interactions with other proteins leading to a number of diseases including Alzheimer's disease, Parkinson's disease, and amyotrophic lateral sclerosis [1,2]. What does determine 3D structure of proteins? The first clue to this question came more than fifty years ago when Anfinsen demonstrated that unfolded proteins can spontaneously fold to their native 3D structures [3,4]. Anfinsen's experiments lead to the conclusion that proteins fold to unique native structure corresponding to the stable and kinetically accessible free energy minimum, and protein native structure is solely determined by its amino acid sequence. The question of how exactly proteins find their free energy minimum proved to be a difficult problem. One of the puzzles, initially pointed out by Levinthal, was an inconsistency between observed protein folding times and theoretical estimates. A self-avoiding polymer model of a globular protein of 100-residues length on a cubic lattice can sample at least 1047 states. Based on the assumption that conformational sampling occurs at the highest vibrational mode of proteins (∼picoseconds), predicted folding time by searching among all the possible conformations leads to ∼1027 years (much larger than the age of the universe) [5]. In contrast, observed protein folding time range from microseconds to minutes. Due to tremendous theoretical progress in protein folding field that has been achieved in past decades, the source of this inconsistency is currently understood that is thoroughly described in the review by Finkelstein et al. [6].

  1. Interviewing patients and practitioners working together in teams. A multi-layered puzzle: putting the pieces together.

    Science.gov (United States)

    Ringstad, Oystein

    2010-08-01

    This paper presents and evaluates a methodological approach aiming at analysing some of the complex interaction between patients and different health care practitioners working together in teams. Qualitative health care research describes the values, perceptions and conceptions of patients and practitioners. In modern clinical work patients and professional practitioners often work together on complex cases involving different kinds of knowledge and values, each of them representing different perspectives. We need studies designed to capture this complexity. The methodological approach presented here is exemplified with a study in rehabilitation medicine. In this part of the health care system the clinical work is organized in multi-professional clinical teams including patients, handling complex rehabilitation processes. In the presented approach data are collected in individual in-depth interviews to have thorough descriptions of each individual perspective. The interaction in the teams is analysed by comparing different descriptions of the same situations from the involved individuals. We may then discuss how these perceptions relate to each other and how the individuals in the team interact. Two examples from an empirical study are presented and discussed, illustrating how communication, differences in evaluations and the interpretation of incidents, arguments, emotions and interpersonal relations may be discussed. It is argued that this approach may give information which can supplement the methods commonly applied in qualitative health care research today.

  2. Dark Matter Halos as Particle Colliders: Unified Solution to Small-Scale Structure Puzzles from Dwarfs to Clusters.

    Science.gov (United States)

    Kaplinghat, Manoj; Tulin, Sean; Yu, Hai-Bo

    2016-01-29

    Astrophysical observations spanning dwarf galaxies to galaxy clusters indicate that dark matter (DM) halos are less dense in their central regions compared to expectations from collisionless DM N-body simulations. Using detailed fits to DM halos of galaxies and clusters, we show that self-interacting DM (SIDM) may provide a consistent solution to the DM deficit problem across all scales, even though individual systems exhibit a wide diversity in halo properties. Since the characteristic velocity of DM particles varies across these systems, we are able to measure the self-interaction cross section as a function of kinetic energy and thereby deduce the SIDM particle physics model parameters. Our results prefer a mildly velocity-dependent cross section, from σ/m≈2  cm^{2}/g on galaxy scales to σ/m≈0.1  cm^{2}/g on cluster scales, consistent with the upper limits from merging clusters. Our results dramatically improve the constraints on SIDM models and may allow the masses of both DM and dark mediator particles to be measured even if the dark sector is completely hidden from the standard model, which we illustrate for the dark photon model.

  3. Oxygen diffusion measurements in porous media on the ISS: One piece of the puzzle for optimal root zone performance

    Science.gov (United States)

    Jones, Scott; Heinse, Robert; Or, Dani; Topham, T. Shane; Podolsky, Igor; Bingham, Gail

    Optimization of Root Zone Substrates (ORZS) are currently being researched to expand plantbased bio-regenerative life support systems. This NASA funded research investigates the effect of reduced-gravity on porous media fluid management at the root-module and pore scale, necessitated by current limitations in root zone management that may have led to stunted, often unexplained plant vigor. Among them, alterations in substrate water retention and oxygen diffusion are restraining optimal support of plant growth. Our work explores the effect of gravity on the distribution and flow of fluids in porous media. These effects demonstrate unanticipated behavior in fluid transport with fluid distribution in pursuit of a capillary equilibrium within the hysteretic, contingent energy potential of water and continuity of phases for the supply of plant resources to the root. We investigate how accounts of fluid transport are part of a larger story of fluid distribution when gravitational and capillary forces are shifting. We now have data from the International Space Station that were collected in a novel experimental setup developed and tested for measurement of oxygen diffusion in partially saturated porous media under microgravity conditions with a sealed dual-chamber diffusion cell. The experiment flew on the International Space Station between July and September 2007 as part of the ORZS- MIS experimental flight package. In comparing oxygen diffusion measurements in microgravity with earth-based data, results point to enhanced hysteresis in oxygen diffusion dependency on air-filled porosity in microgravity. This indicates altered water distribution patterns relative to earth-based measurements. Considering air invasion during drainage, we hypothesize that a critical air-filled pathway forms at higher saturation in microgravity due to the absence of hydrostatic water distribution. A shift in the critical air-filled porosity in microgravity would require adjustment in plant

  4. Plaguicidas en la dieta: aportando piezas al rompecabezas Pesticides in the diet: adding pieces to the puzzle

    Directory of Open Access Journals (Sweden)

    Ángel Vicente

    2004-12-01

    Full Text Available Objetivos: Mejorar la información sobre la exposición a plaguicidas mediante la dieta en nuestro país con la presentación de los resultados de detección de 88 parámetros de plaguicidas en 1.109 muestras de alimentos, obtenidas entre 1998 y 2003 para el programa de Investigación de la Calidad Sanitaria de los Alimentos (ICSA de Barcelona. Material y método: Se presentan los resultados por grupos de alimentos y se comparan con la situación en el período anterior para frutas y hortalizas. La significación de las diferencias observadas se estima mediante la prueba de la χ². Resultados: En las 1.109 muestras analizadas se obtuvieron 116 resultados positivos para plaguicidas (10,5%. En el 1,5% de las muestras se detectaron halogenados persistentes y en el 14,4%, otros plaguicidas. Los positivos se concentran en frutas, hortalizas, especias y cereales y sus derivados. No hay positivos entre los aceites vegetales, los huevos ni los productos de la pesca, y casi no hay en los lácticos ni en los cárnicos. Las frutas concentran la mayor presencia de plaguicidas, en todos los casos no persistentes. Las hortalizas tienen menos plaguicidas, pero en ellas se detecta algún tipo de organoclorado. Al comparar los valores en las frutas y verduras con los de 1989-1997 no se aprecian diferencias que alcancen la significación estadística. Conclusiones: Aunque el volumen de muestras con plaguicidas es relevante, en su mayoría no son por productos halogenados persistentes. Destaca la elevada presencia de plaguicidas en la fruta.Objectives: To improve information on exposure to pesticides through diet in Spain by reporting the results on 88 pesticide parameters in 1,109 food samples obtained between 1998 and 2003 as part of the Barcelona program for research on the health quality of foods. Material and method: The results are presented by food groups. For fruits and vegetables, the results were compared with those for the previous period. Statistical

  5. anti B{sub d,s} → D{sup *}{sub d,s}V and anti B{sup *}{sub d,s} → D{sub d,s}V decays in QCD factorization and possible puzzles

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Qin [Henan Normal University, Institute of Particle and Nuclear Physics, Henan (China); Central China Normal University, Institute of Particle Physics, Wuhan (China); Chen, Ling-Xin; Zhang, Yun-Yun; Sun, Jun-Feng; Yang, Yue-Ling [Henan Normal University, Institute of Particle and Nuclear Physics, Henan (China)

    2016-10-15

    Motivated by the rapid development of heavy-flavor experiments, phenomenological studies of nonleptonic anti B{sub d,s} → D{sup *}{sub d,s}V and anti B{sup *}{sub d,s} → D{sub d,s}V (V = ρ, K*) decays are performed within the framework of QCD factorization. Relative to the previous work, the QCD corrections to the transverse amplitudes are evaluated at next-to-leading order. The theoretical predictions of the observables are updated. For the measured anti B{sub d,s} → D{sup *}{sub d,s}V decays, the tensions between theoretical results and experimental measurements, i.e. the ''R{sub ds}{sup V} puzzle'' and ''D*V (or R{sub V/l} {sub anti} {sub ν{sub l)}} puzzle'', are presented after detailed analyses. For the anti B{sup *}{sub d,s} → D{sub d,s}V decays, they have relatively large branching fractions of the order >or similar O(10{sup -9}) and are in the scope of Belle-II and LHCb experiments. Moreover, they also provide a way to crosscheck the possible puzzles mentioned above through the similar ratios R{sub ds}{sup 'V} and R{sup '}{sub V/l} {sub anti} {sub ν{sub l.}} More refined experimental measurements and theoretical efforts are required to confirm or refute such two anomalies. (orig.)

  6. Pharmacoresistant epilepsy: unmet needs in solving the puzzle(s).

    Science.gov (United States)

    Weaver, Donald F; Pohlmann-Eden, Bernd

    2013-05-01

    Pharmacoresistant epilepsy is a significant medical problem. The 2nd Halifax International Epilepsy Conference & Retreat identified crucial needs, which if successfully addressed, will aid in paving the way to improved lives for people with pharmacoresistant epilepsy. These are needs: (1) for an evidence-based and dynamic definition of pharmacoresistant epilepsy; (2) for a comprehensive description of the natural history of pharmacoresistant epilepsy; (3) for a comprehensive description of the complications and comorbidities of pharmacoresistant epilepsy; (4) for a rigorous delineation of the epidemiology and socioeconomic impact of pharmacoresistant epilepsy; (5) for clinically meaningful diagnostic and prognostic physiologically based electroencephalography (EEG) biomarkers; (6) for clinically meaningful diagnostic and prognostic anatomically based (MRI Imaging) biomarkers; (7) for biomolecular/biochemical mechanistic understanding of etiopathogenesis for pharmacoresistant epilepsy; (8) for representative animal models of pharmacoresistant epilepsy; (9) for new and effective drugs or other novel treatments for pharmacoresistant epilepsy; and (10) to promote continuing research and research funding targeting pharmacoresistant epilepsy.

  7. A Comparative Study of Teaching Comparative Education

    OpenAIRE

    2007-01-01

    The purpose of this paper is to characterize the comparative education subjects offered in different programs in different foreign universities. As a subject, comparative education has not been firmly institutionalized in education programs in Japanese universities. There was a movement which aimed at making comparative education as one of the mandatory subjects in the teacher training program, however it was not successful. To date, comparative education subject has been offered in various p...

  8. Slow proton transfer coupled to unfolding explains the puzzling results of single-molecule experiments on BBL, a paradigmatic downhill folding protein.

    Directory of Open Access Journals (Sweden)

    Michele Cerminara

    Full Text Available A battery of thermodynamic, kinetic, and structural approaches has indicated that the small α-helical protein BBL folds-unfolds via the one-state downhill scenario. Yet, single-molecule fluorescence spectroscopy offers a more conflicting view. Single-molecule experiments at pH 6 show a unique half-unfolded conformational ensemble at mid denaturation, whereas other experiments performed at higher pH show a bimodal distribution, as expected for two-state folding. Here we use thermodynamic and laser T-jump kinetic experiments combined with theoretical modeling to investigate the pH dependence of BBL stability, folding kinetics and mechanism within the pH 6-11 range. We find that BBL unfolding is tightly coupled to the protonation of one of its residues with an apparent pKa of ~ 7. Therefore, in chemical denaturation experiments around neutral pH BBL unfolds gradually, and also converts in binary fashion to the protonated species. Moreover, under the single-molecule experimental conditions (denaturant midpoint and 279 K, we observe that proton transfer is much slower than the ~ 15 microseconds folding-unfolding kinetics of BBL. The relaxation kinetics is distinctly biphasic, and the overall relaxation time (i.e. 0.2-0.5 ms becomes controlled by the proton transfer step. We then show that a simple theoretical model of protein folding coupled to proton transfer explains quantitatively all these results as well as the two sets of single-molecule experiments, including their more puzzling features. Interestingly, this analysis suggests that BBL unfolds following a one-state downhill folding mechanism at all conditions. Accordingly, the source of the bimodal distributions observed during denaturation at pH 7-8 is the splitting of the unique conformational ensemble of BBL onto two slowly inter-converting protonation species. Both, the unprotonated and protonated species unfold gradually (one-state downhill, but they exhibit different degree of unfolding

  9. 中国股票市场非参与之谜分析%Analysis of the Non-Participation Puzzle of China's Stock Market

    Institute of Scientific and Technical Information of China (English)

    黄毓慧

    2014-01-01

    用微观调研数据分析中国股票市场非参与之谜,验证国外文献对该问题的解释:资金参与成本、认知水平,并进一步探索受教育程度、信息对认知水平的影响。实证分析从参与决策、参与深度两个层次递进展开,首先采用2SPLS克服认知水平和股市参与之间的内生性,证实了股市参与和认知之间存在双向因果关系,其次采用Tobit模型研究股票市场的参与深度。研究表明:中国股票市场参与受财富、教育、认知、信息等因素的影响,现阶段认知和信息的影响程度大于财富的影响程度,是影响中国股票市场参与的主要因素。结论凸显了投资者教育的重要性和紧迫性。%The paper analyzes the non-participation puzzle of China's stock market with mi-croscopic investigation data to prove the explanation in foreign literatures about the problem,such as capital participation cost and cognition level. Further studies are made on the education back-ground,and the influence of information on cognition level. Empirical study is made from two lev-els. Firstly,2SPLS is used to overcome the endogenous relationship between cognition level and stock market participation,which proves that there is a mutual cause-effect relationship between the two factors. Secondly,Tobit model is used to study the participation width of the stock market. Research shows that China's stock market is influenced by factors such as wealth,education,cog-nition and information. At present,the impacts of cognition and information are larger than that of the wealth,which are the main factors influencing China's stock market participation. Therefore, the education of investors becomes more important and urgent.

  10. The puzzle of monogamous marriage

    Science.gov (United States)

    Henrich, Joseph; Boyd, Robert; Richerson, Peter J.

    2012-01-01

    The anthropological record indicates that approximately 85 per cent of human societies have permitted men to have more than one wife (polygynous marriage), and both empirical and evolutionary considerations suggest that large absolute differences in wealth should favour more polygynous marriages. Yet, monogamous marriage has spread across Europe, and more recently across the globe, even as absolute wealth differences have expanded. Here, we develop and explore the hypothesis that the norms and institutions that compose the modern package of monogamous marriage have been favoured by cultural evolution because of their group-beneficial effects—promoting success in inter-group competition. In suppressing intrasexual competition and reducing the size of the pool of unmarried men, normative monogamy reduces crime rates, including rape, murder, assault, robbery and fraud, as well as decreasing personal abuses. By assuaging the competition for younger brides, normative monogamy decreases (i) the spousal age gap, (ii) fertility, and (iii) gender inequality. By shifting male efforts from seeking wives to paternal investment, normative monogamy increases savings, child investment and economic productivity. By increasing the relatedness within households, normative monogamy reduces intra-household conflict, leading to lower rates of child neglect, abuse, accidental death and homicide. These predictions are tested using converging lines of evidence from across the human sciences. PMID:22271782

  11. The Nominal Share Price Puzzle

    National Research Council Canada - National Science Library

    William C. Weld; Roni Michaely; Richard H. Thaler; Shlomo Benartzi

    2009-01-01

    ... investigate in this paper is whether vestigial norms and customs affect corporate decision making. Consider the following fact: The average nominal price for a share of stock on the New York Stock exchange has remained roughly constant (about $35) since the Great Depression. The mechanism that has allowed share prices to remain remarkably con...

  12. Horse trichinellosis, an unresolved puzzle

    Directory of Open Access Journals (Sweden)

    Pozio E.

    2001-06-01

    Full Text Available In spite of routine controls to detect Trichinella larvae in horse-meat, human infections due to horse-meat consumption continue to occur in France and Italy, The epidemiology of horse trichinellosis since its discovery in 1975 is outlined, addressing the possible modes of natural transmission to horses, the need to develop more sensitive methods for detecting Trichinella larvae in horses, and the economic impact of horse trichinellosis. Investigations of human outbreaks due to horse-meat consumption have implicated single cases of inadequate veterinary controls on horses imported from non-European Union countries. In particular, most cases of human infection have been attributed to horses imported from Eastern Europe, where pig trichinellosis is re-emerging and the main source of infection in horses.

  13. Chlorophyll d: the puzzle resolved

    DEFF Research Database (Denmark)

    Larkum, Anthony W D; Kühl, Michael

    2005-01-01

    Chlorophyll a (Chl a) has always been regarded as the sole chlorophyll with a role in photochemical conversion in oxygen-evolving phototrophs, whereas chlorophyll d (Chl d), discovered in small quantities in red algae in 1943, was often regarded as an artefact of isolation. Now, as a result...... of discoveries over the past year, it has become clear that Chl d is the major chlorophyll of a free-living and widely distributed cyanobacterium that lives in light environments depleted in visible light and enhanced in infrared radiation. Moreover, Chl d not only has a light-harvesting role but might also...... replace Chl a in the special pair of chlorophylls in both reactions centers of photosynthesis. Udgivelsesdato: 2005-Aug...

  14. The puzzling MILAGRO hot spots

    CERN Document Server

    Drury, Luke

    2008-01-01

    We discuss the reported detection by the MILAGRO experiment of localised hot spots in the cosmic ray arrival distribution and the difficulty of interpreting these observations. A model based on secondary neutron production in the heliotail is shown to fail. An alternative model based on loss-cone leakage through a magnetic trap from a local source region is proposed.

  15. The Database Architecture Jigsaw Puzzle

    NARCIS (Netherlands)

    Kersten, M.L.

    2008-01-01

    Each DBMS represents a solution in a design space covering hundreds of parameters. The sheer size of this space leaves large parts unexplored, but also requires courage. The open-source MonetDB system is used to exemplify the pitfalls and opportunities of such an exploration into the realm of

  16. Scalp Mycetoma- A Diagnostic Puzzle

    Directory of Open Access Journals (Sweden)

    Maiti P K

    2000-01-01

    Full Text Available A 30 year old male with a history of avulsion injury of scalp presented with discharging sinuses one year after wound repair. Patients was admitted in Neuro-Sugery unit. Subsequently microscopic grains were detected from the sinuses and N. Asteroides was grown in culture. Patient was treated with contrimoxazole. One year follow up showed clinical recovery.

  17. America's Infant-Mortality Puzzle.

    Science.gov (United States)

    Eberstadt, Nicholas

    1991-01-01

    Conventional explanations attributing the high infant mortality rate in United States to the prevalence of poverty and lack of adequate health care do not tell the whole story. Contributions of parental behavior, lifestyles, and public health care availability versus utilization must be examined in determining public policies to address the…

  18. Geminga's puzzling pulsar wind nebula

    CERN Document Server

    Posselt, B; Slane, P O; Romani, R; Bucciantini, N; Bykov, A M; Kargaltsev, O; Weisskopf, M C; Ng, C -Y

    2016-01-01

    We report on six new Chandra observations of the Geminga pulsar wind nebula (PWN). The PWN consists of three distinct elongated structures - two $\\approx 0.2 d_{250}$ pc long lateral tails and a segmented axial tail of $\\approx 0.05 d_{250}$ pc length, where $d_{250}=d/(250 {\\rm pc})$. The photon indices of the power law spectra of the lateral tails, $\\Gamma \\approx 1$, are significantly harder than those of the pulsar ($\\Gamma \\approx 1.5$) and the axial tail ($\\Gamma \\approx 1.6$). There is no significant diffuse X-ray emission between the lateral tails -- the ratio of the X-ray surface brightness between the south tail and this sky area is at least 12. The lateral tails apparently connect directly to the pulsar and show indication of moving footpoints. The axial tail comprises time-variable emission blobs. However, there is no evidence for constant or decelerated outward motion of these blobs. Different physical models are consistent with the observed morphology and spectra of the Geminga PWN. In one scena...

  19. Phakellistatins: An Underwater Unsolved Puzzle

    Science.gov (United States)

    Meli, Alessandra; Tedesco, Consiglia; Della Sala, Giorgio; Schettini, Rosaria; Albericio, Fernando; De Riccardis, Francesco; Izzo, Irene

    2017-01-01

    A critical summary on the discovery of the nineteen members of the phakellistatin family (phakellistatin 1–19), cytotoxic proline-rich cyclopeptides of marine origin, is reported. Isolation, structural elucidation, and biological properties of the various-sized natural macrocycles are described, along with the total syntheses and the enigmatic issues of the cytotoxic activity reproducibility. PMID:28335479

  20. The puzzle of monogamous marriage.

    Science.gov (United States)

    Henrich, Joseph; Boyd, Robert; Richerson, Peter J

    2012-03-01

    The anthropological record indicates that approximately 85 per cent of human societies have permitted men to have more than one wife (polygynous marriage), and both empirical and evolutionary considerations suggest that large absolute differences in wealth should favour more polygynous marriages. Yet, monogamous marriage has spread across Europe, and more recently across the globe, even as absolute wealth differences have expanded. Here, we develop and explore the hypothesis that the norms and institutions that compose the modern package of monogamous marriage have been favoured by cultural evolution because of their group-beneficial effects-promoting success in inter-group competition. In suppressing intrasexual competition and reducing the size of the pool of unmarried men, normative monogamy reduces crime rates, including rape, murder, assault, robbery and fraud, as well as decreasing personal abuses. By assuaging the competition for younger brides, normative monogamy decreases (i) the spousal age gap, (ii) fertility, and (iii) gender inequality. By shifting male efforts from seeking wives to paternal investment, normative monogamy increases savings, child investment and economic productivity. By increasing the relatedness within households, normative monogamy reduces intra-household conflict, leading to lower rates of child neglect, abuse, accidental death and homicide. These predictions are tested using converging lines of evidence from across the human sciences.

  1. Heisenberg Honeycombs Solve Veneziano Puzzle

    CERN Document Server

    Kholodenko, A L

    2006-01-01

    In this paper we reformulate some results obtained by Heisenberg into modern mathematical language of honeycombs. This language was developed in connection with complete solution of the Horn conjecture problem. Such a reformulation is done with the purpose of posing and solving the following problem. Is by analysing the (spectroscopic) experimental data it possible to restore the underlying microscopic physical model generating these data? Development of Heisenberg's ideas happens to be the most useful for this purpose. Solution is facilitated by our earlier developed string-theoretic formalism. In this paper only qualitative arguments are presented (with few exceptions). These arguments provide enough evidence that the underelying microscopic model compatible with Veneziano-type amplitudes is the standard (i.e. non supersymmetric!) QCD. In addition, usefulness of the formalism is illustrated on numerous examples such as physically motivated solution of the saturation conjecture, derivation of the Yang-Baxter...

  2. The Exchange Rate Forecasting Puzzle

    OpenAIRE

    Francis Vitek

    2005-01-01

    We survey and update the empirical literature concerning the predictability of nominal exchange rates using structural macroeconomic models over the recent floating exchange rate period. In particular, we consider both flexible and sticky price versions of the monetary model of nominal exchange rate determination. In agreement with the existing empirical literature, we find that nominal exchange rate movements are difficult to forecast, with a random walk generally dominating the monetary mod...

  3. The Middle East population puzzle.

    Science.gov (United States)

    Omran, A R; Roudi, F

    1993-07-01

    An overview is provided of Middle Eastern countries on the following topics; population change, epidemiological transition theory and 4 patterns of transition in the middle East, transition in causes of death, infant mortality declines, war mortality, fertility, family planning, age and sex composition, ethnicity, educational status, urbanization, labor force, international labor migration, refugees, Jewish immigration, families, marriage patterns, and future growth. The Middle East is geographically defined as Bahrain, Egypt, Iraq, Jordan, Kuwait, Lebanon, Oman, Qatar, Saudi Arabia, Syria, United Arab Emirates, Yemen, Gaza and the West Bank, Iran, Turkey, and Israel. The Middle East's population grew very little until 1990 when the population was 43 million. Population was about doubled in the mid-1950s at 80 million. Rapid growth occurred after 1950 with declines in mortality due to widespread disease control and sanitation efforts. Countries are grouped in the following ways: persistent high fertility and declining mortality with low to medium socioeconomic conditions (Jordan, Oman, Syria, Yemen, and the West Bank and Gaza), declining fertility and mortality in intermediate socioeconomic development (Egypt, Lebanon, Turkey, and Iran), high fertility and declining mortality in high socioeconomic conditions (Bahrain, Iraq, Kuwait, Qatar, Saudi Arabia, and the United Arab Emirates), and low fertility and mortality in average socioeconomic conditions (Israel). As birth and death rates decline, there is an accompanying shift from communicable diseases to degenerative diseases and increases in life expectancy; this pattern is reflected in the available data from Egypt, Kuwait, and Israel. High infant and child mortality tends to remain a problem throughout the Middle East, with the exception of Israel and the Gulf States. War casualties are undetermined, yet have not impeded the fastest growing population growth rate in the world. The average fertility is 5 births/woman by the age of 45. Muslim countries tend to have larger families. Contraceptive use is low in the region, with the exception of Turkey and Egypt and among urban and educated populations. More than 40% of the population is under 15 years of age. The region is about 50% Arabic (140 million). Educational status has increased, particularly for men; the lowest literacy rates for women are in Yemen and Egypt. The largest countries are Iran, Turkey, and Egypt.

  4. The Evolutionary Puzzle of Suicide

    Directory of Open Access Journals (Sweden)

    Henri-Jean Aubin

    2013-12-01

    Full Text Available Mechanisms of self-destruction are difficult to reconcile with evolution’s first rule of thumb: survive and reproduce. However, evolutionary success ultimately depends on inclusive fitness. The altruistic suicide hypothesis posits that the presence of low reproductive potential and burdensomeness toward kin can increase the inclusive fitness payoff of self-removal. The bargaining hypothesis assumes that suicide attempts could function as an honest signal of need. The payoff may be positive if the suicidal person has a low reproductive potential. The parasite manipulation hypothesis is founded on the rodent—Toxoplasma gondii host-parasite model, in which the parasite induces a “suicidal” feline attraction that allows the parasite to complete its life cycle. Interestingly, latent infection by T. gondii has been shown to cause behavioral alterations in humans, including increased suicide attempts. Finally, we discuss how suicide risk factors can be understood as nonadaptive byproducts of evolved mechanisms that malfunction. Although most of the mechanisms proposed in this article are largely speculative, the hypotheses that we raise accept self-destructive behavior within the framework of evolutionary theory.

  5. Reviewing the Puzzle of CLIL

    Science.gov (United States)

    Ioannou Georgiou, Sophie

    2012-01-01

    Content and language integrated learning (CLIL) has become a well-known term for foreign language teachers and language researchers. A little more than a decade ago, it was a term unheard of in most staff rooms or professional conferences. This paper seeks to define CLIL and to look into the reasons that have propelled it to widespread adoption.…

  6. The Cosmic Ray Lepton Puzzle

    CERN Document Server

    Brun, Pierre; Cirelli, Marco; Moulin, Emmanuel; Glicenstein, Jean-Francois; Iocco, Fabio; Pieri, Lidia

    2010-01-01

    Recent measurements of cosmic ray electrons and positrons by PAMELA, ATIC, Fermi and HESS have revealed interesting excesses and features in the GeV-TeV range. Many possible explanations have been suggested, invoking one or more nearby primary sources such as pulsars and supernova remnants, or dark matter. Based on the output of the TANGO in PARIS --Testing Astroparticle with the New GeV/TeV Observations in Positrons And electRons : Identifying the Sources-- workshop held in Paris in May 2009, we review here the latest experimental results and we discuss some virtues and drawbacks of the many theoretical interpretations proposed so far.

  7. Pieces to the Motivation Puzzle.

    Science.gov (United States)

    Powell, Lacey

    1984-01-01

    Students enter music classes for various reasons. Teachers must study the group in order to understand the attitudes and motivations of students. Advises the teacher to emphasize the intrinsic rewards of learning and to set individual strategies of positive reinforcement and negative punishment. (CS)

  8. Reviewing the Puzzle of CLIL

    Science.gov (United States)

    Ioannou Georgiou, Sophie

    2012-01-01

    Content and language integrated learning (CLIL) has become a well-known term for foreign language teachers and language researchers. A little more than a decade ago, it was a term unheard of in most staff rooms or professional conferences. This paper seeks to define CLIL and to look into the reasons that have propelled it to widespread adoption.…

  9. Labour market risks and institutional determinants: an international comparative study of institutions and non-standard employment with a focus on East Asia

    OpenAIRE

    Lee, Sophia Seung-Yoon; Walker, Robert; Coleman, David

    2011-01-01

    Korea and Japan stand out in the group of OECD countries for their rapid increase in, and high levels of, non-standard employment. The empirical evidence leads us to a two-part puzzle: Why are there so many precarious workers in Korea and Japan? And what are the institutional determinants of such labour market risks? This thesis commences by introducing the concept of 'risk shift', and the fuzzy-set ideal type approach is employed to conduct a comparative study of 18 countries. The labour mar...

  10. Análise e avaliação do equity-premium puzzle no mercado acionário brasileiro usando função de utilidade recursiva

    Directory of Open Access Journals (Sweden)

    Carlos Patricio Samanez

    2012-08-01

    Full Text Available O Equity-Premium Puzzle (EPP tem sido muito estudado desde a publicação do trabalho de Mehra e Prescott (1985, em que o valor do prêmio de risco no mercado acionário Norte-Americano não pode ser verificado no contexto dos paradigmas de economia e finanças conhecidos. Posteriormente, Weil (1989 usou uma função de utilidade recursiva do tipo Kreps-Porteus, não melhorando os resultados, contudo, chamou a atenção para o que passou a ser conhecido como Risk-Free-Rate Puzzle (RFRP. O presente trabalho aplicou o modelo de Weil aos dados do mercado brasileiro no período 1990 – 2005, com o objetivo de fazer uma nova avaliação do EPP para o caso brasileiro usando função de utilidade recursiva. Ao contrário do caso norte-americano, os resultados encontrados foram satisfatórios, ficando constatado que nesse período o modelo que melhor se ajustou ao caso brasileiro foi aquele com utilidade recursiva e processo de dotação Markoviana.

  11. AirCompare

    Data.gov (United States)

    U.S. Environmental Protection Agency — AirCompare contains air quality information that allows a user to compare conditions in different localities over time and compare conditions in the same location...

  12. From Comparatism to Comparativity: Comparative Reasoning Reconsidered

    Directory of Open Access Journals (Sweden)

    Svend Erik Larsen

    2015-07-01

    Full Text Available Comparative literature was born with the national paradigm of literary historiography in the early nineteenth century when literary studies, together with other historical and comparative studies, were institutionalized as a particular field of research and higher education. The cognitive pattern generated by this paradigm comprises both national literary studies and comparative literature. They are both instances of comparatism, solidly anchored in a national context as its basic and indispensable point of reference rather than in the border crossing life of literary texts. In contrast, the comparative reasoning of the twenty first century, as exemplified by the emerging interest in world literature studies, attempts to cultivate the comparativity of the literary texts themselves – their potential to engage with several possible contexts of comparison beyond the standard theories and methods of comparatism and without giving an axiomatic priority to one of them. In the traditional aesthetics of imitation, European and non European, the double nature of any text as being organized around both an external centre and a domestic centre is already an integral part of the definition of literature in view, first of all, of their degree of canonicity. Today, more radically, all literary texts, irrespective of canonical position but as part of their status and function as literary texts, are assumed to possess the capacity to be part of several textual and cultural contexts beyond that of their place and time of origin. The paper traces the history of comparative reasoning, leading both to the national paradigm and the nineteenth century inspired comparatism and to the consequences for modern literary studies, opening a broader view of the comparative potentials of texts across time and space.

  13. Comparative Test Case Specification

    DEFF Research Database (Denmark)

    Kalyanova, Olena; Heiselberg, Per

    This document includes the specification on the IEA task of evaluation building energy simulation computer programs for the Double Skin Facades (DSF) constructions. There are two approaches involved into this procedure, one is the comparative approach and another is the empirical one. In the comp....... In the comparative approach the outcomes of different software tools are compared, while in the empirical approach the modelling results are compared with the results of experimental test cases. The comparative test cases include: ventilation, shading and geometry....

  14. $\\bar{B}_{d,s} \\to D^{*}_{d,s} V$ and $\\bar{B}_{d,s}^* \\to D_{d,s} V$ decays with QCD Factorization and Possible Puzzles

    CERN Document Server

    Chang, Qin; Zhang, Yun-Yun; Sun, Jun-Feng; Yang, Yue-Ling

    2016-01-01

    Motivated by the rapid development of heavy-flavor experiments, phenomenological studies of nonleptonic $\\bar{B}_{d,s} \\to D^{*}_{d,s} V$ and $\\bar{B}_{d,s}^* \\to D_{d,s} V$~($V=\\rho\\,,K^*$) decays are performed within the framework of QCD Factorization. Relative to previous works, the QCD corrections to the transverse amplitudes are evaluated at next-to-leading order. The theoretical predictions of the observables are updated. For the measured $\\bar{B}_{d,s} \\to D^{*}_{d,s} V$ decays, two tensions between theoretical results and experimental measurements, {\\it i.e.} "$R_{ds}^{V}$ puzzle" and "$D^{*} V$~(or $R_{V/\\ell\\bar{\

  15. FIAs (Foliation Intersection/Inflection Axes) Preserved in Porphyroblasts,the DNA of Deformation: A Solution to the Puzzle of Deformation and Metamorphism in the Colorado, Rocky Mountains, USA

    Institute of Scientific and Technical Information of China (English)

    SHAH Afroz Ahmad

    2009-01-01

    FIAs have been used extensively for more than a decade to unravel deformation and metamorphic puzzles. Orogenic processes developing early during the history or orogenesis challenge scientists because compositional layering in rocks always reactivates where multiple deformations have occurred, leaving little evidence of the history of foliation development preserved in the matrix. The foothills of the Rocky Mountains in Colorado, USA contain a succession of four FIA sets (trends) that would not have been distinguishable if porphyroblasts had not grown during the multiple deformation events that affected these rocks or if they had rotated as these events took place. They reveal that both the partitioning of deformation and the location of isograds changed significantly as the deformation proceeded.

  16. Reviews Equipment: BioLite Camp Stove Game: Burnout Paradise Equipment: 850 Universal interface and Capstone software Equipment: xllogger Book: Science Magic Tricks and Puzzles Equipment: Spinthariscope Equipment: DC Power Supply HY5002 Web Watch

    Science.gov (United States)

    2013-05-01

    WE RECOMMEND BioLite CampStove Robust and multifaceted stove illuminates physics concepts 850 Universal interface and Capstone software Powerful data-acquisition system offers many options for student experiments and demonstrations xllogger Obtaining results is far from an uphill struggle with this easy-to-use datalogger Science Magic Tricks and Puzzles Small but perfectly formed and inexpensive book packed with 'magic-of-science' demonstrations Spinthariscope Kit for older students to have the memorable experience of 'seeing' radioactivity WORTH A LOOK DC Power Supply HY5002 Solid and effective, but noisy and lacks portability HANDLE WITH CARE Burnout Paradise Car computer game may be quick off the mark, but goes nowhere fast when it comes to lab use WEB WATCH 'Live' tube map and free apps would be a useful addition to school physics, but maths-questions website of no more use than a textbook

  17. LA ENSEÑANZA DEL PASADO LOCAL EN EDUCACIÓN INICIAL: UNA EXPERIENCIA CON ROMPECABEZAS / THE TEACHING OF THE LOCAL PAST IN PRESCHOOL EDUCATION: AN EXPERIENCE WITH PUZZLES

    Directory of Open Access Journals (Sweden)

    Graciela Beatriz Yáñez

    2017-06-01

    Full Text Available La ausencia de material didáctico para la enseñanza del pasado local en la Educación Inicial, particularmente en el caso de la Ciudad de San Luis, es algo notorio y de una preocupación importante para quienes trabajamos en la formación de formadores del nivel y desarrollamos procesos de investigación sobre la temática de la historia y la memoria local. En esta línea de interés, presentamos algunos resultados obtenidos de una experiencia en salas del Nivel Inicial cuyo objeto fue la validación de un equipo de rompecabezas construidos a partir de imágenes del pasado y del presente de hitos arquitectónicos de la Ciudad de San Luis. Este conjunto de rompecabezas es parte de una serie de materiales didácticos diseñados y producidos a partir del conocimiento histórico construido en el proceso de investigación sobre la historia y memoria local a partir del Patrimonio Cultural Arquitectónico de la Ciudad de San Luis para ser utilizado en distintas instancias del sistema educativo y para el público en general. Los resultados nos permiten mirar los procesos generados por las/os niñas y niños para el armado y para el análisis de las imágenes, así como determinar las potencialidades didácticas de los rompecabezas para abordar el pasado local. / The absence of teaching materials for the teaching of the local past in Preschool Education, particularly in the case of the city of San Luis, is a notorious and important concern for those who work in the training of preschool teachers and develop research processes about local history and memory. In this regard, we present some results obtained from an experience in Preschool Education classrooms whose objective was the validation of a set of puzzles built from images of past and present architectural landmarks of the city of San Luis. This set of puzzles is part of a series of didactic materials designed and produced from the historical knowledge built in the research process about local

  18. Insulin/receptor binding: the last piece of the puzzle? What recent progress on the structure of the insulin/receptor complex tells us (or not) about negative cooperativity and activation.

    Science.gov (United States)

    De Meyts, Pierre

    2015-04-01

    Progress in solving the structure of insulin bound to its receptor has been slow and stepwise, but a milestone has now been reached with a refined structure of a complex of insulin with a "microreceptor" that contains the primary binding site. The insulin receptor is a dimeric allosteric enzyme that belongs to the family of receptor tyrosine kinases. The insulin binding process is complex and exhibits negative cooperativity. Biochemical evidence suggested that insulin, through two distinct binding sites, crosslinks two receptor sites located on each α subunit. The structure of the unliganded receptor ectodomain showed a symmetrical folded-over conformation with an antiparallel disposition. Further work resolved the detailed structure of receptor site 1, both without and with insulin. Recently, a missing piece in the puzzle was added: the C-terminal portion of insulin's B-chain known to be critical for binding and negative cooperativity. Here I discuss these findings and their implications.

  19. Dialysis Facility Compare

    Data.gov (United States)

    U.S. Department of Health & Human Services — Dialysis Facility Compare helps you find detailed information about Medicare-certified dialysis facilities. You can compare the services and the quality of care that...

  20. Ezra Pound's Comparative Poetics

    OpenAIRE

    2001-01-01

    In his paper, "Ezra Pound's Comparative Poetics," Naikan Tao concentrates on Pound's theories regarding comparison and examines the significance of his comparative studies to the formulation of his poetics, an aspect that has not been sufficiently investigated. On the basis of Pound's work, Tao observes that the conception of comparison Pound shaped through his comparative studies is the internal principle that governs the presentation of details and particulars, the method Pound advocated as...

  1. Towards Comparative Leadership

    DEFF Research Database (Denmark)

    Jensen, Merete Storgaard

    2015-01-01

    Globalization is the imitation and adaptation of knowledgesolutions or innovations, as they are diffused from one country to another” (Peter Jarvis 2007) Conducting comparative, educational research of school leadership that effects student achievement in an international perspective...... is of scientific value in qualifying the international and national knowledgebase on effective school leadership. In a methodological perspective comparative analysis in an international setting creates specifically a scientific demand of comparability and a theory based leadership - framework to guide...

  2. Comparative Test Case Specification

    DEFF Research Database (Denmark)

    Kalyanova, Olena; Heiselberg, Per

     This document includes a definition of the comparative test cases DSF200_3 and DSF200_4, which previously described in the comparative test case specification for the test cases DSF100_3 and DSF200_3 [Ref.1]....... This document includes a definition of the comparative test cases DSF200_3 and DSF200_4, which previously described in the comparative test case specification for the test cases DSF100_3 and DSF200_3 [Ref.1]....

  3. Contesting Citizenship: Comparative Analyses

    DEFF Research Database (Denmark)

    Siim, Birte; Squires, Judith

    2007-01-01

    . Comparative citizenship analyses need to be considered in relation to multipleinequalities and their intersections and to multiple governance and trans-national organisinf. This, in turn, suggests that comparative citizenship analysis needs to consider new spaces in which struggles for equal citizenship occur...

  4. Comparative Analysis of Chinese and American Cultural Values

    Institute of Scientific and Technical Information of China (English)

    LI Yu-ting

    2011-01-01

    Being aware of the differences that exist between cultures and knowing how to act when we are faced with puzzling cross-cultural situations are important skills for harmonious intercultural relations.Cross-cultural research shows that we can examine all c

  5. Nursing Home Compare Data

    Data.gov (United States)

    U.S. Department of Health & Human Services — These are the official datasets used on the Medicare.gov Nursing Home Compare Website provided by the Centers for Medicare and Medicaid Services. These data allow...

  6. Nursing Home Compare

    Data.gov (United States)

    U.S. Department of Health & Human Services — The data that is used by the Nursing Home Compare tool can be downloaded for public use. This functionality is primarily used by health policy researchers and the...

  7. Comparative State Politics.

    Science.gov (United States)

    Brooks, Gary H.

    1981-01-01

    Describes a college course dealing with comparative state politics. Students learn about the way in which political scientists employ the study of American state politics as a "laboratory" for the development of scientific explanations of political phenomena. (RM)

  8. Home Health Compare Data

    Data.gov (United States)

    U.S. Department of Health & Human Services — These are the official datasets used on the Medicare.gov Home Health Compare Website provided by the Centers for Medicare and Medicaid Services. These data allow...

  9. Dialysis Facility Compare Data

    Data.gov (United States)

    U.S. Department of Health & Human Services — These are the official datasets used on the Medicare.gov Dialysis Facility Compare Website provided by the Centers for Medicare and Medicaid Services. These data...

  10. Comparative Packaging Study

    Science.gov (United States)

    Perchonok, Michele; Antonini, David

    2008-01-01

    This viewgraph presentation describes a comparative packaging study for use on long duration space missions. The topics include: 1) Purpose; 2) Deliverables; 3) Food Sample Selection; 4) Experimental Design Matrix; 5) Permeation Rate Comparison; and 6) Packaging Material Information.

  11. Home Health Compare

    Data.gov (United States)

    U.S. Department of Health & Human Services — Home Health Compare has information about the quality of care provided by Medicare-certified home health agencies throughout the nation. Medicare-certified means the...

  12. Hospital Compare - Archived Data

    Data.gov (United States)

    U.S. Department of Health & Human Services — Hospital Compare is a consumer-oriented website that provides information on how well hospitals provide recommended care to their patients. This information can help...

  13. Hospital Compare Data

    Data.gov (United States)

    U.S. Department of Health & Human Services — These are the official datasets used on the Medicare.gov Hospital Compare Website provided by the Centers for Medicare and Medicaid Services. These data allow you to...

  14. Physician Compare Data

    Data.gov (United States)

    U.S. Department of Health & Human Services — This is the official dataset associated with the Medicare.gov Physician Compare Website provided by the Centers for Medicare and Medicaid Services (CMS). These data...

  15. Comparing Political Communication

    OpenAIRE

    Pfetsch, Barbara; Esser, Frank

    2012-01-01

    This chapter describes the maturation of comparative political communications as a sub-discipline and defines its conceptual core. It then lays out the concept of “political communication system”. At the macro-level, this model captures the patterns of interaction between media and politics as social systems; at the micro-level it captures the interactions between media and political actors as individuals or organizations. Comparative research in this tradition focuses on the structure of pol...

  16. Virtual Optical Comparator

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, Greg

    2008-10-20

    The Virtual Optical Comparator, VOC, was conceived as a result of the limitations of conventional optical comparators and vision systems. Piece part designs for mechanisms have started to include precision features on the face of parts that must be viewed using a reflected image rather than a profile shadow. The VOC concept uses a computer generated overlay and a digital camera to measure features on a video screen. The advantage of this system is superior edge detection compared to traditional systems. No vinyl charts are procured or inspected. The part size and expensive fixtures are no longer a concern because of the range of the X-Y table of the Virtual Optical Comparator. Product redesigns require only changes to the CAD image overlays; new vinyl charts are not required. The inspection process is more ergonomic by allowing the operator to view the part sitting at a desk rather than standing over a 30 inch screen. The procurement cost for the VOC will be less than a traditional comparator with a much smaller footprint with less maintenance and energy requirements.

  17. Task decomposition: a framework for comparing diverse training models in human brain plasticity studies

    Directory of Open Access Journals (Sweden)

    Emily B. J. Coffey

    2013-10-01

    Full Text Available Training studies, in which the structural or functional neurophysiology is compared before and after expertise is acquired, are increasingly being used as models for understanding the human brain’s potential for reorganization. It is proving difficult to use these results to answer basic and important questions like how task training leads to both specific and general changes in behaviour and how these changes correspond with modifications in the brain. The main culprit is the diversity of paradigms used as complex task models. An assortment of activities ranging from juggling to deciphering Morse code has been reported. Even when working in the same general domain, few researchers use similar training models. New ways to meaningfully compare complex tasks are needed. We propose a method for characterizing and deconstructing the task requirements of complex training paradigms, which is suitable for application to both structural and functional neuroimaging studies. We believe this approach will aid brain plasticity research by making it easier to compare training paradigms, identify ‘missing puzzle pieces’, and encourage researchers to design training protocols to bridge these gaps.

  18. Comparative oncology today.

    Science.gov (United States)

    Paoloni, Melissa C; Khanna, Chand

    2007-11-01

    The value of comparative oncology has been increasingly recognized in the field of cancer research, including the identification of cancer-associated genes; the study of environmental risk factors, tumor biology, and progression; and, perhaps most importantly, the evaluation of novel cancer therapeutics. The fruits of this effort are expected to be the creation of better and more specific drugs to benefit veterinary and human patients who have cancer. The state of the comparative oncology field is outlined in this article, with an emphasis on cancer in dogs.

  19. Comparative Nivkh Dictionary

    DEFF Research Database (Denmark)

    Fortescue, Michael David

    This dictionary undertakes to reconstruct the lexis and morphology of the Nivkh proto-language by marshaling and organizing all the data available in published form on the contemporary dialects. It builds upon a considerable body of descriptive and comparative work carried out by scholars who have...... World is a subject of continuing interest to both linguists and anthropologists. The dictionary does not address this question directly. Reconstructing the proto-language is an essential step, however, to any further comparative work – in particular to sorting out the relationship between Nivkh...

  20. Ebolavirus comparative genomics

    DEFF Research Database (Denmark)

    Jun, Se-Ran; Leuze, Michael R.; Nookaew, Intawat

    2015-01-01

    The 2014 Ebola outbreak in West Africa is the largest documented for this virus. To examine the dynamics of this genome, we compare more than 100 currently available ebolavirus genomes to each other and to other viral genomes. Based on oligomer frequency analysis, the family Filoviridae forms...

  1. Comparative genomics of Eukaryotes

    NARCIS (Netherlands)

    Noort, Vera van

    2007-01-01

    This thesis focuses on developing comparative genomics methods in eukaryotes, with an emphasis on applications for gene function prediction and regulatory element detection. In the past, methods have been developed to predict functional associations between gene pairs in prokaryotes. The challenge

  2. Dermatologia comparativa Comparative Dermatology

    Directory of Open Access Journals (Sweden)

    Hiram Larangeira de Almeida Jr

    2005-06-01

    Full Text Available Demonstra-se o quadro exuberante dos angiofibromas faciais em paciente do sexo masculino, de 32 anos, com esclerose tuberosa, os quais podem ser comparados com amoras.The impressive facial angiofibromas, from a 32 year-old male paciente, with the classical features of tuberous sclerosis, were compared with mulberries.

  3. Comparing Information Access Approaches.

    Science.gov (United States)

    Chalmers, Matthew

    1999-01-01

    Presents a broad view of information access, drawing from philosophy and semiology in constructing a framework for comparative discussion that is used to examine the information representations that underlie four approaches to information access--information retrieval, workflow, collaborative filtering, and the path model. Contains 32 references.…

  4. Comparative and Translatorly

    Directory of Open Access Journals (Sweden)

    Anna Rosen Guercio

    2011-12-01

    Full Text Available World literature’s natural home is comparative literature, a discipline born from and shaped by, as Vilashini Cooppan elegantly puts it, “scholarly engagements with the categories of migration, exile, diaspora, and globalization” (15. However, world literature has frequently been framed as a problem for the discipline, in large part because of its dependence on the ever-vexing and still mistrusted specter of translation. In light of the long-standing anxiety toward both world literature and translation, I propose here that comparatists do ourselves a terrible disservice if we do not urgently take up the questions raised by this disciplinary tension. Translation – in all of its attendant struggles with ethics, aesthetics, appropriation, authority – is not the problem, but, rather, should be understood as a key critical lens for comparative and world literature.In order to establish academia’s frustration with this subject, one need look no further than the “Three Reports to the America Comparative Literature Association on ‘Professional Standards’” (dating from 1965, 1975, and 1993, which return repeatedly to the problem of reading translated literature, circling around it with intense ambivalence. The moral of their story seems to be that translated texts are integral to comparative literature at the same time that they threaten its existence by undermining disciplinary exclusivity in foreign language expertise and by shining a sort of spotlight on all that literature which comparative literature may sometimes “condone” (as one of the reports puts it but to which it does not often actively attend. Even Goethe had Western European languages and literatures firmly in mind when he coined the term, “Weltliteratur.” Translations can’t help but point up the limits of the “four [likely European] languages” proposed as minimal standards for graduate students by the Green and Bernheimer reports, and on the strength of

  5. Protein Models Comparator

    CERN Document Server

    Widera, Paweł

    2011-01-01

    The process of comparison of computer generated protein structural models is an important element of protein structure prediction. It has many uses including model quality evaluation, selection of the final models from a large set of candidates or optimisation of parameters of energy functions used in template free modelling and refinement. Although many protein comparison methods are available online on numerous web servers, their ability to handle a large scale model comparison is often very limited. Most of the servers offer only a single pairwise structural comparison, and they usually do not provide a model-specific comparison with a fixed alignment between the models. To bridge the gap between the protein and model structure comparison we have developed the Protein Models Comparator (pm-cmp). To be able to deliver the scalability on demand and handle large comparison experiments the pm-cmp was implemented "in the cloud". Protein Models Comparator is a scalable web application for a fast distributed comp...

  6. The Beetle comparator implementation

    CERN Document Server

    Van Beuzekom, M G

    2003-01-01

    Measurements of the comparator thresholds on a Beetle 1.1 chip show large variations. The width of the threshold distribution is several tenths of a MIP signal for a 300 µm silicon detector, which is more than can be corrected for by individual threshold settings. Monte Carlo simulations of the production-process parameters have been performed to track the cause of this large offset spread. The main cause of the offset variation is the spread in the threshold voltage of the MOSFETs. Since this cannot easily be solved by a change in the design of the comparator as such, the solution is to increase the range of the individual threshold settings while maintaining the same resolution. This implies an increase in the number of bits for the individual thresholds. The note describes measurements and simulations for the Beetle versions 1.1 and 1.2, and the changes in the design for the Beetle 1.3.

  7. Comparing Point Clouds

    Science.gov (United States)

    2004-04-01

    Point clouds are one of the most primitive and fundamental surface representations. A popular source of point clouds are three dimensional shape...acquisition devices such as laser range scanners. Another important field where point clouds are found is in the representation of high-dimensional...framework for comparing manifolds given by point clouds is presented in this paper. The underlying theory is based on Gromov-Hausdorff distances, leading

  8. Fast Holographic Comparator

    Science.gov (United States)

    Vahey, D. W.

    1982-01-01

    Comparator is integrated-optical system constructed on a LiNb03sub. waveguide chip. Only the laser, lens and detector are external to chip. Aluminized surface gratings serve as input coupler and beam splitter. Light beams striking edges are returned by ordinary total internal reflection. Three operating modes are possible: A "screening" mode, an "identification" mode and a novel "self-subtraction" mode.

  9. Comparing apples and pears?

    DEFF Research Database (Denmark)

    Waite, Sue; Bølling, Mads; Bentsen, Peter

    2016-01-01

    Using a conceptual model focused on purposes, aims, content, pedagogy, outcomes, and barriers, we review and interpret literature on two forms of outdoor learning: Forest Schools in England and udeskole in Denmark. We examine pedagogical principles within a comparative analytical framework...... and consider how adopted pedagogies reflect and refract the culture in which they are embedded. Despite different national educational and cultural contexts, English Forest Schools and Danish udeskole share several commonalities within a naturalistic/progressive pedagogical tradition; differences appear...

  10. Comparative pharmacognosy of Pashanbhed

    Directory of Open Access Journals (Sweden)

    Poonam Verma

    2014-01-01

    Full Text Available Background: Pashanbhed is a commercially available diuretic and lithotropic drug, used to treat renal problems. It is a controversial name as it is assigned to various plants such as Bergenia ligulata, Kalanchoe pinnata, Coleus aromaticus and Rotula aquatica. Objective: To perform the comparative preliminary phytochemical screening, diuretic activity, and thin layer chromatography (TLC finger printing profile of three plants (B. ligulata, C. aromaticus, and K. pinnata, most commonly used as Pashanbhed. Materials and Methods: Diuretic potential of methanolic extract (ME of three plants were evaluated at two dose levels (500 and 1,000 mg/kg p.o., using normal Wistar rats (Lipschitz method. Furosemide (20 mg/kg p.o. was used as a standard drug. The effect on urine output and electrolyte changes were measured for 24 h and compared. All MEs were screened preliminarily for their constituents and their TLC finger printing profiles were prepared. One-way analysis of variance (ANOVA followed by Bonferroni′s multiple comparison test. P < 0.05 was considered statistically significant. Results: The MEs of all three plants have shown diuresis in normal rats. However, in intercomparison of the ME C. aromaticus (1,000 mg/kg p.o. produced more significant diuresis (P < 0.05 and electrolyte excretion compared to other test groups, the effect was at par with furosemide. The ME of these plants showed presence of alkaloids, glycosides, steroids, terpenoids, saponins, flavonoids, etc. Conclusion: The ME of C. aromaticus (1,000 mg/kg p.o. has showed highest diuretic action (4.2 among the tested extracts. This suggests the use of C. aromaticus leaves as "Pashanbhed"; the most effective diuretic drug.

  11. Comparing East and West

    DEFF Research Database (Denmark)

    Razeto, Anna

    2014-01-01

    This chapter explores the archaeological and literary evidence for marketplaces and urban forms connected to the manufacturing of bricks and metalworking in the capital cities of the contemporary empires of Rome and Han China (ca. 200 BC-200 AD). The comparative analysis of the physical aspects...... of these urban structures and the following discussion of the impact of the political, practical, ideological and economic circumstances of the two empires on the distribution and features of the architecture and industries presented, will highlight the extent to which the urban architecture of the capitals...

  12. Comparing pedigree graphs.

    Science.gov (United States)

    Kirkpatrick, Bonnie; Reshef, Yakir; Finucane, Hilary; Jiang, Haitao; Zhu, Binhai; Karp, Richard M

    2012-09-01

    Pedigree graphs, or family trees, are typically constructed by an expensive process of examining genealogical records to determine which pairs of individuals are parent and child. New methods to automate this process take as input genetic data from a set of extant individuals and reconstruct ancestral individuals. There is a great need to evaluate the quality of these methods by comparing the estimated pedigree to the true pedigree. In this article, we consider two main pedigree comparison problems. The first is the pedigree isomorphism problem, for which we present a linear-time algorithm for leaf-labeled pedigrees. The second is the pedigree edit distance problem, for which we present (1) several algorithms that are fast and exact in various special cases, and (2) a general, randomized heuristic algorithm. In the negative direction, we first prove that the pedigree isomorphism problem is as hard as the general graph isomorphism problem, and that the sub-pedigree isomorphism problem is NP-hard. We then show that the pedigree edit distance problem is APX-hard in general and NP-hard on leaf-labeled pedigrees. We use simulated pedigrees to compare our edit-distance algorithms to each other as well as to a branch-and-bound algorithm that always finds an optimal solution.

  13. Insight into the Female Longevity Puzzle: Using Register Data to Analyse Mortality and Cause of Death Behaviour Across Socio-economic Groups

    DEFF Research Database (Denmark)

    Kallestrup-Lamb, Malene; Rosenskjold, Carsten Paysen T.

    been driving the standstill for Danish women and within each socio-economic group we further analyse the cause of death pattern. Further, we compare the forecast performance of the Lee-Carter model with the multi-population Li and Lee model. The decline in life expectancy for Danish women is present...... for all subgroups, however with particular large decreases for the low-middle and middle affluence groups. We find that causes of deaths related to smoking partly contribute to the slowdown in female longevity. However the lack of improvements in deaths relating to ischemic heart diseases is dominant...

  14. Comparing dependent robust correlations.

    Science.gov (United States)

    Wilcox, Rand R

    2016-11-01

    Let r1 and r2 be two dependent estimates of Pearson's correlation. There is a substantial literature on testing H0  : ρ1  = ρ2 , the hypothesis that the population correlation coefficients are equal. However, it is well known that Pearson's correlation is not robust. Even a single outlier can have a substantial impact on Pearson's correlation, resulting in a misleading understanding about the strength of the association among the bulk of the points. A way of mitigating this concern is to use a correlation coefficient that guards against outliers, many of which have been proposed. But apparently there are no results on how to compare dependent robust correlation coefficients when there is heteroscedasicity. Extant results suggest that a basic percentile bootstrap will perform reasonably well. This paper reports simulation results indicating the extent to which this is true when using Spearman's rho, a Winsorized correlation or a skipped correlation.

  15. Comparing Measures of Sparsity

    CERN Document Server

    Hurley, Niall P

    2008-01-01

    Sparsity of representations of signals has been shown to be a key concept of fundamental importance in fields such as blind source separation, compression, sampling and signal analysis. The aim of this paper is to compare several commonlyused sparsity measures based on intuitive attributes. Intuitively, a sparse representation is one in which a small number of coefficients contain a large proportion of the energy. In this paper six properties are discussed: (Robin Hood, Scaling, Rising Tide, Cloning, Bill Gates and Babies), each of which a sparsity measure should have. The main contributions of this paper are the proofs and the associated summary table which classify commonly-used sparsity measures based on whether or not they satisfy these six propositions and the corresponding proofs. Only one of these measures satisfies all six: The Gini Index. measures based on whether or not they satisfy these six propositions and the corresponding proofs. Only one of these measures satisfies all six: The Gini Index.

  16. Comparing gains and losses.

    Science.gov (United States)

    McGraw, A Peter; Larsen, Jeff T; Kahneman, Daniel; Schkade, David

    2010-10-01

    Loss aversion in choice is commonly assumed to arise from the anticipation that losses have a greater effect on feelings than gains, but evidence for this assumption in research on judged feelings is mixed. We argue that loss aversion is present in judged feelings when people compare gains and losses and assess them on a common scale. But many situations in which people judge and express their feelings lack these features. When judging their feelings about an outcome, people naturally consider a context of similar outcomes for comparison (e.g., they consider losses against other losses). This process permits gains and losses to be normed separately and produces psychological scale units that may not be the same in size or meaning for gains and losses. Our experiments show loss aversion in judged feelings for tasks that encourage gain-loss comparisons, but not tasks that discourage them, particularly those using bipolar scales.

  17. Regeneration and reprogramming compared

    Directory of Open Access Journals (Sweden)

    Robles Vanesa

    2010-01-01

    Full Text Available Abstract Background Dedifferentiation occurs naturally in mature cell types during epimorphic regeneration in fish and some amphibians. Dedifferentiation also occurs in the induction of pluripotent stem cells when a set of transcription factors (Oct4, Sox2, Klf4 and c-Myc is over expressed in mature cell types. Results We hypothesised that there are parallels between dedifferentiation or reprogramming of somatic cells to induced pluripotent stem cells and the natural process of dedifferentiation during epimorphic regeneration. We analysed expression levels of the most commonly used pluripotency associated factors in regenerating and non-regenerating tissue and compared them with levels in a pluripotent reference cell. We found that some of the pluripotency associated factors (oct4/pou5f1, sox2, c-myc, klf4, tert, sall4, zic3, dppa2/4 and fut1, a homologue of ssea1 were expressed before and during regeneration and that at least two of these factors (oct4, sox2 were also required for normal fin regeneration in the zebrafish. However these factors were not upregulated during regeneration as would be expected if blastema cells acquired pluripotency. Conclusions By comparing cells from the regeneration blastema with embryonic pluripotent reference cells we found that induced pluripotent stem and blastema cells do not share pluripotency. However, during blastema formation some of the key reprogramming factors are both expressed and are also required for regeneration to take place. We therefore propose a link between partially reprogrammed induced pluripotent stem cells and the half way state of blastema cells and suggest that a common mechanism might be regulating these two processes.

  18. Stock Market Volatility Puzzle ,and Market Sentiment in Chinese A-share Stock Markets%我国A股市场中的波动性之谜与市场情绪

    Institute of Scientific and Technical Information of China (English)

    周洪荣; 吴卫星; 周业安

    2012-01-01

    本文使用Campbell和Shiller(1988)基于对数线性RVF的VAR非线性Wald检验方法对我国A股1994—2009期间的数据进行实证研究,结果表明样本期间我国A股股价相对其基础价值表现出“过度波动”的迹象,无论是常数超额收益率模型还是V-CAPM模型都无法对此进行解释。通过进一步定义市场情绪指数来分析这种“波动性之谜”现象的原因,结果发现市场情绪和股市“过度波动”之间存在相互作用机制,市场情绪能够对股价波动提供额外的解释。%In this paper, we analyze whether the Chinese A share stock markets exhibit excess volatility by employing the VAR methodology based on log-linear RVF of Campbell&Shiller (1988). According to our result, relative to the intrinsic value implied by dividends, Chinese A share stock markets always exhibit excessive volatility for the period of 1994 to 2009. It is difficult to explain the stock market volatility puzzle of China's stock market, no matter we run constant excess return model or V-CAPM model. We try to explain the reasons by studying the stock market sentiment index, and find evidence of an interaction mechanism between investor sentiment and excess volatility. And one more meaningful result is that adding the stock market sentiment index to our model can provide extra explanatory power for the excess volatility of the stock market.

  19. Operations dashboard: comparative study

    Science.gov (United States)

    Ramly, Noor Nashriq; Ismail, Ahmad Zuhairi; Aziz, Mohd Haris; Ahmad, Nurul Haszeli

    2011-10-01

    In this present days and age, there are increasing needs for companies to monitor application and infrastructure health. Apart from having proactive measures to secure their application and infrastructure, many see monitoring dashboards as crucial investment in disaster preparedness. As companies struggle to find the best solution to cater for their needs and interest for monitoring their application and infrastructure's health, this paper summarizes the studies made on several known off-the-shelf operations dashboard and in-house developed dashboard. A few criteria of good dashboard are collected from previous studies carried out by several researchers and rank them according to importance and business needs. The finalized criteria that will be discussed in later sections are data visualization, performance indicator, dashboard personalization, audit capability and alert/ notification. Comparative studies between several popular dashboards were then carried out to determine whether they met these criteria that we derived from the first exercise. The findings hopefully can be used to educate and provide an overview of selecting the best IT application and infrastructure operations dashboard that suit business needs, thus become the main contribution of this paper.

  20. Comparative literature in Mexico

    Directory of Open Access Journals (Sweden)

    Luz Aurora Pimentel

    2007-07-01

    Full Text Available A partir de quelques appréciations critiques, cet article propose un bref parcours de la littérature comparée au Mexique, allant des origines de la discipline à l’état actuel des études comparatistes. Il se concentre en particulier sur la façon dont la spécialité comparatiste a été intégrée aux études de troisième cycle de la Faculté de Philosophie et Lettres de l’UNAM, ainsi que sur la façon dont la discipline poursuit son évolution grâce à tout un groupe de collaborateurs.A partir de algunas apreciaciones criticas, este articulo propone un breve recorrido de la literatura comparada en México, que va de los origenes de la disciplina al estado actual de los estudios comparatistas. En él se detalla especialmente la manera en que la especialidad comparatista se integró en los estudios de postgrado de la Facultad de Filosofía y Letras de la UNAM, y cómo la disciplina prosigue su evolución gracias a todo un grupo de colaboradores.