995 resultados para P(P)OVER-BAR COLLISIONS


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We present the first measurement of photoproduction of J/psi and of two-photon production of high-mass e(+)e(-) pairs in electromagnetic (or ultra-peripheral) nucleus-nucleus interactions, using Au + Au data at root s(NN) = 200 GeV. The events are tagged with forward neutrons emitted following Coulomb excitation of one or both Au* nuclei. The event sample consists of 28 events with m(e+e-) > 2 GeV/c(2) with zero like-sign background. The measured cross sections at midrapidity of d sigma/dy (J/psi + Xn, y = 0) = 76 +/- 33 (stat) +/- 11 (syst) pb and d(2)sigma /dm dy (e(+) e(-) + Xn, y = 0) = 86 +/- 23(stat) +/- 16(syst) mu b/ (GeV/c(2)) for m(e+e-) epsilon vertical bar 2.0, 2.8 vertical bar GeV/c(2) have been compared and found to be consistent with models for photoproduction of J/psi and QED based calculations of two-photon production of e(+)e(-) pairs. (C) 2009 Elsevier B.V. All rights reserved.

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We present measurements of the charge balance function, from the charged particles, for diverse pseudorapidity and transverse momentum ranges in Au + Au collisions at root S(NN) = 200 GeV using the STAR detector at RHIC. We observe that the balance function is boost-invariant within the pseudorapidity coverage vertical bar-1.3, 1.3 vertical bar. The balance function properly scaled by the width of the observed pseudorapidity window does not depend on the position or size of the pseudorapidity window. This scaling property also holds for particles in different transverse momentum ranges. In addition, we find that the width of the balance function decreases monotonically with increasing transverse momentum for all centrality classes. (c) 2010 Elsevier B.V. All rights reserved.

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Combined fluid inclusion (FI) microthermometry, Raman spectroscopy, X-ray diffraction, C-O-H isotopes and oxygen fugacities of granulites from central Ribeira Fold Belt, SE Brazil, provided the following results: i) Magnetite-Hematite fO(2) estimates range from 10(-11.5) bar (QFM + 1) to 10(-18.3) bar (QFM - 1) for the temperature range of 896 degrees C-656 degrees C, implying fO(2) decrease from metamorphic peak temperatures to retrograde conditions; ii) 5 main types of fluid inclusions were observed: a) CO(2) and CO(2)-N(2) (0-11 mol%) high to medium density (1.01-0.59 g/cm(3)) FI; b) CO(2) and CO(2)-N(2) (0-36 mol%) low density (0.19-0.29 g/cm(3)) FI; c) CO(2) (94-95 mol%)-N(2) (3 mol%)-CH(4) (2-3 mol%)-H(2)O (water phi(v) (25 degrees C) = 0.1) FI; d) low-salinity H(2)O-CO(2) FI; and e) late low-salinity H(2)O FI; iii) Raman analyses evidence two graphite types in khondalites: an early highly ordered graphite (T similar to 450 degrees C) overgrown by a disordered kind (T similar to 330 degrees C); iv) delta(18)O quartz results of 10.3-10.7 parts per thousand, imply high-temperature CO(2) delta(18)O values of 14.4-14.8 parts per thousand, suggesting the involvement of a metamorphic fluid, whereas lower temperature biotite delta(18)O and delta D results of 7.5-8.5 parts per thousand and -54 to -67 parts per thousand respectively imply H(2)O delta(18)O values of 10-11 parts per thousand and delta D(H2O) of -23 to -36 parts per thousand suggesting delta(18)O depletion and increasing fluid/rock ratio from metamorphic peak to retrograde conditions. Isotopic results are compatible with low-temperature H(2)O influx and fO(2) decrease that promoted graphite deposition in retrograde granulites, simultaneous with low density CO(2), CO(2)-N(2) and CO(2)-N(2)-CH(4)-H(2)O fluid inclusions at T = 450-330 degrees C. Graphite delta(13)C results of -10.9 to -11.4 parts per thousand imply CO(2) delta(13)C values of -0.8 to -1.3 parts per thousand suggesting decarbonation of Cambrian marine carbonates with small admixture of lighter biogenic or mantle derived fluids. Based on these results, it is suggested that metamorphic fluids from the central segment of Ribeira Fold Belt evolved to CO(2)-N(2) fluids during granulitic metamorphism at high fO(2), followed by rapid pressure drop at T similar to 400-450 degrees C during late exhumation that caused fO(2) reduction induced by temperature decrease and water influx, turning carbonic fluids into CO(2)-H(2)O (depleting biotite delta(18)O and delta D values), and progressively into H(2)O. When fO(2) decreased substantially by mixture of carbonic and aqueous fluids, graphite deposited forming khondalites. (C) 2010 Elsevier Ltd. All rights reserved.

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Let A be a finitely generated abelian group. We describe the automorphism group Aut(A) using the rank of A and its torsion part p-part A(p). For a finite abelian p-group A of type (k(1),..., k(n)), simple necessary and sufficient conditions for an n x n-matrix over integers to be associated with an automorphism of A are presented. Then, the automorphism group Aut(A) for a finite p-group A of type (k(1), k(2)) is analyzed. (C) 2008 Mathematical Institute Slovak Academy of Sciences.

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In this article we prove that, if (U, ) is a finite dimensional baric algebra of (gamma, delta) type over a field F of characteristic not equal 2,3,5 such that gamma(2) - delta(2) + delta = 1 and 0,1, then rad(U) = R(U)boolean AND(bar(U))(2), where R(U) is the nilradical (maximal nil ideal) of U.

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The analysis of the IR carbonyl band of the alpha-methylsulfonyl-alpha-diethoxyphosphoryl p-substituted acetophenones p-Y-Ph-C(O)CH(SO(2)Me)[P(O)(OEt)(2)] (Y = OMe 1, H 2, F 3, Cl 4, Br 5 and NO(2) 6) supported by HF/6-31G(d,p) ab initio calculations of the alpha-methylsulfonyl-alpha-diethoxyphosphoryl acetophenone 2, indicated the existence of a single stable cl conformer in gas phase and in solvents of increasing polarity, along with the presence of second less stable conformation in gas phase. The cl conformer present the (SO(2)Me) group and the [P(O)(OEt(2))] groups in a syn-clinal (gauche) geometry and is stabilised through of the 0(`60)... P(%), 01NO(owl Crco), ONO)... C(,C*.), 060)... S(`S`02.,) and 0(`S-02) q o) electronic interactions 08along with H(8S*o2M,). 0(660). HU(5C_H2)lP0Erl- 0(8so2m), H(6 +Ph)- - - (co) and H(8o+`-Ph). 0( `Po) intramolecular hydrogen bonds. The almost co nstant negative carbonyl frequency shifts (Av) for the title compounds 1-6 with respect to the parent acetophenones 7-14 corroborates the prevalence of the electronic interactions over the -l(y inductive effect of the ot-substituents for the title compounds and gives strong support for the existence of the crossed 0`(`C-O)... S`(1S+02m,) and 0(""S-02) C(`C+O) (charge transfer and electrostatic); 08-) (co P(`i o) and 01`M-OFt)l C(` o), (electrostatic) interactions. 0 2008 Elsevier B.V. All rights reserved.

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This essay is an ideographic study over the capacity of high school students to use the Internet with source criticism, and their attitudes towards this media. It’s a qualitative study whose main purpose is to seek out how the students reflect upon the problems facing them when searching facts and information over the internet.The focus group is six 18 year old high school students, who are studying in a normal sized town in the middle of Sweden, and are about to finish their studies in the program for social sciences. The study was made through interviews, one on one with the students,The results of the analysis have shown that even if students not necessarily use a pre meditated method when searching for information over the internet, they do have a basic understanding of the matter, especially concerning the nature of the source, who published it and why. Not all students made any thorough comparison with other, already established media, such as TV or books, but the analysis made it clear that they more or less deliberately saw the established media as more trustworthy in general. Individuals publishing on the internet, such as bloggers and Wikipedia, are seen with the utmost skepticism while public institutions such as universities and public service TV, are generally trusted as being honest and objective, also when publishing on the internet.

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Idre Fjäll currently has not full control of how visitors experience their site or if it has good usability. I have helped the company to do a usability test on their website to see how and where any improvements can be made on the page before the winter season 2010. I have also done a survey to investigate how users perceive Idre Fjälls website. Ten people of various ages participated in the survey. All test subjects was recorded with both audio and screen activity during the tests. The test consisted of five different tasks to be solved over the internet at Idre fjälls website. Nr 1, 3, 4 and 5 was solved for most without problem. In nr 2, where a booking of a house would be done, here arose a problem in nine tests out of ten. The results show that the site has very good graphic design and information design, but some weaknesses in interaction design. I have worked out proposals on the most significant problems identified during the test.

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Syftet med arbetet var att undersöka hur två pedagoger och två rektorer som arbetar på två olika kommunala förskolor ser på innemiljön och dess påverkan på lek. Det innefattar vilket material som används och hur de har utformat miljön. Vi har använt oss av kvalitativa intervjuer och ostrukturerade observationer för att samla in materialet. Resultat av undersökningen visade att båda förskolorna arbetar aktivt med miljön men att den ena förskolan precis har börjat med sitt arbete. Båda förskolorna arbetade efter samma vision, att ha en miljö som är tillgänglig för bar-nen där materialet är synligt och på barnens nivå. Det är något som också tas upp som viktigt i litteratur och forskning. Faktorer som visade sig ha betydelse för utformingen av miljön var eko-nomi, tid, personalens inställning och barnens ålder.

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Biological evolution is part of the syllabi for Biology and Science in Swedish upper secondary school. In the syllabi, evolution is not only presented as a topic in Biology courses, but is also regarded as a unifying theme. The teacher has a fundamental role in deciding how the national curriculum is translated into the educational situation. This thesis investigates teachers’ accounts of their teaching of evolution in Swedish upper secondary school, describing their understandings of the purpose of teaching and learning evolution as part of biology education. The thesis is based on interviews of teachers teaching the course Biology A, which is compulsory as dictated by the Natural Science Program. The interviews were supplemented with questionnaires. The interviews were orientated towards questions about selection of course content and the reasons for choosing this content. The interviews were focused on teachers experiences based on their own practice. Two aspects of content were examined: (1) the scientific content taught in terms of themes and (2) the socializing value-laden aspects, such as priorities taken by the teachers and the teachers´ overarching aims.   The results showed that teachers described different teaching contents with regard to values, even when the core content of themes was similar. Four different selective traditions for choosing content were identified among teachers. The results are discussed in relation to the context and conditions that the teachers identify as influential on the content chosen. Teachers’ interactions with their students as well as their world views are important for their selection and adjustment of content. There are also indications that teachers’ personal views about purposes are important for selecting the teaching content.

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How folk musicians of today learn to play their instruments is an over-all question in this article. One violin lesson and one guitar lesson have been observed at Framnäs folk high school. Three research questions were formulated. What do the two lessons have in common? What are the differences? How could the folk music education of today be related to the Swedish fiddler movement in the 1920s and other folk music traditions? Theoretically, the interpretation of the results was based on the mimesis theory of Ricoeur. Two teachers and three students participated in the study. The results showed that the lessons were structured in a similar way and dominated by master apprenticeship teaching. The violin teacher showed a more respectful attitude towards the tradition compared to the guitar teacher. Great parts of the manifest ideology of the fiddler movement seems to have become concealed into a latent or frozen ideology in the formal folk music education of today. There seems to be no big differences between learning the music by way of visiting an older fiddler hundred years ago compared to the study of music today at a formal institution.

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About crowding – How the size of our dwellings became a welfare problem Housing policy documents have traditionally been studied by political scientists, resulting in a lack of interest in the private aspects of housing policy. Hence, this paper uses the example of crowding standards to examine how a previously private matter, the size of our dwelling, became a concern of the state. Official governmental documents are analyzed with the help of discourse theory, working on the supposition that the need of the population and the framing of a problem changes over time. The first official standard of crowding, formulated in 1946 argue for larger dwelling size in order to increase the size and quality of the Swedish population. The second standard, formulated in 1965, is based on the assumption that the population, defined as consumers, demands larger sized homes. The final standard, formulated in 1975, claims that larger sized homes is a social right.

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Violence at work as a social problem: a study of the media coverage on workplace violence in Swedish trade union journals 1978–2004 The main purpose of this study was to find out the extent of the unions media coverage on workplace violence and the ways in which the topic was framed. The study shows that the reporting of violence in the workplace described in journals is on a stable level during the period 1978–98. However from the year 2000 and onwards, there is a clear increase in the attention. Four categories of workplace violence were used to identify and recognize different types of violence: intrusive-, consumer-, relationship-and organizational violence. This shows that much of the attention over time has shifted from intrusive violence to organizational violence and consumer violence. What seems to have happened is that workplace violence has become more than just robberies and assaults in the retail business. The stereotypical image of the criminal is challenged by non-traditional criminals like nurses, elderly people and companies. Certain groups, e.g. care workers, come to account for an increasing proportion of attention, both as perpetrators and victims of violence. This study is an important step in understanding the increased reports of workplace violence in Sweden.

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På den svenska marknaden står bag-in-box-vin för över 50 procent av allt vin som säljs och Sverige är det land där bag-in-boxen fått starkast fäste i världen (Fremin, 2012). Det gör att bag-in-box-förpackningen är en stor och betydelsefull produkt för vintillverkare och att ha kunskap om säljande design är viktigt för grafiska formgivare samt övriga involverade företag. Den föreliggande studiens syfte var att undersöka vilka designfaktorer på bagin- box-förpackningar som påverkar konsumenternas val av vin i Sverige. Studien innefattade en visuell kartläggning som ämnade ge en överblick av utbudet på ett Systembolag. Detta genomfördes för att skapa en grund till den webbaserade enkätundersökningen som genomfördes under våren 2015. Resultaten visade att majoriteten av respondenterna valde vin baserat på förpackningens utseende och ansåg att de påverkades främst av färg, typsnitt, illustrationer och varumärken. Resultaten visade också att ju högre vinkunskap konsumenterna hade desto mindre påverkade designen deras val. Kvinnor och män hade generellt olika åsikter angående hur stor påverkan de olika designfaktorerna hade vid valet av bag-in-box-vin. Denna studie är endast ett avstamp till ett ämne som innefattar många påverkande faktorer. Det betyder att mer forskning krävs inom ämnet innan helt sanningsenliga resultat kan fastställas.

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This paper examines the stock price and volume effects surrounding the announcement of constituent changes to the S&P/ASX 200 and four supplementary indices. Between April 2000 and December 2002 additions to (deletions from) the ASX 200 were associated with a significant price rise (fall) over the 10 day period following the market announcement of the change. Deletions were also associated with a significant fall on the announcement date itself These findings were corroborated by significant increases in trading volume over the same intervals, suggesting heavy trading activity by index funds in response to changes to the ASX 200. Following the implementation of these changes, both additions and deletions experienced a significant price reversion, supporting the price pressure hypothesis. By contrast, none of the supplementary indices displayed evidence of stock price or volume effects, which precludes the information and liquidity hypotheses as viable explanations for the findings of this research.