533 research outputs found

    Geology of the Tertiary Sediments in the Northwestern End of the Wind River Basin

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    The lithology of the majority of the beds of the northwestern end of the Wind River Basin varies greatly within short distances. A few individual beds retain their character over a comparatively large area. These beds were traced for more than ten miles along the north side of Wind River Valley. The topography of the area is strikingly different at various locations, due to glaciation, changes in lithology, and elevation above the Wind River. Eleven stratigraphic sections were carefully measured and described. These sections were correlated on the basis of trigonometric projection, Stratigraphic sequence, and lithologic similarity. Measurements and traverses were made with a transit to insure accuracy. It is the writer\u27s hope that this article will prove of value to future students of the area

    Optimizing Collection of Trace Biological Samples from Vehicle Headrests

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    Tape-lifting and swabbing are two methods commonly used for collecting biological samples in the United Kingdom and United States to investigate vehicle crimes. Determining the optimal collection method may lead to an increase in generating DNA profiles and crime-solving. The objective of this study is to evaluate the efficiency of adhesive tape and the double-swab collection methods for investigating vehicle crimes with possible touch DNA samples. Two experiments were conducted to evaluate the use of tape-lifts and swabs on spiked common vehicle fabric materials. The efficiency of recovery between the two collection methods was performed using qPCR. The results from the collection of fabric materials indicated tape-lifts outperformed swabbing on cloth and vinyl substrates, while swabbing resulted in comparable recovery on leather substrates. By optimizing sample collection techniques, we aim to aid not only investigations involving vehicles but also other crimes with touch DNA evidence present

    Some thoughts on theoretical physics

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    Some thoughts are presented on the inter-relation between beauty and truth in science in general and theoretical physics in particular. Some conjectural procedures that can be used to create new ideas, concepts and results are illustrated in both Boltzmann-Gibbs and nonextensive statistical mechanics. The sociological components of scientific progress and its unavoidable and benefic controversies are, mainly through existing literary texts, briefly addressed as well.Comment: Short essay based on the plenary talk given at the International Workshop on Trends and Perspectives in Extensive and Non-Extensive Statistical Mechanics, held in November 19-21, 2003, in Angra dos Reis, Brazil. To appear in a Physica A special volume (2004) edited by E.M.F. Curado, H.J. Herrmann and M. Barbosa. 23 pages, including 3 figures. The new version has 25 pages and the same figures. The texts by Saramago and by Bersanelli are now translated into English. A few typos and minor improvements are included as wel

    Revision of Solar Spicule Classification

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    Solar spicules are the fundamental magnetic structures in the chromosphere and considered to play a key role in channelling the chromosphere and corona. Recently, it was suggested by De Pontieu et al. that there were two types of spicules with very different dynamic properties, which were detected by space- time plot technique in the Ca ii H line (3968 A) wavelength from Hinode/SOT observations. 'Type I' spicule, with a 3-7 minute lifetime, undergoes a cycle of upward and downward motion; in contrast, 'Type II' spicule fades away within dozens of seconds, without descending phase. We are motivated by the fact that for a spicule with complicated 3D motion, the space-time plot, which is made through a slit on a fixed position, could not match the spicule behavior all the time and might lose its real life story. By revisiting the same data sets, we identify and trace 105 and 102 spicules in quiet sun (QS) and coronal hole (CH), respectively, and obtain their statistical dynamic properties. First, we have not found a single convincing example of 'Type II' spicules. Secondly, more than 60% of the identified spicules in each region show a complete cycle, i.e., majority spicules are 'Type I'. Thirdly, the lifetime of spicules in QS and CH are 148 s and 112 s, respectively, but there is no fundamental lifetime difference between the spicules in QS and CH reported earlier. Therefore, the suggestion of coronal heating by 'Type II' spicules should be taken with cautions. Subject headings: Sun: chromosphere Sun:transition region Sun:coronaComment: accepted by Ap

    The Peaceful Atom Comes to Campus

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    Youthful idealism, institutional ambition, and Cold War sensibilities all helped shape the Michigan Memorial–Phoenix Project, the University of Michigan’s tribute to fallen World War II soldiers.</jats:p

    On increasing global temperatures: 75 years after Callendar

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    In 1938, Guy Stewart Callendar was the first to demonstrate that the Earth’s land surface was warming. Callendar also suggested that the production of carbon dioxide by the combustion of fossil fuels was responsible for much of this modern change in climate. This short note marks the 75th anniversary of Callendar’s landmark study and demonstrates that his global land temperature estimates agree remarkably well with more recent analyses

    The Code of Protest. Images of Peace in the West German Peace Movements, 1945-1990

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    The article examines posters produced by the peace movements in the Federal Republic of Germany during the ColdWar, with an analytical focus on the transformation of the iconography of peace in modernity. Was it possible to develop an independent, positive depiction of peace in the context of protests for peace and disarmament? Despite its name, the pictorial selfrepresentation of the campaign ‘Fight against Nuclear Death’ in the late 1950s did not draw on the theme of pending nuclear mass death. The large-scale protest movement in the 1980s against NATO’s 1979 ‘double-track’ decision contrasted female peacefulness with masculine aggression in an emotionally charged pictorial symbolism. At the same time this symbolism marked a break with the pacifist iconographic tradition that had focused on the victims of war. Instead, the movement presented itself with images of demonstrating crowds, as an anticipation of its peaceful ends. Drawing on the concept of asymmetrical communicative ‘codes’ that has been developed in sociological systems theory, the article argues that the iconography of peace in peace movement posters could not develop a genuinely positive vision of peace, since the code of protest can articulate the designation value ‘peace’ only in conjunction with the rejection value ‘war’

    The 'law of requisite variety' may assist climate change negotiations:a review of the Kyoto and Durban meetings

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    Ashby wrote about cybernetics, during which discourse he described a Law that attempts to resolve difficulties arising in complex situations – he suggested using variety to combat complexity. In this paper, we note that the delegates to the UN Framework Convention on Climate Change (UNFCCC) meeting in Kyoto, 1997, were offered a ‘simplifying solution’ to cope with the complexity of discussing multiple pollutants allegedly contributing to ‘climate change’. We assert that the adoption of CO2eq has resulted in imprecise thinking regarding the ‘carbon footprint’ – that is, ‘CO2’ – to the exclusion of other pollutants. We propose, as Ashby might have done, that the CO2eq and other factors within the ‘climate change’ negotiations be disaggregated to allow careful and specific individual solutions to be agreed on each factor. We propose a new permanent and transparent ‘action group’ be in charge of agenda setting and to manage the messy annual meetings. This body would be responsible for achieving accords at these annual meetings, rather than forcing this task on national hosts. We acknowledge the task is daunting and we recommend moving on from Ashby's Law to Beer's Viable Systems approach

    Eutectic Colony Formation: A Stability Analysis

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    Experiments have widely shown that a steady-state lamellar eutectic solidification front is destabilized on a scale much larger than the lamellar spacing by the rejection of a dilute ternary impurity and forms two-phase cells commonly referred to as `eutectic colonies'. We extend the stability analysis of Datye and Langer for a binary eutectic to include the effect of a ternary impurity. We find that the expressions for the critical onset velocity and morphological instability wavelength are analogous to those for the classic Mullins-Sekerka instability of a monophase planar interface, albeit with an effective surface tension that depends on the geometry of the lamellar interface and, non-trivially, on interlamellar diffusion. A qualitatively new aspect of this instability is the occurence of oscillatory modes due to the interplay between the destabilizing effect of the ternary impurity and the dynamical feedback of the local change in lamellar spacing on the front motion. In a transient regime, these modes lead to the formation of large scale oscillatory microstructures for which there is recent experimental evidence in a transparent organic system. Moreover, it is shown that the eutectic front dynamics on a scale larger than the lamellar spacing can be formulated as an effective monophase interface free boundary problem with a modified Gibbs-Thomson condition that is coupled to a slow evolution equation for the lamellar spacing. This formulation provides additional physical insights into the nature of the instability and a simple means to calculate an approximate stability spectrum. Finally, we investigate the influence of the ternary impurity on a short wavelength oscillatory instability that is already present at off-eutectic compositions in binary eutectics.Comment: 26 pages RevTex, 14 figures (28 EPS files); some minor changes; references adde
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