2,635 research outputs found
Measurement of the energy spectrum of cosmic rays at the highest energies using data from Pierre Auger Observatory
We report a measurement of the flux of cosmic rays with unprecedented
precision and statistics using data from the Pierre Auger Observatory. Based on
fluorescence observations in coincidence with at least one station of the
surface detector we derive a spectrum for energies above 1 EeV. We also report
on the energy spectra obtained with the surface detector array. The spectral
features are presented in detail and the impact of systematic uncertainties on
these features are addressed.Comment: 6 pages, 8 figures, UHECR 2012 Symposium, CERN, Feb. 201
Origin and physics of the highest energy cosmic rays: What can we learn from Radio Astronomy?
Here in this lecture we will touch on two aspects, one the new radio methods
to observe the effects of high energy particles, and second the role that radio
galaxies play in helping us understand high energy cosmic rays. We will focus
here on the second topic, and just review the latest developments in the first.
Radio measurements of the geosynchrotron radiation produced by high energy
cosmic ray particles entering the atmosphere of the Earth as well as radio
\v{C}erenkov radiation coming from interactions in the Moon are another path;
radio observations of interactions in ice at the horizon in Antarctica is a
related attempt. Radio galaxy hot spots are prime candidates to produce the
highest energy cosmic rays, and the corresponding shock waves in relativistic
jets emanating from nearly all black holes observed. We will review the
arguments and the way to verify the ensuing predictions. This involves the
definition of reliable samples of active sources, such as black holes, and
galaxies active in star formation. The AUGER array will probably decide within
the next few years, where the highest energy cosmic rays come from, and so
frame the next quests, on very high energy neutrinos and perhaps other
particles.Comment: 11 pages, To appear in Proceedings of International School of
Astrophysics at Ultra-high Energies, 20-27 June, 2006, Erice, Sicily, Ital
Finasteride as a model for personalized medicine
The side effects of Finasteride are currently a subject of controversy. Some studies report minor or acceptable adverse effects, which decrease after a variable period of time so that they do not necessitate terminating Finasteride administration. However, several clinical and neuro-endocrine studies show that some adverse effects persist indefinitely in the form of post-Finasteride syndrome, even after the drug cessation. This paper presents a possible explanation for these inconsistent findings. First, the study design of either informing or not informing patients prior therapy about possible adverse effects can influence the incidence and magnitude of reported adverse effects. Second, structural and information dichotomies of the brain generate four distinct neuronal networks, which are activated through specific cerebral neuromodulators and that are able to support four distinct minds within an individual body. As a conclusion, the “mind psychophysiology” and the corresponding mental impairments differ across individuals, such that not only the prediction of adverse effects should be addressed from a more individualized medical perspective, but also the therapeutic strategies could be tailored to the four distinct mental profiles described. It is a personalized approach that would be applicable to several interrelated domains of neuroscience, like psychology, psychiatry and sexuality. Finally, this perspective may represent a starting point for a more individualized understanding of mental events, perhaps even a step forward in the understanding of the mind-body problem
How are firms affected by the crisis and how do they react?
The recession started in 2008 constituted a massive shock to consumers and most firms all over the Western World. Firms were hit on their sales and finances. However, little is known on how badly they were hit and how they coped with the difficulties. This paper gives a rare and fairly early glimpse on how private Danish firms were hit and how they adjusted in order to survive the crisis. The first phase of the recession led to the largest loss of jobs since the oil crisis in Denmark. Four years into the recession we see that larger firms are gradually creating jobs again, although the overall job growth is still negative (Statistics Denmark, 2012). Consequently we present an assessment of factors that have been important in explaining why some firms have been able to recreate jobs and others have not. Especially, we point at the critical role of access to credit in creating and destroying jobs. The paper is based on a survey run on all Danish firms with more than 20 employees in November and December 2011
Layered water Cherenkov detector for the study of ultra high energy cosmic rays
We present a new design for the water Cherenkov detectors that are in use in
various cosmic ray observatories. This novel design can provide a significant
improvement in the independent measurement of the muonic and electromagnetic
component of extensive air showers. From such multi-component data an event by
event classification of the primary cosmic ray mass becomes possible. According
to popular hadronic interaction models, such as EPOS-LHC or QGSJetII-04, the
discriminating power between iron and hydrogen primaries reaches Fisher values
of 2 or above for energies in excess of eV with a detector
array layout similar to that of the Pierre Auger Observatory.Comment: 17 pages, 15 figures, submitted to Nuclear Instruments and Methods
Development of cutter for printed circuit board using hydraulic principle
Cutter was known since long times ago as something that was use to cut the thing into smaller piece. Starting from the usual rock at the rock age till the high
technology cutter which was make from the precious and valuable material like diamond at this modern age, the cutter was develop to make our daily life more easier and easier. This project is proposed to design and fabricate a cutter as benefit to cut the printed circuit board, the board which contains cuprum as a trace to connect the electricity current to the electronic component like resistors and capacitors. The printed circuit board was widely used in modern electronic and electric component like radio and computer because it can minimize the space and reduce the manufacturing cost by assemble all electronic components together. The usual way to cut the printed circuit board is by using hand because the sensitive of it. By develop the cutter it will make the way to cut the printed circuit board is more efficient without give the damage to the board. In this project, the main purpose of study is to develop the cutter to make sure the cutter can achieve it objective. Developments of cutter are starting by choosing the right cutter's material then design and finally fabricate the cutter
Metabolic alterations in experimental models of depression
Introduction: Major depressive disorder is one of the most prevalent psychiatric disorders and is associated with a severe impact on the personal functioning, thus with incurring significant direct and indirect costs. The presence of depression in patients with medical comorbidities increases the risks of myocardial infarction and decreases diabetes control, and adherence to treatment. The mechanism through which these effects are produced is still uncertain. Objectives of this study were to evaluate the metabolic alterations in female Wistar rats with induced depression, with and without administration of Agomelatine. The methods included two experiments. All data were analyzed by comparison with group I (control), and with each other. In the first experiment we induced depression by: exposure to chronic mild stress-group II; olfactory bulbectomy-group III; and exposure to chronic mild stress and hyperlipidic/ hyper caloric diet-group IV. The second experiment was similar with the first but the rats received Agomelatine (0.16mg/ animal): group V (depression induced through exposure to chronic mild stress), VI (depression induced through olfactory bulbectomy) and VII (depression induced through exposure to chronic mild stressing hyperlipidic/ hypercaloric diet). Weight, cholesterol, triglycerides and glycaemia were measured at day 0 and 28, and leptin value was measured at day 28. The results in the 1st experiment revealed significant differences (pconclusion, significant correlations were found between high level of triglycerides and depression induced by chronic stress and olfactory bulbectomy. Agomelatine groups had a lower increase of triglycerides levels
Uptake of one and two molecules of CO2 by the molybdate dianion: a soluble, molecular oxide model system for carbon dioxide fixation
Tetrahedral [MoO4][superscript 2−] readily binds CO[subscript 2] at room temperature to produce a robust monocarbonate complex, [MoO[subscript 3](κ[superscript 2]-CO[subscript 3])][superscript 2−], that does not release CO[subscript 2] even at modestly elevated temperatures (up to 56 °C in solution and 70 °C in the solid state). In the presence of excess carbon dioxide, a second molecule of CO[subscript 2] binds to afford a pseudo-octahedral dioxo dicarbonate complex, [MoO[subscript 2](κ[superscript 2]-CO[subscript 3])[subscript 2][superscript 2−], the first structurally characterized transition-metal dicarbonate complex derived from CO[subscript 2]. The monocarbonate [MoO[subscript 3](κ[superscript 2]-CO[subscript 3])][superscript 2−] reacts with triethylsilane in acetonitrile under an atmosphere of CO[subscript 2] to produce formate (69% isolated yield) together with silylated molybdate (quantitative conversion to [MoO[subscript 3](OSiEt[subscript 3])][superscript −], 50% isolated yield) after 22 hours at 85 °C. This system thus illustrates both the reversible binding of CO[subscript 2] by a simple transition-metal oxoanion and the ability of the latter molecular metal oxide to facilitate chemical CO[subscript 2] reduction.Saudi Basic Industries CorporationSpain. Ministerio de Educación, Cultura y DeporteSpain. Ministerio de Economía y Competitividad (CTQ2012-36966)National Science Foundation (U.S.) (CHE-1111357)National Science Foundation (U.S.) (CHE- 0946721
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