Constraints on the origin of cosmics rays above '10 POT. 18' eV from large-scale anisotropy searches in data of the Pierre Auger observatory

A thorough search for large-scale anisotropies in the distribution of arrival directions of cosmic rays detected above '10 POT. 18' eV at the Pierre Auger Observatory is reported. For the first time, these large-scale anisotropy searches are performed as a function of both the right ascension and the declination and expressed in terms of dipole and quadrupole moments.Within the systematic uncertainties, no significant deviation from isotropy is revealed. Upper limits on dipole and quadrupole amplitudes are derived under the hypothesis that any cosmic ray anisotropy is dominated by such moments in this energy range. These upper limits provide constraints on the production of cosmic rays above '10 POT. 18' eV, since they allow us to challenge an origin from stationary galactic sources densely distributed in the galactic disk and emitting predominantly light particles in all directions.

Molecular origin of charge traps in polyfluorene-based semiconductors

The comprehensive control of morphology and structure is of extreme importance in semiconducting polymers when used as active layers in optoelectronic devices. In the work reported here, a systematic investigation of the structural and dynamical properties of poly(9,9-di-n-octyl-fluorene-alt-benzothiadiazole), known as F8BT, and their correlation with electrical properties is presented when the material is used as an active layer in optoelectronic devices. By means of X-ray diffraction, one observes that in thick layer films (thickness of about 4 μm) grown by drop-cast deposition, a solvent induced crystalline phase exists which evolves to a stable phase as the temperature is raised. This was not observed in thin films (thickness of about 250 nm) prepared by spin-coating within the investigated temperature range. By modeling the current-voltages characteristics of both thick and thin film devices, important information on the influence of crystallization on the trapping states could be drawn. Furthermore, the temperature dependence of the charge carrier mobility was found to be closely related to that of the molecular relaxation processes. The understanding of the nature of such molecular relaxations, measured by solid-state nuclear magnetic resonance methods, allows one to understand the importance of molecular relaxations and microstructure changes on the trap states of the system.

Origin of the groundwater salinization in La Aldea coastal aquifer (Gran Canaria, Canary Islands)

[EN] Groundwater chemistry in La Aldea aquifer (Gran Canaria, Canary Islands) shows high contents of chloride and nitrate ions. The salinization process has been modelled using the geochemical data, taking into account the results of a previous flow model. The results allow to identify the salinity of the recharge from the rainfall under aridity conditions and the irrigation returns like the main causes of the groundwater salinization.

Nature and origin of ultramafic lamprophyres and carbonatites from the borders of the Labrador Sea

Die Ränder des Labrador Meeres wurden während des späten Neoproterozoikums intensiv von karbonatreichen silikatischen Schmelzen durchsetzt. Diese Schmelzen bildeted sich bei Drucken zwischen ca. 4-6 GPa (ca. 120-180 km Tiefe) an der Basis der kontinentalen Mantel-Lithosphäre. Diese Magmengenerierung steht in zeitlichem und räumlichem Zusammenhang mit kontinentalen Extensionsprozessen, welche zu beiden Seiten des sich öffnenden Iapetus-Ozeans auftraten.

Origin of cold gas and dust in massive elliptical galaxies

The recent availability of multi-wavelength data revealed the presence of large reservoirs of warm and cold gas and dust in the innermost regions of the majority of massive elliptical galaxies. To prove an internal origin of cold and warm gas, the investigation of the spatially distributed cooling process which occurs because of non-linear density perturbations and subsequent thermal instabilities is of crucial importance. The first goal of this work of thesis is to investigate the internal origin of warm and cold phases. Numerical simulations are the powerful tool of analysis. The way in which a spatially distributed cooling process originates has been examined and the off-centre amount of gas mass which cools when different and differently characterized AGN feedback mechanisms operate has been quantified. This thesis demonstrates that the aforementioned non-linear density perturbations originate and develop from AGN feedback mechanisms in a natural fashion. An internal origin of the warm phase from the once hot gas is shown to be possible. Computed velocity dispersions of ionized and hot gas are similar. The cold gas as well can originate from the cooling process: indeed, it has been estimated that the surrounding stellar radiation, which is one of the most feasible sources of ionization of the warm gas, does not manage to keep ionized all the gas at 10^4 K. Therefore, cooled gas does undergo a further cooling which can lead the warm phase to lower temperatures. However, the gas which has cooled from the hot phase is expected to be dustless; nonetheless, a large fraction of early type galaxies has detectable dust in their cores, both concentrated in filamentary and disky structures and spread over larger regions. Therefore a regularly rotating disk of cold and dusty gas has been included in the simulations. A new quantitative investigation of the spatially distributed cooling process has therefore been essential: the contribution of the included amount of dust which is embedded in the cold gas does have a role in promoting and enhancing the cooling. The fate of dust which was at first embedded in cold gas has been investigated. The role of AGN feedback mechanisms in dragging (if able) cold and dusty gas from the core of massive ellipticals up to large radii has been studied.

Origin of the spin Seebeck effect

Der Spin Seebeck Effekt repräsentiert einen neuartigen Spin kalorischen Effekt mit vorteilhaften und aussichtsreichen Eigenschaften für Anwendungen in den Gebieten der Spintronik und Thermoelektrik.rnIn dieser Arbeit präsentieren wir eine umfangreiche Untersuchung des Spin Seebeck Effekts in isolierenden, magnetischen Granaten und geben Antworten zum kontrovers diskutierten Ursprung des Effekts. Um dieses Ziel zu erreichen, haben wir die Abhängigkeit des Spin Seebeck Effekts von der Dicke des Ferromagneten, der Temperatur, der Stärke des magnetisches Feldes, der Grenzflächen und des Detektormaterials, sowie Kombinationen dieser Parameter gemessen. Im Zuge dessen haben wir das Wachstum der untersuchten magnetischen Granate optimiert und eine umfassende Analyse der strukturellen und magnetischen Parameter durchgeführt, um Einflüsse der Probenqualität auszuschließen. Des Weiteren zeigte eine Untersuchung des magnetoresistiven Effekts, welcher als mögliche Ursache des Effekts galt, in Kombination mit einer Studie des Messaufbaus, dass parasitäre Einflüsse auf das Messergebnis ausgeschlossen werden können. Unsere Ergebnisse zeigen, dass der Spin Seebeck Effekt mit zunehmender Dicke des Ferromagneten eine Sättigung des Signals aufweist. Diese hängt zudem von der Temperatur ab, da mit abnehmender Temperatur die Sättigung erst bei dickeren Filmen auftritt. Außerdem fanden unsere Messungen ein Maximum des Spin Seebeck Effekts für Temperaturen unterhalb der Raumtemperatur, welcher sowohl von der Dicke des Materials als auch der Magnetfeldstärke und dem Detektormaterial beeinflusst wird. In Messungen bei hohen magnetischen Feldstärken beobachteten wir eine Unterdrückung des Messsignals, dessen Ursache mithilfe von Simulationen auf den magnonischen Ursprung des Spin Seebeck Effekts zurückgeführt werden kann. Dies unterstreicht, dass der Effekt auf vom Ferromagneten emittierten Magnonen basiert. Im letzten Abschnitt dieser Arbeit präsentieren wir Messungen in einem bislang nicht untersuchten ferrimagnetischen Material, welche zwei Vorzeichenwechsel des Spin Seebeck Effekts als Funktion der Temperatur aufzeigen. Dieses bisher unbekannte Signalverhalten betont, dass der Effekt aus einem komplexen Zusammenspiel der magnonischen Moden resultiert und zusätzlich vom Detektormaterial abhängt.rnSomit tragen unsere Ergebnisse und Beobachtungen im hohen Maße zur Beantwortung der Frage nach dem Ursprungs des Spin Seebeck Effekts bei und zeigen neuartige bisher nicht beobachtete Effekte, welche ein neues Kapitel für das Gebiet der Spin Kaloritronik eröffnen.

What does local tenderness say about the origin of pain? An investigation of cervical zygapophysial joint pain

BACKGROUND: Mechanical pain sensitivity is assessed in every patient with pain, either by palpation or by quantitative pressure algometry. Despite widespread use, no studies have formally addressed the usefulness of this practice for the identification of the source of pain. We tested the hypothesis that assessing mechanical pain sensitivity distinguishes damaged from healthy cervical zygapophysial (facet) joints. METHODS: Thirty-three patients with chronic unilateral neck pain were studied. Pressure pain thresholds (PPTs) were assessed bilaterally at all cervical zygapophysial joints. The diagnosis of zygapophysial joint pain was made by selective nerve blocks. Primary analysis was the comparison of the PPT between symptomatic and contralateral asymptomatic joints. The secondary end points were as follows: differences in PPT between affected and asymptomatic joints of the same side of patients with zygapophysial joint pain; differences in PPT at the painful side between patients with and without zygapophysial joint pain; and sensitivity and specificity of PPT for 2 different cutoffs (difference in PPT between affected and contralateral side by 1 and 30 kPa, meaning that the test was considered positive if the difference in PPT between painful and contralateral side was negative by at least 1 and 30 kPa, respectively). The PPT of patients was also compared with the PPT of 12 pain-free subjects. RESULTS: Zygapophysial joint pain was present in 14 patients. In these cases, the difference in mean PPT between affected and contralateral side (primary analysis) was −6.2 kPa (95% confidence interval: −19.5 to 7.2, P = 0.34). In addition, the secondary analyses yielded no statistically significant differences. For the cutoff of 1 kPa, sensitivity and specificity of PPT were 67% and 16%, respectively, resulting in a positive likelihood ratio of 0.79 and a diagnostic confidence of 38%. When the cutoff of 30 kPa was considered, the sensitivity decreased to only 13%, whereas the specificity increased to 95%, resulting in a positive likelihood ratio of 2.53 and a diagnostic confidence of 67%. The PPT was significantly lower in patients than in pain-free subjects (P < 0.001). CONCLUSIONS: Assessing mechanical pain sensitivity is not diagnostic for cervical zygapophysial joint pain. The finding should stimulate further research into a diagnostic tool that is widely used in the clinical examination of patients with pain.

3D bloodstain pattern analysis: ballistic reconstruction of the trajectories of blood drops and determination of the centres of origin of the bloodstains

For crime scene investigation in cases of homicide, the pattern of bloodstains at the incident site is of critical importance. The morphology of the bloodstain pattern serves to determine the approximate blood source locations, the minimum number of blows and the positioning of the victim. In the present work, the benefits of the three-dimensional bloodstain pattern analysis, including the ballistic approximation of the trajectories of the blood drops, will be demonstrated using two illustrative cases. The crime scenes were documented in 3D, using the non-contact methods digital photogrammetry, tachymetry and laser scanning. Accurate, true-to-scale 3D models of the crime scenes, including the bloodstain pattern and the traces, were created. For the determination of the areas of origin of the bloodstain pattern, the trajectories of up to 200 well-defined bloodstains were analysed in CAD and photogrammetry software. The ballistic determination of the trajectories was performed using ballistics software. The advantages of this method are the short preparation time on site, the non-contact measurement of the bloodstains and the high accuracy of the bloodstain analysis. It should be expected that this method delivers accurate results regarding the number and position of the areas of origin of bloodstains, in particular the vertical component is determined more precisely than using conventional methods. In both cases relevant forensic conclusions regarding the course of events were enabled by the ballistic bloodstain pattern analysis.

An unusual cause of hemoptysis--aberrant origin of the left pulmonary artery from the ascending aorta in the adult

Aberrant origin of a pulmonary artery from the ascending aorta is an uncommon congenital vascular malformation with poor survival without surgery. In this case report, we describe the unusual late diagnosis of this congenital malformation in an otherwise asymptomatic young man presenting with mild hemoptysis. We review the natural and modified history of this defect and the relevant aspects of follow-up in adult life.