Dehydration Melting and Proterozoic Granite Petrogenesis in a Collisional Orogen-A Case from the Svecofennian of Southern Finland

Dehydration melting of metasupracrustal rocks at mid- to deep-crustal levels can generate water undersaturated granitic melt. In this study, we evaluate the potential of similar to 1.89-1.88 Ga metasupracrustal rocks of the Precambrian of southern Finland as source rocks for the 1.86-1.79 Ga late-orogenic leucogranites in the region, using the Rhyolite-MELTS approach. Melt close in composition to leucogranite is produced over a range of realistic pressures (5 to 8 kbar) and temperatures (800 to 850 degrees C), at 20%-30% of partial melting, allowing separation of melt from unmelted residue. The solid residue is a dry, enderbitic to charnoenderbitic ganulite depleted in incompatible components, and will only yield further melt above 1 000-1 050 degrees C, when rapidly increasing fractions of increasingly calcic (granodioritic to tonalitic) melts are formed. The solid residue after melt extraction is incapable of producing syenogranitic magmas similar to the Mid-Proterozoic, A-type rapakivi granites on further heating. The granitic fraction of the syenogranitic rapakivi complexes must thus have been formed by a different chain of processes, involving mantle-derived mafic melts and melts from crustal rock types not conditioned by the preceding late-orogenic Svecofennian anatexisPeer reviewe

Cefalea racimos en una niña de 3 años

Summary. Introduction. Cluster headache is a rare disorder in childhood. We identified, in the literature, 64 cases of cluster headache starting at or before 18 years (only 17 of them began before 10 years old). All patients met the criteria of the International Headache Society. Russell et al demonstrated recently that the cluster headache is an inherited disorder in some families. They conclude that the gene is present in 3 to 4% of males and 7 to 10% of females with cluster headache and that it has an autossomal dominant transmission. Clinical case. The authors report the clinical case of a five-year-old child with cluster headache starting at three years. This paper reviews the differential diagnosis and the treatment of cluster headach

Effects of using different plasmonic metals in metal/dielectric/metal subwavelength waveguides on guided dispersion characteristics

The fundamental guided dispersion characteristics of guided light in a subwavelength dielectric slit channel embedded by two different plasmonic metals are investigated when varying the gap width. As a result, an overall and salient picture of the guided dispersion characteristics is obtained over a wide spectrum range below and above the plasma frequencies of the two different plasmonic metals, which is important preliminary information for analyzing this type of subwavelength waveguide. In particular, the effects of using two different metals on the guided mode dispersions are emphasized in comparison with the effects of using the same plasmonic metal cladding.Comment: 13 pages, 3 figures, typos corrected, reference added, text modifie

Characterization and Modeling of Non-Uniform Charge Collection in CVD Diamond Pixel Detectors

A pixel detector with a CVD diamond sensor has been studied in a 180 GeV/c pion beam. The charge collection properties of the diamond sensor were studied as a function of the track position, which was measured with a silicon microstrip telescope. Non-uniformities were observed on a length scale comparable to the diamond crystallites size. In some regions of the sensor, the charge drift appears to have a component parallel to the sensor surface (i.e., normal to the applied electric field) resulting in systematic residuals between the track position and the hits position as large as 40 $\mu$m. A numerical simulation of the charge drift in polycrystalline diamond was developed to compute the signal induced on the electrodes by the electrons and holes released by the passing particles. The simulation takes into account the crystallite structure, non-uniform trapping across the sensor, diffusion and polarization effects. It is in qualitative agreement with the data. Additional lateral electric field components result from the non-uniform trapping of charges in the bulk. These provide a good explanation for the large residuals observed.Comment: Accepted by Nucl. Instr. and Met

Simulations of electromagnetic effects in high frequency capacitively coupled discharges using the Darwin approximation

The Darwin approximation is investigated for its possible use in simulation of electromagnetic effects in large size, high frequency capacitively coupled discharges. The approximation is utilized within the framework of two different fluid models which are applied to typical cases showing pronounced standing wave and skin effects. With the first model it is demonstrated that Darwin approximation is valid for treatment of such effects in the range of parameters under consideration. The second approach, a reduced nonlinear Darwin approximation-based model, shows that the electromagnetic phenomena persist in a more realistic setting. The Darwin approximation offers a simple and efficient way of carrying out electromagnetic simulations as it removes the Courant condition plaguing explicit electromagnetic algorithms and can be implemented as a straightforward modification of electrostatic algorithms. The algorithm described here avoids iterative schemes needed for the divergence cleaning and represents a fast and efficient solver, which can be used in fluid and kinetic models for self-consistent description of technical plasmas exhibiting certain electromagnetic activity

Síntesis de monómeros funcionalizados para el desarrollo de polímeros degradables con respuesta a estímulos y estudio bibliográfico de últimos avances en su aplicación como nanotransportadores de liberación controlada

Los nanotransportadores presentan diversas características que permiten eludir algunos problemasasociados a terapias médicas invasivas y con notables efectos secundarios. Los copolímeros bloqueanfífilos basados en policarbonatos son una prometedora alternativa por su capacidad de formarautoensamblados en agua que encapsulen y transporten fármacos, por la posibilidad de integrarunidades con respuesta a estímulos que faciliten una liberación controlada, así como por subiocompatibilidad y biodegradabilidad.La utilización de carbonatos cíclicos derivados del ácido bis-MPA para la síntesis de policarbonatosalifáticos es especialmente interesante por la posibilidad de incorporar cadenas laterales a través desu grupo carboxilo. Además, la polimerización por apertura de anillo de estos monómeros presentaun alto control de la masa molecular y dispersidad. Los carbonatos cíclicos con grupos propargilo yalilo permiten obtener copolímeros en los que es posible anexionar unidades con respuesta aestímulos.En este trabajo, en primer lugar se ha elaborado un estudio de las últimas referencias en las que seemplean los monómeros MPC (carbonato cíclico con el grupo propargilo) y MAC (carbonato cíclicocon el grupo alilo) para la preparación de nanotransportadores con liberación controlada. Sucopolimerización conduciría a la síntesis de materiales con versatilidad en su funcionalización.Siguiendo esta línea, se ha propuesto una ruta para la obtención de copolímeros bloque yestadísticos basada en la combinación de ambos, que permitiría la obtención de policarbonatostodavía no sintetizados en la literatura, con capacidad de ser funcionalizados ortogonalmente conunidades con foto y termo-respuesta. Para afrontar estos materiales, se han sintetizado losmonómeros necesarios, optimizando los procedimientos sintéticos y comparando la ruta másutilizada en la bibliografía con otras alternativas. Los resultados han llevado a la obtención losmonómeros MPC y MAC, así como a la planificación de su futura polimerización, copolimerización yposterior funcionalización de acuerdo al estudio bibliográfico.<br /

Different grain grinding methods affect detection of Fusarium graminearum DNA and mycotoxins

Fusarium graminearum is the most important deoxynivalenol (DON) producing species in northern Europe and Asia. The highest DON levels in Finland have been found in oat grain, and DNA levels of F. graminearum are in agreement with DON levels, when DON is measured by accredited GC-MS. In addition to DON, 3ADON is present in Finnish grain samples. Large variations in DON content and amounts of F graminearum DNA, and poor coefficient of determination (R-2) between these, have been detected in oat grain when the RIDA (R) QUICKSCAN kit results for DON content have been used. This study confirmed that the coefficient of determination was usually less when DNA or DON were extracted from oat flour, which was not ground with 0.8 mm or 1 mm sieves. DON levels obtained with the Rida Quick method were usually higher than those obtained with accredited GC-MS in Finnish oat, barley and wheat samples. The homogenization of the oat flour by sieving is therefore likely to be connected to the variations in DON detection. Amounts of F graminearum DNA and DON close to legislative limits should be reconfirmed with accredited quantitative analyses

Effect of the Coulomb repulsion on the {\it ac} transport through a quantum dot

We calculate in a linear response the admittance of a quantum dot out of equilibrium. The interaction between two electrons with opposite spins simultaneously residing on the resonant level is modeled by an Anderson Hamiltonian. The electron correlations lead to the appearence of a new feature in the frequency dependence of the conductance. For certain parameter values there are two crossover frequencies between a capacitive and an inductive behavior of the imaginary part of the admittance. The experimental implications of the obtained results are briefly discussed.Comment: 13 pages, REVTEX 3.0, 2 .ps figures from [email protected], NUB-308

Time-Dependent Current Partition in Mesoscopic Conductors

The currents at the terminals of a mesoscopic conductor are evaluated in the presence of slowly oscillating potentials applied to the contacts of the sample. The need to find a charge and current conserving solution to this dynamic current partition problem is emphasized. We present results for the electro-chemical admittance describing the long range Coulomb interaction in a Hartree approach. For multiply connected samples we discuss the symmetry of the admittance under reversal of an Aharonov-Bohm flux.Comment: 22 pages, 3 figures upon request, IBM RC 1971