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

Impact of work from home on work-life balance: Mediating effects of work-family conflict and work motivation

In the aftermath of the recent pandemic, organizations around the world had the opportunity to assess the benefits and drawbacks of allowing the bulk of their employees to work from home (WFH). As a result, many organizations realize that by using technology, it is possible to shift a significant percentage of their workforce to permanently function from any location without being physically present at a designated workplace. Although the economic benefits for organizations that allow WFH seem to be clear, how factors related to perceptions of employees such as their work motivation (WM) and their work-life balance (WLB) caused by blurred boundaries between work and family at home are not clearly understood. Therefore, the primary goal of this study is to determine how WFH impacts WLB through the possible mediating effects of work-family conflict (WFC) and WM. A cross-sectional survey instrument was developed using Likert type measurement scales that were adopted from top-tier journals. The data was collected through convenient sampling from 249 managerial and non-managerial employees in Omani business organizations. The relationships were tested through structural equation modeling. The results indicate that WFH increases WFC and WM, while the relationship between WFH and WLB is mediated by WFC, but not by WM. The findings of this study have implications for both theory and practice

The basal dunite of the Precambrian mafic-ultramafic Narankavaara intrusion : Petrogenetic considerations and implications to exploration

Several mafic-ultramafic layered intrusions were emplaced in the Fennoscandian Shield during wide-spread mantle-sourced magmatism at 2.5-2.4 Ga. The Narankavaara intrusion (surface area 5 x 30 km(2)), northeastern Finland, contains a 1.5-2 km thick basal dunite (not dated), and a 1.5 km thick layered series (2436 +/- 5 Ma). A newly discovered marginal series between the basal dunite and the layered series indicates that the basal dunite is older, and highlights the need for further study on their relationship. Along its southern basement contact, the basal dunite contains a 200-300 m thick zone of olivine ortho- and mesocumulates, but the bulk of it is composed of olivine adcumulates and lesser olivine-orthopyroxene heteradcumulates. Based on whole-rock geochemistry, the basal dunite is divided into a low-Fe zone (average FeOt 10.2 wt% and Ni 2250 ppm) and a high-Fe zone (average FeOt 12.5 wt% and Ni 1700 ppm). Both zones have high MgO (32-47 wt%) and varying Cr (830-5160 ppm) and Al2O3/TiO2 (16-26). Textural and geochemical layering is similar along the 30 km strike of the basal dunite. A LREE-enriched high-MgO basaltic parental magma composition (13-18 wt% MgO) is inferred for the basal dunite from olivine-melt mixing trends in orthocumulates. The dunite exhibits at least two geochemical reversals as well as abundant low-porosity adcumulates, poikilitic chromite, and bimodal olivine, suggesting formation in a high-volume open magmatic system. Significant similarity in major and trace element compositions with the Narankavaara layered series and the Burakovsky intrusion and Vetreny belt extrusives in Russian Karelia suggests that the basal dunite belongs to the Fennoscandian 2.5-2.4 Ga mafic layered intrusions. An Archean komatiitic origin for the dunite body cannot be completely ruled out, however. Distinct Ni-depletion in olivine is found in the basal dunite from the low-Fe zone to the high-Fe zone (3200 versus 2200 ppm). This depletion does not correlate with Fo contents, which suggests that it is not related to olivine fractionation. The basal dunite may thus have potential for Ni-(Cu-Co-PGE) sulfide mineralization.Peer reviewe

East Asia and the global/transatlantic/Western crisis

This paper introduces the special collection on East Asia and the Global Crisis. After justifying why a focus on East Asia is appropriate, it draws out the main themes that run through the individual contributions. These are the extent to which the region is decoupling from the global economy (or the West), the increasing legitimacy of statist alternatives to neoliberal development strategies, and the impact of crises on the definition of ―region‖ and the functioning of regional institutions and governance mechanisms

Influence of bird faeces in the behaviour of the root rot of Quercus suber caused by Phytophthora cinnamomi at Doñana Biological Reserve (SW Spain)

2 pages, 1 reference. Presentado a The Sixth Meeting of the IUFRO Working Party 7‐02‐09, celebrado en Córdoba (España) del 9-14 de septiembre de 2012. Enlazamos con http://hdl.handle.net/10261/57038; http://hdl.handle.net/10261/57047Centennial cork oaks are considered keystone structures in the ecosystem of the stabilised sands of the Doñana Biological Reserve. These remnant big trees are currently threatened by nesting of colonial waterbirds, whose debris induced deep soil chemical changes.Peer reviewe

Coupled surface-plasmon-like modes between metamaterial

Alastair P. Hibbins, Matthew J. Lockyear, and J. Roy Sambles, Physical Review B, Vol. 76, article 165431 (2007). "Copyright © 2007 by the American Physical Society."Perfectly conducting metals may be structured with holes to make metamaterials that support surface-plasmon-like modes at microwave frequencies. Results are presented for Fabry-Pérot-like standing wave resonances formed from coupled surface-plasmon-like modes supported by two such perforated metal substrates placed in close proximity

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