Neurological complications of acute multifocal placoid pigment epitheliopathy

Acute multifocal placoid pigment epitheliopathy (AMPPE) is an autoimmune chorioretinal disease that can be complicated by neurological involvement. There is limited information on this potentially treatable condition in the neurological literature. The objective of this patient series is to describe the neurological complications of AMPPE. We retrospectively identified patients with neurological complications of AMPPE seen at Auckland Hospital between 2008 and 2013 and summarised cases in the literature between 1976 and 2013. We identified five patients with neurological complications of AMPPE at Auckland Hospital and 47 reported patients. These patients demonstrated a spectrum of neurological involvement including isolated headache, stroke or transient ischaemic attack, seizures, venous sinus thrombosis, optic neuritis, sensorineural hearing loss and peripheral vestibular disorder. We propose criteria to define AMPPE with neurological complications. A cerebrospinal fluid (CSF) lymphocytosis in a patient with isolated headache may predict the development of cerebrovascular complications of AMPPE. Patients with cerebrovascular complications of AMPPE have a poor prognosis with high rates of death and neurological disability among survivors. Predictors of poor outcome in those who develop neurological complications of AMPPE are a relapsing course, generalised seizures and multifocal infarction on MRI. All patients with neurological complications of AMPPE, including headache alone, should be investigated with an MRI brain and CSF examination. Patients with focal neurological symptoms should receive intravenous (IV) methylprednisolone followed by a tapering course of oral steroids for at least 3months. Patients with AMPPE and an isolated headache with a CSF pleocytosis should be treated with oral steroids

Magneto-optical trap for metastable helium at 389 nm

We have constructed a magneto-optical trap (MOT) for metastable triplet helium atoms utilizing the 2 3S1 -> 3 3P2 line at 389 nm as the trapping and cooling transition. The far-red-detuned MOT (detuning Delta = -41 MHz) typically contains few times 10^7 atoms at a relatively high (~10^9 cm^-3) density, which is a consequence of the large momentum transfer per photon at 389 nm and a small two-body loss rate coefficient (2 * 10^-10 cm^3/s < beta < 1.0 * 10^-9 cm^3/s). The two-body loss rate is more than five times smaller than in a MOT on the commonly used 2 3S1 -> 2 3P2 line at 1083 nm. Furthermore, we measure a temperature of 0.46(1) mK, a factor 2.5 lower as compared to the 1083 nm case. Decreasing the detuning to Delta= -9 MHz results in a cloud temperature as low as 0.25(1) mK, at small number of trapped atoms. The 389 nm MOT exhibits small losses due to two-photon ionization, which have been investigated as well.Comment: 11 page

Acid Decomposition Of Yerba Mate (ilex Paraguariensis) Using A Reflux System For The Evaluation Of Al, Ca, Cd, Cr, Cu, Fe, K, Mg, Mn, Na, Pb And Zn Contents By Atomic Spectrometric Techniques

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)In the first part of this paper, two acid decomposition procedures for the determination of Al, Ca, Fe, Mg, Mn and Zn contents in yerba mate samples by inductively coupled plasma optical emission spectrometry (ICP OES) were compared. Using a reflux system, the samples were treated with a mixture of HNO3 and H2O2 for 3 hours at 220 degrees C in the digester block. The results from five commercial yerba mate samples were compared with the results obtained from microwave digestion. Good agreement between the procedures at a 95% confidence level was obtained with relative standard deviation (RSD) values lower than 10.0%. The accuracy was evaluated using addition and recovery experiments (80.5 to 112.8%). In the second part, Ca, Cd, Cr, Cu, Fe, K, Mg, Na, Pb and Zn concentrations were evaluated in the yerba mate infusion. The results showed that elements such as Na, K, Mg and Zn are easily transferred to the hot water used for the infusion. For Pb and Cd, the concentrations found in the analyzed samples were lower than the values established by Brazilian legislation.274685693Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq)Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES) [552197/2011-4]Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

Analysis of Finite Microstrip Structures Using an Efficient Implementation of the Integral Equation Technique

An efficient numerical implementation of the Integral Equation technique (IE) has been developed for the analysis of the electrical characteristics of finite microstrip structures. The technique formulates a volume version of the IE for the finite dielectric objects, and a standard surface IE technique for the metallic areas. The system of integral equations formu- lated are solved with special numerical techniques described in this paper. The input impedances of several microstrip antennas have been computed, showing good agreement with respect mea- surements. The technique has shown to be accurate even for complex geometries containing several stacked dielectric layers. The radiation patterns of the structures have also been com- puted, and measured results from real manufactured hardware confirm that backside radiation and secondary lobes are accurately predicted by the theoretical model. The paper also discuss a suitable excitation model for finite size ground planes, and investigates the possibilities for an independent meshing of the metallic areas and the dielectric objects inside a given geom- etry. The practical value of the approach derived is that microstrip circuits can be designed minimizing the volume and size of the dielectric substrates.This work has been supported bythe Spanish National Project ESP2001-4546-PE, and RegionalSeneca Project PB/4/FS/02

Adatoms in Graphene

We review the problem of adatoms in graphene under two complementary points of view, scattering theory and strong correlations. We show that in both cases impurity atoms on the graphene surface present effects that are absent in the physics of impurities in ordinary metals. We discuss how to observe these unusual effects with standard experimental probes such as scanning tunneling microscopes, and spin susceptibility.Comment: For the Proceedings of the "Graphene Week 2008" at the ICTP in Trieste, Italy. 8 pages, 8 figure

Efficient magneto-optical trapping of a metastable helium gas

This article presents a new experiment aiming at BEC of metastable helium atoms. It describes the design of a high flux discharge source of atoms and a robust laser system using a DBR diode coupled with a high power Yb doped fiber amplifier for manipulating the beam of metastable atoms. The atoms are trapped in a small quartz cell in an extreme high vacuum. The trapping design uses an additional laser (repumper) and allows the capture of a large number of metastable helium atoms (approximately $10^9$) in a geometry favorable for loading a tight magnetostatic trap.Comment: 12 pages, 7 figures, Late

Non-destructive, dynamic detectors for Bose-Einstein condensates

We propose and analyze a series of non-destructive, dynamic detectors for Bose-Einstein condensates based on photo-detectors operating at the shot noise limit. These detectors are compatible with real time feedback to the condensate. The signal to noise ratio of different detection schemes are compared subject to the constraint of minimal heating due to photon absorption and spontaneous emission. This constraint leads to different optimal operating points for interference-based schemes. We find the somewhat counter-intuitive result that without the presence of a cavity, interferometry causes as much destruction as absorption for optically thin clouds. For optically thick clouds, cavity-free interferometry is superior to absorption, but it still cannot be made arbitrarily non-destructive . We propose a cavity-based measurement of atomic density which can in principle be made arbitrarily non-destructive for a given signal to noise ratio

Expansion of a Bose-Einstein Condensate in an atomic waveguide

The expansion of a Bose-Einstein condensate in an atomic waveguide is analyzed. We study different regimes of expansion, and identify a transient regime between one-dimensional and three-dimensional dynamics, in which the properties of the condensate and its further expansion can be well explained by reducing the transversal dynamics to a two-level system. The relevance of this regime in current experiments is discussed.Comment: 4 pages, 3 figs, Accepted for publication in Phys. Rev.

Acid decomposition of yerba mate (ilex paraguariensis) using a reflux system for the evaluation of Al, Ca, Cd, Cr, Cu, Fe, K, Mg, Mn, Na, Pb and Zn contents by atomic spectrometric techniques

In the first part of this paper, two acid decomposition procedures for the determination of Al, Ca, Fe, Mg, Mn and Zn contents in yerba mate samples by inductively coupled plasma optical emission spectrometry (ICP OES) were compared. Using a reflux system, the samples were treated with a mixture of HNO3 and H2O2 for 3 hours at 220 °C in the digester block. The results from five commercial yerba mate samples were compared with the results obtained from microwave digestion. Good agreement between the procedures at a 95% confidence level was obtained with relative standard deviation (RSD) values lower than 10.0%. The accuracy was evaluated using addition and recovery experiments (80.5 to 112.8%). In the second part, Ca, Cd, Cr, Cu, Fe, K, Mg, Na, Pb and Zn concentrations were evaluated in the yerba mate infusion. The results showed that elements such as Na, K, Mg and Zn are easily transferred to the hot water used for the infusion. For Pb and Cd, the concentrations found in the analyzed samples were lower than the values established by Brazilian legislation274685693CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DO RIO GRANDE DO SUL - FAPERGSSem informação552197/2011-4Sem informaçã

Dietary iron depletion at weaning imprints low microbiome diversity and this is not recovered with oral nano Fe(III)

Alterations in the gut microbiota have been recently linked to oral iron. We conducted two feeding studies including an initial diet-induced iron-depletion period followed by supplementation with nanoparticulate tartrate-modified ferrihydrite (Nano Fe(III): considered bioavailable to host but not bacteria) or soluble ferrous sulfate (FeSO4: considered bioavailable to both host and bacteria). We applied denaturing gradient gel electrophoresis and fluorescence in situ hybridization for study-1 and 454-pyrosequencing of fecal 16S rRNA in study-2. In study-1, the within-community microbial diversity increased with FeSO4 (P = 0.0009) but not with Nano Fe(III) supplementation. This was confirmed in study-2, where we also showed that iron depletion at weaning imprinted significantly lower within- and between-community microbial diversity compared to mice weaned onto the iron-sufficient reference diet (P < 0.0001). Subsequent supplementation with FeSO4 partially restored the within-community diversity (P = 0.006 in relation to the continuously iron-depleted group) but not the between-community diversity, whereas Nano Fe(III) had no effect. We conclude that (1) dietary iron depletion at weaning imprints low diversity in the microbiota that is not, subsequently, easily recovered; (2) in the absence of gastrointestinal disease iron supplementation does not negatively impact the microbiota; and (3) Nano Fe(III) is less available to the gut microbiota