Non-Hermitian robust edge states in one-dimension: Anomalous localization and eigenspace condensation at exceptional points

Capital to topological insulators, the bulk-boundary correspondence ties a topological invariant computed from the bulk (extended) states with those at the boundary, which are hence robust to disorder. Here we put forward an ordering unique to non-Hermitian lattices, whereby a pristine system becomes devoid of extended states, a property which turns out to be robust to disorder. This is enabled by a peculiar type of non-Hermitian degeneracy where a macroscopic fraction of the states coalesce at a single point with geometrical multiplicity of $1$, that we call a phenomenal point.Comment: 6 pages, 4 figure

Patch Antenna Based on Metamaterials for a RFID Transponder

In this paper a self-diplexed antenna is proposed for a RFID transponder application. The development cycle is divided into two stages: antenna design and filters design. The antenna is based on a square microstrip patch filled with metamaterial structures. The inclusion of these structures allows simultaneous operation over several frequencies, which can be arbitrarily chosen. The antenna working frequencies are chosen to be 2.45 GHz (receiver) and 1.45 GHz (transmitter). In addition, the antenna is fed through two orthogonal coupled microstrip lines, what provides higher isolation between both ports. Some filters based on metamaterial particles are coupled or connected to the antenna feeding microstrip lines to avoid undesired interferences. This approach avoids using of an external filter or diplexer, providing larger size reduction and a compact self-diplexed antenna

A SCN9A gene-encoded dorsal root ganglia sodium channel polymorphism associated with severe fibromyalgia

<p>Abstract</p> <p>Background</p> <p>A consistent line of investigation suggests that autonomic nervous system dysfunction may explain the multi-system features of fibromyalgia (FM); and that FM is a sympathetically maintained neuropathic pain syndrome. Dorsal root ganglia (DRG) are key sympathetic-nociceptive short-circuit sites. Sodium channels located in DRG (particularly Nav1.7) act as molecular gatekeepers for pain detection. Nav1.7 is encoded in gene SCN9A of chromosome 2q24.3 and is predominantly expressed in the DRG pain-sensing neurons and sympathetic ganglia neurons. Several SCN9A sodium channelopathies have been recognized as the cause of rare painful dysautonomic syndromes such as paroxysmal extreme pain disorder and primary erythromelalgia. The aim of this study was to search for an association between fibromyalgia and several SCN9A sodium channels gene polymorphisms.</p> <p>Methods</p> <p>We studied 73 Mexican women suffering from FM and 48 age-matched women who considered themselves healthy. All participants filled out the Fibromyalgia Impact Questionnaire (FIQ). Genomic DNA from whole blood containing EDTA was extracted by standard techniques. The following SCN9A single-nucleotide polymorphisms (SNP) were determined by 5' exonuclease TaqMan assays: rs4371369; rs4387806; rs4453709; rs4597545; rs6746030; rs6754031; rs7607967; rs12620053; rs12994338; and rs13017637.</p> <p>Results</p> <p>The frequency of the rs6754031 polymorphism was significantly different in both groups (<it>P </it>= 0.036) mostly due to an absence of the GG genotype in controls. Interestingly; patients with this rs6754031 GG genotype had higher FIQ scores (median = 80; percentile 25/75 = 69/88) than patients with the GT genotype (median = 63; percentile 25/75 = 58/73; <it>P </it>= 0.002) and the TT genotype (median = 71; percentile 25/75 = 64/77; <it>P </it>= 0.001).</p> <p>Conclusion</p> <p>In this ethnic group; a disabling form of FM is associated to a particular SCN9A sodium channel gene variant. These preliminary results raise the possibility that some patients with severe FM may have a dorsal root ganglia sodium channelopathy.</p

The effect of interpolation methods in temperature and salinity trends in the Western Mediterranean

Temperature and salinity data in the historical record are scarce and unevenly distributed in space and time and the estimation of linear trends is sensitive to different factors. In the case of the Western Mediterranean, previous works have studied the sensitivity of these trends to the use of bathythermograph data, the averaging methods or the way in which gaps in time series are dealt with. In this work, a new factor is analysed: the effect of data interpolation. Temperature and salinity time series are generated averaging existing data over certain geographical areas and also by means of interpolation. Linear trends from both types of time series are compared. There are some differences between both estimations for some layers and geographical areas, while in other cases the results are consistent. Those results which do not depend on the use of interpolated or non-interpolated data, neither are influenced by data analysis methods can be considered as robust ones. Those results influenced by the interpolation process or the factors analysed in previous sensitivity tests are not considered as robust results

Topological states of non-Hermitian systems

Recently, the search for topological states of matter has turned to non-Hermitian systems, which exhibit a rich variety of unique properties without Hermitian counterparts. Lattices modeled through non-Hermitian Hamiltonians appear in the context of photonic systems, where one needs to account for gain and loss, circuits of resonators, and also when modeling the lifetime due to interactions in condensed matter systems. Here we provide a brief overview of this rapidly growing subject, the search for topological states and a bulk-boundary correspondence in non-Hermitian systems.Comment: Invited short review for the special issue "Topological States of Matter: Theory and Applications

Volúmenes molares aparentes de los anestésicos procaína-HCl y lidocaína-HCl en agua a temperaturas entre 278,15 y 313,15 K

La lidocaína-HCl y procaína-HCl son anestésicos locales ampliamente usados en procedimientos quirúrgicos menores, sin embargo la información fisicoquímica acerca de su comportamiento volumétrico, así como de otras propiedades fisicoquímicas, aún es incompleta en la actualidad. Por esta razón, en este artículo se presentan los valores de densidad de algunas soluciones acuosas de estos dos fármacos en función de la concentración (desde 0,0500 hasta 0,5000) mol kg–1 a diferentes temperaturas (278,15, 283,15, 288,15, 293,15, 298,15, 303,15, 308,15 y 313,15 K). Así mismo se presentan los volúmenes molares aparentes y volúmenes molares parciales a dilución infinita de los fármacos como electrolitos, y de otro lado, los volúmenes molares parciales a dilución infinita de los fármacos moleculares y las expansibilidades molares, los cuales fueron calculados a partir de los valores de densidad y composición de las mezclas. Los resultados obtenidos se interpretan en términos de interacciones soluto-solvente.Lidocaine-HCl and procaine-HCl are local anesthetic drugs widely used in minor chirurgic procedures, nevertheless, physicochemical information about their volumetric behavior, as well as for other aqueous properties, is not complete at present. In this context, in this article, densities of aqueous solutions of both drugs have been measured as a function of concentration (from 0.0500 to 0.5000) mol kg–1 at several temperatures, i.e. 278.15, 283.15, 288.15, 293.15, 298.15, 303.15, 308.15, and 313.15 K. The apparent molar volumes and partial molar volumes at infinite dilution for the electrolyte drugs were calculated, whereas, the partial molar volumes at infinite dilution and partial molar expansibilities for the molecular forms were also calculated. The dependence of these properties with temperature is shown. The results are interpreted in terms of interaction solute-solvent.Fil: Delgado, Daniel R.. Universidad Nacional de Colombia; ColombiaFil: Jimenez Kairuz, Alvaro Federico. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Farmacia; ArgentinaFil: Manzo, Ruben Hilario. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Farmacia; ArgentinaFil: Vargas, Edgar F.. Universidad de los Andes; ColombiaFil: Martinez, Fleming. Universidad Nacional de Colombia; Colombi

Necrotizing entercolitis: socio-demographic, clinical and histopathological findings in a series of neonatal autopsies

La enterocolitis necrotizante es un trastorno caracterizado por la necrosis isquémica de la mucosa intestinal, es la enfermedad gastrointestinal más grave que afecta a los neonatos, con alta morbilidad y mortalidad, principalmente en prematuros. El objetivo del presente estudio es describir las características clínicas y anatomopatológicas de los recién nacidos fallecidos con enterocolitis necrotizante, diagnosticados en un hospital de alta complejidad. Metodología. Este es un estudio descriptivo retrospectivo de 21 casos de autopsias médico-científicas hechas en un hospital de alta complejidad del nororiente colombiano, con hallazgos anatomopatológicos de enterocolitis necrotizante, realizadas entre enero de 2013 y julio de 2017. Resultados. El 85.7% de los recién nacidos eran pretérminos, un igual porcentaje presentaba un peso menor a 2,500 gramos al nacer. Respecto a los antecedentes maternos el 14.3% tuvieron espectro de trastornos hipertensivos asociados al embarazo y el 23.8% infección materna. Los tres sitios más frecuentes de ubicación de enterocolitis necrotizantes fue íleon, colon ascendente y colon transverso. Discusión. Según algunos autores, hasta el 85% de todos los casos de enterocolitis necrotizante ocurren en pacientes prematuros, especialmente en bebés con peso extremadamente bajo al nacer. Hay formas de enterocolitis necrotizante que ocurren en bebés a término y, generalmente, están asociadas con factores predisponentes, resultados compatibles con lo que encontramos en esta investigación. Conclusiones. Este estudio elaborado con población colombiana se correlaciona con lo descrito en la población mundial en la cual la enterocolitis necrotizante se presenta más en los recién nacidos pretérmino y con bajo peso al nacer.Necrotizing entercolitis is a disorder characterized by the ischemic necrosis of intestinal mucosa. It is the most serious gastrointestinal disease affecting neonates, with high morbidity and mortality rates, mainly among premature newborns. The purpose of this study is to describe the clinical and anatamo-pathological characteristics of deceased newborns with necrotizing entercolitis, diagnosed at a high-complexity hospital. Methodology. This is a descriptive retrospective study of 21 cases of medical-scientific autopsies performed at a high-complexity hospital in northeastern Colombia, with anatomo-pathological findings of necrotizing entercolitis, performed between January 2013 and July 2017. Results. 85.7% of the newborns were pre-term, and the same percentage had weight at birth below 2.5 kilograms. Regarding the mothers’ background, 14.3% displayed a spectrum of hypertensive disorders associated with pregnancy, and 23.8% had maternal infections. The three most frequent locations of necrotizing entercolitis were the ileum, ascending colon and transverse colon. Discussion. According to some authors, up to 85% of all cases of necrotizing entercolitis occur in premature patients, especially in babies with extremely low weight at birth. There are forms of necrotizing entercolitis that occur in full term babies, and they are generally associated with contributing factors, which is consistent with the findings of this study. Conclusions. This study of a Colombian population is consistent with other descriptions of the global population, where necrotizing entercolitis arises more frequently in pre-term newborns and low weight at birth

Risk of Invasive Fungal Infections in Patients with Chronic Lymphocytic Leukemia treated with Bruton Tyrosine Kinase Inhibitors – A Case-Control Propensity Score Matched Analysis

Background: Prior reports have suggested a possible increase in the frequency of invasive fungal infections (IFIs) with use of a Bruton tyrosine kinase inhibitors (BTKi) for treatment of chronic lymphoid malignancies such as chronic lymphocytic leukemia (CLL), but precise estimates are lacking. We aim to characterize the prevalence of IFIs among patients with CLL, for whom BTKi are now the first line recommended therapy. Methods: We queried TriNetX, a global research network database, to identify adult patients with CLL using the ICD-10 codes (C91.1) and laboratory results. We performed a case-control propensity score-matched analysis to determine IFIs events by BTKi use. We adjusted for age, sex, ethnicity, and clinical risk factors associated with an increased risk of IFIs. Results: Among 5,358 matched patients with CLL, we found an incidence of 4.6% of IFIs in patients on a BTKi vs. 3.5% among patients with CLL not on a BTKi at five years. Approximately 1% of patients with CLL developed an IFI while on a BTKi within this period. Our adjusted IFI event analysis found an elevated rate of Pneumocytis jirovecii pneumonia (PJP) (0.5% vs. 0.3%, p = 0.02) and invasive candidiasis (3.5% vs 2.7%, p = 0.012) with the use of a BTKi. The number needed to harm for patients taking a BTKi was 120 and 358 for invasive candidiasis and PJP, respectively. Conclusions: We found an adjusted elevated rate of PJP and invasive candidiasis with BTKi use. The rates are however low with a high number needed to harm. Additional studies stratifying other IFIs with specific BTKi are required to identify at-risk patients and preventive, cost-effective interventions

Concerted changes in tropical forest structure and dynamics: evidence from 50 South American long-term plots

Several widespread changes in the ecology of old-growth tropical forests have recently been documented for the late twentieth century, in particular an increase in stem turnover (pan-tropical), and an increase in above-ground biomass (neotropical). Whether these changes are synchronous and whether changes in growth are also occurring is not known. We analysed stand-level changes within 50 long-term. monitoring plots from across South America spanning 1971-2002. We show that: (i) basal area (BA: sum of the cross-sectional areas of all trees in a plot) increased significantly over time (by 0.10 +/- 0.04 m(2) ha(-1) yr(-1), mean +/- 95% CI); as did both (ii) stand-level BA growth rates (sum of the increments of BA of surviving trees and BA of new trees that recruited into a plot); and (iii) stand-level BA mortality rates (sum of the cross-sectional areas of all trees that died in a plot). Similar patterns were observed on a per-stem basis: (i) stem density (number of stems per hectare; 1 hectare is 10(4) m(2)) increased significantly over time (0.94 +/- 0.63 stems ha(-1) yr(-1)); as did both (ii) stem recruitment rates; and (iii) stem mortality rates. In relative terms, the pools of BA and stem density increased by 0.38 +/- 0.15% and 0.18 +/- 0.12% yr(-1), respectively. The fluxes into and out of these pools-stand-level BA growth, stand-level BA mortality, stem recruitment and stem mortality rates-increased, in relative terms, by an order of magnitude more. The gain terms (BA growth, stem recruitment) consistently exceeded the loss terms (BA loss, stem mortality) throughout the period, suggesting that whatever process is driving these changes was already acting before the plot network was established. Large long-term increases in stand-level BA growth and simultaneous increases in stand BA and stem density imply a continent-wide increase in resource availability which is increasing net primary productivity and altering forest dynamics. Continent-wide changes in incoming solar radiation, and increases in atmospheric concentrations of CO2 and air temperatures may have increased resource supply over recent decades, thus causing accelerated growth and increased dynamism across the world's largest tract of tropical forest