Effective-periodicity effects in Fibonacci slot arrays

In this Letter, the transmission properties of a nonperiodic array of slots arranged in the form of a Fibonacci sequence are investigated. By arranging the slots in this manner, an additional periodicity can be utilized, resulting in corresponding resonance features in the transmitted signal. By investigating the transmission response of a perforated metallic sheet over a broad frequency range (6–40 GHz), it is shown that this simple one-dimensional chain supports two periodicities, one due to the regular periodic separation and one due to average spacing—which is related to the golden ratio. This response replicates the resonant behavior of a two-dimensional periodic array with a single nonperiodic array also creating new families of diffraction lobes in the far-field region.MCIN/AEI/10.13039/501100011033 PID2020-116739GB-I00EPSRC EP/R004781/1EPSRC EP/L015331/

Empleo de las Componentes Principales en sus investigaciones biológicas. II.- Obtención de variables canónicas.

435 variables were analyzed in 4876 experimental units, from 23 experiments in the biological sciences, conducted in the period 1990-2004, which were significant to the Kaiser-Mayer –Olkin and Bartlet tests, with a view to assessing, when the Main Components technique, the methodology to be used in obtaining the canonical variables. The results obtained in the number of canonical variables per experiment, independent variables and cumulative variability (%) were 2.8 ± 0.08; 1.5 ± 0.51 and 61.1 ± 0.05 respectively. The behavior of the variables responses and the necessary Dollars to be carried out when I.- The Methodology is applied and II.- It does not apply, they left I = 19.0 and II = 4.3 ± 1.22 (p <0, 05) Variables Response and I = 66.8 and II = 14, 6 ± 4.89 (p <0.05) Dollars made. It is concluded that there is a significant decrease in the statistical tests with the canonical variables obtained (p <0.05), obtaining that in 17% of the experiments analyzed the transformed variables were not independent, being necessary to apply the proposed method again, which requires that the sphericity and Kaiser-Mayer-Olkin tests be carried out to guarantee the independence of the variables to be processed in decision making.Se analizaron 435 variables en 4876 unidades experimentales, procedentes de 23 experimentos en las ciencias biológicas, realizados en el período 1990-2004, que fueron significativos a las pruebas de Kaiser-Mayer –Olkin y Bartlet, con vistas a valorar , cuando se emplea la técnica de Componentes Principales, la metodología a utilizar en la obtención de las variables canónicas. Los resultados obtenidos en el número de variables canónicas por experimento, variables independientes y variabilidad acumulada (%) fueron 2,8 ± 0,08 ; 1,5 ± 0,51 y 61,1 ± 0,05 respectivamente. El comportamiento de las variables respuestas y las Dócimas necesarias a realizar cuando I.- Se Aplica la Metodología y II.- No se Aplica se fueron de I = 19,0 y II =4,3 ± 1,22 ( p< 0,05) Variables Respuesta y I=66,8 y II =14, 6 ± 4,89 (p < 0,05) Dócimas realizadas. Se concluye que se produce una disminución significativa en las pruebas estadísticas con las variables canónicas obtenidas ( p < 0,05 ), obteniéndose que en el 17% de los experimentos analizados las variables transformadas no fueron independientes siendo necesario aplicar nuevamente el método propuesto, lo que exige que las pruebas de esfericidad y Kaiser-Mayer-Olkin se efectúen para garantizar la independencia de las variables a procesar en la toma de decisiones

RAEA-Heliciculture: mechanism of conservation and rural development in Andalusia

The fast growth system is a snail rearing method with a high degree of technification. Actually, the experimental evaluation of the system is being developed by an Andalusian Network of Agrarian Research (RAEA-Heliciculture) on commercial farms. The aim of this study was to compare the fast growth and the intensive systems in juvenile Helix aspersa snails. The growth and the growth patterns are studied in 5 groups of 60 H. aspersa snails reared with both systems. The snails reared with the fast growth system reached a high weight (0.956 g) and a low variability (13%). The growth rate with the fast growth system showed the best fit to exponential model, while the growth rate with the intensive system showed good fit to logistic model.El sistema de pronto engorde es una especialización productiva en la fase de crecimiento y engorde de Helix aspersa con alto nivel de tecnificación. Actualmente se está desarrollando su evaluación experimental en granjas comerciales, a través de una Red Andaluza de Experimentación Agraria (RAEA-Helicicultura). Con el objetivo de comparar el sistema de pronto engorde frente al intensivo, se estudia el crecimiento y su modelización en 5 lotes de 60 caracoles H. aspersa criados con ambos sistemas durante la fase juvenil. Los resultados muestran que los caracoles del sistema de pronto engorde alcanzan el peso más alto con 0,956 g y la menor variabilidad (13%). El crecimiento con el pronto engorde se ajusta a un modelo exponencial, mientras que el sistema intensivo muestra mayor bondad en el ajuste con el modelo logístico

Malacological diversity in Andalusia. Renewable resource

The aim of this study is the evaluation of malacological diversity in Andalusian region. It has been observed high heterogeneity in relation to distribution patters of snails. Terrestrial edible snail populations are grouped in zones in relation to spatial distribution and specie. Zone I is located in Sierra Morena and shows a low density level of the most commonly edible species (O. lactea, H. aspersa, T. pisana and E. vermiculata). Zone II is extended throughout La Campiña and Vega del Guadalquivir. This zone is widely populated by snails with great economically importance: O. lactea and T. pisana and H. aspersa with a smaller density. Zone III is located in Sierras Béticas and it is characterised by the presence of many endemic populations (O. lactea murcica, O. punctata, T. pisana arietina, T. subdentata helicella, C. nemoralis, I. gualtierianus gualtierianus, I. gualtierianus alonensis, I. gualtierianus guiraoanus, etc.). It is necessary to develop strategic plans in order to conserve the malacological diversity in Andalusia.El objetivo del estudio es la evaluación de la diversidad malacológica andaluza como base del aprovechamiento de un recurso genético de interés económico. Se zonifican las poblaciones de caracoles comestibles existentes en Andalucía en relación al número de especies y su distribución geográfica. Se observa elevada heterogeneidad que da lugar a la conformación de tres zonas diferenciadas, en las que aparecen fundamentalmente los géneros Otala, Theba, Cantareus, Iberus, Eobania, Cepaea, Pseudotachea y Sphincterochila. La Zona I comprende Sierra Morena y se caracteriza por una baja presencia de caracoles, asociados mayoritariamente a la presencia humana y representados por las especies más comunes (O. lactea, H. aspersa, T. pisana y E. vermiculata). La Zona II comprende la Campiña y Vega del Guadalquivir, donde aparecen las especies de mayor valor comercial: O. lactea y T. pisana, con gran distribución; y H. aspersa con menor presencia. Finalmente la Zona III, que se integra por las Sierras Béticas donde aparecen, junto con las especies anteriormente citadas, gran diversidad de taxones con elevada singularidad, debido a la existencia de un número importante de endemismos y poblaciones relictas (O. lactea murcica, O. punctata, T. pisana arietina, T. subdentata helicella, C. nemoralis, I. gualtierianus gualtierianus, I. gualtierianus alonensis, I. gualtierianus guiraoanus, etc.). La existencia de esta biodiversidad justifica la necesidad de adoptar acciones estratégicas y planes específicos de conservación que preserven este recurso de forma eficaz

Elevated Plasma Endothelin-1 and Pulmonary Arterial Pressure in Children Exposed to Air Pollution

BackgroundControlled exposures of animals and humans to particulate matter (PM) or ozone air pollution cause an increase in plasma levels of endothelin-1, a potent vasoconstrictor that regulates pulmonary arterial pressure.ObjectivesThe primary objective of this field study was to determine whether Mexico City children, who are chronically exposed to levels of PM and O3 that exceed the United States air quality standards, have elevated plasma endothelin-1 levels and pulmonary arterial pressures.MethodsWe conducted a study of 81 children, 7.9 ± 1.3 years of age, lifelong residents of either northeast (n = 19) or southwest (n = 40) Mexico City or Polotitlán (n = 22), a control city with PM and O3 levels below the U.S. air quality standards. Clinical histories, physical examinations, and complete blood counts were done. Plasma endothelin-1 concentrations were determined by immunoassay, and pulmonary arterial pressures were measured by Doppler echocardiography.ResultsMexico City children had higher plasma endothelin-1 concentrations compared with controls (p < 0.001). Mean pulmonary arterial pressure was elevated in children from both northeast (p < 0.001) and southwest (p < 0.05) Mexico City compared with controls. Endothelin-1 levels in Mexico City children were positively correlated with daily outdoor hours (p = 0.012), and 7-day cumulative levels of PM air pollution < 2.5 μm in aerodynamic diameter (PM2.5) before endothelin-1 measurement (p = 0.03).ConclusionsChronic exposure of children to PM2.5 is associated with increased levels of circulating endothelin-1 and elevated mean pulmonary arterial pressure

Cardiovascular-related proteomic changes in ECFCs exposed to the serum of COVID-19 patients

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection significantly affects the cardiovascular system, causing vascular damage and thromboembolic events in critical patients. Endothelial dysfunction represents one of the first steps in response to COVID-19 that might lead to cardiovascular complications and long-term sequelae. However, despite the enormous efforts in the last two years, the molecular mechanisms involved in such processes remain poorly understood. Herein, we analyzed the protein changes taking place in endothelial colony forming cells (ECFCs) after the incubation with the serum from individuals infected with COVID-19, whether asymptomatic or critical patients, by application of a label free-quantitative proteomics approach. Specifically, ECFCs from healthy individuals were incubated ex-vivo with the serum of either COVID-19 negative donors (PCR-/IgG-, n:8), COVID-19 asymptomatic donors at different infective stages (PCR+/ IgG-, n:8and PCR-/IgG+, n:8), or hospitalized critical COVID-19 patients (n:8), followed by proteomics analysis. In total, 590 proteins were differentially expressed in ECFCs in response to all infected serums. Predictive analysis highlighted several proteins like CAPN5, SURF4, LAMP2 or MT-ND1, as highly discriminating features between the groups compared. Protein changes correlated with viral infection, RNA metabolism or autophagy, among others. Remarkably, the angiogenic potential of ECFCs in response to the infected serums was impaired, and many of the protein alterations in response to the serum of critical patients were associated with cardiovascular-related pathologies.This study was supported by GLOBALCAJA-Ayuda COVID-19; and Fondo Supera COVID-19, funded by Banco Santander and CRUE universidades, Ref. IPSA-COVID-19, and the Institute of Health Carlos III, ISCIII (PI18-00427, PI20-00716), co-funded by European Regional Development “A way to make Europe”

Near barrier scattering of 8He on 208Pb

The exotic nucleus 8He is investigated by means of the measurement of the angular distributions of the elastic channel and the 6He and 4He fragment yields produced in the collision with a 208Pb target at two energies around the Coulomb barrier, 16 and 22 MeV. The experiment was performed at the GANIL-SPIRAL facility, with the aim of extracting information about the structure of 8He and the relevant reaction mechanisms. In this contribution, details of the experimental setup and preliminary data on elastic cross sections are reported

Diet of two syntopic species of Crenuchidae (Ostariophysi: Characiformes) in an Amazonian rocky stream

Abstract This study assessed the diet of two poorly known syntopic fish species of the family Crenuchidae, Characidium aff. declivirostre and Leptocharacidium omospilus, in a Presidente Figueiredo´ rocky stream, Amazonas, Brazil. The stomach contents were analyzed and their Frequency of Occurrence (FO %) and Relative Volume (Vol %) were combined in a Feeding Index (IAi). We examined 20 individuals of C. aff. declivirostre and 23 of L. omospilus. The Morisita-Horn Index was used to estimate the overlap between the diets of these species. Immature insects were the most valuable items consumed by both fish species. The diet of C. aff. declivirostre was mainly composed of larvae and pupae of Chironomidae, while L. omospilus predominantly consumed larvae of Hydroptilidae, Hydropyschidae and Pyralidae. Thus, both species were classified as autochthonous insectivorous. Characidium aff. declivirostre was considered a more specialized species, probably reflecting lower feeding plasticity or the use of more restricted microhabitats compared to L. omospilus. When the food items were analyzed at the family taxonomic level, the diet overlap between these species was considered moderate (Morisita-Horn Index = 0.4). However, a more thorough analysis, at the genus level, indicates a very low diet overlap. Therefore, we conclude that the feeding segregation between C. aff. declivirostre and L. omospilus may favor their co-existence, despite their high phylogenetic closeness