Computing the Casimir energy using the point-matching method

We use a point-matching approach to numerically compute the Casimir interaction energy for a two perfect-conductor waveguide of arbitrary section. We present the method and describe the procedure used to obtain the numerical results. At first, our technique is tested for geometries with known solutions, such as concentric and eccentric cylinders. Then, we apply the point-matching technique to compute the Casimir interaction energy for new geometries such as concentric corrugated cylinders and cylinders inside conductors with focal lines.Comment: 11 pages, 18 figure

Decomposition and biological colonization of native and exotic leaf litter in a Central Spain stream

Riparian invasion by exotic trees may lead to changes in the quality of leaf-litter inputs to freshwater ecosystems. Leaflitter inputs are especially important in headwater streams, where aquatic food webs largely depend on the organic matter provided by the terrestrial vegetation. In a headwater stream of Central Spain, North of Guadalajara Province (Tagus basin) we compared the decomposition and biological colonization of leaf litter among two exotic (Ailanthus altissima Mill. Swingle and Robinia pseudoacacia L.) and two native trees (Fraxinus angustifolia Vahl. and Populus alba L.) co-existing in riparian zones. We hypothesized a lower biological colonization of exotic leaves due to organisms have not co-evolved with the exotic trees according to the Novel Weapons Hypothesis (NWH) and, consequently, lower decomposition rates of exotic leaves. To test our hypothesis, litter bags with different mesh sizes (coarse (C) and fine (F)), were used to distinguish between the total and microbial decomposition. The litter bags were placed in the stream and recovered after 2, 20, 39, 62 and 82 days of incubation. After each collection, we assessed the amount of remaining litter, analysed the nitrogen (N) and phosphorous (P) in the litter, identified the macroinvertebrates and quantified the fungal biomass. Consistent with our hypothesis, we found greater fungal biomass buildup on native leaves than on exotic leaves. However, decomposition rates (k) were species-specific, being the ranking in C-bags (A. altissima = F. angustifolia > P. alba > R. pseudoacacia) slightly different than in F-bags (A. altissima > F. angustifolia > P. alba > R. pseudoacacia). The k in both the C-bags and F-bags were correlated with leaf traits, such as lignin, acid detergent fibre (ADF) and lignin:P. There was not a clear effect of the exotic species on macroinvertebrate variables, but the contribution of macroinvertebrates to litter decomposition was lower in exotic litter than in native litter, as shown by a lower ratio between k in C-bags and k in F-bags (kC : kF). Our results supported that invasive species might impact both biological colonization and decomposition rates in stream ecosystems by the addition of different quality leaf litter when compared to native vegetation. The differences in the biological colonization may be explained by the NWH, but differences in the decomposition rates were better explained by litter quality

Decomposition and biological colonization of native and exotic leaf litter in a stream

Riparian invasion by exotic trees may lead to changes in the quality of leaf-litter inputs to freshwater ecosystems. Leaflitterinputs are especially important in headwater streams, where aquatic food webs largely depend on the organic matterprovided by the terrestrial vegetation. In a headwater stream of Central Spain, North of Guadalajara Province (Tagus basin)we compared the decomposition and biological colonization of leaf litter among two exotic (Ailanthus altissima Mill. Swingleand Robinia pseudoacacia L.) and two native trees (Fraxinus angustifolia Vahl. and Populus alba L.) co-existing in riparianzones.We hypothesized a lower biological colonization of exotic leaves due to organisms have not co-evolved with the exotictrees according to the Novel Weapons Hypothesis (NWH) and, consequently, lower decomposition rates of exotic leaves. Totest our hypothesis, litter bags with different mesh sizes (coarse (C) and fine (F)), were used to distinguish between the totaland microbial decomposition. The litter bags were placed in the stream and recovered after 2, 20, 39, 62 and 82 days ofincubation. After each collection, we assessed the amount of remaining litter, analysed the nitrogen (N) and phosphorous(P) in the litter, identified the macroinvertebrates and quantified the fungal biomass. Consistent with our hypothesis, we foundgreater fungal biomass buildup on native leaves than on exotic leaves. However, decomposition rates (k) were species-specific,being the ranking in C-bags (A. altissima = F. angustifolia > P. alba > R. pseudoacacia) slightly different than in F-bags (A.altissima > F. angustifolia > P. alba > R. pseudoacacia).La invasión de las riberas por árboles exóticos puede provocar cambios en la calidad de las entradas de hojarasca a los ecosistemas de agua dulce, especialmente importantes en arroyos de cabecera, donde las redes tróficas dependen en gran medida de los aportes de materia orgánica proporcionada por la vegetación terrestre. En un arroyo de cabecera del Centro de España, Norte de la provincia de Guadalajara (Cuenca del Tajo), comparamos entre la descomposición y colonización biológica de la hojarasca de dos árboles exóticos (Ailanthus altissima Mill. Swingle y Robinia pseudoacacia L.) y dos nativos (Fraxinus angustifolia Vahl. y Populus alba L.), que coexisten en zonas de ribera. Hipotetizamos que habrá una menor colonización biológica de las hojas exóticas debido a que los organismos del arroyo no han co-evolucionado con los árboles exóticos de acuerdo con la Hipótesis de las Nuevas Armas (NWH) y, por tanto, menores tasas de descomposición de éstas. Para testar nuestra hipótesis, se sumergieron en el arroyo bolsas de descomposición con distinta de luz de malla, gruesa (C) y fina (F) –usadas para distinguir entre descomposición total y microbiana– y se recuperaron después de 2, 20, 39, 62 y 82 días de incubación. Después de la recolección pesamos la cantidad de hojarasca remanente, analizamos el nitrógeno (N) y fósforo (P) de la hojarasca, identificamos los macroinvertebrados y cuantificamos la biomasa fúngica. De acuerdo con nuestra hipótesis, encontramos mayor biomasa fúngica acumulada en hojas nativas que en exóticas. Sin embargo, la tasa de descomposición (k) fue específica de la especie, siendo el ranking en las bolsas C (A. altissima = F. angustifolia > P. alba > R. pseudoacacia) ligeramente diferente al de las bolsas F (A. altissima > F. angustifolia > P. alba > R. pseudoacacia). Ambas k (en bolsas C y F) se correlacionaron con lignina, fibra ácido detergente (ADF) y lignina:P. No hubo un efecto claro de las especies exóticas sobre las variables de macroinvertebrados, pero la contribución de los macroinvertebrados a la descomposición fue menor en la hojarasca exótica que en la nativa, como muestra el menor ratio entre k en bolsas C y F (kC : kF). Nuestros resultados apoyan que las especies invasoras pueden impactar tanto la colonización biológica como las tasas de descomposición de la hojarasca en los ecosistemas de arroyos mediante el aporte de hojarasca de distinta calidad respecto de la vegetación nativa. Las diferencias en colonización biológica pueden ser explicadas por la NHW pero las diferencias en descomposición son mejor explicadas por la calidad de la hojarasca.Ministerio de Economía y CompetitividadJunta de Comunidades de Castilla-La ManchaComunidad de Madri

Integración de impactos ecológicos causados por plantas exóticas invasoras: propuesta metodológica

Tanto en España como en Europa existen demasiadas plantas exóticas invasoras para poder afrontar la gestión de todas ellas, por lo que es necesario priorizar las más nocivas. Sin embargo, ello requiere disponer de medidas cuantitativas, sistemáticas y comparables de su impacto. La información disponible es desigual en cuanto a los criterios y variables para medir impactos y por tanto difícil de integrar. Proponemos el siguiente método para integrar medidas de impactos procedentes de distintos estudios: 1) Búsqueda de casos de estudio, 2) cálculo de tamaños del efecto; 3) clasificación de los casos por nivel de organización, 4) integración de los tamaños del efecto para cada especie y nivel de impacto con técnicas de meta-análisis, y 5) estima de un índice de fiabilidad (basado en el número de casos) y otro de consistencia (basado en la heterogeneidad entre casos). Aplicamos este método para estimar los impactos en España de tres árboles invasores (Ailanthus altissima, Robinia pseudoacacia y Ulmus pumila). Encontramos 50 casos para A. altissima, 39 para R. pseudoacacia y 15 para U. pumila. Los impactos en el nivel de ecosistema (fertilidad) fueron los más estudiados, mientras que los de comunidad e individuo están menos documentados. Robinia pseudoacacia tiende a incrementar la fertilidad, mientras que A. altissima no altera esta propiedad. La metodología propuesta tiene la ventaja de permitir estimar el impacto con datos de estudios diversos, pero su aplicación está limitada por la disponibilidad de casos de estudio

Anion Recognition as a Supramolecular Switch of Cell Internalization

The cell internalization of designed oligoarginine peptides equipped with six glutamic acid residues and an anionic pyranine at the N-terminus is triggered upon addition of a supramolecular host. This host binds specifically to the pyranine moiety, enabling the complex to traverse the cell membrane. Interestingly, none of the components, neither the host nor the guest, are able to cross the cell membrane on their ownWe are thankful for the support given by the Spanish grants SAF2013-41943-R, CTQ2015-70698-R, and CTQ2013-49317-EXP, the Consellerı́a de Cultura, Educación e Ordenación Universitaria (GRC2013-041 and Centro singular de investigación de Galicia accreditation 2016-2019, ED431G/09), the European Regional Development Fund (ERDF), and the European Research Council (Advanced Grant No. 340055). Support of the orfeo-cinqa network (CTQ2014-51912-REDC) is kindly acknowledged. J.R. thanks the Xunta de Galicia for her Ph.D. fellowship, and J.M. thanks Fundación Ramón Areces for his postdoctoral fellowshipS

NEXT-100 Technical Design Report (TDR). Executive Summary

In this Technical Design Report (TDR) we describe the NEXT-100 detector that will search for neutrinoless double beta decay (bbonu) in Xe-136 at the Laboratorio Subterraneo de Canfranc (LSC), in Spain. The document formalizes the design presented in our Conceptual Design Report (CDR): an electroluminescence time projection chamber, with separate readout planes for calorimetry and tracking, located, respectively, behind cathode and anode. The detector is designed to hold a maximum of about 150 kg of xenon at 15 bar, or 100 kg at 10 bar. This option builds in the capability to increase the total isotope mass by 50% while keeping the operating pressure at a manageable level. The readout plane performing the energy measurement is composed of Hamamatsu R11410-10 photomultipliers, specially designed for operation in low-background, xenon-based detectors. Each individual PMT will be isolated from the gas by an individual, pressure resistant enclosure and will be coupled to the sensitive volume through a sapphire window. The tracking plane consists in an array of Hamamatsu S10362-11-050P MPPCs used as tracking pixels. They will be arranged in square boards holding 64 sensors (8 times8) with a 1-cm pitch. The inner walls of the TPC, the sapphire windows and the boards holding the MPPCs will be coated with tetraphenyl butadiene (TPB), a wavelength shifter, to improve the light collection.Comment: 32 pages, 22 figures, 5 table

Hydroecology of Amazonian lacustrine Arcellinida (testate amoebae): A case study from Lake Quistococha, Peru

Organic rich sediments were obtained from seven core tops taken in Lake Quistococha, near the city of Iquitos in the Peruvian Amazon. Subsamples from 0 to 4 cm depth in each core were analyzed under dissecting light microscopy to carry out the first investigation of Arcellinida (testate lobose amoebae) from a lacustrine environment in this ecologically important region. The fauna was characterized by a low diversity, low abundance community dominated by centropyxids. This fauna is similar to ‘stressed’ assemblages reported from temperate latitudes, except that test concentrations were two orders of magnitude lower than typical in temperate lakes. Principle arcellinidan stressors in Lake Quistococha likely include the low pH 4 conditions in the lake, and a general lack of suitable minerogenic material to construct tests in the organic rich lake substrate. The low pH conditions are the result of runoff and seepage of water high in dissolved organic carbon from the adjacent similarly low pH 4 terrestrial peatland. The dearth of minerogenic material is the result of the lake being isolated from riverine input for the past ∼2000 years, even during flooding events. Other limiting factors contributing to depressed arcellinidan populations may include nutrient supply, predation pressure, competition, and post-mortem taphonomic factors

The influence of heart disease on characteristics, quality of life, use of health resources, and costs of COPD in primary care settings

<p>Abstract</p> <p>Background</p> <p>To evaluate the influence of heart disease on clinical characteristics, quality of life, use of health resources, and costs of patients with COPD followed at primary care settings under common clinical practice conditions.</p> <p>Methods</p> <p>Epidemiologic, observational, and descriptive study (EPIDEPOC study). Patients ≥ 40 years of age with stable COPD attending primary care settings were included. Demographic, clinical characteristics, quality of life (SF-12), seriousness of the disease, and treatment data were collected. Results were compared between patients with or without associated heart disease.</p> <p>Results</p> <p>A total of 9,390 patients with COPD were examined of whom 1,770 (18.8%) had heart disease and 78% were males. When comparing both patient groups, significant differences were found in the socio-demographic characteristics, health profile, comorbidities, and severity of the airway obstruction, which was greater in patients with heart disease. Differences were also found in both components of quality of life, physical and mental, with lower scores among those patients with heart disease. Higher frequency of primary care and pneumologist visits, emergency-room visits and number of hospital admissions were observed among patients with heart diseases. The annual total cost per patient was significantly higher in patients with heart disease; 2,937 ± 2,957 vs. 1,749 ± 2,120, p < 0.05. Variables that were showed to be independently associated to COPD in subjects with hearth conditions were age, being inactive, ex-smokers, moderate physical exercise, body mass index, concomitant blood hypertension, diabetes, anxiety, the SF-12 physical and mental components and per patient per year total cost.</p> <p>Conclusion</p> <p>Patients with COPD plus heart disease had greater disease severity and worse quality of life, used more healthcare resources and were associated with greater costs compared to COPD patients without known hearth disease.</p