Algorithmic quantum simulation of memory effects

We propose a method for the algorithmic quantum simulation of memory effects described by integrodifferential evolution equations. It consists in the systematic use of perturbation theory techniques and a Markovian quantum simulator. Our method aims to efficiently simulate both completely positive and nonpositive dynamics without the requirement of engineering non-Markovian environments. Finally, we find that small error bounds can be reached with polynomially scaling resources, evaluated as the time required for the simulation

Determinación del eje de la carretera y la distancia de visibilidad utilizando datos GPS y herramientas SIG

Hoy en día, tanto en el proceso de diseño de las carreteras como en el análisis del funcionamiento de las ya construidas, se está dando cada vez más importancia a la seguridad vial. Entre los distintos aspectos que se consideran se encuentra la distancia de visibilidad. Por otra parte, uno de los problemas que aparecen en la práctica al tratar de analizar carreteras en servicio es la falta de datos de la geometría del eje que estén actualizados y tengan la precisión requerida. En esta comunicación se presenta un procedimiento para determinar el eje de la carretera mediante información GPS y calcular la distancia de visibilidad aplicando herramientas SIG. El procedimiento se ha aplicado a un tramo de carretera convencional de doble sentido de circulación. El método propuesto puede ser especialmente útil en aquellas carreteras en servicio y de las que, por no contar con la información sobre su trazado (original o posteriores modificaciones), no es posible utilizar los programas de diseño de carreteras para el cálculo de la distancia de visibilidad.Nowadays road safety aspects are very important, both for the designing process and for the analysis of already built roads. Sight distance is one of the most important road safety aspects to consider. On the other hand, the geometric definition of already built roads is one of the most difficult issues that arise in practice. This road geometry must be accurate and up to date. In this paper, a procedure to determine the alignment of a road using a GPS and to calculate sight distances using GIS tools is presented. Also, the use of this procedure in a two-lane rural road is described. The proposed method can be especially useful for those roads whose design data are not available because, on them, road design software could not be used for sight distance calculation

Accuracy and precision of GPS receivers under forest canopies in a mountain environment

Abstract Georeferencing field plots by means of GPS/GLONASS techniques is becoming compulsory for many applications concerning forest management and inventory. True coordinates obtained in a total station traverse were compared against GPS/GLONASS occupations computed from one navigation-grade and three survey-grade receivers. Records were taken under a high Pinus sylvestris L. forest canopy situated in a mountainous area in central Spain. The horizontal component of the absolute error was a better descriptor of the performance of GPS/GLONASS receivers compared to the precision computed by the proprietary software. The vertical component of absolute error also failed to show the effects revealed when the horizontal one was studied. These differences might be critical for applications involving high-demanding surveys, in which a comparison against a terrestrially surveyed ground truth is still mandatory for accuracy assessment in forested mountainous areas. Moreover, a comparison of diverse Differential GPS/GLONASS techniques showed that the effect of lengthening the baseline and lowering the logging rate was not significant in this study. Differences among methods and receivers were only observed for recording periods between 5 and 15 minutes. The hand-held receiver was inappropriate for plot establishment due to its inaccuracy and a low rate of fixed solutions, though it may be used for forest campaigns tolerating low precision or permitting the employment of periods of 20 minutes or longer for plot mensuration. Additional key words: forest inventory; georeferencing; global navigation satellite system (GNSS) (GLONASS); optimum observing time. Resumen Exactitud y precisión de receptores GPS bajo cubiertas forestales en ambientes montañosos La georreferenciación de trabajos de campo por medio de GPS/GLONASS es cada vez más necesaria para muchas aplicaciones en la gestión e inventario forestal. Se compararon coordenadas reales levantadas con estación total con las obtenidas por un navegador y tres equipos de calidad topográfica. Los registros se efectuaron bajo una masa de Pinus sylvestris L. del Sistema Central, España. La componente horizontal del error absoluto resultó ser un mejor descriptor de la calidad de las mediciones de los receptores GPS/GLONASS que los valores de precisión proporcionados por el software de los equipos. La componente vertical del error absoluto no mostró los efectos revelados por la componente horizontal. Estas diferencias pueden ser críticas para trabajos que requieran levantamientos topográficos de precisión, en los cuáles un contraste con itinerarios de validación sobre el terreno sigue siendo indispensable para calcular la exactitud en áreas forestales montañosas. Por otro lado, la comparación de diversas técnicas de GPS/GLO-NASS diferencial mostró que los cambios en la longitud de la línea base y de la tasa de registros no fueron significativos en este estudio. Sólo se observaron diferencias ente los métodos y receptores para tiempos de registro de 5 a 15 minutos. El navegador no resultó adecuado para el establecimiento de parcelas debido a la inexactitud y baja tasa de soluciones fijadas, pero puede ser utilizado en campañas que toleren bajas precisiones y permitan tiempos de registro iguales o superiores a 20 minutos para las medias forestales. Palabras clave adicionales

Lost Generation: System Resilience and Flexibility

Whole energy system modelling is a valuable tool to support the development of policy to decarbonise energy systems, and has been used extensively in the UK for this purpose. However, quantitative insights produced by such models methods necessarily omit potentially important features of physical and engineering reality. The authors argue that important socio-technical insights can be gained by studying critical events such as the loss of 2.1 GW generation from the electricity system of Great Britain in August, 2019. The present paper uses this event as a starting point for a discussion of the need for additional tools, drawn from the System Architecture literature, to support the design and realisation of future fully decarbonised systems with high penetrations of renewable energy, capable of providing high levels of resilience and flexibility

A combined high-pressure experimental and theoretical study of the electronic band-structure of scheelite-type AWO4 (A = Ca, Sr, Ba, Pb) compounds

The optical-absorption edge of single crystals of CaWO4, SrWO4, BaWO4, and PbWO4 has been measured under high pressure up to ~20 GPa at room temperature. From the measurements we have obtained the evolution of the band-gap energy with pressure. We found a low-pressure range (up to 7-10 GPa) where alkaline-earth tungstates present a very small Eg pressure dependence (-2.1 < dEg/dP < 8.9 meV/GPa). In contrast, in the same pressure range, PbWO4 has a pressure coefficient of -62 meV/GPa. The high-pressure range is characterized in the four compounds by an abrupt decrease of Eg followed by changes in dEg/dP. The band-gap collapse is larger than 1.2 eV in BaWO4. We also calculated the electronic-band structures and their pressure evolution. Calculations allow us to interpret experiments considering the different electronic configuration of divalent metals. Changes in the pressure evolution of Eg are correlated with the occurrence of pressure-induced phase transitions. The band structures for the low- and high-pressure phases are also reported. No metallization of any of the compounds is detected in experiments nor is predicted by calculations.Comment: 26 pages, 1 table, 6 figure

Transcription of toll-like receptors 2, 3, 4 and 9, FoxP3 and Th17 cytokines in a susceptible experimental model of canine Leishmania infantum infection

Canine leishmaniosis (CanL) due to Leishmania infantum is a chronic zoonotic systemic disease resulting from complex interactions between protozoa and the canine immune system. Toll-like receptors (TLRs) are essential components of the innate immune system and facilitate the early detection of many infections. However, the role of TLRs in CanL remains unknown and information describing TLR transcription during infection is extremely scarce. The aim of this research project was to investigate the impact of L. infantum infection on canine TLR transcription using a susceptible model. The objectives of this study were to evaluate transcription of TLRs 2, 3, 4 and 9 by means of quantitative reverse transcription polymerase chain reaction (qRT-PCR) in skin, spleen, lymph node and liver in the presence or absence of experimental L. infantum infection in Beagle dogs. These findings were compared with clinical and serological data, parasite densities in infected tissues and transcription of IL-17, IL-22 and FoxP3 in different tissues in non-infected dogs (n = 10), and at six months (n = 24) and 15 months (n = 7) post infection. Results revealed significant down regulation of transcription with disease progression in lymph node samples for TLR3, TLR4, TLR9, IL-17, IL-22 and FoxP3. In spleen samples, significant down regulation of transcription was seen in TLR4 and IL-22 when both infected groups were compared with controls. In liver samples, down regulation of transcription was evident with disease progression for IL-22. In the skin, upregulation was seen only for TLR9 and FoxP3 in the early stages of infection. Subtle changes or down regulation in TLR transcription, Th17 cytokines and FoxP3 are indicative of the silent establishment of infection that Leishmania is renowned for. These observations provide new insights about TLR transcription, Th17 cytokines and Foxp3 in the liver, spleen, lymph node and skin in CanL and highlight possible markers of disease susceptibility in this model

Secure quantum remote state preparation of squeezed microwave states

Quantum communication protocols based on nonclassical correlations can be more efficient than known classical methods and offer intrinsic security over direct state transfer. In particular, remote state preparation aims at the creation of a desired and known quantum state at a remote location using classical communication and quantum entanglement. We present an experimental realization of deterministic continuous-variable remote state preparation in the microwave regime over a distance of 35 cm. By employing propagating two-mode squeezed microwave states and feedforward, we achieve the remote preparation of squeezed states with up to 1.6 dB of squeezing below the vacuum level. We quantify security in our implementation using the concept of the one-time pad. Our results represent a significant step towards microwave quantum networks between superconducting circuits.Comment: Main text: 6 pages, 4 figures; Supplementary Information: 8 pages, 5 figure

Non-expanded adipose stromal vascular fraction cell therapy for multiple sclerosis

The stromal vascular fraction (SVF) of adipose tissue is known to contain mesenchymal stem cells (MSC), T regulatory cells, endothelial precursor cells, preadipocytes, as well as anti-inflammatory M2 macrophages. Safety of autologous adipose tissue implantation is supported by extensive use of this procedure in cosmetic surgery, as well as by ongoing studies using in vitro expanded adipose derived MSC. Equine and canine studies demonstrating anti-inflammatory and regenerative effects of non-expanded SVF cells have yielded promising results. Although non-expanded SVF cells have been used successfully in accelerating healing of Crohn's fistulas, to our knowledge clinical use of these cells for systemic immune modulation has not been reported. In this communication we discuss the rationale for use of autologous SVF in treatment of multiple sclerosis and describe our experiences with three patients. Based on this rationale and initial experiences, we propose controlled trials of autologous SVF in various inflammatory conditions

T helper cell subsets specific for pseudomonas aeruginosa in healthy individuals and patients with cystic fibrosis

Background: We set out to determine the magnitude of antigen-specific memory T helper cell responses to Pseudomonas aeruginosa in healthy humans and patients with cystic fibrosis. Methods: Peripheral blood human memory CD4+ T cells were co-cultured with dendritic cells that had been infected with different strains of Pseudomonas aeruginosa. The T helper response was determined by measuring proliferation, immunoassay of cytokine output, and immunostaining of intracellular cytokines. Results: Healthy individuals and patients with cystic fibrosis had robust antigen-specific memory CD4+ T cell responses to Pseudomonas aeruginosa that not only contained a Th1 and Th17 component but also Th22 cells. In contrast to previous descriptions of human Th22 cells, these Pseudomonal-specific Th22 cells lacked the skin homing markers CCR4 or CCR10, although were CCR6+. Healthy individuals and patients with cystic fibrosis had similar levels of Th22 cells, but the patient group had significantly fewer Th17 cells in peripheral blood. Conclusions: Th22 cells specific to Pseudomonas aeruginosa are induced in both healthy individuals and patients with cystic fibrosis. Along with Th17 cells, they may play an important role in the pulmonary response to this microbe in patients with cystic fibrosis and other conditions