789 research outputs found
Progress toward scalable tomography of quantum maps using twirling-based methods and information hierarchies
We present in a unified manner the existing methods for scalable partial
quantum process tomography. We focus on two main approaches: the one presented
in Bendersky et al. [Phys. Rev. Lett. 100, 190403 (2008)], and the ones
described, respectively, in Emerson et al. [Science 317, 1893 (2007)] and
L\'{o}pez et al. [Phys. Rev. A 79, 042328 (2009)], which can be combined
together. The methods share an essential feature: They are based on the idea
that the tomography of a quantum map can be efficiently performed by studying
certain properties of a twirling of such a map. From this perspective, in this
paper we present extensions, improvements and comparative analyses of the
scalable methods for partial quantum process tomography. We also clarify the
significance of the extracted information, and we introduce interesting and
useful properties of the -matrix representation of quantum maps that can
be used to establish a clearer path toward achieving full tomography of quantum
processes in a scalable way.Comment: Replaced with published version (only minor changes respect to the
first version
Distribution and Outcomes of a Phenotype- Based Approach to Guide COPD Management: Results from the CHAIN Cohort
Rationale The Spanish guideline for COPD (GesEPOC) recommends COPD treatment according to
four clinical phenotypes: non-exacerbator phenotype with either chronic bronchitis or emphy-
sema (NE), asthma-COPD overlap syndrome (ACOS), frequent exacerbator phenotype with
emphysema (FEE) or frequent exacerbator phenotype with chronic bronchitis (FECB). How-
ever, little is known on the distribution and outcomes of the four suggested phenotypes.
Objective
We aimed to determine the distribution of these COPD phenotypes, and their relation with
one-year clinical outcomes.
Methods
We followed a cohort of well-characterized patients with COPD up to one-year. Baseline
characteristics, health status (CAT), BODE index, rate of exacerbations and mortality up to
one year of follow-up were compared between the four phenotypes.
Results
Overall, 831 stable COPD patients were evaluated. They were distributed as NE, 550
(66.2%); ACOS, 125 (15.0%); FEE, 38 (4.6%); and FECB, 99 (11.9%); additionally 19
(2.3%) COPD patients with frequent exacerbations did not fulfill the criteria for neither FEE
nor FECB. At baseline, there were significant differences in symptoms, FEV 1 and BODE
index (all p<0.05). The FECB phenotype had the highest CAT score (17.1±8.2, p<0.05
compared to the other phenotypes). Frequent exacerbator groups (FEE and FECB) were
receiving more pharmacological treatment at baseline, and also experienced more exacer-
bations the year after (all p<0.05) with no differences in one-year mortality. Most of NE
(93%) and half of exacerbators were stable after one year.
Conclusions
There is an uneven distribution of COPD phenotypes in stable COPD patients, with signifi-
cant differences in demographics, patient-centered outcomes and health care resources
use
Exploiting hydrogen bonding to direct supramolecular polymerization at the air/water interface
Fluid interfaces provide an advanced platform for directed self-assembly of organic composites and formation of supramolecular polymers (SPs). Intermolecular interactions govern the supramolecular polymerization processes, with hydrogen bonding (H-bonding) as a key interaction in supramolecular chemistry and biology. Two purposefully designed supra-amphiphiles for assessing the role of H-bonding were designed and their supramolecular polymerization (SP) at the air/water interface was compared. H-bonding was confirmed by in situ experimental and computational techniques as the required intermolecular interaction for attaining SPs with well-defined molecular arrangement. Control of H-bonding as opposite to traditionally considered interactions, e.g., π-π stacking is proposed as a successful strategy for SP at fluid interfaces
Conservation of aging and cancer epigenetic signatures across human and mouse
Aging and cancer are two interrelated processes, with aging being a major risk factor for the development of cancer. Parallel epigenetic alterations have been described for both, although differences, especially within the DNA hypomethylation scenario, have also been recently reported. While many of these observations arise from the use of mouse models, there is a lack of systematic comparisons of human and mouse epigenetic patterns in the context of disease. However, such comparisons are significant as they allow to establish the extent to which some of the observed similarities or differences arise from pre-existing species-specific epigenetic traits. Here, we have used reduced representation bisulfite sequencing to profile the brain methylomes of young and old, tumoral and non-tumoral brain samples from human and mouse. We first characterized the baseline epigenomic patterns of the species and subsequently focused on the DNA methylation alterations associated with cancer and aging. Next, we described the functional genomic and epigenomic context associated with the alterations, and finally we integrated our data to study interspecies DNA methylation levels at orthologous CpG sites. Globally, we found considerable differences between the characteristics of DNA methylation alterations in cancer and aging in both species. Moreover, we describe robust evidence for the conservation of the specific cancer and aging epigenomic signatures in human and mouse. Our observations point towards the preservation of the functional consequences of these alterations at multiple levels of genomic regulation. Finally, our analyses reveal a role for the genomic context in explaining disease- and species-specific epigenetic traits.© The Author(s) 2020. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution
COPD Clinical Control: predictors and long-term follow-up of the CHAIN cohort
CHAIN Study Investigators.[Background] Control in COPD is a dynamic concept that can reflect changes in patients’ clinical status that may have prognostic implications, but there is no information about changes in control status and its long-term consequences.[Methods] We classified 798 patients with COPD from the CHAIN cohort as controlled/uncontrolled at baseline and over 5 years. We describe the changes in control status in patients over long-term follow-up and analyze the factors that were associated with longitudinal control patterns and related survival using the Cox hazard analysis.[Results] 134 patients (16.8%) were considered persistently controlled, 248 (31.1%) persistently uncontrolled and 416 (52.1%) changed control status during follow-up. The variables significantly associated with persistent control were not requiring triple therapy at baseline and having a better quality of life. Annual changes in outcomes (health status, psychological status, airflow limitation) did not differ in patients, regardless of clinical control status. All-cause mortality was lower in persistently controlled patients (5.5% versus 19.1%, p = 0.001). The hazard ratio for all-cause mortality was 2.274 (95% CI 1.394–3.708; p = 0.001). Regarding pharmacological treatment, triple inhaled therapy was the most common option in persistently uncontrolled patients (72.2%). Patients with persistent disease control more frequently used bronchodilators for monotherapy (53%) at recruitment, although by the end of the follow-up period, 20% had scaled up their treatment, with triple therapy being the most frequent therapeutic pattern.[Conclusions] The evaluation of COPD control status provides relevant prognostic information on survival. There is important variability in clinical control status and only a small proportion of the patients had persistently good control. Changes in the treatment pattern may be relevant in the longitudinal pattern of COPD clinical control. Further studies in other populations should validate our results.[Trial registration] Clinical Trials.gov: identifier NCT01122758.This study has been funded by AstraZeneca.Peer reviewe
Mejoras en el diseño agronómico de la instalación de riego dirigidas al aumento de la productividad técnica y económica del agua en limonero temprano
El objetivo del trabajo fue incrementar la productividad en limonero temprano mediante mejoras en el diseño agronómico de la red de riego. El ensayo se llevó a cabo en una parcela experimental en Torre Pacheco (Murcia), en árboles adultos de limonero ‘Fino 49’ injertados sobre Citrus macrophylla Wester. Se han evaluado dos diseños del sistema de riego: diseño convencional (2L), con dos tuberías portagoteros (6 goteros árbol-1); y un diseño con mayor superficie mojada (3L), con tres tuberías (9 goteros árbol-1). Partiendo de los resultados agronómicos, se ha realizado un análisis económico comparativo entre dos diseños del sistema de riego. El diseño 3L fue el más productivo técnica y económicamente. El Producto Bruto Económico (PBE) fue un 14% superior en el diseño 3L respecto al 2L; el Producto Bruto Técnico (PBT) lo fue en un 6,2%. Este resultado se debe a dos motivos: por un lado y en mayor medida, al incremento en la proporción de limón de primer corte del diseño 3L y, por otro lado, a la disminución de limón derivado a la industria. El Margen Bruto (MB) sigue la misma pauta que el Producto Bruto (PB), ya que los costes diferenciales (CD) son de poca envergadura. El precio ponderado del kg de limón medio (PBE/PBT) es de 0,367 € kg-1 y 0,341 € kg-1, en 3L y 2L, respectivamente, y supone un ingreso de 2.631 € extras por hectárea y año a favor del sistema 3L. Por último, resaltar que el diseño 3L destaca principalmente por ser es más productivo económicamente, en relación al agua aplicada (€ m-3)
Reproductive parameters of the Turquoise-fronted Parrot (Amazona aestiva) in the dry Chaco forest
Fil: Berkunsky, Igor. Universidad Nacional del Centro de la provincia de Buenos Aires. Instituto Multidisciplinario sobre Ecosistemas y Desarrollo Sustentable; ArgentinaFil: Segura, Luciano Noel. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Zoología Vertebrados; ArgentinaFil: Ruggera, Román A.. Universidad Nacional de Jujuy. Facultad de Ciencias Agrarias; ArgentinaFil: Faegre, Sarah I. K.. University of Washington. Rota Avian Behavioral Ecology Program; United StatesFil: Trofino-Falasco, Clara. Universidad Nacional del Centro de la provincia de Buenos Aires. Instituto Multidisciplinario sobre Ecosistemas y Desarrollo Sustentable; ArgentinaFil: López, Fernando G.. Universidad Nacional de La Pampa. Instituto de Ciencias de la Tierra y Ambientales de La Pampa. Centro para el Estudio y Conservación de las Aves Rapaces en Argentina; ArgentinaFil: Velasco, Melina Alicia. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Zoología Vertebrados; ArgentinaFil: Kacoliris, Federico Pablo. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Zoología Vertebrados; ArgentinaFil: Aramburú, Rosana Mariel. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Zoología Vertebrados; ArgentinaFil: Reboreda, Juan Carlos. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ecología, Genética y Evolución; Argentin
The Maser-emitting Structure and Time Variability of the SiS Lines J =14-13 and 15-14 in IRC+10216
2 pags., 1 tab. -- Why Galaxies Care About AGB Stars: A Continuing Challenge through Cosmic Time Proceedings IAU Symposium No. 343, 2019
F. Kerschbaum, M. Groenewegen & H. Olofsson, eds.AGB stars are important contributors of processed matter to the ISM. However, the physical and chemical mechanisms involved in its ejection are still poorly known. This process is expected to have remarkable effects in the innermost envelope, where the dust grains are formed, the gas is accelerated, the chemistry is active, and the radiative excitation becomes important. A good tracer of this region in C-rich stars is SiS, an abundant refractory molecule that can display maser lines, very sensitive to changes in the physical conditions. We present high angular resolution interferometer observations (HPBW â‰30.″.25) of the v = 0 J = 14-13 and 15-14 SiS maser lines towards the archetypal AGB star IRC+10216, carried out with CARMA and ALMA to explore the inner 1> region around the central star. We also present an ambitious monitoring of these lines along one single pulsation period carried out with the IRAM 30 m telescope.The research leading to these results has received funding from the European Research
Council under the European Union’s Seventh Framework Programme (FP7/2007-2013)/
ERC grant agreement n◦ 610256: NANOCOSMO
Use of sonic tomography to detect and quantify wood decay in living trees.
Premise of the studyField methodology and image analysis protocols using acoustic tomography were developed and evaluated as a tool to estimate the amount of internal decay and damage of living trees, with special attention to tropical rainforest trees with irregular trunk shapes.Methods and resultsLiving trunks of a diversity of tree species in tropical rainforests in the Republic of Panama were scanned using an Argus Electronic PiCUS 3 Sonic Tomograph and evaluated for the amount and patterns of internal decay. A protocol using ImageJ analysis software was used to quantify the proportions of intact and compromised wood. The protocols provide replicable estimates of internal decay and cavities for trees of varying shapes, wood density, and bark thickness.ConclusionsSonic tomography, coupled with image analysis, provides an efficient, noninvasive approach to evaluate decay patterns and structural integrity of even irregularly shaped living trees
A Method for Modeling Decoherence on a Quantum Information Processor
We develop and implement a method for modeling decoherence processes on an
N-dimensional quantum system that requires only an -dimensional quantum
environment and random classical fields. This model offers the advantage that
it may be implemented on small quantum information processors in order to
explore the intermediate regime between semiclassical and fully quantum models.
We consider in particular system-environment couplings which
induce coherence (phase) damping, though the model is directly extendable to
other coupling Hamiltonians. Effective, irreversible phase-damping of the
system is obtained by applying an additional stochastic Hamiltonian on the
environment alone, periodically redressing it and thereby irreversibliy
randomizing the system phase information that has leaked into the environment
as a result of the coupling. This model is exactly solvable in the case of
phase-damping, and we use this solution to describe the model's behavior in
some limiting cases. In the limit of small stochastic phase kicks the system's
coherence decays exponentially at a rate which increases linearly with the kick
frequency. In the case of strong kicks we observe an effective decoupling of
the system from the environment. We present a detailed implementation of the
method on an nuclear magnetic resonance quantum information processor.Comment: 12 pages, 9 figure
- …