3,801 research outputs found
Integration of a Canine Agent in a Wireless Sensor Network for Information Gathering in Search and Rescue Missions
Search and rescue operations in the context of emergency response to human or natural disasters have the major goal of finding potential victims in the shortest possible time. Multi-agent teams, which can include specialized human respondents, robots and canine units, complement the strengths and weaknesses of each agent, like all-terrain mobility or capability to locate human beings. However, efficient coordination of heterogeneous agents requires specific means to locate the agents, and to provide them with the information they require to complete their mission. The major contribution of this work is an application of Wireless Sensor Networks (WSN) to gather information from a multi-agent team and to make it available to the rest of the agents while keeping coverage. In particular, a canine agent has been equipped with a mobile node installed on a harness, providing information about the dog’s location as well as gas levels. The configuration of the mobile node allows for flexible arrangement of the system, being able to integrate static as well as mobile nodes. The gathered information is available at an external database, so that the rest of the agents and the control center can use it in real time. The proposed scheme has been tested in realistic scenarios during search and rescue exercises
Physical qubits from charged particles: IR divergences in quantum information
We consider soft photons effects (IR structure of QED) on the construction of
physical qubits. Soft-photons appear when we build charged qubits from the
asymptotic states of QED. This construction is necessary in order to include
the effect of soft photons on entanglement measures. The nonexistence of free
charged particles (due to the long range of QED interactions) lead us to
question the sense of the very concept of free charged qubit. In this letter,
using the "dressing" formalism, we build physical charged qubits from dressed
fields which have the correct asymptotic behavior, are gauge invariant, their
propagators have a particle pole structure and are free from infrared
divergences. Finally, we discuss the impact of the soft corrections on the
entanglement measures.Comment: 4 pages, 2 figures, RevTeX. Version 2: Some references update
Sistema móvil de información basado en una red de sensores inalámbricos aplicado a la movilidad urbana
La movilidad en las ciudades se ve comprometida por un tráfico cada vez más elevado y unas infraestructuras que no pueden ampliarse. Por tanto, la mejora de la movilidad y su sostenibilidad deben venir de la mano de una mejor gestión de los recursos, con la incorporación de estrategias de control del tráfico que se adapten en cada momento a sus condiciones. El principal obstáculo está en la obtención de esa información. Una posibilidad son las redes de sensores inalámbricos, que pueden aportar información sobre las condiciones en una zona de interés, con vistas a una planificación más eficiente y al despliegue de algoritmos de control más elaborados.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech. Agencia de Obra Pública de la Junta de Andalucía (proyecto GI3000/IDIZ, con apoyo financiaero de los fondos FEDER
On the resonances and polarizabilities of split ring resonators
In this paper, the behavior at resonance of split ring resonators SRRs and other related topologies,
such as the nonbianisotropic SRR and the broadside-coupled SRR, are studied. It is shown that these
structures exhibit a fundamental resonant mode the quasistatic resonance and other higher-order
modes which are related to dynamic processes. The excitation of these modes by means of a
properly polarized time varying magnetic and/or electric fields is discussed on the basis of resonator
symmetries. To verify the electromagnetic properties of these resonators, simulations based on
resonance excitation by nonuniform and uniform external fields have been performed. Inspection of
the currents at resonances, inferred from particle symmetries and full-wave electromagnetic
simulations, allows us to predict the first-order dipolar moments induced at the different resonators
and to develop a classification of the resonances based on this concept. The experimental data,
obtained in SRR-loaded waveguides, are in agreement with the theory and point out the rich
phenomenology associated with these planar resonant structures.MEC (España)-TEC2004-04249-C02-01 y TEC2004-04249-C02-02Comunidad Europea (programa Eureka)-2895 TELEMACAgencia de Subvenciones de la República Checa-102/03/044
Anthropometric measures as predictive indicators of metabolic risk in a population of “holy week costaleros”
Preventive measures are a priority in those groups that perform intense physical efforts without physical preparation and that can also be overweight or obese. One of the groups that reflect these characteristics is the costaleros of the Holy Week of Andalusia, Spain. This paper aims to describe the effect of obesity on blood pressure. A descriptive cross-sectional study was conducted on 101 costaleros. The anthropometric measures were determined through segmental impedance. Cardiac
recovery and anaerobic power were measured through the Ruffier–Dickson test and the Abalakov test, respectively. Blood pressure was measured when the individuals were at rest. The Kruskal–Wallis test was applied for of continuous parameters and the X2 test for dichotomous measures. Binary logistic regression models were used for the subsequent analysis with R-square and Receiver Operating Characteristic (ROC) curves. The average population was 28 years of age, 173.7 cm tall, and 82.59 Kg weigh. The excess of body fat was 11.27 Kg and Body Mass Index was 27.33 Kg/m2. 72.3% showed abnormal blood pressure and 68.2% were overweight. 32.7% had a waist-hip ratio higher than 0.94. The probability of presenting abnormal blood pressure was higher among the subjects whose fat content was higher and muscle content was lower
Unveiling quantum entanglement degradation near a Schwarzschild black hole
We analyze the entanglement degradation provoked by the Hawking effect in a
bipartite system Alice-Rob when Rob is in the proximities of a Schwarzschild
black hole while Alice is free falling into it. We will obtain the limit in
which the tools imported from the Unruh entanglement degradation phenomenon can
be used properly, keeping control on the approximation. As a result, we will be
able to determine the degree of entanglement as a function of the distance of
Rob to the event horizon, the mass of the black hole, and the frequency of
Rob's entangled modes. By means of this analysis we will show that all the
interesting phenomena occur in the vicinity of the event horizon and that the
presence of event horizons do not effectively degrade the entanglement when Rob
is far off the black hole. The universality of the phenomenon is presented:
There are not fundamental differences for different masses when working in the
natural unit system adapted to each black hole. We also discuss some aspects of
the localization of Alice and Rob states. All this study is done without using
the single mode approximation.Comment: 16 pages, 10 figures, revtex4. Added Journal referenc
Observaciones micro-morfológicas y anatómicas en núculas de Prunella L. y Cleonia L. (Lamiaceae) del suroeste de España
Observaciones micromorfológicas y anatómicas en núnulas de Prunella L. y Cleonia L. (Lamiaceae) del suroeste de España. Se han estudiado las núculas de tres especies del género Prunella y una del género Cleonia, tanto al microscopio óptico como al electrónico de barrido. Los taxones de ambos géneros se diferencian fácilmente tanto mediante caracteres morfológicos como el contorno o la ornamentación, como por caracteres anatómicos como la morfología de las células esclerenquimáticas del mesocarpo. La excreción del mucílago también contribuye a esta diferenciación. Otros caracteres como el color, la presencia o ausencia de glándulas, o algunas diferencias en el mesocarpo o endocarpo permiten diferenciar las tres especies examinadas del género Prunella. Por último, se discute brevemente la utilidad del mucílago, así como los sistemas de dispersión más frecuentes
Clupiter: a Raspberry Pi mini-supercomputer for educational purposes
© 2024 IEEE. This version of the paper has been accepted for publication. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.[Abstract]: The main objective of this work is to bring supercomputing and parallel processing closer to non-specialized audiences by building a Raspberry Pi cluster, called Clupiter, which emulates the operation of a supercomputer. It consists of eight Raspberry Pi devices interconnected to each other so that they can run jobs in parallel. To make it easier to show how it works, a web application has been developed. It allows launching parallel applications and accessing a monitoring system to see the resource usage when these applications are running. The NAS Parallel Benchmarks (NPB) are used as demonstration applications. From this web application a couple of educational videos can also be accessed. They deal, in a very informative way, with the concepts of supercomputing and parallel programming.Clupiter has been supported by grants EDC431C 2021/30 (Xunta de Galicia, Consolidation Program of Competitive Reference Groups) and PID2022-136435NB-I00, funded by MCIN/AEI/ 1 0.13039/501100011033 and by “ERDF A wayof making Europe”, EU.Xunta de Galicia; EDC431C 2021/3
Characterization of the iron-regulated desA promoter of Streptomyces pilosus as a system for controlled gene expression in actinomycetes
BACKGROUND: The bioavailability of iron is quite low since it is usually present as insoluble complexes. To solve the bioavailability problem microorganisms have developed highly efficient iron-scavenging systems based on the synthesis of siderophores that have high iron affinity. The systems of iron assimilation in microorganisms are strictly regulated to control the intracellular iron levels since at high concentrations iron is toxic for cells. Streptomyces pilosus synthesizes the siderofore desferrioxamine B. The first step in desferrioxamine biosynthesis is decarboxylation of L-lysine to form cadaverine, a desferrioxamine B precursor. This reaction is catalyzed by the lysine decarboxylase, an enzyme encoded by the desA gene that is repressed by iron. RESULTS: The binding of the DmdR (acronym for divalent metal dependent repressor) to the desA promoter in presence of Fe(2+ )or other divalent ions has been characterized. A 51 bp DNA fragment of the desA promoter containing the 9 bp inverted repeat was sufficient for binding of the DmdR repressor, as observed by the electrophoretic mobility shift assay. The desA mobility shift was prevented by neutralizing DmdR with anti-DmdR antibodies or by chelating the divalent metal in the binding reaction with 2,2'-dipyridyl. Binding to the desA promoter was observed with purified DmdR repressors of Streptomyces coelicolor or Rhodococcus fascians suggesting that there is a common mechanism of iron-regulation in actinomycetes. The complete desA promoter region was coupled using transcriptional fusions to the amy reporter gene (encoding α-amylase) in low copy or multicopy Streptomyces vectors. The iron-regulated desA promoter was induced by addition of the iron chelating agent 2,2'-dipyridyl resulting in a strong expression of the reporter gene. CONCLUSIONS: The iron-regulated desA promoter can be used for inducible expression of genes in Streptomyces species, as shown by de-repression of the promoter when coupled to a reporter gene
Mental impact of Covid-19 among Spanish healthcare workers. A large longitudinal survey.
Aims
Longitudinal data on the mental health impact of the coronavirus disease 2019 (Covid-19) pandemic in healthcare workers is limited. We estimated prevalence, incidence and persistence of probable mental disorders in a cohort of Spanish healthcare workers (Covid-19 waves 1 and 2) -and identified associated risk factors.
Methods
8996 healthcare workers evaluated on 5 May–7 September 2020 (baseline) were invited to a second web-based survey (October–December 2020). Major depressive disorder (PHQ-8 ≥ 10), generalised anxiety disorder (GAD-7 ≥ 10), panic attacks, post-traumatic stress disorder (PCL-5 ≥ 7), and alcohol use disorder (CAGE-AID ≥ 2) were assessed. Distal (pre-pandemic) and proximal (pandemic) risk factors were included. We estimated the incidence of probable mental disorders (among those without disorders at baseline) and persistence (among those with disorders at baseline). Logistic regression of individual-level [odds ratios (OR)] and population-level (population attributable risk proportions) associations were estimated, adjusting by all distal risk factors, health care centre and time of baseline interview.
Results
4809 healthcare workers participated at four months follow-up (cooperation rate = 65.7%; mean = 120 days S.D. = 22 days from baseline assessment). Follow-up prevalence of any disorder was 41.5%, (v. 45.4% at baseline, p < 0.001); incidence, 19.7% (S.E. = 1.6) and persistence, 67.7% (S.E. = 2.3). Proximal factors showing significant bivariate-adjusted associations with incidence included: work-related factors [prioritising Covid-19 patients (OR = 1.62)], stress factors [personal health-related stress (OR = 1.61)], interpersonal stress (OR = 1.53) and financial factors [significant income loss (OR = 1.37)]. Risk factors associated with persistence were largely similar.
Conclusions
Our study indicates that the prevalence of probable mental disorders among Spanish healthcare workers during the second wave of the Covid-19 pandemic was similarly high to that after the first wave. This was in good part due to the persistence of mental disorders detected at the baseline, but with a relevant incidence of about 1 in 5 of HCWs without mental disorders during the first wave of the Covid-19 pandemic. Health-related factors, work-related factors and interpersonal stress are important risks of persistence of mental disorders and of incidence of mental disorders. Adequately addressing these factors might have prevented a considerable amount of mental health impact of the pandemic among this vulnerable population. Addressing health-related stress, work-related factors and interpersonal stress might reduce the prevalence of these disorders substantially. Study registration number: NCT04556565post-print338 K
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