1,124 research outputs found
Photoluminescence upconversion at GaAs/InGaP2 interfaces driven by a sequential two-photon absorption mechanism
This paper reports on the results of an investigation into the nature of photoluminescence upconversion at
GaAs/InGaP2 interfaces. Using a dual-beam excitation experiment, we demonstrate that the upconversion in our
sample proceeds via a sequential two-photon optical absorption mechanism. Measurements of photoluminescence
and upconversion photoluminescence revealed evidence of the spatial localization of carriers in the InGaP2
material, arising from partial ordering of the InGaP2. We also observed the excitation of a two-dimensional electron
gas at the GaAs/InGaP2 heterojunction that manifests as a high-energy shoulder in the GaAs photoluminescence
spectrum. Furthermore, the results of upconversion photoluminescence excitation spectroscopy demonstrate that
the photon energy onset of upconversion luminescence coincides with the energy of the two-dimensional electron
gas at the GaAs/InGaP2 interface, suggesting that charge accumulation at the interface can play a crucial role in
the upconversion process
Multinet : enabler for next generation enterprise wireless services
Wireless communications are currently experiencing a fast migration toward the beyond third-generation (B3G)/fourth generation (4G) era. This represents a generational change in wireless systems: new capabilities related to mobility and new services support is required and new concepts as individual-centric, user-centric or ambient-aware communications are included. One of the main restrictions associated to wireless technology is mobility management, this feature was not considered in the design phase; for this reason, a complete solution is not already found, although different solutions are proposed and are being proposed. In MULTINET project, features as mobility and multihoming are applied to wireless network to provide the necessary network and application functionality enhancements for seamless data communication mobility considering end-user scenario and preferences. The aim of this paper is to show the benefits of these functionalities from the Service Providers and final User point of view
Influence of the adequacy of data collection, during two years, in the management of communityacquired pneumonia in emergency departments
Objective. The aim of this study was to
analyze whether structured data collection
of patients with community-acquired
pneumonia (CAP) in the Emergency Department
(ED) improves compliance with
clinical guidelines regarding inpatient and
outpatient treatment and prescription of
antibiotics at discharge.
Material and methods. We performed a
quasi experimental, multicenter, pre/postintervention
study. The intervention consisted
of basic training for the participating
physicians and the incorporation of a
data collection sheet in the clinical history
chart, including the information necessary
for adequate decision making regarding
patient admission and treatment,
in the case of discharge. We analyzed the
adequacy of the final destination of patients
classified as Fine I-II and antibiotic
treatment in patients receiving outpatient
treatment, with each participating physician
including 8 consecutive patients (4
pre-intervention and 4 post-intervention).
Results. A total of 738 patients were included:
378 pre-intervention and 360
post-intervention. In the pre-intervention
group, Fine V was more frequent and patients
were older, had more ischemic heart
disease, active neoplasms and fewer risk
factors for atypical pneumonia. Of the
patients with Fine I-II, 23.7% were inadequately
admitted and 19.6% of those
discharged received treatment not recommended
by guidelines. No differences
were observed in the target variables between
the two groups.
Conclusion. The adequacy of the decision
to admit patients with Fine I-II CAP and
outpatient antibiotic treatment can be improved
in the ED. Structured data collection
does not improve patient outcome
Recovery of early meteorological records from Extremadura region (SW Iberia): The ''CliPastExtrem'' (v1.0) database
In this work, we provide instrumental meteorological data recovered for the Extremadura region (interior SW Iberia), from 1826 to mid-20th century. Meteorological variables such as air temperature, atmospheric pressure, precipitation, wind direction and humidity, among others, were retrieved. In total, more than 750 000 instrumental data in 157 meteorological series belonging to 131 different locations throughout Extremadura were rescued. It must be noted that daily resolution data constitutes 80% of the database. This great effort of digitization and data collection has been carried out with the aim of contributing to a significant expansion of the length of the databases with meteorological information in this region. Therefore, this database will provide a better understanding of climate variability, trends and extreme events of the Extremadura region
Polyfire project- an example of an industrial research project promoting safe industrial production of fire-resistant nanocomposites
New developments based on nanotechnology have to guarantee safe products and processes to be accepted by society. The Polyfire project will develop and scale-up techniques for processing halogen-free, fire-retardant nanocomposite materials and coatings based on unsaturated polyester resins and organoclays. The project includes a work package that will assess the Health and Environmental impacts derived from the manipulation of nanoparticles. This work package includes the following tasks: (1) Identification of Health and Environment Impacts derived from the processes, (2) Experimentation to study specific Nanoparticle Emissions, (3) Development of a Risk Management Methodology for the process, and (4) A Comparison of the Health and Environmental Impact of New and Existing Materials. To date, potential exposure scenarios to nanomaterials have been identified through the development of a Preliminary Hazard Analysis (PHA) of the new production processes. In the next step, these scenarios will be studied and simulated to evaluate potential emissions of nanomaterials. Polyfire is a collaborative European project, funded by the European Commission 7th Framework Programme (Grant Agreement No 229220). It features 11 partners from 5 countries (5 SMEs, 3 research institutes, 2 large companies, 1 association) and runs for three years (1st September 2009 – 31st August 2012). This project is an example of an industrial research development which aims to introduce to the market new products promoting the safe use of nanomaterials
Structure and photoactivity for hydrogen production of CdS nanorods modified with In, Ga, Ag-In and Ag-Ga and prepared by solvothermal method
This work studies the variation in the photocatalytic properties of CdS derived from the insertion of In,
Ga, Ag-In and Ag-Ga in the CdS lattice through solvothermal methodology. Solvothermal synthesis of
CdS-M photocatalysts has been succesful for the insertion of Ga3þ, In3þ, Ga3þ/Agþ and In3þ/Agþ into the
hexagonal crystal lattice of one-dimensional CdS. The insertion of In, Ga, Ag-In and Ag-Ga modifies the
band gap and the relative position of EVB. CdS modified with In3þ or Ga3þ shows an increase in the band
gap and upshift in the relative position of the valence band energy which leads to a low efficiency
hydrogen production. The co-addition of Agþ-In3þ or Agþ-Ga3þ favours the insertion of Agþ ions into the
CdS lattice with narrower band gap. Of all the co-substituted photocatalysts, the CdS-AgGa was the only
one that showed a higher photoactivity with respect to the CdS. The increase in the photoactivity of the
CdS-AgGa photocatalyst is related to the band gap narrowing and downshift in the relative position of
the valence band energy which enhance their visible light absorption and potential for oxidation. The
CdS-AgGa photocatalyst shows small segregation of metallic Ag nanoparticles at the surface which also
assist in the photoactivity of the sample.publishe
Variabilidad del método Folin-Denis en la determinación de equivalentes de ácido tánico en muestras de sorgo
The purpose of this work is to evaluate the influence of some factor that condition the variability of the Folin-Denis method to determine de equivalents of tannic acid in grain of sorghum. We studied the influence of the centrifugation previous to the spectrophotometric measurement. It was also studied the most convenient refluxed time for the extraction of tannic substances. The application of centrifugation to the aqueous extract after a night rest showed highly significant differences (p< 0,01) with respect to the sample without centrifugation. Considering both procedures, we got "r" 0,997 and the equation of regressi0n responds to y = 0,0627 + 1,033 x. The coefficient of variations fluctuates between 1,94 and 5,77 % for samples without centrifugation and between 0,71 and 3,85 % for samples with centrifugation. Therefore, in order to decrease the variability of the methods it is convenient to apply a ten-minute centrifugation at 5.000 rpm to the aqueous extract. It was determined that for the refluxe time there are no differences of extraction between 2 and 5 hours, though it tends to increase as time increases. For routine determinations a 3 hours refluxe extraction is enough but 5 hours are advisable for greater precision.El propósito del presente trabajo es evaluar la influencia de algunos factores que condicionan la variabilidad del método de Folin-Denis para determinar equivalentes de ácido tánico en grano de sorgo. Se estudió la influencia de la centrifugación previa a la medición espectrofotométrica y el tiempo de reflujo más conveniente para la extracción de sustancias tánicas. La aplicación de centrifugación al extracto acuoso, previo reposo de toda la noche, mostró diferencias altamente significativas (p<0,01) con respecto al testigo sin centrifugar. Entre ambos procedimientos se obtuvo "r" = 0,997 y la ecuación de regresión responde a y = 0,0627 + 1,033 x. Los coeficientes de variación oscilaron entre 1,94 y 5,77 % para muestras sin centrifugar y 0,71 a 3,85 % con centrifugación. Por 10 tanto para disminuir la variabilidad del método conviene aplicar una centrifugación de 10 minutos a 500,0 r.p.m. al extracto acuoso. Para el tiempo de reflujo se determinó que existen diferencias de extracción entre 2 y 5 horas, aunque tiende a aumentar a medida que se incrementa el tiempo. Para determinaciones de rutina es suficiente una extracción de tres horas de reflujo, aunque para mayor precisión se recomiendan 5 horas
Validation of a DNA methylation microarray for 285,000 CpG sites in the mouse genome
Mouse has been extensively used as a model organism in many studies to characterize biological pathways and drug effects and to mimic human diseases. Similar DNA sequences between both species facilitate these types of experiments. However, much less is known about the mouse epigenome, particularly for DNA methylation. Progress in delivering mouse DNA methylomes has been slow due to the currently available time-consuming and expensive methodologies. Following the great acceptance of the human DNA methylation microarrays, we have herein validated a newly developed DNA methylation microarray (Infinium Mouse Methylation BeadChip) that interrogates 280,754 unique CpG sites within the mouse genome. The CpGs included in the platform cover CpG Islands, shores, shelves and open sea sequences, and loci surrounding transcription start sites and gene bodies. From a functional standpoint, mouse ENCODE representative DNase hypersensitivity sites (rDHSs) and candidate cis-Regulatory Elements (cCREs) are also included. Herein, we show that the profiled mouse DNA methylation microarray provides reliable values among technical replicates; matched results from fresh frozen versus formalin-fixed samples; detects hemimethylated X-chromosome and imprinted CpG sites; and is able to determine CpG methylation changes in mouse cell lines treated with a DNA demethylating agent or upon genetic disruption of a DNA methyltransferase. Most important, using unsupervised hierarchical clustering and t-SNE approaches, the platform is able to classify all types of normal mouse tissues and organs. These data underscore the great features of the assessed microarray to obtain comprehensive DNA methylation profiles of the mouse genome.We thank the CERCA Programme/Generalitat de Catalunya for institutional support. This work was supported by the Health Department PERIS-project no. SLT/002/16/00374 and AGAUR-project no. 2017SGR1080 of the Catalan Government (Generalitat de Catalunya); Ministerio de Ciencia e Innovación (MCI), Agencia Estatal de Investigación (AEI), and European Regional Development Fund (ERDF) project no. RTI2018-094049-B-I00 and PID2020-117284RB-I00; the Cellex Foundation; Marie Sklodowska-Curie Fellowship no. 895979 from the European Commission (BNV); and ‘la Caixa’ Banking Foundation (LCF/PR/GN18/51140001).Peer ReviewedPostprint (published version
Estudio comparativo de cuatro variedades de alfalfa restringiendo macroelentos mediante ensayos en macetas
Estudio comparativo de cuatro variedades de alfalfa restringiendo macroelentos mediante ensayos en maceta
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