99 research outputs found

    Modification of the spectroscopic properties of Tb2O3 phosphor under the high-pressure phase transitions sequence

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    The high-pressure behavior of cubic Tb2O3 phase (C-type) has been investigated by in situ photoluminescence and Raman spectroscopy up to 18 GPa and 22 GPa, respectively. The luminescence spectrum of Tb2O3 at ambient conditions shows its characteristic sharp-line emission bands with the most intense one corresponding to the 5D4 - 7F5 transition, responsible of the green emission. Excitation and emission spectra measured at low temperature and at different emission and excitation wavelengths suggest that photoluminescence is governed by the Tb3+ in the non-centrosymmetric site (C2). A phase transition between 7.2 and 8.6 GPa is observed by Raman and photoluminescence experiments and is associated to a cubic-to-monoclinic (B-type) structural transformation. From 14 GPa the predominant modes in the Raman spectrum correspond to those from the trigonal phase (A-type), indicating that the pressure-induced structural phase transition sequence of Tb2O3 is C → B → A. Upon pressure release, the starting cubic phase is not recovered, but the monoclinic one.M.T. Candela would like to thank University of Cantabria for her pre-doctoral grant “Concepción Arenal”, co-financed by the Government of Cantabria. Also, the authors acknowledge financial support from both, the European Research Council (ref NCLas H2020-EU829161) and the Spanish Ministerio de Ciencia, Innovación y Universidades (PGC2018-101464-B-I00)

    Non-resonant energy transfer from Eu3+ to Yb3+ in C-type and B-type (Eu1-xYbx)2O3 nanocrystals

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    The structural and spectroscopic properties of (Eu1-xYbx)2O3 nanocrystals with cubic (C-type) and monoclinic (B-type) crystalline structures have been studied. NCs have been synthetized by the sol-gel Pechini method and characterized at room temperature by X-ray diffraction, transmission electron microscopy, diffuse reflectance, Raman spectroscopy and photoluminescence techniques. NIR emission from Yb3+ ions has been observed in both C- and B-type NCs upon excitation of Eu3+ ions at 532 nm, where Yb3+ ions do not absorb photons. This fact reveals that an efficient non-resonant energy transfer process from Eu3+ to Yb3+ takes place, allowing to obtain simultaneous visible and NIR emissions under visible excitation. The decay curves of the 5D0 → 7F2 Eu3+ emission of C-type NCs corroborate this phenomenon since the Eu3+ lifetime has been found to decrease as the Yb3+ content increases. Finally, we discuss the use of the Eu3+ luminescence as a structural probe to distinguish between different RE2O3 polymorphs.M.T Candela would like to thank University of Cantabria for the pre-doctoral grant “Concepción Arenal”, co-financed by the Government of Cantabria. The authors acknowledge financial support from the European Union (FET Open project NCLas, ref. H2020-EU829161) and the Spanish Ministerio de Ciencia, Innovacion y Universidades (PGC2018–101464-B-I00)

    Performing simulated basic life support without seeing: blind vs. blindfolded people

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    Previous pilot experience has shown the ability of visually impaired and blind people (BP) to learn basic life support (BLS), but no studies have compared their abilities with blindfolded people (BFP) after participating in the same instructor-led, real-time feedback training. Twenty-nine BP and 30 BFP participated in this quasi-experimental trial. Training consisted of a 1 h theoretical and practical training session with an additional 30 min afterwards, led by nurses with prior experience in BLS training of various collectives. Quantitative quality of chest compressions (CC), AED use and BLS sequence were evaluated by means of a simulation scenario. BP’s median time to start CC was less than 35 s. Global and specific components of CC quality were similar between groups, except for compression rate (BFP: 123.4 + 15.2 vs. BP: 110.8 + 15.3 CC/min; p = 0.002). Mean compression depth was below the recommended target in both groups, and optimal CC depth was achieved by 27.6% of blind and 23.3% of blindfolded people (p = 0.288). Time to discharge was significantly longer in BFP than BP (86.0 + 24.9 vs. 66.0 + 27.0 s; p = 0.004). Thus, after an adapted and short training program, blind people were revealed to have abilities comparable to those of blindfolded people in learning and performing the BLS sequence and CCS

    A comparative study on luminescence properties of Y2O3: Pr3+ nanocrystals prepared by different synthesis methods

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    Pr3+-doped Y2O3 nanocrystals (NCs) have been obtained via five wet-chemistry synthesis methods which were optimized in order to achieve superior optical properties. To this end, a systematic study on the influence of different reaction parameters was performed for each procedure. Specifically, precursor concentration, reaction temperature, calcination temperature, and time, among others, were analyzed. The synthesized Y2O3: Pr3+ NCs were characterized by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), powder X-ray diffraction (PXRD), transmission electron microscopy (TEM), and reflectance and Raman spectroscopy. In addition, the optical properties of such NCs were investigated by excitation, emission, and luminescence decay measurements. Concretely, emission from the 1D2 level was detected in all samples, while emission from 3PJ was absent. Finally, the effect of the synthesis methods and the reaction conditions on the luminescence decay has been discussed, and a comparative study of the different methods using the fluorescence lifetime of so-obtained Y2O3: Pr3+ NCs as a figure of merit has been carried out.This work was funded with a Future and Emerging Technologies (FET) NCLas project; European Union; Proposal: 829161

    Effects of dietary restriction combined with different exercise programs or physical activity recommendations on blood lipids in overweight adults

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    Background and aim: Many exercise studies, although generally showing the beneficial effects of supervised aerobic, resistance or combined exercise on blood lipids, have sometimes reached equivocal conclusions. The aim of this study is to evaluate the impact of different programs that combined exercise and dietary restriction on blood lipids versus a clinical practice intervention for weight loss, in overweight adults. Methods: For this study 66 subjects participated in a supervised 22 weeks training program, composed of three sessions per week and they were randomized in three groups: strength training (S; n = 19), endurance training (E; n = 25), a combination of E and S (SE; n = 22). Eighteen subjects served as physical activity group (PA) that followed a clinical intervention consisted of physical activity recommendations. All groups followed the same dietary treatment, and blood samples were obtained for lipids measurements, at the beginning and end of the study. Results: Lipid profile improved in all groups. No significant differences for baseline and post-training values were observed between groups. In general, SE and PA decreased low-density lipoprotein cholesterol (LDL-C) values (p menor que 0.01). S decreased triglyceride levels (p menor que 0.01) and E, SE, and PA decreased total cholesterol levels (p menor que 0.05, p menor que 0.01 and p menor que 0.01, respectively). Conclusions: These results suggest that an intervention program of supervised exercise combined with diet restriction did not achieved further improvements in blood lipid profile than diet restriction and physical activity recommendations, in overweight adults. (Clinical Trials gov number: NCT01116856)

    Complete process of implantation of a nutritional risk screening system in the University Hospital La Paz, Madrid

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    La malnutrición asociada a la enfermedad (MAE) está presente en un porcentaje muy elevado de los pacientes que ingresan en los hospitales y su repercusión es diversa y de mucha trascendencia. Objetivo: Desde la Unidad de Nutrición del Hospital Universitario la Paz, en colaboración con todos los miembros de la Comisión de Nutrición, nos planteamos implantar algún método de cribado en nuestro centro, que permitiese abarcar al mayor número posible de pacientes. Resultados: Debido al gran tamaño de nuestro centro, con cerca de 1500 camas, unido a una escasez de recursos humanos en nuestra unidad, optamos por utilizar el sistema de cribado CONUT (Control Nutricional) 100% automático y basado en parámetros analíticos, muy fácil de manejar, de bajo coste y cuya validez está confirmada, adaptándolo a nuestras necesidades. El método recoge información de las bases de datos del servicio de Admisión (filiación, edad, fecha) y del Laboratorio (albúmina, colesterol, linfocitos totales) y genera, en el informe de resultados de los análisis clínicos, la información sobre la alerta de riesgo nutricional de cada paciente, así como las recomendaciones nutricionales a seguir en función del riesgo detectado en cada caso. Para llegar su implantación se llevaron a cabo diferentes evaluaciones que nos permitieron conocer previamente la carga extra de trabajo que podría generar su implantación y nuestra capacidad para asumirlas, así como numerosas actividades formativas encaminadas a que los médicos y profesionales sanitarios del hospital asumieran cada vez más responsabilidades en el proceso del tratamiento nutricional de sus pacientes. Este sistema de cribado funciona desde Junio del año 2010 y detecta riesgo de desnutrición en el 32% de los pacientes evaluados. En general, sólo en los casos en los que la alerta corresponde a una situación de Alto riesgo nutricional, hecho que se da aproximadamente en el 10% del total, se requirió la intervención especializada por parte de la Unidad de Nutrición Clínica y Dietética. Posteriormente, conforme hemos ido detectando posibles causas que justificaran que el sistema no funcionase adecuadamente, el sistema de cribado ha sido objeto de diversas modificaciones. En este sentido, se ha realizado una evaluación retrospectiva en 233 pacientes ingresados en las plantas de Cirugía General y se ha documentado que aquellos que ingresan para cirugía programada y presentan una alarma alta o moderada de desnutrición (el 50% de los casos), la presencia de la misma aumenta significativamente los días de ingreso y la mortalidad. Conclusiones: La implantación del cribado nutricional ha favorecido un cambio en la cultura de nuestro centro con respecto a la malnutrición asociada a la enfermedad y la mayoría de nuestros profesionales, tanto médicos como enfermeras e incluso el equipo directivo, comprenden la importancia del proceso y saben que disponemos de herramientas y de conocimiento suficiente para indicar un soporte nutricional adecuado y precozDisease-Related Malnutrition (DRM) is present in a high percentage of patients admitted to hospital and their impact is diverse and of great importance. Objectives: Nutrition Department of University Hospital La Paz, in collaboration with all members of the Nutrition Committee, we decided to implement some method of screening in our centre which allowed us to detect as many patients with malnutrition risk as possible. Results: Due to the large size of our centre, with about 1,500 beds and the few human resources in our unit, we chose to use the CONUT system (Nutritional Control), a 100% automatic method based on analytical parameters, very easy to use, low cost and whose validity is confirmed, characteristics that fulfilled our needs. The method collects information from databases of Admission Service (affiliation, age, date) and Laboratory (albumin, cholesterol, total lymphocytes) and generates, in the report of analytical results, “alert” information about each patient’s nutritional risk and also nutritional recommendations based on the risk identified. Prior to its implantation several evaluations were performed in order to allow us to better know the extra workload, as it was the main factor that could limit our ability to assume that screening method and also many training activities for doctors and hospital health professionals who were increasingly assuming responsibilities in the nutritional treatment of their patients. This screening system has been working from june of 2010 and it has detected risk of malnutrition in 32% of the evaluated patients. In general, only in those cases where the alert corresponded to a high-risk nutritional situation, which represents approximately 10% of the total, specialized intervention by the Clinical Nutrition Unit was required. Later, as we have detected some possible causes that justify the system does not work properly; the screening system has undergone several changes . In this sense, we have made a retrospective evaluation of 233 patients admitted to the General Surgery plants and documented that those entering for scheduled surgery, having a alarm of malnutrition (50% of cases), its presence increases significantly the hospital stay and mortality. Conclusions: The implementation of this nutritional screening method has led to a change in the ìnutritionalî culture of our centre respect to DRM in most of our professionals: doctors and nurses and even in the management team, so all of them understand the importance of the process and know about the available tools and knowledge to indicate an adequate and early nutritional suppor

    Identification of ABA-Mediated Genetic and Metabolic Responses to Soil Flooding in Tomato (Solanum lycopersicum L. Mill)

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    [EN] Soil flooding is a compound abiotic stress that alters soil properties and limits atmospheric gas diffusion (O-2 and CO2) to the roots. The involvement of abscisic acid (ABA) in the regulation of soil flooding-specific genetic and metabolic responses has been scarcely studied despite its key importance as regulator in other abiotic stress conditions. To attain this objective, wild type and ABA-deficient tomatoes were subjected to short-term (24 h) soil waterlogging. After this period, gas exchange parameters were reduced in the wild type but not in ABA-deficient plants that always had higher E and g(s). Transcript and metabolite alterations were more intense in waterlogged tissues, with genotype-specific variations. Waterlogging reduced the ABA levels in the roots while inducing PYR/PYL/RCAR ABA receptors and ABA-dependent transcription factor transcripts, of which induction was less pronounced in the ABA-deficient genotype. Ethylene/O-2-dependent genetic responses (ERFVIIs, plant anoxia survival responses, and genes involved in the N-degron pathway) were induced in hypoxic tissues independently of the genotype. Interestingly, genes encoding a nitrate reductase and a phytoglobin involved in NO biosynthesis and scavenging and ERFVII stability were induced in waterlogged tissues, but to a lower extent in ABA-deficient tomato. At the metabolic level, flooding-induced accumulation of Ala was enhanced in ABA-deficient lines following a differential accumulation of Glu and Asp in both hypoxic and aerated tissues, supporting their involvement as sources of oxalacetate to feed the tricarboxylic acid cycle in waterlogged tissues and constituting a potential advantage upon long periods of soil waterlogging. The promoter analysis of upregulated genes indicated that the production of oxalacetate from Asp via Asp oxidase, energy processes such as acetyl-CoA, ATP, and starch biosynthesis, and the lignification process were likely subjected to ABA regulation. Taken together, these data indicate that ABA depletion in waterlogged tissues acts as a positive signal, inducing several specific genetic and metabolic responses to soil flooding.This work was supported by the Spanish Ministerio de Economia y Competitividad, Universitat Jaume I and Generalitat Valenciana/Fondo Europeo de Desarrollo Regional (FEDER), co-funded through grant nos. AGL2016-76574-R, UJI-B201623, UJI-B2016-24, IDIFEDER/2018/010, and UJI-B2019-24 to AG-C, VA, and MG-G, respectively. CD was supported by UJI PICD program. MG-G and JM were supported by Ramon y Cajal contracts from Spanish Ministerio de Economia y Competitividad (RYC-2016-19325 and RYC-201723645, respectively). JR was supported by a Juan de la CiervaFormacion contract from the Spanish Ministerio de Economia y Competitividad (FJCI-2016-28601).De Ollas, C.; González-Guzmán, M.; Pitarch, Z.; Matus, JT.; Candela, H.; Rambla Nebot, JL.; Granell Richart, A.... (2021). Identification of ABA-Mediated Genetic and Metabolic Responses to Soil Flooding in Tomato (Solanum lycopersicum L. Mill). Frontiers in Plant Science. 12:1-20. https://doi.org/10.3389/fpls.2021.613059S1201

    Influence of ADRB2 Gln27Glu and ADRB3 Trp64Arg polymorphisms on body weight and body composition changes after a controlled weight-loss intervention

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    The ?-2 and ?-3 adrenergic receptors (ADRB2 and ADRB3) are thought to play a role in energy expenditure and lipolysis. However, the effects of the ADRB2 glutamine (Gln) 27 glutamic acid (glutamate) (Glu) and ADRB3 tryptophan (Trp) 64 arginine (Arg) polymorphisms on weight loss remain controversial. The aim of this study was to investigate the effect of these polymorphisms on changes in weight and body composition during a controlled weight-loss program. One hundred seventy-three healthy overweight and obese participants (91 women, 82 men) aged 18?50 years participated in a 22-week-long intervention based on a hypocaloric diet and exercise. They were randomly assigned to 1 of 4 groups: strength, endurance, strength and endurance combined, and physical activity recommendations only. Body weight, body mass index (BMI), and body composition variables were assessed before and after the intervention. Genetic analysis was carried out according to standard protocols. No effect of the ADRB2 gene was shown on final weight, BMI, or body composition, although in the supervised male group, Glu27 carriers tended to have greater weight (p = 0.019, 2.5 kg) and BMI (p = 0.019, 0.88 kg/m2) reductions than did noncarriers. There seems to be an individual effect of the ADRB3 polymorphism on fat mass (p = 0.004) and fat percentage (p = 0.036), in addition to an interaction with exercise for fat mass (p = 0.038). After the intervention, carriers of the Arg64 allele had a greater fat mass and fat percentage than did noncarriers (p = 0.004, 2.8 kg). In conclusion, the ADRB2 Gln27Glu and ADRB3 Trp64Arg polymorphisms may influence weight loss and body composition, although the current evidence is weak; however, further studies are necessary to clarify their roles

    Strength plus Endurance Training and Individualized Diet Reduce Fat Mass in Overweight Subjects:A Randomized Clinical Trial

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    Studies with overweight people are a priority in order to observe the effect of the timing of intervention on pre-obesity people. The aim was to compare different physical activity programs plus an individualized hypocaloric diet on body composition in overweight subjects. A randomized controlled clinical trial was carried out in overweight adults with no history of relevant illness. Primary outcome was total fat mass (TFM). Participants were allocated into four activity programs with equal intensity and volume of exercise for 22 weeks: strength training (S), endurance training (E), strength + endurance training (SE), and 'adhering to physical activity recommendations' (C). Participants followed a diet with 25% less energy (50%-55% carbohydrates, 30%-35% fat) measured by accelerometer. Variables were assessed at baseline and at the end of the intervention. Body composition was measured by dual-energy X-ray absorptiometry. One hundred nineteen from 205 subjects were randomized in the four exercise groups (S = 30/E = 30/SE = 30/C = 29) and 84 participants (36 men/48 women) ended the intervention (S = 19/E = 25/SE = 22/C = 18). At the end of the experiment, all groups except C increased their total physical activity (S = 1159 ± 1740; E = 1625 ± 1790; SE = 1699 ± 2516; C = 724 ± 1979 MET-min/week). Using an ANOVA-test, improvements were observed in body weight (S = -4.6 ± 4.5; E = -6.6 ± 4.6; SE = -8.5 ± 2.8; C = -6.1 ± 5.6 kg, p = 0.059) and TFM (S = -4.24 ± 2.02; E = -4.74 ± 2.96; SE = -6.74 ± 3.27; C = -3.94 ± 4.18%; p < 0.05). The main conclusion was that there were no adverse events. Strength and endurance training with a balanced, individualized hypocaloric diet was the most effective at reducing weight loss and fat mass in overweight subjects. Trial registration: NCT01116856

    The medieval town of Handoga (Djibouti): A report of the 2021 field season

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    The article presents the results of the first campaign carried out at the medieval site of Handoga (Djibouti) by the StateHorn project, based at the Institute of Heritage Sciences of the Spanish National Research Council. The aim of the campaign was to assess the site's potential in order to launch a long-term project focusing on the study of the town's urbanism and way of life. The campaign included a systematic survey of the site and the excavation of four test pits, which revealed evidence for two archaeological phases at Handoga. The results of the campaign suggest that Handoga was an important urban centre on the medieval routes linking the Gulf of Tadjoura with the interior of Africa, of which very little is known
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