3,358 research outputs found

    Diversity and conservation of the Gredos Regional Park peatlands (Iberian Central System, Spain): Geomorphological and geobotanical characterisation and incoming threats

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    High-mountain peatlands are essential ecosystems for habitats, biodiversity, water, and carbon cycling, but there is little comprehensive information in central Iberia. We present results of research concerning the distribution, geormorphology, floristic, geobotany, and habitat diversity of peatlands in the Gredos Regional Park (Iberian Central System). We identified 72 peatlands covering 117 ha and ranging in size from 0.01 to 17.34 ha. Peatlands occur primarily in the upper orosubmediterranean bioclimatic belt at 1775–2230 m asl. From a geomorphological point of view, 9 different peatland typologies have been defined. Multivariate analyses (agglomerative cluster analysis and principal component analysis) of 103 relevés allowed us to classify the sampled peatland stands into 7 plant communities and 4 European habitats that formed along complex hydrogeomorphic conditions, and to propose a new subassociation of other community previously described (Caricetum echinato-nigrae lycopodielletosum inundatae). The main threat to Gredensean peatlands is pastoral pressure, which affects 15 of them intensively, mainly between the upper supramediterranean and the lower orosubmediterranean bioclimatic belts (~1314–1700 m asl). Seven bryophytes and three vascular plants documented in the Gredos Regional Park peatlands are included in the IUCN Red List. From the point of view of conservation priority, the most threatened correspond to transition mires communities (Habitat 7140) growing in oligotrophic and minerotrophic peatlands (Caricion nigrae vegetation). Particularly, the Iberian Central System endemic Sedo lagascae-Eriophoretum latifolii association is the one that has achieved the highest score in the five criteria considered in this regard because Meesia triquetra, a species with the category of “critically endangered”, inhabits it

    Prevalence and psychosocial risk factors of depression in a group of older adults in Bogota

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    prevalencia se ha descrito entre 1,2 a 12% en mayores que viven en comunidad. Objetivo: estimar la prevalencia de depresión en un muestra de adultos mayores de Bogotá y describir los factores de riesgo psicosocial asociados. Material y métodos: se realizó un estudio de corte transversal observacional-descriptivo, en 889 adultos mayores autónomos. La depresión fue evaluada con el test de depresión geriátrica Yesavage y los factores de riesgo con la sección de acontecimientos vitales del cuestionario Predict. Resultados: el 74% de la muestra estuvo constituida por mujeres, la media de edad fue de 72,51 (DS 9,4) años y la escolaridad promedio en años fue de 7,50 (DS 5,64). Así mismo, se estimó una prevalencia de depresión del 18,6%, siendo mayor en mujeres (20%) y (18%) en sujetos entre 70 y 79 años, los adultos con baja escolaridad sumaron un 43%, y el 22% lo constituyeron personas dependientes económicamente. Por otra parte, se encontró relación entre la depresión y cinco de los factores de riesgo psicosocial conocidos como acontecimientos vitales adversos: insomnio, vivir solo, padecer enfermedades crónicas, haber sufrido una crisis económica, y la muerte de un familiar o amigo cercano en el último año. Conclusión: la prevalencia de depresión en un grupo de personas mayores de la comunidad en Bogotá es más alta que lo descrito previamente en Colombia y por la Organización Mundial de la Salud (OMS). Programas que reduzcan la soledad en la vejez y protejan a la mujer y a los mayores con menos escolaridad podrían mitigar esta condición.Introduction: depression is one of the most prevalent diseases in the elderly. In Colombia, the prevalence of depression in this population ranges from 1,2 to 12%. Objective: to estimate the prevalence of depression in a group of independent elderly subjects in Bogota and describe the psychosocial risk factors associated with it. Material and methods: a cross-observational and descriptive study was done. The sample was constituted of 889 autonomous elderly subjects of Bogota city. Depression was assessed by applying the Test of Geriatric Depression-Yesavage-. Besides, the psychosocial risk factors were measured through the life events section, which is part of the Predict Questionnaire. Results: 74% of the sample was made up of women, the mean age was 72,51 years old (DS.9,4) and the average of education was of 7.50 years (DS.5,64). Besides, it was found a prevalence of depression of 18,6%. This prevalence was higher in the women (20%) and elderly between 70 and 79 years old (18%), adults with low education with 43% or 22% in economically dependent people. A relationship between depression and five psychosocial risk factors, known as adverse life events-insomnia, living alone, suffering a chronic disease or economic crisis or the death of the couple, a close friend or a relative. Conclusion: results showed a higher prevalence of depression in this sample in comparison to the findings yielded in previous studies developed in Colombia and the WHO. Programs that help to reduce the long lines protect women and older with less schooling ageing could mitigate the condition

    Palaeoenvironmental changes in the Iberian central system during the Late-glacial and Holocene as inferred from geochemical data: A case study of the Navamuño depression in western Spain

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    The Iberian Central System (ICS) is a clue region to reveal Mediterranean/Atlantic inferences over Iberia. We present a multidisciplinary study from western Spain conducted in the Navamuno ˜ depression (ND), covering the last 16.8 ka (cal BP). A reconstruction of the palaeotemperature from the resulting geochemical data highlights four cold and dry intervals, namely, the Oldest Dryas, Older Dryas, Intra-Allerød Cold Period (IACP), and the Younger Dryas, along with warmer intervals: the Bølling (14.7–14 ka) and the Allerød (12.9–12.6 ka); however, the Greenland Interstadial GI-1c (13.4–13.1 ka) is barely distinguishable in the ND. Despite the shortage of biomass to sustain fire, the earliest charcoals are from ~14.4–13.8 ka. Evidence of ash/dust events overprinting the geochemical background starts at ~13.8–12.8 ka. Significant fire activity in the Early Holocene at ~11.7–10.6 ka affected the ND, matching the westernmost ICS data. This period includes short oceanic spells inferred from Cl peaks at ~10.9–10.2 ka and three cold intervals at 11.4, 9.3, and 8.2 ka disrupted the progressive temperature increase. The Mid-Holocene showed a continuously increasing trend towards an arid climate, peaking at 4.2 ka under a pervasive dust influx from North Africa, which has prevailed since almost ~7.9 ka. A prominent volcanic event at ~6.8–5.8 ka is in Navamuno ˜ and Ronanzas ˜ (Asturias, N Spain; Gallego et al., 2013) identified from heavy metal-rich layer, synchronous with the last known eruption of the Calatrava volcanic field (South-Central Spain; Poblete-Piedrabuena et al., 2019). This volcanic eruption could affect many other regions half north of Iberia. The pervasive presence of oceanic aerosols in the last three millennia (2.8 ka ~ ) allowed the formation of a Cl-rich peat layer during the Ibero-Roman humid period ~2.1 ka, before a changing around ~0.4 ka toward colder and drier conditions at the Little Ice Age (LIA) periodThis study was funded by the LATESICE-CGL2016-78380-P, FINICES- PID2020-117685 GB-I00 and MED-REFUGIA-RTI2018-101714-BI00 (Plan Nacional I + D + I, Spanish Ministry of Science, Innovation and Universities) projects

    First narrow-band search for continuous gravitational waves from known pulsars in advanced detector data

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    Spinning neutron stars asymmetric with respect to their rotation axis are potential sources of continuous gravitational waves for ground-based interferometric detectors. In the case of known pulsars a fully coherent search, based on matched filtering, which uses the position and rotational parameters obtained from electromagnetic observations, can be carried out. Matched filtering maximizes the signalto- noise (SNR) ratio, but a large sensitivity loss is expected in case of even a very small mismatch between the assumed and the true signal parameters. For this reason, narrow-band analysis methods have been developed, allowing a fully coherent search for gravitational waves from known pulsars over a fraction of a hertz and several spin-down values. In this paper we describe a narrow-band search of 11 pulsars using data from Advanced LIGO’s first observing run. Although we have found several initial outliers, further studies show no significant evidence for the presence of a gravitational wave signal. Finally, we have placed upper limits on the signal strain amplitude lower than the spin-down limit for 5 of the 11 targets over the bands searched; in the case of J1813-1749 the spin-down limit has been beaten for the first time. For an additional 3 targets, the median upper limit across the search bands is below the spin-down limit. This is the most sensitive narrow-band search for continuous gravitational waves carried out so far

    Constraints on the χ_(c1) versus χ_(c2) polarizations in proton-proton collisions at √s = 8 TeV

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    The polarizations of promptly produced χ_(c1) and χ_(c2) mesons are studied using data collected by the CMS experiment at the LHC, in proton-proton collisions at √s=8  TeV. The χ_c states are reconstructed via their radiative decays χ_c → J/ψγ, with the photons being measured through conversions to e⁺e⁻, which allows the two states to be well resolved. The polarizations are measured in the helicity frame, through the analysis of the χ_(c2) to χ_(c1) yield ratio as a function of the polar or azimuthal angle of the positive muon emitted in the J/ψ → μ⁺μ⁻ decay, in three bins of J/ψ transverse momentum. While no differences are seen between the two states in terms of azimuthal decay angle distributions, they are observed to have significantly different polar anisotropies. The measurement favors a scenario where at least one of the two states is strongly polarized along the helicity quantization axis, in agreement with nonrelativistic quantum chromodynamics predictions. This is the first measurement of significantly polarized quarkonia produced at high transverse momentum

    High voltage calibration method for the CMS RPC detector

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    The Resistive Plate Chambers (RPC) are used for muon triggers in the CMS experiment. To calibrate the high voltage working-points (WP) and identify degraded detectors due to radiation or chemical damage, a high voltage scan has been performed using 2017 data from pp collisions at a center-of-mass energy of 13 TeV. In this paper, we present the calibration method and the latest results obtained for the 2017 data. A comparison with all scans taken since 2011 is considered to investigate the stability of the detector performance in time
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