68 research outputs found

    Influence of Partial Soil Wetting on Water Relation Parameters of the Olive Tree

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    A drip versus pond irrigation experiment was carried out with 30-year-old ‘Manzanilla’ olive trees planted at 7 m 5 m in an orchard in Southwest Spain. At the end of the dry season of 1998, we chose two dry-land trees, D1 and D2, and two drip-irrigated trees, I1 and I2. During the experiments, the D1 and I1 trees were pond-irrigated, increasing the soil water content to around field capacity in the whole rootzone. The D2 and I2 trees were drip-irrigated, remaining part of the rootzone in drying soil. The results showed that the ratio between the transpiration of the pond-irrigated D1 tree and that of the drip-irrigated D2 tree (D1/D2 Ep) increased from an average of 0.88 before irrigation to 1.22 fourteen days after the first water supply. For the I trees, I1/I2 Ep varied from 0.76 to 1.02 nine days after the I1 tree was pond-irrigated for the first time. Transpiration, therefore, was restricted when using a drip irrigation system which, despite supplying enough water to cover the calculated crop demand, affected a part of the rootzone only. During the drip versus pond irrigation experiment, the recovery of leaf water potential, stomatal conductance and photosynthesis rate was greater and quicker in the pond-irrigated than in the drip-irrigated trees.– Influence de l’irrigation partielle du sol sur les paramètres des relations hydriques de l’olivier. Une comparaison de l’irrigation goutte à goutte avec l’irrigation en cuvette a été conduite sur oliviers ‘Manzanilla’ âgés de 30 ans plantés à 7 m 5 m dans un verger du sud-ouest de l’Espagne. À la fin de la saison sèche de 1998, nous avons choisi deux arbres sur sol sec, D1 et D2, et deux arbres sur sol irrigué au goutte à goutte, I1 et I2. Durant les expériences, les arbres D1 et I1 ont été irrigués en cuvette, en augmentant la teneur en eau du sol jusqu’à la capacité au champ dans toute la zone racinaire. Les arbres D2 et I2 ont été irrigués au goutte à goutte, laissant une partie de la zone racinaire dans un sol se desséchant. Les résultats ont montré que le quotient entre la transpiration de l’arbre D1 irrigué en cuvette et celle de l’arbre D2 irrigué au goutte à goutte (D1/D2 Ep) a augmenté à partir d’une moyenne de 0,88 avant irrigation jusqu’à 1,22 quatorze jours après le premier apport d’eau. Pour les arbres I, I1/I2 Ep a varié entre 0,76 et 1,02 neuf jours après que l’arbre I1 ait été irrigué en cuvette pour la première fois. Par conséquent, la transpiration était réduite quand on utilisait un système d’irrigation au goutte à goutte qui, malgré l’apport d’eau suffisant pour couvrir les besoins potentiels des cultures, a affecté seulement une partie de la zone racinaire. Durant cette comparaison de l’irrigation goutte à goutte et de l’irrigation en cuvette, la récupération de la teneur en eau des feuilles, de la conductance stomatique et du taux de photosynthèse était supérieure et plus rapide pour les arbres irrigués en cuvette que pour ceux irrigués au goutte à goutte

    Canopy architecture and radiation interception measurements in olive

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    In this work we tested techniques suitable for a future validation of the RATP model to simulate transpiration and photosynthesis of mature olive trees under field conditions. Canopy architecture was characterised with an electromagnetic 3D digitiser and the software 3A. Although the capability of the software to deal with big data sets has to be improved, the system seems to meet the RATP requirements. An array of radiation sensors mounted in an aluminium bar and located at different positions within the canopy showed to be an useful tool for monitoring radiation distribution; these data can be used to validate the RATP predictions. Leaves intercepting more radiation showed greater values both of area based nitrogen content and photosynthetic capacity, and the increment of nitrogen was found to be related to the increment in leaf mass area. A method was tested for assessing plant leaf area, which could allow us to determine the leaf area of the biggest trees in the orchard, with reduced time and labour.Ministerio de Ciencia y Tecnología AGL2002- 04048-CO3-0

    Inappropriate Hospital Admission According to Patient Intrinsic Risk Factors: an Epidemiological Approach

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    Background: Inappropriate hospital admissions compromise the efficiency of the health care system. This work analyzes, for the first time, the prevalence of inappropriate admission and its association with clinical and epidemiological patient characteristics. Objectives: To estimate the prevalence, associated risk factors, and economic impact of inappropriate hospital admissions. Design and Participants: This was a cross-sectional observational study of all hospitalized patients in a high complexity hospital of over 901 beds capacity in Spain. The prevalence of inappropriate admission and its causes, the association of inappropriateness with patients’ intrinsic risk factors (IRFs), and associated financial costs were analyzed with the Appropriateness Evaluation Protocol in a multivariate model. Main Measures and Key Results: A total of 593 patients were analyzed, and a prevalence of inappropriate admissions of 11.9% (95% CI: 9.5 to 14.9) was found. The highest number of IRFs for developing health care-related complications was associated with inappropriateness, which was more common among patients with 1 IRF (OR [95% CI]: 9.68 [3.6 to 26.2.] versus absence of IRFs) and among those with surgical admissions (OR [95% CI]: 1.89 [1.1 to 3.3] versus medical admissions). The prognosis of terminal disease reduced the risk (OR [95% CI]: 0.28 [0.1 to 0.9] versus a prognosis of full recovery based on baseline condition). Inappropriate admissions were responsible for 559 days of avoidable hospitalization, equivalent to €17,604.6 daily and €139,076.4 in total, mostly attributable to inappropriate emergency admissions (€96,805.3). Conclusions: The prevalence of inappropriate admissions is similar to the incidence found in previous studies and is a useful indicator in monitoring this kind of overuse. Patients with a moderate number of comorbidities were subject to a higher level of inappropriateness. Inappropriate admission had a substantial and avoidable financial impact

    Evidences of the Blake and Iceland Basin magnetic excursions in southeastern Iberia and chronological implications for the Padul sedimentary record

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    Acknowledgments This study was supported by the project B-RNM-144-UGR18 and ARNM- 336-UGR20 of the action “Proyectos I + D + i del Programa Operativo FEDER 2018 - Junta de Andalucía-UGR”, the projects CGL2013-47038-R and CGL2017-85415-R, of the “Ministerio de Economía y Competitividad of Spain and Fondo Europeo de Desarrollo Regional FEDER”, and the research group RNM-190 (Junta de Andalucía), and the projects P18-RT-871 and Retos P20_00059 of Junta de Andalucia. A.G.-A. was also supported by a Ram´on y Cajal Fellowship RYC-2015-18966 of the Spanish Government (Ministerio de Economía y Competividad). A.L.-A PhD is funded by BES-2018-084293 (Ministerio de Economía y Competividad). We thank the Paleomagnetic Laboratory CCiTUB-Geo3Bcn CSIC for the support on paleomagnetic analysis. LV and EB thank the Geomodels Research Institute (UB). We are very grateful to two anonymous reviewers and to the editor Christian Zeeden.The Padul-15-05 sediment core provides an exceptional perspective of the paleoenvironmental and climate change in the Western Mediterranean region for the last ca. 200 kyr. However, even though a robust chronology mainly relying on radiometric dating is available for the last 50 ka, the chronology for the older sediments is not yet fully resolved. Ages for the bottom part of the core (>21 m) were previously inferred from amino-acid racemization dating and sediment accumulation rates. In this work, we provide a more accurate chronology for the older part (>100 kyr) of the Padul-15-05 sediment core record based on the recognition of past Earth's magnetic excursions. We identify an interval prone of reversed polarity samples close to MIS-5e/5 d transition that we correlate to the Blake geomagnetic excursion (116.5 kyr–112 kyr). In addition, we identify an interval of low inclinations and two reversed samples that we interpret as the Iceland Basin geomagnetic excursion (192.7 kyr–187.7 kyr: wide scenario of VGP <40°). Our new results, which include IRM acquisition curves that contribute to understand the magnetic mineralogy, enhances the robustness of the age model for the Padul-15-05 sedimentary sequence by adding an independent age dataset with new accurate tie-points. Our refined age control together with the available paleoenvironmental and paleoclimate multiproxy data provide insightful information to unveil the response of the western Mediterranean environments to regional environmental and climate change.Project B-RNM-144-UGR18 and ARNM- 336-UGR20 of the action “Proyectos I + D + i del Programa Operativo FEDER 2018 - Junta de Andalucía-UGR”Projects CGL2013-47038-R and CGL2017-85415-R, of the “Ministerio de Economía y Competitividad of Spain and Fondo Europeo de Desarrollo Regional FEDER”Research group RNM-190 (Junta de Andalucía)Projects P18-RT-871 and Retos P20_00059 of Junta de AndaluciaRamón y Cajal Fellowship RYC-2015-18966 of the Spanish Government (Ministerio de Economía y Competividad)Funded by BES-2018-084293 (Ministerio de Economía y Competividad

    Reconstruction of Past Environment and Climate Using Wetland Sediment Records from the Sierra Nevada

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    Understanding the effects of climate change and human activities on fragile mountain ecosystems is necessary to successfully managing these environments under future climate scenarios (e.g., global warming, enhanced aridity). This can be done through the study of paleoecological records, which can provide long paleoenvironmental databases containing information on how ecosystems reacted to climate change and human disturbances before the historical record. These studies can be particularly interesting when focusing on especially warm and/or dry past climatic phases. Biotic (pollen, charcoal) and abiotic (physical, geochemistry) analyses from wetland sediment records from the Sierra Nevada, southern Spain record changes in vegetation, fire history and lake sedimentation since ~11,700 years (cal yr BP). This multiproxy paleoecological study indicates that maxima in temperature and humidity occurred in the area in the Early and Middle Holocene, with a peak in precipitation between ~10,500 and 7000 cal yr BP. This is deduced by maxima in water runoff, the highest abundance of tree species and algae and high total organic carbon values recorded in the alpine wetland’s sedimentary records of the Sierra Nevada during that time period. In the last 7000 cal yr BP, and especially after a transition period between ~7000 and 5000 cal yr BP, a progressive aridification process took place, indicated by the decrease in tree species and the increase in xerophytic herbs in this region and a reduction in water runoff evidenced by the decrease in detritic input in the wetland sedimentary records. An increasing trend in Saharan dust deposition in the Sierra Nevada wetlands is also recorded through inorganic geochemical proxies, probably due to a coetaneous loss of vegetation cover in North Africa. The process of progressive aridification during the Middle and Late Holocene was interrupted by millennial-scale climatic oscillations and several periods of relative humid/droughty conditions and warm/cold periods have been identified in different temperature and/or precipitation proxies. Enhanced human impact has been observed in the Sierra Nevada in the last ~3000 cal yr BP through the increase in fires, grazing, cultivation, atmospheric pollution as well as reforestation by Pinus and the massive cultivation of Olea at lower altitudes.This study was supported by projects CGL2013-47038-R and CGL2017-85415-R funded by Ministerio de Economía y Competitividad of Spain and Fondo Europeo de Desarrollo Regional FEDER; Séneca Project 20788/PI/18; Junta de Andalucía I+D+i Junta de Andalucía 2020 Retos P-20-00059, FEDER Project B-RNM-144-UGR18, UGR-FEDER B-RNM-144-UGR18 Proyectos I + D + i del Programa Operativo FEDER 2018 and the research group RNM-190 (Junta de Andalucía). M.J.R.R. acknowledges the postdoctoral funding provided by the European Commission/H2020 (ERC-2017-ADG, project number 788616). J.C. acknowledges the postdoctoral funding provided by the Academy of Finland (project number 316702). A.G.-A. acknowledges the Ramón y Cajal fellowship RYC-2015-18966 provided by the Ministerio de Economía y Competitividad of the Spanish Government. M.R.G. acknowledges funding by the Juan de la Cierva-Incorporación program in the University of Granada (IJCI-2017-33755) from Secretaría de Estado de I+D+i, Spain. RSA acknowledges several travel grants from Northern Arizona University to support this work

    Millennial-scale cyclical environment and climate variability during the Holocene in the western Mediterranean region deduced from a new multi-proxy analysis from the Padul record (Sierra Nevada, Spain)

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    A high-resolution multi-proxy approach, integrating pollen, inorganic and organic geochemical and sedimentological analyses, has been carried out on the Holocene section of the Padul sedimentary record in the southern Iberian Peninsula reconstructing vegetation, environment and climate throughout the last ~ 11.6 cal kyr BP in the western Mediterranean. The study of the entire Holocene allows us to determine the significant climate shift that occurred during the middle-to-late Holocene transition. The highest occurrence of deciduous forest in the Padul area from ~ 9.5 to 7.6 cal kyr BP represents the Holocene humidity optimum probably due to enhanced winter precipitation during a phase of highest seasonal anomaly and maximum summer insolation. Locally, insolation maxima induced high evaporation, counterbalancing the effect of relatively high precipitation, and triggered very low water table in Padul and the deposition of peat sediments. A transitional environmental change towards more regional aridity occurred from ~ 7.6 to 4.7 cal kyr BP and then aridification enhanced in the late Holocene most likely related to decreasing summer insolation. This translated into higher water levels and a sedimentary change at ~ 4.7 cal kyr BP in the Padul wetland, probably related to reduced evaporation during summer in response to decreased in seasonality. Millennial-scale variability is superimposed on the Holocene long-term trends. The Mediterranean forest regional climate proxy studied here shows significant cold-arid events around ~ 9.6, 8.5, 7.5, 6.5 and 5.4 cal kyr BP with cyclical periodicities (~1100 and 2100 yr) during the early and middle Holocene. A change is observed in the periodicity of these cold-arid events towards ~1430 yr in the late Holocene, with forest declines around ~ 4.7–4, 2.7 and 1.3 cal kyr BP. The comparison between the Padul-15-05 data with published North Atlantic and Mediterranean paleoclimate records suggests common triggers for the observed climate variability, with the early and middle Holocene forest declines at least partially controlled by external forcing (i.e. solar activity) and the late Holocene variability associated with internal mechanisms (oceanic-atmospheric)

    Orbital-scale environmental and climatic changes recorded in a new ∼200,000-year-long multiproxy sedimentary record from Padul, southern Iberian Peninsula

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    Padul is one of the few wetland sites in southern Europe and the Mediterranean region that exhibits an unusually large temporal span (&gt;100 kyr) and continuous Quaternary sedimentary record. Previous core-based studies from Padul yielded paleoecological datasets (i.e., pollen and organic geochemistry), but with a poor age control that resulted in rather arbitrary climate inferences. Therefore, precise age control and a multidisciplinary approach is necessary to understand long-term regional environmental and climate change and the associated local response of the Padul wetland environment. Here we present a new long sediment record (Padul-15-05) from this wetland in the southern Iberian Peninsula with the aim of improving the age control of the sedimentary sequence and carrying out up-to-date high-resolution multiproxy analyses. In this study the age control is based on 61 AMS radiocarbon dates for the last ca. 50 kyr BP and on the extent of amino acid racemization (AAR) in mollusc shells extending back ∼118 kyr BP. No numerical ages are available for the bottom part of the core but the sediment accumulation rates (SAR) and the cyclostratigraphic analysis of the multiproxy data suggest that the core preserves a continuous record of the last ∼197 kyr (from late MIS 7 to present) with millennial-scale time resolution. Sedimentological (lithology, magnetic susceptibility, XRD, color), geochemical (XRF, TOC, C/N, % carbonate content) and paleontological (pollen, charophytes, gastropods) data show co-varying cyclical paleoenvironmental changes linked to orbital-scale climatic variability. Silicon, magnetic susceptibility (MS) and total organic carbon (TOC) data show periodicities between ∼26.2–19.6 kyr linked to insolation, which is strongly dominated by precession cycles at this latitude. High values of Si and MS data have been related to high siliciclastic/detrital input from Sierra Nevada range during minima in insolation due to enhanced soil weathering/erosion during regional aridity and lower forest cover recorded by the arboreal pollen, which could also be favored by a minor biogenic productivity. In addition, warm climate conditions during maxima in insolation mostly resulted in negative precipitation/evapotranspiration balance and low lake levels, while cold glacial and stadial periods were mainly characterized by positive precipitation/evapotranspiration balance, and therefore, high lake levels. The improved chronology of the Padul sedimentary sequence along with a multiproxy study permitted us to better relate environmental and vegetation changes to climatic events and to demonstrate how both local (i.e., lake level, sedimentation) and regional (i.e., vegetation) environments responded to orbital-scale climate changes

    Challenge 1: Past global changes: a context to the Anthropocene

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    Facing current climate and environmental crises needs long-term series of Earth Dynamics and anthropogenic pressures on the Planet. Numerous geological, chemical and biological natural archives capture large-scale, multi-temporal, abrupt, and often irreversible shifts in environmental and climate systems, providing an opportunity to better understand and therefore predict potential future impacts of the present anthropogenic warming and Humankind impact on the Planet. By providing robust, reliable, quantitative, detailed, high-resolution and long paleoclimate and paleoenvironmental data series, paleoclimatology and paleoenvironmental research place present climate variability and ecological crises in a long-term perspective to understand climate forcing mechanisms and environmental processes and responses. The success of science-based solutions to the global risks in the 21st century will strongly rely on our capacity to transfer this knowledge to politicians, managers, and society.Peer reviewe

    Efecto del Allium sativum sobre la eficacia de metformina en Rattus norvegicus con Diabetes Mellitus

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    Objetivo: Evaluar el efecto del extracto de Allium sativum L. sobre la eficacia del tratamiento con metformina en Rattus norvegicus cepa Holtzman con diabetes mellitus inducida por aloxano. Material y métodos: Se realizó un estudio experimental aleatorizado, donde se utilizaron 48 ratas Holtzman y aloxano como inductor de diabetes mellitus. Los especímenes fueron distribuidos en cuatro grupos: Grupo 0 (G0): Sin ningún tratamiento (control); Grupo 1 (G1): extracto de Allium sativum L. 500 mg / kg; Grupo 2 (G2): metformina 100 mg/kg; Grupo 3 (G3): Extracto de Allium sativum L. 500 mg/kg más metformina 100 mg/kg. Las sustancias fueron administradas vía oral durante veintiocho días consecutivos, en los que se obtuvieron muestras sanguíneas mediante glucometría. Resultados: Se encontró una diferencia estadísticamente significativa (p&lt;0,05) mediante la prueba ANOVA entre el grupo control (G0) y los grupos experimentales (G1, G2 y G3). La prueba de Duncan demostró una diferencia significativa entre los grupos G2 y G3 (p&lt;0,05). Conclusiones: El extracto de Allium sativum L.  tuvo un efecto potenciador sobre la metformina en Rattus norvegicus cepa Holtzman con Diabetes Mellitus inducida por aloxano. Palabras claves: Allium sativum, diabetes mellitus, metformina, glucemia. (Fuente: DeCS)DOI: http://dx.doi.org/10.17268/rmt.2019.v14i04.0

    Mountain strongholds for woody angiosperms during the Late Pleistocene in SE Iberia

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    Mediterranean mountains played an essential role during glacial periods as vegetation refugia. The SE Iberia Late Pleistocene woody angiosperm fossil and floristic evidences are reviewed in the context of phylogeographical studies aiming to identify (i) spatial patterns related to woody angiosperms glacial survival, (ii) structural and functional characteristics of montane refugia, and (iii) gaps in knowledge on the woody angiosperm patterns of survival in Mediterranean mountains. The distribution of palaeobotanical data for SE Iberia refugia has been found to be taphonomically biased due to the scarcity of available and/or studied high-altitude Late Pleistocene sites. However, Siles Lake data together with floristic inference provide evidences for woody angiosperms’ survival in a high-altitude Mediterranean area. The main features boosting survival at montane contexts are physiographic complexity and water availability. Phylogeography studies have mainly been conducted at a continental scale. Although they cohere with palaeobotanical data to a broad scale, a general lack of sampling of SE Iberian range-edge populations, as well as misconceptions about the origin of the populations sampled, impede to infer the proper location of woody angiosperms’ mountain refugia and their importance in the post-glacial European colonisation. We conclude that floristic, geobotanical, palaeobotanical, ethnographical and genetic evidence should be merged to gain a deeper understanding on the role played by Mediterranean mountains as glacial refugia in order to explain the current distribution of many plants and the large biodiversity levels encountered in Mediterranean mountain areas. This is hallmark for effective and efficient conservation and management
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