2,105 research outputs found
Stomatal control and hydraulic conductivity in 'Manzanilla' olive trees under different water regimes
Ministry of Education and Science (España) No.AGL2006-04666/AGREU, research project ref. STREP 02312
Influence of the soil water content and distribution on both the hydraulic and transpiration performance of 'Manzanilla' olive trees
VI International Symposium on Irrigation of Horticultural Crops, celebrado del 2-6 de noviembre de 2006 en Viña del Mar, Chile ISBN-978-90-66057-13-5This work was made with mature 'Manzanilla' olive trees in an orchard of a semi-arid area in southern Spain. Three water treatments were considered: Rainfed, in which the trees had rainfall as the only source of water supply; FAO, in which the trees were under localized irrigation to replace the crop water demand, with some roots left in drying soil; Pond, in which the whole rootzones of the trees were maintained under non-limiting soil water conditions for the whole dry season. Our aim was to obtain information on the mechanisms behind the reduction of transpiration (Ep) in the FAO trees, as compared to the Pond trees. Our results show a near-isohydric behaviour of the FAO trees, i.e. those trees under localized irrigation in which some roots are left in drying showed lower stomatal conductance than the Pond trees in which all roots were in wetted soil. This helped the FAO trees to maintain similar leaf water potentials than the Pond trees. In addition, the FAO trees maintained a constant difference between the water potential of the canopy and that in the soil. This has been described as an isohydrodynamic behaviour, and it is thought to be an improvement over a typically anisohydric behaviour. These mechanisms were behind the similar values of tree hydraulic conductance (K p) found in the FAO and Pond treatments. The Rainfed trees showed lower Kp values because of the low Ep values of those trees, due to the low soil water availability in that treatment. Our results show, however, that the Rainfed trees were able to maintain similar values of Kp all throughout the dry season, which shows that the hydraulic efficiency of the xylem of those trees was little affected by embolism, despite of the high demanding conditions in the area.Ministry of Education and Science (Spain) AGL2006-04666/AGRUnión Europea STREP 327 02312
Evaluación de las necesidades hídricas de tres variedades de fresas y de su respuesta frente a un recorte hídrico moderado
Instituto Nacional de Investigaciones RTA2012-00001-00-00FEDER CC10-009-C02-0
Using a process-based stomatal model in olive and its potential application to deficit irrigation studies
Over the last years modeling plant transpiration has been pointed out as a powerful tool to
optimize the management of irrigation in fruit trees. In this study we tested the
hydromechanical model of stomata functioning proposed by Buckley et al. (2003), a model
with a strong physiological basis. The great contribution of this model is that its parameters
have direct physiological meaning. Firstly, the model was simplified to make its parameters
estimation friendly and easy. Secondly, the model was fitted to data obtained in a hedgerow
olive orchard under regulated deficit irrigation. The hydromechanical model fitted our data
satisfactorily and allowed us to analyze the physiological parameters obtained.Ministerio de Ciencia e Innovación español AGL2009-11310/AGRJunta de Andalucí
Four chamber right ventricular longitudinal strain versus right free wall longitudinal strain. Prognostic value in patients with left heart disease
Background: There is no consensus on which right ventricle (RV) strain parameter should be used in the clinical practice: four chamber RV longitudinal strain (4CH RV-LS) or free wall longitudinal strain (FWLS). The aim of this study was to analyze which RV strain parameter better predicts prognosis in patients with left heart disease.
Methods: One hundred and three outpatients with several degrees of functional tricuspid regurgitation severity secondary to left heart disease were prospectively included. 4CH RV-LS and FWLS were assessed using speckle tracking. Left ventricular (LV) systolic function was determined using LV ejection fraction and RV systolic function using tricuspid annular plane systolic excursion (TAPSE). Patients were followed up for 23.1 ± 12.4 months for an endpoint of cardiac hospitalization due to heart failure.
Results: The cutoff value related to RV dysfunction (TAPSE < 17 mm) was lower, in absolute value, for 4CH RV-LS (4CH RV-LS = –17.3%; FWLS = –19.5%). There were 33 adverse events during the follow-up. Patients with 4CH RV-LS > –17.3% (log rank [LR] = 22.033; p < 0.001); FWLS > –19.5% (LR = 12.2; p < 0.001), TAPSE < 17 mm (LR = 17.4; p < 0.001) and LV systolic dysfunction (LR = 13.3; p < 0.001) had lower event-free survival (Kaplan Meier). In Cox multivariate analysis, 4CH RV-LS > –17.3% (hazard ratio [HR] = 3.593; p < 0.002), TAPSE < 17 (HR = 2.093; p < 0.055) and LV systolic dysfunction (HR = 2.087; p < 0,054) had prognostic value, whereas FWLS did not reach significance.
Conclusions: Although both 4CH RV-LS and FWLS have prognostic value, 4CH RV-LS is a better predictor of episodes of heart failure in patients with left heart disease, providing additional information to that obtained by TAPSE.
Psychometric characteristics of the Spanish version of instruments to measure neck pain disability
[EN] Background. The NDI, COM and NPQ are evaluation instruments for disability due to NP. There was no Spanish version of NDI or COM for which psychometric characteristics were known. The objectives of this study were to translate and culturally adapt the Spanish version of the Neck Disability Index Questionnaire (NDI), and the Core Outcome Measure (COM), to validate its use in Spanish speaking patients with non-specific neck pain (NP), and to compare their psychometric characteristics with those of the Spanish version of the Northwick Pain Questionnaire (NPQ). Methods. Translation/re-translation of the English versions of the NDI and the COM was done blindly and independently by a multidisciplinary team. The study was done in 9 primary care Centers and 12 specialty services from 9 regions in Spain, with 221 acute, subacute and chronic patients who visited their physician for NP: 54 in the pilot phase and 167 in the validation phase. Neck pain (VAS), referred pain (VAS), disability (NDI, COM and NPQ), catastrophizing (CSQ) and quality of life (SF-12) were measured on their first visit and 14 days later. Patients' self-assessment was used as the external criterion for pain and disability. In the pilot phase, patients' understanding of each item in the NDI and COM was assessed, and on day 1 test-retest reliability was estimated by giving a second NDI and COM in which the name of the questionnaires and the order of the items had been changed. Results. Comprehensibility of NDI and COM were good. Minutes needed to fill out the questionnaires [median, (P25, P75)]: NDI. 4 (2.2, 10.0), COM: 2.1 (1.0, 4.9). Reliability: [ICC, (95%CI)]: NDI: 0.88 (0.80, 0.93). COM: 0.85 (0.75,0.91). Sensitivity to change: Effect size for patients having worsened, not changed and improved between days 1 and 15, according to the external criterion for disability: NDI: -0.24, 0.15, 0.66; NPQ: -0.14, 0.06, 0.67; COM: 0.05, 0.19, 0.92. Validity: Results of NDI, NPQ and COM were consistent with the external criterion for disability, whereas only those from NDI were consistent with the one for pain. Correlations with VAS, CSQ and SF-12 were similar for NDI and NPQ (absolute values between 0.36 and 0.50 on day 1, between 0.38 and 0.70 on day 15), and slightly lower for COM (between 0.36 and 0.48 on day 1, and between 0.33 and 0.61 on day 15). Correlation between NDI and NPQ: r = 0.84 on day 1, r = 0.91 on day 15. Correlation between COM and NPQ: r = 0.63 on day 1, r = 0.71 on day 15. Conclusion. Although most psychometric characteristics of NDI, NPQ and COM are similar, those from the latter one are worse and its use may lead to patients' evolution seeming more positive than it actually is. NDI seems to be the best instrument for measuring NP-related disability, since its results are the most consistent with patient's assessment of their own clinical status and evolution. It takes two more minutes to answer the NDI than to answer the COM, but it can be reliably filled out by the patient without assistanceS
Psychometric characteristics of the Spanish version of instruments to measure neck pain disability
Background: The NDI, COM and NPQ are evaluation instruments for disability due to NP. There was no Spanish version of NDI or COM for which psychometric characteristics were known. The objectives of this study were to translate and culturally adapt the Spanish version of the Neck Disability Index Questionnaire (NDI), and the Core Outcome Measure (COM), to validate its use in Spanish speaking patients with non-specific neck pain (NP), and to compare their psychometric characteristics with those of the Spanish version of the Northwick Pain Questionnaire (NPQ).
Methods: Translation/re-translation of the English versions of the NDI and the COM was done blindly and independently by a multidisciplinary team. The study was done in 9 primary care Centers and 12 specialty services from 9 regions in Spain, with 221 acute, subacute and chronic patients who visited their physician for NP: 54 in the pilot phase and 167 in the validation phase. Neck pain (VAS), referred pain (VAS), disability (NDI, COM and NPQ), catastrophizing (CSQ) and quality of life (SF-12) were measured on their first visit and 14 days later. Patients' self-assessment was used as the external criterion for pain and disability. In the pilot phase, patients' understanding of each item in the NDI and COM was assessed, and on day 1 test-retest reliability was estimated by giving a second NDI and COM in which the name of the questionnaires and the order of the items had been changed.
Results: Comprehensibility of NDI and COM were good. Minutes needed to fill out the questionnaires [median, (P25, P75)]: NDI. 4 (2.2, 10.0), COM: 2.1 (1.0, 4.9). Reliability: [ICC, (95%CI)]: NDI: 0.88 (0.80, 0.93). COM: 0.85 (0.75,0.91). Sensitivity to change: Effect size for patients having worsened, not changed and improved between days 1 and 15, according to the external criterion for disability: NDI: -0.24, 0.15, 0.66; NPQ: -0.14, 0.06, 0.67; COM: 0.05, 0.19, 0.92. Validity: Results of NDI, NPQ and COM were consistent with the external criterion for disability, whereas only those from NDI were consistent with the one for pain. Correlations with VAS, CSQ and SF-12 were similar for NDI and NPQ (absolute values between 0.36 and 0.50 on day 1, between 0.38 and 0.70 on day 15), and slightly lower for COM (between 0.36 and 0.48 on day 1, and between 0.33 and 0.61 on day 15). Correlation between NDI and NPQ: r = 0.84 on day 1, r = 0.91 on day 15. Correlation between COM and NPQ: r = 0.63 on day 1, r = 0.71 on day 15.
Conclusion: Although most psychometric characteristics of NDI, NPQ and COM are similar, those from the latter one are worse and its use may lead to patients' evolution seeming more positive than it actually is. NDI seems to be the best instrument for measuring NP-related disability, since its results are the most consistent with patient's assessment of their own clinical status and evolution. It takes two more minutes to answer the NDI than to answer the COM, but it can be reliably filled out by the patient without assistance
Feasibility of a screening algorithm for chronic thromboembolic pulmonary hypertension: The OSIRIS study
© 2023 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/bync-nd/4.0/)[Introduction] Chronic thromboembolic pulmonary hypertension (CTEPH) is a long-term sequel to pulmonary embolism (PE) whose incidence varies according to different published studies. We have carried out this study to determine its incidence within 2 years after index pulmonary embolism and to study limitations to an early diagnosis.[Material and methods] OSIRIS is a multicentre, longitudinal cohort study. Patients were followed for 3, 6, 12, and 24 months after pulmonary embolism using a structured three-step algorithm. A physician-centered questionnaire at least one positive response in a screening proceeded to the second step, transthoracic echocardiography. The third step consisted of ventilation/perfusion lung scintigraphy and right heart catheterisation. A transthoracic echocardiography was performed in patients without positive response in the screening questionnaire after 2 years. CTEPH diagnosis required haemodynamic confirmation by right heart catheterisation and mismatched perfusion defects on lung scintigraphy.[Results] A total of 1191 patients were enrolled in 18 Spanish hospitals. Cumulative CTEPH incidence after 2-years PE was: 2.49 % (95 % CI: 1.68–3.56) and the incidence rate of CTEPH was 1.1 cases per 1000 person-months (95 % CI: 0.725; 1.60). The CTEPH algorithm presented a lack of adherence of 29 %; patient and physician preferences posed barriers to the triage algorithm The screening questionnaire, in patients who completed the follow-up, shows a specificity of 91.3 % (89.0–93.2 %) and negative predictive value of 99.4 % (98.4–99.8 %).[Conclusions] OSIRIS provides practiced clinical based data on the chronic thromboembolic pulmonary hypertension incidence and identified barriers to the implementation of a 3-step triage algorithm for its detection.This study was supported by Instituto de Salud Carlos III (PI15/01085 and PI18/01640), Sociedad Española de Neumologia y Cirugia Torácica (SEPAR) and Bayer Hispania SL.Peer reviewe
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