364 research outputs found

    The ability of a host plant to associate with different symbiotic partners affects ectomycorrhizal functioning

    Get PDF
    Some plants that associate with ectomycorrhizal (ECM) fungi are also able to simultaneously establish symbiosis with other types of partners. The presence of alternative partners that may provide similar benefits may affect ECM functioning. Here we compared potential leucine-aminopeptidase (LA) and acid phosphatase (AP) enzyme activity (involved in N and P cycling, respectively) in ECM fungi of three hosts planted under the same conditions but differing in the type of partners: Pinus (ECM fungi only), Eucalyptus (ECM and arbuscular mycorrhizal -AM- fungi) and Acacia (ECM, AM fungi and rhizobial bacteria). We found that the ECM community on Acacia and Eucalyptus had higher potential AP activity than the Pinus community. The ECM community in Acacia also showed increased potential LA activity compared to Pinus. Morphotypes present in more than one host showed higher potential AP and LA activity when colonizing Acacia than when colonizing another host. Our results suggest that competition with AM fungi and rhizobial bacteria could promote increased ECM activity in Eucalyptus and Acacia. Alternatively, other host-related differences such as ECM community composition could also play a role. We found evidence for ECM physiological plasticity when colonizing different hosts, which might be key for adaptation to future climate scenarios.info:eu-repo/semantics/acceptedVersio

    pysteps - a community-driven open-source library for precipitation nowcasting

    Get PDF
    PĂłster presentado en: 3rd European Nowcasting Conference, celebrada en la sede central de AEMET en Madrid del 24 al 26 de abril de 2019

    Tearing Out the Income Tax by the (Grass)Roots

    Get PDF
    Landscapes are increasingly fragmented, and conservation programs have started to look at network approaches for maintaining populations at a larger scale. We present an agent-based model of predator–prey dynamics where the agents (i.e. the individuals of either the predator or prey population) are able to move between different patches in a landscaped network. We then analyze population level and coexistence probability given node-centrality measures that characterize specific patches. We show that both predator and prey species benefit from living in globally well-connected patches (i.e. with high closeness centrality). However, the maximum number of prey species is reached, on average, at lower closeness centrality levels than for predator species. Hence, prey species benefit from constraints imposed on species movement in fragmented landscapes since they can reproduce with a lesser risk of predation, and their need for using anti-predatory strategies decreases.authorCount :

    Two novel variants of the ABCG5 gene cause xanthelasmas and macrothrombocytopenia: a brief review of hematologic abnormalities of sitosterolemia

    Get PDF
    [EN] Background: Sitosterolemia (STSL) is a recessive inherited disorder caused by pathogenic variants in the ABCG5 and ABCG8 genes. Increased levels of plasma plant sterols (PSs) usually result in xanthomas and premature coronary atherosclerosis, although hematologic abnormalities may occasionally be present. This clinical picture is unfamiliar to many physicians, and patients may be at high risk of misdiagnosis. Objectives: To report two novel ABCG5 variants causing STSL in a Spanish patient, and review the clinical and mutational landscape of STSL. Patient/Methods: A 46-year-old female was referred to us with lifelong macrothrombocytopenia. She showed familial hypercholesterolemia-related xanthomas. Molecular analysis was performed with high-throughput sequencing. Plasma PS levels were evaluated with gas–liquid chromatography. The STSL landscape was reviewed with respect to specific online databases and all reports published since 1974. Results: A blood smear revealed giant platelets and stomatocytes. Novel compound heterozygous variants were detected in exons 7 (c.914C>G) and 13 (c.1890delT) of ABCG5. The patient showed an increased plasma level of sitosterol. These findings support the diagnosis of STSL. In our review, we identified only 25 unrelated STLS patients who presented with hematologic abnormalities including macrothrombocytopenia

    An evaluation of an adaptive learning system based on multimodal affect recognition for learners with intellectual disabilities

    Get PDF
    Artificial intelligence tools for education (AIEd) have been used to automate the provision of learning support to mainstream learners. One of the most innovative approaches in this field is the use of data and machine learning for the detection of a student's affective state, to move them out of negative states that inhibit learning, into positive states such as engagement. In spite of their obvious potential to provide the personalisation that would give extra support for learners with intellectual disabilities, little work on AIEd systems that utilise affect recognition currently addresses this group. Our system used multimodal sensor data and machine learning to first identify three affective states linked to learning (engagement, frustration, boredom) and second determine the presentation of learning content so that the learner is maintained in an optimal affective state and rate of learning is maximised. To evaluate this adaptive learning system, 67 participants aged between 6 and 18 years acting as their own control took part in a series of sessions using the system. Sessions alternated between using the system with both affect detection and learning achievement to drive the selection of learning content (intervention) and using learning achievement alone (control) to drive the selection of learning content. Lack of boredom was the state with the strongest link to achievement, with both frustration and engagement positively related to achievement. There was significantly more engagement and less boredom in intervention than control sessions, but no significant difference in achievement. These results suggest that engagement does increase when activities are tailored to the personal needs and emotional state of the learner and that the system was promoting affective states that in turn promote learning. However, longer exposure is necessary to determine the effect on learning

    Are there independent predisposing factors for postoperative infections following open heart surgery?

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Nosocomial infections after cardiac surgery represent serious complications associated with substantial morbidity, mortality and economic burden. This study was undertaken to evaluate the frequency, characteristics, and risk factors of microbiologically documented nosocomial infections after cardiac surgery in a Cardio-Vascular Intensive Care Unit (CVICU).</p> <p>Methods</p> <p>All patients who underwent open heart surgery between May 2006 and March 2008 were enrolled in this prospective study. Pre-, intra- and postoperative variables were collected and examined as possible risk factors for development of nosocomial infections. The diagnosis of infection was always microbiologically confirmed.</p> <p>Results</p> <p>Infection occurred in 24 of 172 patients (13.95%). Out of 172 patients, 8 patients (4.65%) had superficial wound infection at the sternotomy site, 5 patients (2.9%) had central venous catheter infection, 4 patients (2.32%) had pneumonia, 9 patients (5.23%) had bacteremia, one patient (0.58%) had mediastinitis, one (0.58%) had harvest surgical site infection, one (0.58%) had urinary tract infection, and another one patient (0.58%) had other major infection. The mortality rate was 25% among the patients with infection and 3.48% among all patients who underwent cardiac surgery compared with 5.4% of patients who did not develop early postoperative infection after cardiac surgery. Culture results demonstrated equal frequencies of gram-positive cocci and gram-negative bacteria. A backward stepwise multivariable logistic regression model analysis identified diabetes mellitus (OR 5.92, CI 1.56 to 22.42, p = 0.009), duration of mechanical ventilation (OR 1.30, CI 1.005 to 1.69, p = 0.046), development of severe complications in the CICU (OR 18.66, CI 3.36 to 103.61, p = 0.001) and re-admission to the CVICU (OR 8.59, CI 2.02 to 36.45, p = 0.004) as independent risk factors associated with development of nosocomial infection after cardiac surgery.</p> <p>Conclusions</p> <p>We concluded that diabetes mellitus, the duration of mechanical ventilation, the presence of complications irrelevant to the infection during CVICU stay and CVICU re-admission are independent risk factors for the development of postoperative infection in cardiac surgery patients.</p

    Long-term medical utilization following ventilator-associated pneumonia in acute stroke and traumatic brain injury patients: a case-control study

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>The economic burden of ventilator-associated pneumonia (VAP) during the index hospitalization has been confirmed in previous studies. However, the long-term economic impact is still unclear. The aim of this study is to examine the effect of VAP on medical utilization in the long term.</p> <p>Methods</p> <p>This is a retrospective case-control study. Study subjects were patients experiencing their first traumatic brain injury, acute hemorrhagic stroke, or acute ischemic stroke during 2004. All subjects underwent endotracheal intubation in the emergency room (ER) on the day of admission or the day before admission, were transferred to the intensive care unit (ICU) and were mechanically ventilated for 48 hours or more. A total of 943 patients who developed VAP were included as the case group, and each was matched with two control patients without VAP by age ( ± 2 years), gender, diagnosis, date of admission ( ± 1 month) and hospital size, resulting in a total of 2,802 patients in the study. Using robust regression and Poisson regression models we examined the effect of VAP on medical utilization including hospitalization expenses, outpatient expenses, total medical expenses, number of ER visits, number of readmissions, number of hospitalization days and number of ICU days, during the index hospitalization and during the following 2-year period.</p> <p>Results</p> <p>Patients in the VAP group had higher hospitalization expenses, longer length of stay in hospital and in ICU, and a greater number of readmissions than the control group patients.</p> <p>Conclusions</p> <p>VAP has a significant impact on medical expenses and utilization, both during the index hospitalization during which VAP developed and in the longer term.</p
    • 

    corecore