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Background and Aims: There is a paucity of empirical research and a lack of predictive models concerning the interplay between spatial scale and disturbance as they affect the structure and assembly of plant communities. We proposed and tested a trait dispersion-based conceptual model hypothesizing that disturbance reinforces assembly processes differentially across spatial scales. Disturbance would reinforce functional divergence at the small scale (neighbourhood), would not affect functional dispersion at the intermediate scale (patch) and would reinforce functional convergence at the large scale (site). We also evaluated functional and species richness of native and exotic plants to infer underlying processes. Native and exotic species richness were expected to increase and decrease with disturbance, respectively, at the neighbourhood scale, and to show similar associations with disturbance at the patch (concave) and site (negative) scales., Methods: In an arid shrubland, we estimated species richness and functional dispersion and richness within 1 m2 quadrats (neighbourhood) nested within 100 m2 plots (patch) along a small-scale natural disturbance gradient caused by an endemic fossorial rodent. Data for the site scale (2500 m2 plots) were taken from a previous study. We also tested the conceptual model through a quantitative literature review and a meta-analysis., Key Results: As spatial scale increased, disturbance sequentially promoted functional divergence, random trait dispersion and functional convergence. Functional richness was unaffected by disturbance across spatial scales. Disturbance favoured natives over exotics at the neighbourhood scale, while both decreased under high disturbance at the patch and site scales., Conclusions: The results supported the hypothesis that disturbance reinforces assembly processes differentially across scales and hampers plant invasion. The quantitative literature review and the meta-analysis supported most of the model predictions., (© The Author(s) 2020. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Introduction: Home parenteral nutrition (HPN) has been shown to offer important benefits for pa tients and the health system. In Chile, the number of patients who are receiving this type of treatment or who could be candidates for it is unknown. Objetive: To determine the prevalence and clinical characteristics of patients with intestinal insufficiency (II) currently receiving HPN or who are can didates for it., Patients and Method: Cross-sectional descriptive study which included patients aged between 0 to 18 years with diagnosis of II who were receiving parenteral nutrition (PN) for over three months, either at home or in the hospital, with a stable clinical situation and a long-term venous catheter (CVC). Through a digitalized survey, the following variables were collected and studied: gender, birth history, indication to initiate parenteral nutritional support, age of initiation of PN, type of CVC, frequency of PN, nutritional status and feeding in the last control and complications as sociated with the use of PN. Data analysis was performed using the SPSS Statistics Software, Version 21, Macintosh. The descriptive analysis considered frequency analysis and central trend measures. The Chi-square and Fisher tests were used for comparison of proportions., Results: Data from 46 patients were recorded. The average age was 55.5 months. The main indication for initiating the PN was the decrease of the intestinal surface (78.3%). 63% of the patients were hospitalized. No signi ficant differences were found between the place of treatment and the nutritional status and catheter infections variables in the last year., Conclusions: The prevalence of patients with long-term PN and their clinical characteristics were identified. No differences were found to support the administration of this treatment in the hospital over the home. Public policies must be developed to guarantee the option of receiving this treatment at home.

Melkersson proposed leptin dysregulation as a factor in the olanzapine-induced metabolic dysfunction. Their suggestion was based on the absence of the expected positive correlation between serum leptin levels and the BMI, and the loss of the sex-dependent difference in leptin levels, which are higher in women. Although subsequent studies did not confirm that proposal, few of them assessed basal leptin levels and corrected for body fat percentage. Along with these variables, we added a precise definition of participants out of the expected positive correlation in a large sample of schizophrenia patients. Sixty patients (26 women and 34 men) with severe schizophrenia undergoing chronic hospitalization and conventional antipsychotic treatment were switched to olanzapine (10-20 mg/day). We assessed at baseline, and at weeks 8 and 16 of treatment, the percentage of participants with abnormal correlation (out of the 95% confidence interval in the regression line) between leptin levels and the BMI, and the correlation between leptin and insulin, glucose, the insulin resistance index, c-reactive protein (CRP) and treatment response. Leptin levels were higher in women than in men (P<0.01). The positive correlation between leptin levels, BMI and percentage of fat were preserved. After olanzapine, 3.8% of women and 2.9-5.8% of men were out the 95% confidence interval, and the proportion was similar at baseline. Glucose, insulin, the insulin resistance index and the CRP levels significantly increased after olanzapine. The impact of olanzapine on leptin regulation appears discrete and limited to a small number of participants. Additional studies must clarify the features that render them to metabolic dysregulation.