Hydrological restoration of Indonesian peatlands to mitigate carbon dioxide emissions

Delta Session DS 9: The lowland deltas of Indonesia. Hydrological restoration of Indonesian peatlands to mitigate carbon dioxide emissions, Henk Wösten (2010). Presented at the international conference Deltas in Times of Climate Change, 29 September - 1 October, Rotterdam, the Netherlands

Cytoplasmic Continuity Revisited: Closure of Septa of the Filamentous Fungus Schizophyllum commune in Response to Environmental Conditions

Background: Mycelia of higher fungi consist of interconnected hyphae that are compartmentalized by septa. These septa contain large pores that allow streaming of cytoplasm and even organelles. The cytoplasm of such mycelia is therefore considered to be continuous. Methodology/Principal Findings: Here, we show by laser dissection that septa of Schizophyllum commune can be closed depending on the environmental conditions. The most apical septum of growing hyphae was open when this basidiomycete was grown in minimal medium with glucose as a carbon source. In contrast, the second and the third septum were closed in more than 50 % and 90 % of the cases, respectively. Interestingly, only 24 and 37 % of these septa were closed when hyphae were growing in the absence of glucose. Whether a septum was open or closed also depended on physical conditions of the environment or the presence of toxic agents. The first septum closed when hyphae were exposed to high temperature, to hypertonic conditions, or to the antibiotic nourseothricin. In the case of high temperature, septa opened again when the mycelium was placed back to the normal growth temperature. Conclusions/Significance: Taken together, it is concluded that the septal pores of S. commune are dynamic structures that open or close depending on the environmental conditions. Our findings imply that the cytoplasm in the mycelium of

Absence of repellents in Ustilago maydis induces genes encoding small secreted proteins

The rep1 gene of the maize pathogen Ustilago maydis encodes a pre-pro-protein that is processed in the secretory pathway into 11 peptides. These so-called repellents form amphipathic amyloid fibrils at the surface of aerial hyphae. A SG200 strain in which the rep1 gene is inactivated (∆rep1 strain) is affected in aerial hyphae formation. We here assessed changes in global gene expression as a consequence of the inactivation of the rep1 gene. Microarray analysis revealed that only 31 genes in the ∆rep1 SG200 strain had a fold change in expression of ≥2. Twenty-two of these genes were up-regulated and half of them encode small secreted proteins (SSPs) with unknown functions. Seven of the SSP genes and two other genes that are over-expressed in the ∆rep1 SG200 strain encode proteins that can be classified as secreted cysteine-rich proteins (SCRPs). Interestingly, most of the SCRPs are predicted to form amyloids. The SCRP gene um00792 showed the highest up-regulation in the ∆rep1 strain. Using GFP as a reporter, it was shown that this gene is over-expressed in the layer of hyphae at the medium-air interface. Taken together, it is concluded that inactivation of rep1 hardly affects the expression profile of U. maydis, despite the fact that the mutant strain has a strong reduced ability to form aerial hyphae

Canal blocking strategies for hydrological restoration of degraded tropical peatlands in Central Kalimantan, Indonesia

In the 1990s the Government of Indonesia derided to develop one million hectares of peatlands for agriculture in Central Kalimantan on the Island of Borneo. The construction of thousands of kilometres of canals resulted in over-drainage and targets for agricultural production failed. Abandoned, the area has been subject to severe forest and peat fires. Restoration of degraded peatlands normally starts with restoring the water table to rewet the surface in order to control fire and to initiate reforestation. Canal blocking strategies are a potential means for accomplishing this. In a test plot in the Northern part of Block C of the former Mega Rice Project (MRP), a series of dams were constructed and (ground)water tables and subsidence rates were monitored to assess the effects of dam construction on peatland hydrology. The resulting higher water tables did not completely compensate for the negative effects of increased subsidence near the canals. The canals, which are "eating" themselves into the peatland, create depressions in the peatland surface leading to interception of overland- and interflow and increased risk of overtopping of dams during extreme rainfall events. The lessons learned are being used to improve blocking strategies and dam design. The changes in peatland topography caused by drainage, however, need to be better understood in order to further refine strategies for hydrological restoration of degraded peatlands in Indonesia. (C) 2013 Elsevier B.V. All rights reserved

Особливості розв’язку задач параметричної ідентифікації динамічних систем в умовах інтервальної невизначеності

Розглянуто задачу параметричної ідентифікації лінійних динамічних систем методами аналізу інтервальних даних. Показано, що у випадку врахування початкових інтервальних наближень дискретних значень прогнозованої характеристики дана задача є задачею розв’язування інтервальної системи нелінійних алгебричних рівнянь. Досліджено особливості формування та властивості розв’язку таких систем.Рассмотрена задача параметрической идентификации линейных динамических систем методами анализа интервальных данных. Показано, что в случае учета начальных интервальных приближений дискретных значений прогнозированной характеристики, данная задача есть задачей решения интервальной системы нелинейных алгебраических уравнений; исследованы особенности формирования и свойства решения таких систем.The problem of parameter identification of linear dynamic systems by methods of analysis of interval data is considered. It is shown that in the case of taking into account the initial interval approximations of discrete values of the predicted characteristics, this problem is the problem of solving interval system of nonlinear algebraic equations

Prognostic factors for multi-organ dysfunction in pediatric oncology patients admitted to the pediatric intensive care unit

Background: Pediatric oncology patients who require admission to the pediatric intensive care unit (PICU) have worse outcomes compared to their non-cancer peers. Although multi-organ dysfunction (MOD) plays a pivotal role in PICU mortality and morbidity, risk factors for MOD have not yet been identified. We aimed to identify risk factors at PICU admission for new or progressive MOD (NPMOD) during the first week of PICU stay.Methods: This retrospective cohort study included all pediatric oncology patients aged 0 to 18 years admitted to the PICU between June 2018 and June 2021. We used the recently published PODIUM criteria for defining multi-organ dysfunction and estimated the association between covariates at PICU baseline and the outcome NPMOD using a multivariable logistic regression model, with PICU admission as unit of study. To study the predictive performance, the model was internally validated by using bootstrap.Results: A total of 761 PICU admissions of 571 patients were included. NPMOD was present in 154 PICU admissions (20%). Patients with NPMOD had a high mortality compared to patients without NPMOD, 14% and 1.0% respectively. Hemato-oncological diagnosis, number of failing organs and unplanned admission were independent risk factors for NPMOD. The prognostic model had an overall good discrimination and calibration.Conclusion: The risk factors at PICU admission for NPMOD may help to identify patients who may benefit from closer monitoring and early interventions. When applying the PODIUM criteria, we found some opportunities for fine-tuning these criteria for pediatric oncology patients, that need to be validated in future studies.</p

Prognostic factors for multi-organ dysfunction in pediatric oncology patients admitted to the pediatric intensive care unit

Background: Pediatric oncology patients who require admission to the pediatric intensive care unit (PICU) have worse outcomes compared to their non-cancer peers. Although multi-organ dysfunction (MOD) plays a pivotal role in PICU mortality and morbidity, risk factors for MOD have not yet been identified. We aimed to identify risk factors at PICU admission for new or progressive MOD (NPMOD) during the first week of PICU stay.Methods: This retrospective cohort study included all pediatric oncology patients aged 0 to 18 years admitted to the PICU between June 2018 and June 2021. We used the recently published PODIUM criteria for defining multi-organ dysfunction and estimated the association between covariates at PICU baseline and the outcome NPMOD using a multivariable logistic regression model, with PICU admission as unit of study. To study the predictive performance, the model was internally validated by using bootstrap.Results: A total of 761 PICU admissions of 571 patients were included. NPMOD was present in 154 PICU admissions (20%). Patients with NPMOD had a high mortality compared to patients without NPMOD, 14% and 1.0% respectively. Hemato-oncological diagnosis, number of failing organs and unplanned admission were independent risk factors for NPMOD. The prognostic model had an overall good discrimination and calibration.Conclusion: The risk factors at PICU admission for NPMOD may help to identify patients who may benefit from closer monitoring and early interventions. When applying the PODIUM criteria, we found some opportunities for fine-tuning these criteria for pediatric oncology patients, that need to be validated in future studies.</p