196,054 research outputs found
Preface. Climate change impact on plant ecology
No full textThe variety and the number of ecological models is impressive, and several fields of exact sciences have been called upon to provide the technical and informatics tools that have made it possible to define their current and future developments. But even taking into consideration only a part of the ecosystem, such as the one assigned to primary production (first trophic level, photo-autotrophic compartment), our ability to simulate the processes that underlie carbon fixation in plants is limited by our current knowledge, determining a quantity of information or variability not explained by the model used, which underlies a sort of ‘Uncertainty Principle’ valid for the ecological sciences. The design of Nature and its state of apparent disorder at the various levels of hierarchical, spatial, and temporal scales is still far from being fully discovered. Although the word ‘uncertainty’ resonates widely in this paper, it can represent a very key source of information and the force that pushes us to try other ways to increase our level of knowledge and make our simulation and forecasting ability more and more accurate in a complex world
Changes in Mean Seasonal Carbon Cycle Due to Climate Change
No full text<p>This repository contains the output data of the 3D-CMCC-FEM model (https://github.com/Forest-Modelling-Lab/3D-CMCC-FEM/tree/v.5.6) related to the manuscript entitled "Changes in Mean Seasonal Carbon Cycle Due to Climate Change" by Morichetti M. and Collalti A. 2024</p>
Plant respiration: Controlled by photosynthesis or biomass?
No full textTwo simplifying hypotheses have been proposed for whole‐plant respiration. One links respiration to photosynthesis; the other to biomass. Using a first‐principles carbon balance model with a prescribed live woody biomass turnover, applied at a forest research site where multidecadal measurements are available for comparison, we show that if turnover is fast the accumulation of respiring biomass is low and respiration depends primarily on photosynthesis; while if turnover is slow the accumulation of respiring biomass is high and respiration depends primarily on biomass. But the first scenario is inconsistent with evidence for substantial carry‐over of fixed carbon between years, while the second implies far too great an increase in respiration during stand development—leading to depleted carbohydrate reserves and an unrealistically high mortality risk. These two mutually incompatible hypotheses are thus both incorrect. Respiration is not linearly related either to photosynthesis or to biomass, but it is more strongly controlled by recent photosynthates (and reserve availability) than by total biomass
Spontaneous transdiaphragmatic intercostal hernia: Clinical considerations and management
No full textMost diaphragmatic ruptures are due to the traumatic or penetrating injury, while the spontaneous diaphragmatic rupture is consi-dered uncommon. The spontaneous transdiaphragmatic hernia is a consequence of violent coughing, vomiting that increase the thoracoabdominal pressure causing the diaphragmatic rupture. Even rarer is the concomitant prolapse of abdominal viscera into the thoracic subcutis through the chest wall, a condition known as spontaneous transdiaphragmatic intercostal hernia. Herein, we present a rare case of spontaneous transdiaphragmatic intercostal hernia presenting as a thoracoabdominal emergency
A process-based model to simulate growth in forests with complex structure: Evaluation and use of 3D-CMCC Forest Ecosystem Model in a deciduous forest in Central Italy
No full textForest ecosystems are characterized by high spatial heterogeneity, often related to complex composition and vertical structure which is a challenge in many process-based models. The need to expand process-based models (PBMs) to take in account such structural complexity led to development and testing of a new approach into Forest Ecosystem Models (FEMs), named 3D-CMCC-FEM, able to investigate carbon and water fluxes, including biomass pools and their partitioning, for complex multi-layer forests. 3D-CMCC FEM integrates several characteristics of the functional-structural tree models and the robustness of the light use efficiency (LUE) approach to investigate forest growth patterns and yield processes. The modelling approach was tested by simulating the effects of competition for light and water, growth and yield of a two-layered deciduous forest dominated by Turkey Oak in central Italy for a period of eight years. The model outputs were validated against a series of independently measured data for the major biomass pools, the inter-annual stem increments and above-ground net primary productivity of the overstorey and understorey, respectively. The comparison of Leaf Area Index, Gross Primary Production, and evapotranspiration produced by the model against MODIS data showed agreement in results. In addition, the multi-layered model approach was evaluated against a series of simplified versions to determine whether the enhanced complexity of the model positively contributed to its predictive ability. The proposed model reduced the error in the estimates of forest productivity (e.g. NPP) and dynamics (e.g. growth, mortality) and indicates the importance of considering, as far as possible, the structural complexity in PBMs. © 2013 Elsevier B.V
Dr. Duane M. Jackson, Morehouse College, July 2011
No full textThis video is a conversation with Dr. Duane M. Jackson. Dr. Jackson talks about his paper, "Recall and the Serial Position Effect: The Role of Primacy and Recency on Accounting Students' Performance." Jackie Daniel, AUC Woodruff Library, is the interviewer
"Reflections on the subject of Emigration from Europe with a view to Settlement in the United States" By M. Carey.
No full text"Reflections on the subject of Emigration from Europe with a view to Settlement in the United States: containing bried sketches of the moral and political character of those states.
By M. Carey, member of the American philosophical, and of the American Antiquarian Society, and author of The Olive Branch, Cindiciae Hibernicae, essays on banking, on political economy, and on internal improvement.
To which are now added the English editor's comments on the subject; together with Important Advice to Emigrants, and Cautions Against Impositions Practiced in the Outports
Vaccination in pads
No full textPrimary antibody deficiencies (PADs) are the most common primary immunodeficiencies (PIDs). They can be divided into the following groups, depending on their immunological features: agammaglobulinemia; common variable immunodeficiency (CVID) isotype; hyper IgM isotype; light chain or functional deficiencies with normal B cell count; specific antibody deficiency with normal Ig concentrations and normal numbers of B cells and transient hypogammaglobulinemia of infancy. The role of vaccination in PADs is recognized as therapeutic, diagnostic and prognostic and may be used in patients with residual B-cell function to provide humoral immunity to specific infective agents. According to their content and mechanisms, vaccines are grouped as live attenuated, inactivated (conjugated, polysaccharide), mRNA or replication-deficient vector vaccines. Vaccination may be unsafe or less effective when using certain vaccines and in specific types of immunodeficiency. Inactivated vaccines can be administered in PAD patients even if they could not generate a protective response; live attenuated vaccines are not recommended in major antibody deficiencies. From December 2020, European Medicines Agency (EMA) approved vaccines against COVID-19 infection: according to ESID advises, those vaccinations are recommended in patients with PADs. No specific data are available on safety and efficacy in PAD patients
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