Parsimonious spatial representation of tropical soils within dynamic rainfall-runoff models

Introduction Models are used increasingly to simulate hydrological processes within tropical regions. There is now a wealth of publications addressing evaporation modelling (particularly wet-canopy evaporation) of local areas of tropical forest in, for example, Niger (Gash et al., 1997), Guyana (Jetten, 1996), Puerto Rico (Schellekens et al., 1999), Columbia (Marin et al., 2000) and Indonesia (Asdak et al., 1999; van Dijk and Bruijnzeel, 2001). Elsewhere in this volume, Roberts et al. provide an overview of evaporation processes and modelling. Other modelling studies have addressed the impact of such tropical evaporation on regional climates and global circulation (e.g. Polcher and Laval, 1994; Zeng, 1999; Zeng and Neelin, 1999; Zheng et al., 2001). New studies using time-series models are highlighting the effects of cycles in the rainfall, such as the El Nino Southern Oscillation (ENSO) on tropical evaporation, riverflow and water quality (e.g. Zeng, 1999; Chappell et al., 2001; Krishnaswamy et al., 2001; Whitaker et al., 2001; Chappell, Tych et al., this volume). Similarly, models that simulate the generation of riverflow from the rainfall received by a tropical catchment are also beginning to be applied more frequently. These models include: Metric-conceptual models of waterflow, based upon transfer functions. For example, application of the DBM modelling approach to a nested catchment system in Malaysian Borneo (Chappell et al., 1999a) and the application of IHACRES to a large Thai basin (Scoccimarro et al., 1999). Conceptual models of waterflow based upon stores and pre-determined empirical relationships. For example, application of the Nash model to Kenyan catchments (Onyando and Sharma, 1995), the Modhydrolog model to a tropical catchment (Chiew et al., 1996), the Reservoir-Water-Balance-Simulation model to Namibian catchments (Hughes and Metzler, 1998), and the HBV-96 model (discussed in Barnes and Bonell, this volume) to catchments in Zimbabwe, Tanzania and Bolivia (Liden and Harlin, 2000).[&]. © UNESCO 2005 and Cambridge University Press, 2009

Canadian Association of Gastroenterology Clinical Practice Guideline for the Medical Management of Pediatric Luminal Crohn's Disease

Background & Aims: We aim to provide guidance for medical treatment of luminal Crohn's disease in children. Methods: We performed a systematic search of publication databases to identify studies of medical management of pediatric Crohn's disease. Quality of evidence and strength of recommendations were rated according to the GRADE (Grading of Recommendation Assessment, Development, and Evaluation) approach. We developed statements through an iterative online platform and then finalized and voted on them. Results: The consensus includes 25 statements focused on medical treatment options. Consensus was not reached, and no recommendations were made, for 14 additional statements, largely due to lack of evidence. The group suggested corticosteroid therapies (including budesonide for mild to moderate disease). The group suggested exclusive enteral nutrition for induction therapy and biologic tumor necrosis factor antagonists for induction and maintenance therapy at diagnosis or at early stages of severe disease, and for patients failed by steroid and immunosuppressant induction therapies. The group recommended against the use of oral 5-aminosalicylate for induction or maintenance therapy in patients with moderate disease, and recommended against thiopurines for induction therapy, corticosteroids for maintenance therapy, and cannabis in any role. The group was unable to clearly define the role of concomitant immunosuppressants during initiation therapy with a biologic agent, although thiopurine combinations are not recommended for male patients. No consensus was reached on the role of aminosalicylates in treatment of patients with mild disease, antibiotics or vedolizumab for induction or maintenance therapy, or methotrexate for induction therapy. Patients in clinical remission who are receiving immunomodulators should be assessed for mucosal healing within 1 year of treatment initiation. Conclusions: Evidence-based medical treatment of Crohn's disease in children is recommended, with thorough ongoing assessments to define treatment success

Development and application of feature engineered geological layers for ranking magmatic, volcanogenic, and orogenic system components in Archean greenstone belts

Geologically representative feature engineering is a crucial component in geoscientific applications of machine learning. Many commonly applied feature engineering techniques used to produce input variables for machine learning apply geological knowledge to generic data science techniques, which can lead to ambiguity, geological oversimplification, and/or compounding subjective bias. Workflows that utilize minimally processed input variables attempt to overcome these issues, but often lead to convoluted and uninterpretable results. To address these challenges, new and enhanced feature engineering methods were developed by combining geological knowledge, understanding of data limitations, and a variety of data science techniques. These include non-Euclidean fluid pre-deformation path distance, rheological and chemical contrast, geologically constrained interpolation of characteristic host rock geochemistry, interpolation of mobile element gain/loss, assemblages, magnetic intensity, structural complexity, host rock physical properties. These methods were applied to compiled open-source and new field observations from Archean greenstone terranes in the Abitibi and western Wabigoon sub-provinces of the Superior Province near Timmins and Dryden, Ontario, respectively. Resulting feature maps represent conceptually significant components in magmatic, volcanogenic, and orogenic mineral systems. A comparison of ranked feature importance from random forests to conceptual mineral system models show that the feature maps adequately represent system components, with a few exceptions attributed to biased training data or limited constraint data. The study also highlights the shared importance of several highly ranked features for the three mineral systems, indicating that spatially related mineral systems exploit the same features when available. Comparing feature importance when classifying orogenic Au mineralization in Timmins and Dryden provides insights into the possible cause of contrasting endowment being related to fluid source. The study demonstrates that integrative studies leveraging multi-disciplinary data and methodology have the potential to advance geological understanding, maximize data utility, and generate robust exploration targets