Co-limitation towards lower latitudes shapes global forest diversity gradients

The latitudinal diversity gradient (LDG) is one of the most recognized global patterns of species richness exhibited across a wide range of taxa. Numerous hypotheses have been proposed in the past two centuries to explain LDG, but rigorous tests of the drivers of LDGs have been limited by a lack of high-quality global species richness data. Here we produce a high-resolution (0.025° × 0.025°) map of local tree species richness using a global forest inventory database with individual tree information and local biophysical characteristics from ~1.3 million sample plots. We then quantify drivers of local tree species richness patterns across latitudes. Generally, annual mean temperature was a dominant predictor of tree species richness, which is most consistent with the metabolic theory of biodiversity (MTB). However, MTB underestimated LDG in the tropics, where high species richness was also moderated by topographic, soil and anthropogenic factors operating at local scales. Given that local landscape variables operate synergistically with bioclimatic factors in shaping the global LDG pattern, we suggest that MTB be extended to account for co-limitation by subordinate drivers

DEEDS: Fully Integrating Data and Computational Workflows

<div>The OAC has recognized the emerging and evolving need for platforms that fully integrate data and computing. DEEDS is responding to this need by creating a cross-domain platform that provides a full range of services for data preservation, sharing, exploration, and discovery, and also offers comprehensive support for computational tools and scientific workflows. Interactive data interfaces are directly connected to the launch, execution, tracking, and output handling of computing tools, and research workflows are captured end-to-end. Our user-friendly DEEDS dashboard helps research groups create project datasets, describe research activities, collect files, assemble structured data, execute tools, auto-return and annotate results, capture computational workflows, and further analyze and compare results. DEEDS viewers operate on data by type and use to facilitate easy exploration of datasets and their heterogeneous content. </div><div> </div><div>Most research groups carry out their investigations in an ad hoc way, without infrastructure for preserving, linking, sharing, and publishing their data, tools, and research workflows. Our greatest challenge was designing and building DEEDS in a way that would meet the data and computing needs of researchers with very different scientific workflows – delivering a platform with comprehensive services that is truly effective across disciplines.</div><div><br></div><div>We partnered with researchers from four science domains: </div><div>* computational chemistry: molecular structure optimization and determination of properties </div><div>* electrical engineering: performance modeling of solar photovoltaic systems</div><div>* nutrition science: clinical trial to measure effects of diet on net calcium retention </div><div>* environmental science: amphibian toxicity study for ecological risk assessment </div><div><br></div><div>Use case requirements encompassed complex structured data models, file repositories, computing software, execution resources, and workflow tracking for results traceability, team learning, and holistic data re-use – with a single dataset dashboard connecting interactive data interfaces to computational tools and workflows. These needs are satisfied by DEEDS innovations, such as our “spreadsheets of spreadsheets” approach to structured data representation; a full-featured execution submit layer; the automatic upload, annotation and classification of computational output; the capture of research workflows end-to-end; and an extensible data definition language that dynamically creates and presents interactive views for any combination of heterogeneous dataset content for search and exploration.</div

PDELab: An Object-Oriented Framework for Building Problem Solving Environments for PDE Based Applications

In this paper we present an object-oriented methodology and tools for creating high level, high performance problem solving systems (workbenches) for scientific applications modeled by partial differential equations. This methodology is validated by the creation of a scientific computing workbench for bioseparation analysis. One of the design objectives of PDELab is to provide workbench developers and users with much the same kind of independence in software as they have come to expect in hardware. The adopted architecture of this software platform for creating problem solving environments for PDE applications is devoted to &quot;clean layering.&quot; At the bottom are the various &quot;smart&quot; libraries that support the numerical simulation of various &quot;physical&quot; objects together with the corresponding knowledge bases needed to support the computational intelligence aspects of the various workbenches; at the top is a set of interactive tools that allow the user to carry out his objectives ..

Video query processing in the vdbms testbed for video database research

The increased use of video data sets for multimedia-based applications has created a demand for strong video database support, including efficient methods for handling the content-based query and retrieval of video data. Video query processing presents significant research challenges, mainly associated with the size, complexity and unstructured nature of video data. A video query processor must support video operations for search by content and streaming, new query types, and the incorporation of video methods and operators in generating, optimizing and executing query plans. In this paper, we address these query processing issues in two contexts, first as applied to the video data type and then as applied to the stream data type. We first present the query processing functionality of the VDBMS video database management system as a framework designed to support the full range of functionality fo

VDBMS: A testbed facility for research in video database benchmarking

Real-world video-based applications require database technology that is capable of storing digital video in the form of video databases and providing content-based video search and retrieval. Methods for handling traditional data storage, query, search, retrieval, and presentation cannot be extended to provide this functionality. The VDBMS research initiative is motivated by the requirements of videobased applications to search and retrieve portions of video data based on content and by the need for testbed facilities to facilitate research in the area of video database management. In this paper we describe the VDBMS video database research platform, a system that supports comprehensive and efficient database management for digital video. Our fundamental concept is to provide a full range of functionality for video as a well-defined abstract database data type, with its own description, parameters, and applicable methods. Research problems that are addressed by VDBMS to support the handling of video data include MPEG7 standard multimedia content representation, algorithms for image-based shot detection, image processing techniques for extracting lowlevel visual features, a high-dimensional indexing technique to access the high-dimensional feature vectors extracted by image preprocessing, multimedia query processing and optimization, new query operators, real-time stream management, a search-based buffer management policy, and an access control model for selective, content-based access to streaming video. VDBMS also provides an environment for testing the correctness and scope of new video processing techniques, measuring the performance of algorithms in a standardized way, and comparing the performance of different implementations of an algorithm or component. We are ..

Multimedia Systems (2004) Multimedia Systems Digital Object Identifier (DOI) 10.1007/s00530-003-0129-9 © Springer-Verlag 2004 VDBMS: A testbed facility for research in video database benchmarking ⋆

Abstract. Real-world video-based applications require database technology that is capable of storing digital video in the form of video databases and providing content-based video search and retrieval. Methods for handling traditional data storage, query, search, retrieval, and presentation cannot be extended to provide this functionality. The VDBMS research initiative is motivated by the requirements of videobased applications to search and retrieve portions of video data based on content and by the need for testbed facilities to facilitate research in the area of video database management. In this paper we describe the VDBMS video database research platform, a system that supports comprehensive and efficient database management for digital video. Our fundamental concept is to provide a full range of functionality for video as a well-defined abstract database data type, with its ow

SoftLab -- A Virtual Laboratory for Computational Science

We describe a newly established research project called SoftLab in the area of computational science and computational engineering. The SoftLab project attempts to link physical laboratory experimentation with computer control and simulation to provide a virtual laboratory for computational science. We describe the overall project objectives and then introduce the three focus projects of SoftLab: Two Chemical Engineering SoftLabs (bioseparation and computational electronics) and a Mechanical Engineering SoftLab (computational mechanics). Preliminary results of our efforts are also described