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1.
Data Sci J ; 17: 15, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-33101400

RESUMO

Scientific data stewardship is an important part of long-term preservation and the use/reuse of digital research data. It is critical for ensuring trustworthiness of data, products, and services, which is important for decision-making. Recent U.S. federal government directives and scientific organization guidelines have levied specific requirements, increasing the need for a more formal approach to ensuring that stewardship activities support compliance verification and reporting. However, many science data centers lack an integrated, systematic, and holistic framework to support such efforts. The current business- and process-oriented stewardship frameworks are too costly and lengthy for most data centers to implement. They often do not explicitly address the federal stewardship requirements and/or the uniqueness of geospatial data. This work proposes a data-centric conceptual enterprise framework for managing stewardship activities, based on the philosophy behind the Plan-Do-Check-Act (PDCA) cycle, a proven industrial concept. This framework, which includes the application of maturity assessment models, allows for quantitative evaluation of how organizations manage their stewardship activities and supports informed decision-making for continual improvement towards full compliance with federal, agency, and user requirements.

2.
Proc Natl Acad Sci U S A ; 104(12): 4820-3, 2007 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-17360360

RESUMO

Despite early speculation to the contrary, all tropical forests studied to date display seasonal variations in the presence of new leaves, flowers, and fruits. Past studies were focused on the timing of phenological events and their cues but not on the accompanying changes in leaf area that regulate vegetation-atmosphere exchanges of energy, momentum, and mass. Here we report, from analysis of 5 years of recent satellite data, seasonal swings in green leaf area of approximately 25% in a majority of the Amazon rainforests. This seasonal cycle is timed to the seasonality of solar radiation in a manner that is suggestive of anticipatory and opportunistic patterns of net leaf flushing during the early to mid part of the light-rich dry season and net leaf abscission during the cloudy wet season. These seasonal swings in leaf area may be critical to initiation of the transition from dry to wet season, seasonal carbon balance between photosynthetic gains and respiratory losses, and litterfall nutrient cycling in moist tropical forests.


Assuntos
Folhas de Planta/anatomia & histologia , Folhas de Planta/crescimento & desenvolvimento , Estações do Ano , Árvores/anatomia & histologia , Árvores/crescimento & desenvolvimento , Brasil , Geografia , Tamanho do Órgão , Folhas de Planta/efeitos da radiação , Chuva , Comunicações Via Satélite/instrumentação , Luz Solar , Fatores de Tempo , Árvores/efeitos da radiação
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