42,289 research outputs found
A simple method for detecting chaos in nature
Chaos, or exponential sensitivity to small perturbations, appears everywhere
in nature. Moreover, chaos is predicted to play diverse functional roles in
living systems. A method for detecting chaos from empirical measurements should
therefore be a key component of the biologist's toolkit. But, classic
chaos-detection tools are highly sensitive to measurement noise and break down
for common edge cases, making it difficult to detect chaos in domains, like
biology, where measurements are noisy. However, newer tools promise to overcome
these limitations. Here, we combine several such tools into an automated
processing pipeline, and show that our pipeline can detect the presence (or
absence) of chaos in noisy recordings, even for difficult edge cases. As a
first-pass application of our pipeline, we show that heart rate variability is
not chaotic as some have proposed, and instead reflects a stochastic process in
both health and disease. Our tool is easy-to-use and freely available
2012 Annual report
The CGIAR Research Program on Aquatic Agricultural Systems is a multi-year research initiative launched in July 2011. It is designed to pursue community-based approaches to agricultural research and development that target the poorest and most vulnerable rural households in aquatic agricultural systems. Led by WorldFish, a member of the CGIAR Consortium, the program is partnering with diverse organizations working at local, national and global levels to help achieve impacts at scale
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What is a Freestanding Emergency Department? Definitions Differ Across Major United States Data Sources
Introduction: Despite the growing number of freestanding emergency departments (FSED) in the United States (US), FSED definitions differ across major US data sources of healthcare facilities and use. We compare these sources and propose a universal definition of FSED (and its two major types) to improve communications regarding these facilities and their patients.Methods: We collected definitions of FSEDs from 11 national data sources using their websites, email, and telephone communications. For each source, we asked how they define FSEDs, whether being open 24/7 is a requirement to be called an ED, and whether they maintain a dataset of FSEDs.Results: Definitions varied across the data sources. All sources recognize FSEDs in their definitions, regardless of type; only one (the National Health Intervew Survey) does not differentiate them from other EDs. Five of the 11 sources (45%) omit autonomous FSEDs from their definitions and do not separately identify satellite FSEDs from their affiliated hospitals. One source does separately identify satellite FSEDs from their affiliated hospitals, but also omits autonomous FSEDs. Furthermore, three of the 11 sources (27%) do not require being open 24/7, while all others (73%) employ this criterion. Six of the 11 (55%) maintain datasets of FSEDs using their definition.Conclusion: As FSEDs continue to change the landscape of emergency care, it is important that they also be represented in national ED data sources. The current differences in the definition of an FSED make it difficult to provide accurate and longitudinal analysis for these facilities and patients who receive services at these facilities. We propose a universal definition of FSEDs as described by both the American College of Emergency Physicians and the National Emergency Department Inventory. Implementing a standard definition would facilitate a more accurate representation of FSEDs in national data sources and enhance ongoing efforts to improve the quality of emergency care delivered in FSEDs
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