127 research outputs found
Historical Reconstruction Reveals Recovery in Hawaiian Coral Reefs
Coral reef ecosystems are declining worldwide, yet regional differences in the trajectories, timing and extent of degradation highlight the need for in-depth regional case studies to understand the factors that contribute to either ecosystem sustainability or decline. We reconstructed social-ecological interactions in Hawaiian coral reef environments over 700 years using detailed datasets on ecological conditions, proximate anthropogenic stressor regimes and social change. Here we report previously undetected recovery periods in Hawaiian coral reefs, including a historical recovery in the MHI (∼AD 1400–1820) and an ongoing recovery in the NWHI (∼AD 1950–2009+). These recovery periods appear to be attributed to a complex set of changes in underlying social systems, which served to release reefs from direct anthropogenic stressor regimes. Recovery at the ecosystem level is associated with reductions in stressors over long time periods (decades+) and large spatial scales (>103 km2). Our results challenge conventional assumptions and reported findings that human impacts to ecosystems are cumulative and lead only to long-term trajectories of environmental decline. In contrast, recovery periods reveal that human societies have interacted sustainably with coral reef environments over long time periods, and that degraded ecosystems may still retain the adaptive capacity and resilience to recover from human impacts
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Beyond handover: supporting awareness for continuous coverage
Abstract Hospitals are required to operate as a continuous system because patient care cannot be temporarily suspended and handover is seen as a key method for enabling this. This paper reports a study of handover in a medical admissions unit. We draw on the notion of awareness as conceptualised within the Computer Supported Cooperative Work literature to explore the role played by a variety of cognitive artifacts in supporting continuous coverage. While such awareness is typically characterised as being ‘effortless’, our study reveals that maintaining awareness in a context such as the medical admissions unit is effortful due to invisible work. We suggest that the notion of awareness is beneficial for exploring the practices of continuous coverage because it moves attention away from the moment of handover, instead encouraging consideration of the variety of practices through which clinicians display their work to, and monitor the work of, colleagues on different shifts. We argue that efforts to support continuous coverage should focus on improving awareness by increasing the visibility of information
Selling issues with solutions: Igniting social intrapreneurship in for-profit organizations
We offer an explanation of the issue selling process when issues deviate from the dominant logic of organizations. Our main objective is to articulate the multiple ways in which socially oriented innovations can be legitimated in for-profit organizations through the work of bottom-up change agents, also known as social intrapreneurs. To unpack this multiplicity, we draw on both institutional theory and the framing perspective in social movements. Specifically, we propose how sellers may advance social issues with solutions by drawing on the logic composite
of both organizations and selling targets. By providing an account of the social issue selling process in for-profit organizations, we consider how the nature of an issue shapes selling efforts when it diverges from the dominant logic, and we shed light on how the content choices of sellers relate to the meaning systems of organizations and targets
The distribution and mitochondrial genotype of the hydroid Aglaophenia latecarinata is correlated with its pelagic Sargassum substrate type in the tropical and subtropical western Atlantic Ocean
© The Author(s), 2019. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Govindarajan, A. F., Cooney, L., Whittaker, K., Bloch, D., Burdorf, R. M., Canning, S., Carter, C., Cellan, S. M., Eriksson, F. A. A., Freyer, H., Huston, G., Hutchinson, S., McKeegan, K., Malpani, M., Merkle-Raymond, A., Ouellette, K., Petersen-Rockney, R., Schultz, M., & Siuda, A. N. S. The distribution and mitochondrial genotype of the hydroid Aglaophenia latecarinata is correlated with its pelagic Sargassum substrate type in the tropical and subtropical western Atlantic Ocean. Peerj, 7, (2019): e7814, doi:10.7717/peerj.7814.The pelagic brown macroalga Sargassum supports rich biological communities in the tropical and subtropical Atlantic region, including a variety of epiphytic invertebrates that grow on the Sargassum itself. The thecate hydroid Aglaophenia latecarinata is commonly found growing on some, but not all, Sargassum forms. In this study, we examined the relationship between A. latecarinata and its pelagic Sargassum substrate across a broad geographic area over the course of 4 years (2015–2018). The distribution of the most common Sargassum forms that we observed (Sargassum fluitans III and S. natans VIII) was consistent with the existence of distinct source regions for each. We found that A. latecarinata hydroids were abundant on both S. natans VIII and S. fluitans III, and also noted a rare observation of A. latecarinata on S. natans I. For the hydroids on S. natans VIII and S. fluitans III, hydroid mitochondrial genotype was strongly correlated with the Sargassum substrate form. We found significant population genetic structure in the hydroids, which was also consistent with the distributional patterns of the Sargassum forms. These results suggest that hydroid settlement on the Sargassum occurs in type-specific Sargassum source regions. Hydroid species identification is challenging and cryptic speciation is common in the Aglaopheniidae. Therefore, to confirm our identification of A. latecarinata, we conducted a phylogenetic analysis that showed that while the genus Aglaophenia was not monophyletic, all A. latecarinata haplotypes associated with pelagic Sargassum belonged to the same clade and were likely the same species as previously published sequences from Florida, Central America, and one location in Brazil (São Sebastião). A nominal A. latecarinata sequence from a second Brazilian location (Alagoas) likely belongs to a different species.This research was funded by Sea Education Association, Eckerd College, the New England Aquarium Conservation Action Fund and the Virginia Wellington Cabot Foundation. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript
Mesenchymal Stem Cell Graft Improves Recovery after Spinal Cord Injury in Adult Rats through Neurotrophic and Pro-Angiogenic Actions
Numerous strategies have been managed to improve functional recovery after spinal cord injury (SCI) but an optimal strategy doesn't exist yet. Actually, it is the complexity of the injured spinal cord pathophysiology that begets the multifactorial approaches assessed to favour tissue protection, axonal regrowth and functional recovery. In this context, it appears that mesenchymal stem cells (MSCs) could take an interesting part. The aim of this study is to graft MSCs after a spinal cord compression injury in adult rat to assess their effect on functional recovery and to highlight their mechanisms of action. We found that in intravenously grafted animals, MSCs induce, as early as 1 week after the graft, an improvement of their open field and grid navigation scores compared to control animals. At the histological analysis of their dissected spinal cord, no MSCs were found within the host despite their BrdU labelling performed before the graft, whatever the delay observed: 7, 14 or 21 days. However, a cytokine array performed on spinal cord extracts 3 days after MSC graft reveals a significant increase of NGF expression in the injured tissue. Also, a significant tissue sparing effect of MSC graft was observed. Finally, we also show that MSCs promote vascularisation, as the density of blood vessels within the lesioned area was higher in grafted rats. In conclusion, we bring here some new evidences that MSCs most likely act throughout their secretions and not via their own integration/differentiation within the host tissue
Watershed features and stream water quality: Gaining insight through path analysis in a Midwest urban landscape, U.S.A.
PD_NGSAtlas: a reference database combining next-generation sequencing epigenomic and transcriptomic data for psychiatric disorders
From Democratic Peace to Democratic Distinctiveness: A Critique of Democratic Exceptionalism in Peace and Conflict Studies
Incidence of Oronasal Fistula Formation After Nasoalveolar Molding and Primary Cleft Repair
A comparative study of linear measurements of facial skeleton using computed tomography and traditional cephalometry
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