74 research outputs found
Chick Embryo Partial Ischemia Model: A New Approach to Study Ischemia Ex Vivo
Background: Ischemia is a pathophysiological condition due to blockade in blood supply to a specific tissue thus damaging the physiological activity of the tissue. Different in vivo models are presently available to study ischemia in heart and other tissues. However, no ex vivo ischemia model has been available to date for routine ischemia research and for faster screening of anti-ischemia drugs. In the present study, we took the opportunity to develop an ex vivo model of partial ischemia using the vascular bed of 4th day incubated chick embryo.
Methodology/Principal Findings: Ischemia was created in chick embryo by ligating the right vitelline artery using sterile surgical suture. Hypoxia inducible factor- 1 alpha (HIF-1a), creatine phospho kinase-MB and reactive oxygen species in animal tissues and cells were measured to confirm ischemia in chick embryo. Additionally, ranolazine, N-acetyl cysteine and trimetazidine were administered as an anti-ischemic drug to validate the present model. Results from the present study depicted that blocking blood flow elevates HIF-1a, lipid peroxidation, peroxynitrite level in ischemic vessels while ranolazine administration partially attenuates ischemia driven HIF-1a expression. Endothelial cell incubated on ischemic blood vessels elucidated a higher level of HIF-1a expression with time while ranolazine treatment reduced HIF-1a in ischemic cells. Incubation of caprine heart strip on chick embryo ischemia model depicted an elevated creatine phospho kinase-MB activity under ischemic condition while histology of the treated heart sections evoked edema and disruption of myofibril structures.
Conclusions/Significance: The present study concluded that chick embryo partial ischemia model can be used as a novel ex vivo model of ischemia. Therefore, the present model can be used parallel with the known in vivo ischemia models in understanding the mechanistic insight of ischemia development and in evaluating the activity of anti-ischemic drug.status: publishe
Bringing analysis of gender and social–ecological resilience together in small-scale fisheries research: Challenges and opportunities
The demand for gender analysis is now increasingly orthodox in natural resource programming, including that for small-scale fisheries. Whilst the analysis of social–ecological resilience has made valuable contributions to integrating social dimensions into research and policy-making on natural resource management, it has so far demonstrated limited success in effectively integrating considerations of gender equity. This paper reviews the challenges in, and opportunities for, bringing a gender analysis together with social–ecological resilience analysis in the context of small-scale fisheries research in developing countries. We conclude that rather than searching for a single unifying framework for gender and resilience analysis, it will be more effective to pursue a plural solution in which closer engagement is fostered between analysis of gender and social-ecological resilience whilst preserving the strengths of each approach. This approach can make an important contribution to developing a better evidence base for small-scale fisheries management and policy
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Destructive fishing: An expert-driven definition and exploration of this quasi-concept
Data availability statement:
Data that breaches the anonymity of responses in this study cannot be made available. Some anonymised and summary data can be found in the Supplementary Information.Data Availability Statement: Data that breaches the anonymity of responses in this study cannot be made available. Some anonymized and summary data can be found in the Supplementary Information.Code Availability Statement: Code for the figures and certain analyses used in this manuscript can be found at https://github.com/arlie-m/destructive_fishing_defintion_delphi.Supporting Information is available online at: https://conbio.onlinelibrary.wiley.com/doi/10.1111/conl.13015#support-information-section .Numerous policy and international frameworks consider that “destructive fishing” hampers efforts to reach sustainability goals. Though ubiquitous, “destructive fishing” is undefined and therefore currently immeasurable. Here we propose a definition developed through expert consultation: “Destructive fishing is any fishing practice that causes irrecoverable habitat degradation, or which causes significant adverse environmental impacts, results in long-term declines in target or nontarget species beyond biologically safe limits and has negative livelihood impacts.” We show strong stakeholder support for a definition, consensus on many biological and ecological dimensions, and no clustering of respondents from different sectors. Our consensus definition is a significant step toward defining sustainable fisheries goals and will help interpret and implement global political commitments which utilize the term “destructive fishing.” Our definition and results will help reinforce the Food and Agricultural Organization's Code of Conduct and meaningfully support member countries to prohibit destructive fishing practices.Cambridge Conservation Initiative. Grant Number: CCI-05-20-009;
Helmholtz Institute for Functional Marine Biodiversity (HIFMB) at the University of Oldenburg;
Brunel University London;
Alfred-Wegener-Institute for Polar and Marine Research;
Arcadia;
Rothschild Foundation;
A.G. Leventis Foundation;
Isaac Newton Trust;
Prince Albert II of Monaco Foundation
Destructive fishing : an expert‐driven definition and exploration of this quasi‐concept
Numerous policy and international frameworks consider that “destructive fishing” hampers efforts to reach sustainability goals. Though ubiquitous, “destructive fishing” is undefined and therefore currently immeasurable. Here we propose a definition developed through expert consultation: “Destructive fishing is any fishing practice that causes irrecoverable habitat degradation, or which causes significant adverse environmental impacts, results in long-term declines in target or nontarget species beyond biologically safe limits and has negative livelihood impacts.” We show strong stakeholder support for a definition, consensus on many biological and ecological dimensions, and no clustering of respondents from different sectors. Our consensus definition is a significant step toward defining sustainable fisheries goals and will help interpret and implement global political commitments which utilize the term “destructive fishing.” Our definition and results will help reinforce the Food and Agricultural Organization's Code of Conduct and meaningfully support member countries to prohibit destructive fishing practices
fisheries and tourism social economic and ecological trade offs in coral reef systems
Coastal communities are exerting increasingly more pressure on coral reef ecosystem services in the Anthropocene. Balancing trade-offs between local economic demands, preservation of traditional values, and maintenance of both biodiversity and ecosystem resilience is a challenge for reef managers and resource users. Consistently, growing reef tourism sectors offer more lucrative livelihoods than subsistence and artisanal fisheries at the cost of traditional heritage loss and ecological damage. Using a systematic review of coral reef fishery reconstructions since the 1940s, we show that declining trends in fisheries catch and fish stocks dominate coral reef fisheries globally, due in part to overfishing of schooling and spawning-aggregating fish stocks vulnerable to exploitation. Using a separate systematic review of coral reef tourism studies since 2013, we identify socio-ecological impacts and economic opportunities associated to the industry. Fisheries and tourism have the potential to threaten the ecological stability of coral reefs, resulting in phase shifts toward less productive coral-depleted ecosystem states. We consider whether four common management strategies (unmanaged commons, ecosystem-based management, co-management, and adaptive co-management) fulfil ecological conservation and socioeconomic goals, such as living wage, job security, and maintenance of cultural traditions. Strategies to enforce resource exclusion and withhold traditional resource rights risk social unrest; thus, the coexistence of fisheries and tourism industries is essential. The purpose of this chapter is to assist managers and scientists in their responsibility to devise implementable strategies that protect local community livelihoods and the coral reefs on which they rely
The importance of qualitative social research for effective fisheries management
© 2016 Over recent decades it has become widely accepted that managing fisheries resources means managing human behaviour, and so understanding social and economic dynamics is just as important as understanding species biology and ecology. Until recently, fisheries managers and researchers have struggled to develop effective methods and data for social and economic analysis that can integrate with the predominantly biological approaches to fisheries management. The field is now growing fast, however, and globally, researchers are developing and testing new methods. This paper uses three divergent case studies to demonstrate the value of using qualitative social science approaches to complement more conventional quantitative methods to improve the knowledge base for fisheries management. In all three cases, qualitative interview and document review methods enabled broad surveying to explore the research questions in particular contexts and identified where quantitative tools could be most usefully applied. In the first case (the contribution of commercial fisheries to coastal communities in eastern Australia), a wellbeing analysis identified the social benefits from particular fisheries, which can be used to identify the social impacts of different fisheries management policies. In the second case (a gender analysis of fisheries of small islands in the Pacific), analysis outlined opportunities and constraints along fisheries supply chains, illuminated factors inhibiting community development and identified ecological factors that are typically overlooked in conventional fisheries management. In the third case (sea cucumber fisheries in Papua New Guinea), an interactive governance analysis assessed how well fisheries management tools fit the ecological, social and economic reality of the fishery and the trade in its products, including market influences and stakeholder values. The qualitative approach adopted in these three case studies adds a new dimension to understanding fisheries that is not possible with a focus solely on quantitative data. With the development of new policies on release programs (stock enhancement, restocking) and artificial reefs, and the momentum to use these interventions from recreational fishing groups, the qualitative approach will provide an important contribution to understanding their wider costs and benefits
Seascape shadows: Life in the ruins of the edible bird's nest harvest in northern Palawan, the Philippines
The intensifying extraction, privatization, and conservation of maritime spaces are transforming seascapes globally. Amidst rapid coastal change and the ambiguous reconfiguration of oceans as frontiers are coastal dwellers who occupy the shadows of these seascapes. In contrast to the capture of high-profile marine species, the harvest of the edible nests of balinsasayaw (swiftlet, Aerodramus fuciphagus) remains largely concealed at the interstitial spaces between land, coast, and sea. In the Philippines, harvesters known as busyador negotiate social relations, political networks, and karst systems to extract these lucrative nests. Despite the nest industry growing in value in Southeast Asia, we show how the busyador struggle in precarious social relations and spaces peripheral to coastal governance in northern Palawan Island. Building on the concept of ‘seascape assemblages’, we emphasize the importance of the less visible human-nonhuman relations that shape the nest harvest and trade. We trace the marginal social histories of the balinsasayaw by highlighting the precarious nature of the harvest, revealing how the busyador are subject to unfair working conditions, dispossession, and violence. We argue that as state actors and local elites reconfigure oceans as frontiers for development and conservation, struggles over labour and tenure rights, livelihood opportunities, and justice at sea are disregarded
Interactive Governance Analysis of the Beche-de-Mer 'Fish Chain' from Papua New Guinea to Asian Markets
The objective of this study was to conduct a governance analysis that will assist the National Fisheries Authority (NFA) and other stakeholders to grasp the factors influencing the effectiveness of the new Management Plan
Ranibizumab pretreatment in diabetic vitrectomy:a pilot randomised controlled trial (the RaDiVit study)
PURPOSE: Our aim was to evaluate the impact of intravitreal ranibizumab pretreatment on the outcome of vitrectomy surgery for advanced proliferative diabetic retinopathy. The objective was to determine the feasibility of a subsequent definitive trial and estimate the effect size and variability of the outcome measure.
PATIENTS AND METHODS: We performed a pilot randomised double-masked single-centre clinical trial in 30 participants with tractional retinal detachment associated with proliferative diabetic retinopathy. Seven days prior to vitrectomy surgery, participants were randomly allocated to receive either intravitreal ranibizumab (Lucentis, Novartis Pharmaceuticals UK Ltd, Frimley, UK) or subconjunctival saline (control). The primary outcome was best-corrected visual acuity 12 weeks following surgery.
RESULTS: At 12 weeks, the mean (SD) visual acuity was 46.7 (25) ETDRS letters in the control group and 52.6 (21) letters in the ranibizumab group. Mean visual acuity improved by 14 (31) letters in the control group and by 24 (27) letters in the ranibizumab group. We found no difference in the progression of tractional retinal detachment prior to surgery, the duration of surgery, or its technical difficulty. Vitreous cavity haemorrhage persisted at 12 weeks in two of the control group but none of the ranibizumab group.
CONCLUSION: Ranibizumab pretreatment may improve the outcome of vitrectomy surgery for advanced proliferative diabetic retinopathy by reducing the extent of post-operative vitreous cavity haemorrhage. However, the effect size appears to be modest; we calculate that a definitive study to establish a minimally important difference of 5.9 letters at a significance level of P<0.05 would require 348 subjects in each arm
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