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41.
Daniel C Dunn Caroline Jablonicky Guillermo O Crespo Douglas J McCauley David A Kroodsma Kristina Boerder Kristina M Gjerde Patrick N Halpin 《Fish and Fisheries》2018,19(4):729-739
Between 1950 and 1989, marine fisheries catch in the open‐ocean and deep‐sea beyond 200 nautical miles from shore increased by a factor of more than 10. While high seas catches have since plateaued, fishing effort continues to increase linearly. The combination of increasing effort and illegal, unreported and unregulated (IUU) fishing has led to overfishing of target stocks and declines in biodiversity. To improve management, there have been numerous calls to increase monitoring, control and surveillance (MCS). However, MCS has been unevenly implemented, undermining efforts to sustainably use high seas and straddling stocks and protect associated species and ecosystems. The United Nations General Assembly is currently negotiating a new international treaty for the conservation and sustainable use of biodiversity beyond national jurisdiction (BBNJ). The new treaty offers an excellent opportunity to address discrepancies in how MCS is applied across regional fisheries management organizations (RFMOs). This paper identifies ways that automatic identification system (AIS) data can inform MCS on the high seas and thereby enhance conservation and management of biodiversity beyond national jurisdictions. AIS data can be used to (i) identify gaps in governance to underpin the importance of a holistic scope for the new agreement; (ii) monitor area‐based management tools; and (iii) increase the capacity of countries and RFMOs to manage via the technology transfer. Any new BBNJ treaty should emphasize MCS and the role of electronic monitoring including the use of AIS data, as well as government–industry–civil society partnerships to ensure critically important technology transfer and capacity building. 相似文献
42.
43.
Christina A.D. Semeniuk Sophie Bourgeon Kristina D. Rothley 《Biological conservation》2009,142(8):1818-1829
Wildlife tourism alters the environmental conditions in which the focal animal lives, and it is therefore necessary to assess the ability of the animal to adjust to and persist in these novel conditions if the industry is to be sustainable. Here, we report on the physiological responses of southern stingrays (Dasyatis americana) which are the focus of intense marine provisioning-tourism in the Cayman Islands. Using stingrays from non-tourist sites about Grand Cayman as a basis for comparison, we show in this natural experiment that tourist-exposed stingrays exhibit hematological changes indicative of physiological costs of wildlife tourism. The novel conditions with which the stingrays must interact include non-natural food, higher injury rates (from boats, conspecifics and predators), and higher parasite loads (from crowding conditions). As a result of this year-round environment, stingrays display sub-optimal health: lower hematocrit, total serum protein concentrations, and oxidative stress (i.e., lower total antioxidant capacity combined with higher total oxidative status). Moreover, they show evidence of attenuation of the defense system: for tourist stingrays only, animals possessing both injuries and high parasite loads also exhibit lowest leukocrit, serum proteins and antioxidant potential, as well as differing proportions of differential leukocytes indicative of suppression (lymphocytes and heterophils) and down-regulation (eosinophils), thus suggesting that the physiological changes of tourist stingrays are in partial response to these stressors. While survival- and reproduction- quantification was not possible in this long-lived marine species, the physiological measures -situated within ecological context, indicate that the long-term health and survival of tourist stingrays have a significant probability of being affected. Consequently, management of the tourism attraction is essential. The indicators chosen in this study reflect general health indices and defense capabilities used across taxa, and represent a tradeoff between ease of collection/analysis and interpretation so that managers can continue the research for monitoring purposes. 相似文献
44.
Magdalene J. Seiler Robert B. Aramant† Mathias W. Seeliger‡ Ragnheidur Bragadottir§ Melissa Mahoney¶ Kristina Narfstrom 《Veterinary ophthalmology》2009,12(3):158-169
Purpose To investigate whether sheets of fetal retinal allografts can integrate into the dystrophic Abyssinian cat retina with progressive rod cone degeneration.
Methods Fetal retinal sheets (cat gestational day 42), incubated with BDNF microspheres, were transplanted to the subretinal space of four cats at an early disease stage. Cats were studied by fundus examinations, bilateral full-field flash ERGs, and indocyanine green and fluorescein angiograms up to 4 months following surgery. E42 donor and transplanted eyes were analyzed by histology and immunohistochemistry for retinal markers.
Results Funduscopy and angiography showed good integration of the transplants in two of four cats, including extension of host blood vessels into the transplant and some scarring in the host. In these two, transplants were found in the subretinal space with laminated areas, with photoreceptor outer segments in normal contacts with the host retinal pigment epithelium. In some areas, transplants appeared to be well-integrated within the host neural retina. Neither of these two cats showed functional improvement in ERGs. In the other two cats, only remnants of donor tissue were left. Transplants stained for all investigated cellular markers. No PKC immunoreactivity was detected in the fetal donor retina at E42, but developed in the 4-month-old grafts.
Conclusions Fetal sheet transplants can integrate well within a degenerating cat retina and develop good lamination of photoreceptors. Functional improvement was not demonstrated by ERG in cats with well-laminated grafts. Transplants need to be further evaluated in cat host retinas with a more advanced retinal degeneration using longer follow-up times. 相似文献
Methods Fetal retinal sheets (cat gestational day 42), incubated with BDNF microspheres, were transplanted to the subretinal space of four cats at an early disease stage. Cats were studied by fundus examinations, bilateral full-field flash ERGs, and indocyanine green and fluorescein angiograms up to 4 months following surgery. E42 donor and transplanted eyes were analyzed by histology and immunohistochemistry for retinal markers.
Results Funduscopy and angiography showed good integration of the transplants in two of four cats, including extension of host blood vessels into the transplant and some scarring in the host. In these two, transplants were found in the subretinal space with laminated areas, with photoreceptor outer segments in normal contacts with the host retinal pigment epithelium. In some areas, transplants appeared to be well-integrated within the host neural retina. Neither of these two cats showed functional improvement in ERGs. In the other two cats, only remnants of donor tissue were left. Transplants stained for all investigated cellular markers. No PKC immunoreactivity was detected in the fetal donor retina at E42, but developed in the 4-month-old grafts.
Conclusions Fetal sheet transplants can integrate well within a degenerating cat retina and develop good lamination of photoreceptors. Functional improvement was not demonstrated by ERG in cats with well-laminated grafts. Transplants need to be further evaluated in cat host retinas with a more advanced retinal degeneration using longer follow-up times. 相似文献
45.
Fish Physiology and Biochemistry - Sharks are not only threatened, but also have a low fecundity as they are being overfished. The shark family, Sphyrnidae, consists of nine species of which three... 相似文献
46.
Segner H Sundh H Buchmann K Douxfils J Sundell KS Mathieu C Ruane N Jutfelt F Toften H Vaughan L 《Fish physiology and biochemistry》2012,38(1):85-105
This brief review focuses on health and biological function as cornerstones of fish welfare. From the function-based point
of view, good welfare is reflected in the ability of the animal to cope with infectious and non-infectious stressors, thereby
maintaining homeostasis and good health, whereas stressful husbandry conditions and protracted suffering will lead to the
loss of the coping ability and, thus, to impaired health. In the first part of the review, the physiological processes through
which stressful husbandry conditions modulate health of farmed fish are examined. If fish are subjected to unfavourable husbandry
conditions, the resulting disruption of internal homeostasis necessitates energy-demanding physiological adjustments (allostasis/acclimation).
The ensuing energy drain leads to trade-offs with other energy-demanding processes such as the functioning of the primary
epithelial barriers (gut, skin, gills) and the immune system. Understanding of the relation between husbandry conditions,
allostatic responses and fish health provides the basis for the second theme developed in this review, the potential use of
biological function and health parameters as operational welfare indicators (OWIs). Advantages of function- and health-related
parameters are that they are relatively straightforward to recognize and to measure and are routinely monitored in most aquaculture
units, thereby providing feasible tools to assess fish welfare under practical farming conditions. As the efforts to improve
fish welfare and environmental sustainability lead to increasingly diverse solutions, in particular integrated production,
it is imperative that we have objective OWIs to compare with other production forms, such as high-density aquaculture. However,
to receive the necessary acceptance for legislation, more robust scientific backing of the health- and function-related OWIs
is urgently needed. 相似文献
47.
We report on screening tests of 66 extracts obtained from 35 marine sponge species from the Caribbean Sea (Curaçao) and from eight species from the Great Barrier Reef (Lizard Island). Extracts were prepared in aqueous and organic solvents and were tested for hemolytic, hemagglutinating, antibacterial and anti-acetylcholinesterase (AChE) activities, as well as their ability to inhibit or activate cell protein phosphatase 1 (PP1). The most interesting activities were obtained from extracts of Ircinia felix, Pandaros acanthifolium, Topsentia ophiraphidites, Verongula rigida and Neofibularia nolitangere. Aqueous and organic extracts of I. felix and V. rigida showed strong antibacterial activity. Topsentia aqueous and some organic extracts were strongly hemolytic, as were all organic extracts from I. felix. The strongest hemolytic activity was observed in aqueous extracts from P. acanthifolium. Organic extracts of N. nolitangere and I. felix inhibited PP1. The aqueous extract from Myrmekioderma styx possessed the strongest hemagglutinating activity, whilst AChE inhibiting activity was found only in a few sponges and was generally weak, except in the methanolic extract of T. ophiraphidites. 相似文献
48.
In agriculture, the principle of coexistence refers to a condition where different primary production systems can exist in the vicinity of each other, and can be managed in such a way that they affect each other as little as possible. Coexistence policies aim to ensure that farmers are able to freely grow the crops they choose—be they genetically engineered (GE), non-GE conventional, or organic. In the United States (US), the issue of coexistence has very recently come into sharp relief with the introduction of Roundup Ready® (RR) alfalfa, a landmark court decision in 2007 (Geertson v. Johanns), and subsequent governmental actions, including the first Environmental Impact Statement on a GE crop. By contrast, in 2003 the European Union (EU) created a policy to manage coexistence and to address economic harms that may be caused by contamination. We briefly review the EU framework as an instructive resource. This policy analysis then looks at the US organic industry and its standards with respect to GE before turning to the case of RR alfalfa. With a focus on the field trial stage and on environmental assessments prior to market approval, the case reveals numerous problems in the existing regulatory framework as it pertains to coexistence and prevention of contamination of organic products with GE material. The paper concludes with specific policy recommendations for creating a more robust coexistence policy in the US. 相似文献
49.
50.
The aim of the present study was to investigate indigenous fungal communities isolated from extreme environments (hypersaline waters of solar salterns and subglacial ice), for the production of metabolic compounds with selected biological activities: hemolysis, antibacterial, and acetylcholinesterase inhibition. In their natural habitats, the selected fungi are exposed to environmental extremes, and therefore the production of bioactive metabolites was tested under both standard growth conditions for mesophilic microorganisms, and at high NaCl and sugar concentrations and low growth temperatures. The results indicate that selected halotolerant and halophilic species synthesize specific bioactive metabolites under conditions that represent stress for non-adapted species. Furthermore, adaptation at the level of the chemical nature of the solute lowering the water activity of the medium was observed. Increased salt concentrations resulted in higher hemolytic activity, particularly within species dominating the salterns. The appearance of antibacterial potential under stress conditions was seen in the similar pattern of fungal species as for hemolysis. The active extracts exclusively affected the growth of the Gram-positive bacterium tested, Bacillus subtilis. None of the extracts tested showed inhibition of acetylcholinesterase activity. 相似文献