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141.
Living on the continental shelf edge: habitat use of juvenile shortfin makos Isurus oxyrinchus in the Great Australian Bight,southern Australia 下载免费PDF全文
Paul J. Rogers Charlie Huveneers Brad Page Simon D. Goldsworthy Micheal Coyne Andrew D. Lowther James G. Mitchell Laurent Seuront 《Fisheries Oceanography》2015,24(3):205-218
We used satellite telemetry data to investigate the movement patterns and habitat use of juvenile shortfin makos Isurus oxyrinchus (Lamnidae) tagged in the Great Australian Bight, southern Australia. Tracking durations ranged from 49–672 days and six deployments were > 1 year. During winter and spring, some shortfin makos migrated to the tropical NE Indian Ocean and Coral Sea, and the Subtropical Front region. One shortfin mako undertook an extended migration of 25 550 km across the Indian Ocean. Areas characterized by sea‐mounts in the NE Indian Ocean, the oceanic Subtropical Front region, and the continental shelf edge (200‐m depth) and slope canyons were visited by several sharks. Juvenile shortfin makos used the outer continental shelf, the shelf edge, the slope and oceanic waters during migrations and mostly exhibited fidelity in the mid‐outer shelf, the shelf edge and slope habitats characterized by high bathymetric relief and oceanographic frontal gradients. Our findings highlighted that the continental shelf and slope and associated submarine canyons of the Great Australian Bight represent ecologically important habitats for juvenile shortfin makos. The findings of this study will be pertinent during future management processes for this highly migratory species in this Southern Hemisphere region. 相似文献
142.
Pierre Laurent Suzanne Dunel-Erb Claudine Chevalier Jacques Lignon 《Fish physiology and biochemistry》1994,13(5):353-370
The aim of this work was to determine the kinetics of the dramatic development of the gill chloride cells (CCs) during adaptation
of the salmonid Oncorhynchus mykiss to an ion-poor environment.
To monitor cell division, the incorporation in the mitotic cell DNA of bromo-deoxyuridine (BrdUrd) was visualized with a monoclonal
antibody. The density of labelled nuclei was used as an index of cellular division (proliferation), concomitantly with morphometry
of phenotypic changes monitored with SEM.
In the filament epithelium, a phase of CC differentiation occurred within 12h after the transfer, followed by a delayed phase
of cell proliferation (48h). In the lamellar epithelium, the present study demonstrates the absence of cell proliferation
after ion-poor water transfer. The conclusion is that proliferation (mitosis) is important in the primary filament whereas
differentiation and migration (from the filament) is the main mechanism for the appearance of CCs on the secondary lamellae.
The present study suggests that cortisol promoted differentiation, but not division, of cells. CCs, presumably premature,
were stained by anti-cortisol monoclonal antibody indicating the presence of cortisol. No mature CCs were stained.
Growth hormone (oGH, ratGH) increased the rate of cell division both in lamellar and filament epithelium. 相似文献
143.
Lemaitre MP Laurent J Besson J Girard A Lippens C Muller C Vercheval J Ackerman M 《Science (New York, N.Y.)》1984,225(4658):171-172
The grille spectrometer observed the setting and rising sun 18 times during the Spacelab 1 mission. In addition to solar absorption lines, many of which had not been observed before, atmospheric spectral absorptions due to carbon monoxide and carbon dioxide were observed at heights tangent to the thermosphere (greater than 85 kilometers), and absorptions due to ozone, water, methane, and nitrous oxide were observed in the mesosphere (greater than 50 kilometers). The strongly coupled molecules NO-NO(2) and HC1-HF were observed as pairs in the stratosphere. Methane is presented as an example of the instrumental operations because of the characteristic aspect of the Q branch of its v(3) band. 相似文献
144.
The development of queen and worker phenotypes in ants has been believed to be largely determined from environmental effects. We provide evidence that the production of discrete phenotypes is also influenced by genetic interaction effects. During the development of eggs into adults, some patrilines among offspring of multiply mated Pogonomyrmex rugosus ant queens became more common in workers while others became overrepresented in queens. Controlled crosses showed that these changes stem from some parental genome combinations being compatible for producing one phenotype but less compatible for the other. Genetic interaction effects on caste may be maintained over evolutionary time because the fitness of an allele depends on its genetic background. 相似文献
145.
Post‐capture survival of whale sharks encircled in tuna purse‐seine nets: tagging and safe release methods 下载免费PDF全文
Lauriane Escalle Hilario Murua Justin Monin Amande Igor Arregui Pierre Chavance Alicia Delgado de Molina Daniel Gaertner Igaratza Fraile John David Filmalter Josu Santiago Fabien Forget Haritz Arrizabalaga Laurent Dagorn Bastien Merigot 《水产资源保护:海洋与淡水生态系统》2016,26(4):782-789
1. Whale shark, the world's largest fish, is believed to be particularly vulnerable owing to its biological characteristics (slow growth, late maturation, great longevity) and is listed as Vulnerable by IUCN and included in Appendix II of CITES. 2. Whale sharks are occasionally encircled in tropical tuna purse‐seine nets, throughout this global fishery. Although apparent immediate survival rates following encirclement and release have recently been assessed through scientific onboard observer programmes, a more rigorous methodology is still required for studying post‐released survival. 3. This work provides a method for applying pop‐up satellite tags and reports an enhanced release procedure for whale sharks. The first assessment of survival after release from purse‐seine nets involved six whale sharks tagged between May and September 2014 in the eastern tropical Atlantic Ocean. Five tags transmitted data: three popped up as programmed (after 30 days), while two surfaced prematurely (one after 21 and the other after 71 days (programmed to pop off after 30 and 90 days, respectively)) but showed no sign of unusual behaviour. 4. Overall, whale sharks survived at least 21 days (one at least 71 days) after release from purse‐seine nets. These observations based on five large individuals (total length > 8 m), suggest that whale sharks have a good chance of survival when released with the proposed method. 5. Additional tagging in this and other oceans, especially of juveniles which may be more sensitive to encirclement and release operations, is essential to further assess whale shark post‐release survival rates in tuna purse‐seine fisheries. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
146.
The discovery of an existing member of the Glypheidae, a family believed to have been extinct since the Eocene, may yield significant information on the evolution and classification of the decapod Crustacea. The single known specimen displays characters not apparent in fossil material, some of them perhaps representative of an ancestral decapod lineage, others reminiscent of the Astacidea and Thalassinidea. 相似文献
147.
The use of fish aggregating devices (FADs) by purse seine fisheries has come under increasing criticism for its potential deleterious impacts on tuna stocks, for high levels of by‐catch and threats to the biodiversity of tropical pelagic ecosystems. Here, we review the current state of scientific knowledge of this fishing technique and current management strategies. Our intent is to encourage objective discussion of the topic and highlight areas worthy of future research. We show that catching juvenile tuna around FADs does not necessarily result in overfishing of stocks, although more selective fishing techniques would likely help obtain higher yield. Levels of non‐tuna by‐catch are comparable to or less than in other commercial tuna fisheries and are primarily comprised of species that are not considered threatened. Accordingly, to minimize impacts on ecosystem balance, there is merit in considering that all species captured in purse seine fisheries (excluding vulnerable species such as turtles and sharks) should be retained, but the consequences of such a measure should be carefully examined before implementation. The take of vulnerable species could be further reduced by introduction of additional mitigation measures, but their potential benefits would be limited without parallel efforts with other gears. Finally, there is no unequivocal empirical evidence that FADs represent an ‘ecological trap’ that inherently disrupts tuna biology although further research should focus on this issue. We encourage RFMOs to expand and improve their FAD management plans. Under appropriate management regimes, FAD fishing could be an ecologically and economically sensible fishing method. 相似文献
148.
Behr S Trumel C Cauzinille L Palenché F Braun JP 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2006,20(3):657-662
This study was performed to investigate the diagnostic relevance of cerebrospinal fluid (CSF) high resolution electrophoresis. The laboratory technique was applied to 100 paired samples of canine CSF and serum, with paired samples tested during the same analytical run, as recommended in human medicine. Ninety four of the dogs had a neurological disease and 6 healthy dogs served as a control group. A strong linear correlation between CSF total protein concentration and the albumin quota (AQ) was found in the control group and in the inflammatory (infectious or noninfectious), neoplastic, and miscellaneous groups: AQ = 0.015 CSF total protein--0.102, r = 0.990. This correlation suggests that an increased CSF total protein concentration can be an indicator of blood brain barrier dysfunction. The highest median AQ value was found in the aseptic suppurative meningitis group, but no statistical differences were found between this and the other groups. The AQ, calculated with this technique, did not provide any additional information. Moreover, although unexpected, the electrophoretic profiles were not characteristic of any particular disease. In conclusion, this study did not confirm high resolution electrophoresis of paired CSF and serum samples to be a valuable ancillary diagnostic tool for canine neurological diseases. 相似文献
149.
150.
Garosi L 《Journal of Feline Medicine and Surgery》2012,14(1):85-93
PRACTICAL RELEVANCE: Neurological causes of lameness are infrequently seen in cats but they are an important consideration when an obvious orthopaedic cause cannot be identified. Monoparetic cats are also frequently presented for veterinary investigation with the main complaint being lameness. CLINICAL CHALLENGES: Neurological causes of lameness may be difficult to determine without access to advanced imaging modalities, electrodiagnostics or cerebrospinal fluid analysis. AUDIENCE: This review, aimed at all veterinarians who treat cats, sets out to describe the specific approach to cats with lameness that cannot be attributed to an orthopaedic cause. It describes the diagnosis and management of the most common neurological conditions responsible for lameness or monoparesis in cats. 相似文献