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Melissa R. Cronin Julia E. Amaral Alexis M. Jackson Jennifer Jacquet Katherine L. Seto Donald A. Croll 《Fish and Fisheries》2023,24(1):56-70
The incidental capture by marine fisheries as bycatch poses a global threat to pelagic sharks and rays. In large, industrialized fisheries that often operate in areas beyond national jurisdiction, at least 22 threatened species of pelagic elasmobranchs are caught as bycatch, representing the majority of megafauna bycatch in tuna fisheries. Here, we investigate (1) the efficacy of the current policies of the five tuna-related Regional Fisheries Management Organizations (tRFMOs) in mitigating elasmobranch bycatch, (2) data needed to better assess the amount and impact of elasmobranch bycatch and (3) the research necessary for the adoption of new policies. We found that tRFMOs have adopted 34 active policies that address pelagic elasmobranch bycatch. However, most policies (~76%, n = 26) are unlikely to avoid or minimize elasmobranch bycatch. Instead, most policies focus on mitigating post-capture mortality via remediation and requiring or encouraging research and data collection. Despite the emphasis on research mandates, we find that the existence of research was not related to policy adoption, suggesting that lack of research has not historically prohibited policymaking. Overall, we suggest that current research and data transparency, though perhaps not necessary for policy adoption, are not sufficient to adequately evaluate the population-level impacts of bycatch on many elasmobranch species in tRFMO-managed fisheries. Given these results, we recommend a precautionary approach that involves reforms in tRFMO voting processes to facilitate the adoption of binding requirements for elasmobranch catch limits, bycatch avoidance, pre- and post-capture handling and release modifications and protection of areas important to threatened pelagic elasmobranchs. 相似文献
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Berriman M Ghedin E Hertz-Fowler C Blandin G Renauld H Bartholomeu DC Lennard NJ Caler E Hamlin NE Haas B Böhme U Hannick L Aslett MA Shallom J Marcello L Hou L Wickstead B Alsmark UC Arrowsmith C Atkin RJ Barron AJ Bringaud F Brooks K Carrington M Cherevach I Chillingworth TJ Churcher C Clark LN Corton CH Cronin A Davies RM Doggett J Djikeng A Feldblyum T Field MC Fraser A Goodhead I Hance Z Harper D Harris BR Hauser H Hostetler J Ivens A Jagels K Johnson D Johnson J Jones K Kerhornou AX Koo H 《Science (New York, N.Y.)》2005,309(5733):416-422
African trypanosomes cause human sleeping sickness and livestock trypanosomiasis in sub-Saharan Africa. We present the sequence and analysis of the 11 megabase-sized chromosomes of Trypanosoma brucei. The 26-megabase genome contains 9068 predicted genes, including approximately 900 pseudogenes and approximately 1700 T. brucei-specific genes. Large subtelomeric arrays contain an archive of 806 variant surface glycoprotein (VSG) genes used by the parasite to evade the mammalian immune system. Most VSG genes are pseudogenes, which may be used to generate expressed mosaic genes by ectopic recombination. Comparisons of the cytoskeleton and endocytic trafficking systems with those of humans and other eukaryotic organisms reveal major differences. A comparison of metabolic pathways encoded by the genomes of T. brucei, T. cruzi, and Leishmania major reveals the least overall metabolic capability in T. brucei and the greatest in L. major. Horizontal transfer of genes of bacterial origin has contributed to some of the metabolic differences in these parasites, and a number of novel potential drug targets have been identified. 相似文献
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Pain A Renauld H Berriman M Murphy L Yeats CA Weir W Kerhornou A Aslett M Bishop R Bouchier C Cochet M Coulson RM Cronin A de Villiers EP Fraser A Fosker N Gardner M Goble A Griffiths-Jones S Harris DE Katzer F Larke N Lord A Maser P McKellar S Mooney P Morton F Nene V O'Neil S Price C Quail MA Rabbinowitsch E Rawlings ND Rutter S Saunders D Seeger K Shah T Squares R Squares S Tivey A Walker AR Woodward J Dobbelaere DA Langsley G Rajandream MA McKeever D Shiels B Tait A Barrell B Hall N 《Science (New York, N.Y.)》2005,309(5731):131-133
Theileria annulata and T. parva are closely related protozoan parasites that cause lymphoproliferative diseases of cattle. We sequenced the genome of T. annulata and compared it with that of T. parva to understand the mechanisms underlying transformation and tropism. Despite high conservation of gene sequences and synteny, the analysis reveals unequally expanded gene families and species-specific genes. We also identify divergent families of putative secreted polypeptides that may reduce immune recognition, candidate regulators of host-cell transformation, and a Theileria-specific protein domain [frequently associated in Theileria (FAINT)] present in a large number of secreted proteins. 相似文献
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Three carbonaceous chondrites were examined for water-extractable amino acids. The Murchison Murray specimens were found to be of similar amino acid composition. This similarity suggests that these amino acids in are indigenous to type II carbonaceous chondrites. The Allende (type III) carbonaceous chondrite was found to be essentially devoid of amino acids on the basis of on identical analysis. 相似文献
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Sorenmo K Duda L Barber L Cronin K Sammarco C Usborne A Goldschmidt M Shofer F 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2000,14(4):395-398
Standard treatments for canine hemangiosarcoma include surgery and chemotherapy with doxorubicin, but in spite of treatment most dogs with this disease die within 6 months of diagnosis. Tumor growth and metastasis are angiogenesis dependent. Antiangiogenic drugs such as minocycline may provide therapeutic benefits in cancer patients. The purpose of this prospective study was to evaluate the efficacy of chemotherapy with doxorubicin and minocycline, an antiangiogenic agent, in dogs with hemangiosarcoma. Eighteen dogs with histologically confirmed hemangiosarcoma of any stage were treated with doxorubicin, cyclophosphamide, and minocycline. Complete staging was performed before and during the treatment period to assess remission status and response to therapy. No statistically significant difference was found in survival between the dogs treated with chemotherapy and minocycline, and historical controls consisting of dogs that received chemotherapy alone. Postmortem examination revealed widespread metastasis, suggesting that minocycline is ineffective as a single antiangiogenic agent in canine hemangiosarcoma. 相似文献
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OBJECTIVE: To evaluate the efficacy of a reusable plastic model mimicking the anatomy and hemodynamics of the canine female genital tract for teaching basic surgical skills and ovariohysterectomy. SAMPLE POPULATION: 40 veterinary students of the class of 1998. STUDY DESIGN: Prospective study. METHODS: Students'confidence level and experience in private practice was evaluated via questionnaire before training. Students in 2 groups performed an ovariohysterectomy on cadavers (group C, n = 20) or on the model (Group M, n = 20) for 2 hours. Students' psychomotor and basic surgical skills were objectively assessed by the following tests: ligation of a foam cylinder, passing a needle through the eyelets of an electronic suture board, and ligating latex tubing. Results were compared before and after training and within and between groups. The ability of students to perform an ovariohysterectomy in a live dog after training was compared between groups with a scoring system. RESULTS: Students in both groups had similar surgical experience and basic skills before training. The results of the psychomotor and basic surgical skills tests were better in group M after training than group C. The improvement of each student in performing these tasks also increased when students were trained with the model. Scores assigned to students performing an ovariohysterectomy in a live dog were higher in group M (31.45 +/- 1.15) than in group C (20.7 +/- 1.42). CONCLUSION: The model was more effective than cadavers in teaching basic surgical skills and ovariohysterectomy in dogs. 相似文献