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Vincenzo Alterio Emma Langella Giuseppina De Simone Simona Maria Monti 《Marine drugs》2015,13(4):1688-1697
The Carbon Concentration Mechanism (CCM) allows phytoplakton species to accumulate the dissolved inorganic carbon (DIC) necessary for an efficient photosynthesis even under carbon dioxide limitation. In this mechanism of primary importance for diatoms, a key role is played by carbonic anhydrase (CA) enzymes which catalyze the reversible hydration of CO2, thus taking part in the acquisition of inorganic carbon for photosynthesis. A novel CA, named CDCA1, has been recently discovered in the marine diatom Thalassiosira weissflogii. CDCA1 is a cambialistic enzyme since it naturally uses Cd2+ as catalytic metal ion, but if necessary can spontaneously exchange Cd2+ to Zn2+. Here, the biochemical and structural features of CDCA1 enzyme will be presented together with its putative biotechnological applications for the detection of metal ions in seawaters. 相似文献
43.
Stepwise function of natural growth for Scylla serrata in East Africa: a valuable tool for assessing growth of mud crabs in aquaculture 下载免费PDF全文
Per‐Olav Moksnes David Oersted Mirera Emma Björkvik Muumin Iddi Hamad Humphrey Matalu Mahudi Daniel Nyqvist Narriman Jiddawi Max Troell 《Aquaculture Research》2015,46(12):2938-2953
Predicting growth is critical in aquaculture, but models of growth are largely missing for mud crab species. Here, we present the first model of natural growth in juvenile and adult mud crabs Scylla serrata from East Africa using a stepwise growth function based on data on intermoult periods and growth at moult from field mark‐recapture, pond and laboratory studies. The results showed a sigmoid growth pattern in carapace width and suggest that S. serrata in East Africa will reach 300 g and sexual maturity ~9.9 months after settlement, and a commercial size of 500 g after 12.4 months. Analyses of the literature identified several issues with the common praxis to compare standard growth measures between aquaculture studies with different initial size or growing periods. Using the new growth function to estimate the proportional difference between modelled and obtained growth as an alternative method, we show that growth rates of S. serrata cultured in cage systems, which are dominant in East Africa, was <40% of the estimated natural growth and growth obtained in pond systems. The analysis also indicated that growth rates of S. serrata in Southeast Asia was over 50% higher compared with similar culture systems in East Africa, and that different species of mud crabs had large differences in growth rates. This study shows that growth in the present mud crab aquaculture systems in East Africa is below their expected potential. Further work is needed to identify the factors behind this observation. 相似文献
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Bauer NB Bassett H O'Neill EJ Acke E 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2006,35(1):123-125
A 6-year-old, intact female, Labrador Retriever/Terrier cross was presented to the University Veterinary Hospital, University College Dublin with a 3-week history of therapy-resistant cervical pain and intermittent fever. Physical examination findings included marked cervical pain resulting in neck extension and vocalization. Examination of the CSF revealed mild pleocytosis (total nucleated cells = 0.009 x 10(9)/L, reference interval <0.005 x 10(9)/L). Cytocentrifuged preparations of the CSF were of low cellularity, containing predominantly macrophages and occasional small lymphocytes. Several small- to medium-sized fragments of a slightly granular, amorphous, eosinophilic substance were observed. The majority of mononuclear cells were located within this material, in small groups of 3-13 cells. The amorphous foamy material stained positive with Luxol fast blue, suggestive of myelin-like material. The dog was euthanized and postmortem examination revealed intervertebral disk protrusion between C2 and C3. Hematoxylin- and Luxol fast blue-stained histopathologic sections of brain and spinal cord revealed only mild hemorrhage. The extracellular material in the CSF of this dog may have been caused by myelin degeneration or leakage of phospholipids from damaged cells. Because no histologic evidence of demyelination was observed with the disk extrusion, the myelin-like material in this case was thought to be the product of phospholipid breakdown from damaged cellular membranes. Three cases of dogs with spinal cord disease and myelin-like material in the CSF have been reported previously. The clinical significance of this finding is still unknown. 相似文献
46.
Damaris Godinez-Vidal Mario Rocha-Sosa Edgar B. Sepúlveda-García Joel Lara-Reyna Reyna Rojas-Martínez Emma Zavaleta-Mejía 《European journal of plant pathology / European Foundation for Plant Pathology》2008,120(3):299-303
We tested the hypothesis that PAL activity in chilli plants CM-334 inoculated with Nacobbus aberrans (Na) alone or in combination with Phytophthora capsici (Pc), is lower than in those inoculated only with Pc. At 21 days after nematode inoculation, inoculated plants showed a significant
(P < 0.01) reduction of 48% in PAL activity compared to those non-inoculated in two separate experiments. In two other tests,
where plants were inoculated with the oomycete 21 days after inoculation with the nematode, PAL activity at 2, 4, 6, 8 and
24 h after inoculation with Pc was significantly higher (Tukey, P < 0.01) in plants inoculated only with Pc than in plants inoculated only with Na or both pathogens (Na+Pc). 相似文献
47.
Over half of the endangered species in the United States depend on private lands for habitat. In 1982, Congress amended the Endangered Species Act (ESA) to address the conservation of endangered species on private lands through the introduction of Habitat Conservation Plans (HCPs). HCPs enable landowners to comply with the ESA and can foster creative partnerships between the federal government and local stakeholders. Researchers have investigated the scientifically biological merits of HCPs, but comparatively little attention has been given to social aspects despite an emphasis on stakeholder involvement in HCPs. We explore stakeholder perceptions of HCP development through 19 semi-structured key informant interviews. Findings include the influence of interpersonal themes, shared understanding and capacity on process outcomes, and the importance of the external context in which HCP development occurs. Our research highlights the central role of understanding social dimensions to achieve the desired outcomes from collaborative conservation planning processes. 相似文献
48.
Method comparison and generation of plasma biochemistry RIs for the White rhinoceros on a point‐of‐care and wet chemistry analyzer 下载免费PDF全文
49.
Emma J. STOKES 《Integrative zoology》2010,5(4):363-377
Wild tigers are in a critical state with an estimated population decline of more than 95% over the past century. Improving the capacity and effectiveness of law enforcement in reducing poaching of tigers is an immediate priority to secure remaining wild populations in source sites. From 2008–2010, standardized patrol-based law enforcement monitoring (LEM) was established under the Tigers Forever Program across 8 key tiger sites in order to improve and evaluate law enforcement interventions. Patrol-based monitoring has the distinct advantage of providing regular and rapid information on illegal activities and ranger performance, although, until recently, it has received relatively little scrutiny from the conservation community. The present paper outlines a framework for implementation of LEM in tiger source sites using MIST, a computerized management information system for ranger-based data collection. The framework addresses many of the technical, practical and institutional challenges involved in the design, implementation, sustainability and evaluation of LEM. Adoption of such a framework for LEM is a cost-effective strategy to improve the efficiency of law enforcement efforts, to increase the motivation of enforcement staff and to promote the accountability of law enforcement agencies in addressing threats to tigers. When combined with independent, systematic and science-based monitoring of tigers and their prey, LEM has great potential for evaluating the effectiveness of protection-based conservation investments. 相似文献
50.
Elaine C Fitches Howard A Bell Michelle E Powell Emma Back Chiara Sargiotti Robert J Weaver John A Gatehouse 《Pest management science》2010,66(1):74-83
BACKGROUND: The toxicity of a fusion protein, ButalT/GNA, comprising a venom toxin (ButaIT) derived from the red scorpion, Mesobuthus tamulus (F.), and Galanthus nivalis agglutinin (GNA), was evaluated under laboratory conditions against several pest insects. Insecticidal activity was compared with SFI1/GNA, a fusion comprising a venom toxin (SFI1) derived from the European spider Segestria florentina (Rossi) and GNA, which has been previously demonstrated to be effective against lepidopteran and hemipteran pests, and to GNA itself. RESULTS: Injection assays demonstrated that both fusion proteins were toxic to lepidopteran larvae, dipteran adults, coleopteran adults and larvae and dictyopteran nymphs. ButalT/GNA was more toxic than SFI1/GNA in all cases. GNA itself made a minor contribution to toxicity. Oral toxicity of ButalT/GNA towards lepidopteran pests was confirmed against neonate Spodoptera littoralis (Boisd.), where incorporation at 2% dietary protein resulted in 50% mortality and > 85% reduction in growth compared with controls. ButaIT/GNA was orally toxic to Musca domestica L. adults, causing 75% mortality at 1 mg mL?1 in aqueous diets and, at 2 mg g?1 it was orally toxic to Tribolium castaneum (Herbst.), causing 60% mortality and a 90% reduction in growth. CONCLUSIONS: Toxicity of the ButaIT/GNA recombinant fusion protein towards a range of insect pests from different orders was demonstrated by injection bioassays. Feeding bioassays demonstrated the potential use of the ButaIT/GNA fusion protein as an orally active insecticide against lepidopteran, dipteran and coleopteran pests. These experiments provide further evidence that the development of fusion protein technology for the generation of new, biorational, anti‐insect molecules holds significant promise. © Crown Copyright 2009. Reproduced with permission of Her Majesty's Stationery Office. Published by John Wiley & Sons, Ltd. 相似文献