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Coral Reefs - This erratum has been initiated as many corrections which were submitted during proofing were overlooked by vendor.  相似文献   
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Lotus tenuis is a perennial legume with a good adaptation to infertile, heavy and waterlogging soils. It can replace alfalfa in these sites with a similar feeding value. An important constraint is its weak competitive capacity with other graminae and weed species in permanent pastures, having consequently a poor forage yield. The objective of the present research is to overcome this disadvantage, enhancing its competitive ability with foliar applications of GA3 (GA) and phosphorus (P), increasing L. tenuis forage yield. Field experiments were conducted during 1994 with foliar application of GA (50 mg.l-1) and during 1995 with foliar application of GA (25 and 50 mg.l-1), phosphorus (8 kg.ha-1, as P2O5) and their combinations, in permanent pastures with L. tenuis and other companion grasses. In 1994 GA 50 increased significantly L. tenuis dry matter (DML) in 64.6% but not the dry matter of graminae fraction (DMG) and in consequence the total dry matter of the pasture (TDMP) was increased. In 1995 all GA treatments and their combinations with phosphorus enhanced DML but not DMG. In this sense GA 25 + P was the most effective treatment with a 151% increment of DML. Consequently TDMP was significantly increased due to a larger participation of L. tenuis in the forage yield. This increase was achieved due to a greater length and diameter of L. tenuis branches, with a logical modification in leaf:stem ratio. Moreover GA treatments reduced L. tenuis flower number. Phosphorus treatment, applied alone, showed an increase in the DML. GA treatments did not modify the feeding value of the forage in L. tenuis and graminae fractions, except GA 50 and GA 50 + P in acid detergent fiber (ADF), neutral detergent fiber (NDF) and crude protein (CP), respect to the control. The total crude protein (CP.m-2) was enhanced in all GA and GA + P treatments. Foliar GA3 and phosphorus spray applications increased the competitiveness of trefoil for light, on account of morphological changes in the spatial disposition of L. tenuis stems reaching faster the top of the pasture canopy. This practice can be an adequate alternative to increase the forage yield and total crude protein in permanent and cultivated pastures with a low cost-benefit ratio.  相似文献   
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Coral Reefs - In French Polynesia, both currently recognized manta ray species, Mobula alfredi and M. birostris, are observed. Despite being an important cultural asset and generating significant...  相似文献   
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BACKGROUND: Pigmented lesions of the eye represent a challenging field from both clinical and pathologic approaches. The importance of a correct diagnosis in this case is enhanced by the delicate structures involved and their difficult accessibility. CASE: We report a case of a 51-year-old man with acute vision loss and the feeling of a foreign body in the left eye diagnosed with vitreous hemorrhage. A small, pigmented lesion in the proximity of optic nerve head was detected. After a 9-year follow-up, a definitive diagnosis of melanocytoma was achieved in vitrectomy cytology. Smears showed a population of plump, cohesive melanocytes and elongated cells with cytoplasmic melanin and uniform rounded nuclei. No change in the lesion has occurred 3 years after vitrectomy. CONCLUSION: Fine needle aspiration proved to be helpful and reliable for the correct diagnosis of melanocytoma, which does not require additional treatment.  相似文献   
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Human pressures have put many top predator populations at risk of extinction. Recent years have seen alarming declines in sharks worldwide, while their resilience remains poorly understood. Studying the ecology of small populations of marine predators is a priority to better understand their ability to withstand anthropogenic and environmental stressors. In the present study, we monitored a naturally small island population of 40 adult sicklefin lemon sharks in Moorea, French Polynesia over 5 years. We reconstructed the genetic relationships among individuals and determined the population’s mating system. The genetic network illustrates that all individuals, except one, are interconnected at least through one first order genetic relationship. While this species developed a clear inbreeding avoidance strategy involving dispersal and migration, the small population size, low number of breeders, and the fragmented environment characterizing these tropical islands, limits its complete effectiveness.  相似文献   
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In a recent paper [Ariño et al., Plant Mol Biol 21: 475–485 (1993)] we reported the amplification of a DNA fragment (AP-2) from the genome of Arabidopsis thaliana encoding an amino acid sequence corresponding to a Ser/Thr protein phosphatase distantly related to type 2A protein phosphatases. In this paper we report the use of the AP-2 fragment to isolate several cDNA clones from a leaf cDNA library. Two of these (EP 124 and Ep 129) largely overlap and contain the AP-2 sequence, whereas a third clone (EP 128) is different although very related in sequence (86% of identity). Clones EP 124/EP 129 and EP 128 were found to encode two highly related polypeptides (93% identity) of 305 residues, showing a very high identity (83%) to the catalytic subunit of protein phosphatase X (PPX) from rabbit. Therefore, they have been named PPX-1 (EP 124/EP 129) and PPX-2 (EP 128). Southern blot analysis of genomic DNA indicates that only these two genes encoding phosphatases closely related to PPX are present in the genome of A. thaliana. Both PPX-1 and PPX-2 are expressed at very low levels in A. thaliana flowers, leaves, stems and roots. The expression levels of four previously identified type 2A phosphatases are higher than those of PPX genes. PP2A-1 appears to be the major mRNA species detected in all the tissues analyzed.  相似文献   
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Knowledge of the habitat use and migration patterns of large sharks is important for assessing the effectiveness of large predator Marine Protected Areas (MPAs), vulnerability to fisheries and environmental influences, and management of shark–human interactions. Here we compare movement, reef-fidelity, and ocean migration for tiger sharks, Galeocerdo cuvier, across the Coral Sea, with an emphasis on New Caledonia. Thirty-three tiger sharks (1.54 to 3.9 m total length) were tagged with passive acoustic transmitters and their localised movements monitored on receiver arrays in New Caledonia, the Chesterfield and Lord Howe Islands in the Coral Sea, and the east coast of Queensland, Australia. Satellite tags were also used to determine habitat use and movements among habitats across the Coral Sea. Sub-adults and one male adult tiger shark displayed year-round residency in the Chesterfields with two females tagged in the Chesterfields and detected on the Great Barrier Reef, Australia, after 591 and 842 days respectively. In coastal barrier reefs, tiger sharks were transient at acoustic arrays and each individual demonstrated a unique pattern of occurrence. From 2009 to 2013, fourteen sharks with satellite and acoustic tags undertook wide-ranging movements up to 1114 km across the Coral Sea with eight detected back on acoustic arrays up to 405 days after being tagged. Tiger sharks dove 1136 m and utilised three-dimensional activity spaces averaged at 2360 km3. The Chesterfield Islands appear to be important habitat for sub-adults and adult male tiger sharks. Management strategies need to consider the wide-ranging movements of large (sub-adult and adult) male and female tiger sharks at the individual level, whereas fidelity to specific coastal reefs may be consistent across groups of individuals. Coastal barrier reef MPAs, however, only afford brief protection for large tiger sharks, therefore determining the importance of other oceanic Coral Sea reefs should be a priority for future research.  相似文献   
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