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| Author | Leroy, C.; Jauneau, A.; Quilichini, A.; Dejean, A.; Orivel, J. | ||||
| Title | Comparative Structure and Ontogeny of the Foliar Domatia in Three Neotropical Myrmecophytes | Type | Journal Article | ||
| Year | 2010 | Publication | American Journal of Botany | Abbreviated Journal | Am. J. Bot. |
| Volume | 97 | Issue | 4 | Pages  |
557-565 |
| Keywords | anatomy; ant-plant mutualism; Chrysobalanaceae; domatia; French Guiana; Hirtella physophora; Maieta guianensis; Melastomataceae; myrmecophyte; ontogeny; Tococa guianensis | ||||
| Abstract | The origin and timing of the appearance of leaf domatia during the ontogeny of plants are important evolutionary traits driving the maintenance of ant-plant associations. In this study conducted in French Guiana on Hirtella physophora, Maieta guianensis, and Tococa guianensis, we focused on the formation and development of leaf domatia having different morphological origins. We modeled the timing of the onset of these domatia, then compared their morpho-anatomical structure. Although the ontogenetic development of the domatia differed between species, they developed very early in the plant's ontogeny so that we did not note differences in the timing of the onset of these domatia. For H. physophora seedlings, a transitional leaf forms before the appearance of fully developed domatia, whereas in M. guianensis and T. guianensis the domatia forms abruptly without transitional leaves. Moreover, in all cases, the morpho-anatomical structure of the domatia differed considerably from the lamina. All three species had similar morpho-anatomical characteristics for the domatia, indicating a convergence in their structural and functional characteristics. This convergence between taxonomically distant plant species bearing domatia having different morphological origins could be interpreted as a product of the plant's evolution toward the morphology and anatomy most likely to maximize ant recruitment and long-term residence. | ||||
| Address | [Leroy, Celine; Dejean, Alain] CNRS, Unite Mixte Rech Ecol Forets Guyane, F-97379 Kourou, France, Email: Celine.Leroy@ecofog.gf | ||||
| Corporate Author | Thesis | ||||
| Publisher | BOTANICAL SOC AMER INC | Place of Publication | Editor | ||
| Language | Summary Language | Original Title | |||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0002-9122 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | ISI:000276045500003 | Approved | no | ||
| Call Number | EcoFoG @ eric.marcon @ | Serial | 65 | ||
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| Author | Hamadi, A.; Borderies, P.; Albinet, C.; Koleck, T.; Villard, L.; Ho Tong Minh, D.; Le Toan, T.; Burban, B. | ||||
| Title | Temporal coherence of tropical forests at P-band: Dry and rainy seasons | Type | Journal Article | ||
| Year | 2015 | Publication | IEEE Geoscience and Remote Sensing Letters | Abbreviated Journal | IEEE Geosci. Remote Sens. Lett. |
| Volume | 12 | Issue | 3 | Pages |
557-561 |
| Keywords | Biomass mission; forest scattering; ground-based experiment; P-band; range impulse response; temporal coherence | ||||
| Abstract | In this letter, the temporal coherence of tropical forest scattering at P-band is addressed by means of a ground-based experiment. The study is based on the TropiScat campaign in French Guiana, designed to support the Biomass mission, which will be the ESA 7th Earth Explorer mission. For Biomass, temporal coherence is a crucial parameter for coherent processing of polarimetric synthetic aperture radar (SAR) interferometry and SAR tomography in repeat-pass acquisitions. During the experiment, data were continuously collected for six months during both the rainy and dry seasons. For the rain-free days in both seasons, the coherence exhibits a daily cycle showing a high decorrelation during daytime, which is likely due to motion in the canopy. Up to a 20-day baseline, the coherence is much higher in the dry season than in the rainy season (> 0.8). From 20 to 40 days, it presents the same order of magnitude in both seasons [0.6, 0.7]. For larger temporal baselines, it becomes lower in the dry season. The results can be used to assess the long-term coherence of repeat-pass observations over a tropical forest. However, an extension of this study to several years and over other forest spots would be necessary to draw more general conclusions. | ||||
| Address | EcoFogKourou, France | ||||
| Corporate Author | Thesis | ||||
| Publisher | Institute of Electrical and Electronics Engineers Inc. | Place of Publication | Editor | ||
| Language | Summary Language | Original Title | |||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1545598x (Issn) | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Export Date: 21 October 2014; Correspondence Address: Hamadi, A.; Centre d'Etudes Spatiales de la BiosphèreFrance; Funding Details: ESA, European Space Agency | Approved | no | ||
| Call Number | EcoFoG @ webmaster @ | Serial | 563 | ||
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| Author | Bandou, E.; Lebailly, F.; Muller, F.; Dulormne, M.; Toribio, A.; Chabrol, J.; Courtecuisse, R.; Plenchette, C.; Prin, Y.; Duponnois, R.; Thiao, M.; Sylla, S.; Dreyfus, B.; Ba, A.M. | ||||
| Title | The ectomycorrhizal fungus Scleroderma bermudense alleviates salt stress in seagrape (Coccoloba uvifera L.) seedlings | Type | Journal Article | ||
| Year | 2006 | Publication | Mycorrhiza | Abbreviated Journal | Mycorrhiza |
| Volume | 16 | Issue | 8 | Pages |
559-565 |
| Keywords | Coccoloba uvifera; ectomycorrhizal dependency; mineral uptake; salt stress; water status | ||||
| Abstract | The purpose of this study was to test the capacity of the ectomycorrhizal (ECM) fungus, Scleroderma bermudense, to alleviate saline stress in seagrape (Coccoloba uvifera L.) seedlings. Plants were grown over a range (0, 200, 350 and 500 mM) of NaCl levels for 12 weeks, after 4 weeks of non-saline pre-treatment under greenhouse conditions. Growth and mineral nutrition of the seagrape seedlings were stimulated by S. bermudense regardless of salt stress. Although ECM colonization was reduced with increasing NaCl levels, ECM dependency of seagrape seedlings increased. Tissues of ECM plants had significantly increased concentrations of P and K but lower Na and Cl concentrations than those of non-ECM plants. Higher K concentrations in the leaves of ECM plants suggested a higher osmoregulating capacity of these plants. Moreover, the water status of ECM plants was improved despite their higher evaporative leaf surface. The results suggest that the reduction in Na and Cl uptake together with a concomitant increase in P and K absorption and a higher water status in ECM plants may be important salt-alleviating mechanisms for seagrape seedlings growing in saline soils. | ||||
| Address | Univ Antilles Guyane, Fac Sci Exactes & Nat, Lab Biol & Physiol Vegetales, F-97159 Guadeloupe, France, Email: amadou.ba@univ-ag.fr | ||||
| Corporate Author | Thesis | ||||
| Publisher | SPRINGER | Place of Publication | Editor | ||
| Language | Summary Language | Original Title | |||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0940-6360 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | ISI:000241687200006 | Approved | no | ||
| Call Number | EcoFoG @ eric.marcon @ | Serial | 221 | ||
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| Author | Hardy, O.J.; Maggia, L.; Bandou, E.; Breyne, P.; Caron, H.; Chevallier, M.H.; Doligez, A.; Dutech, C.; Kremer, A.; Latouche-Halle, C.; Troispoux, V.; Veron, V.; Degen, B. | ||||
| Title | Fine-scale genetic structure and gene dispersal inferences in 10 Neotropical tree species | Type | Journal Article | ||
| Year | 2006 | Publication | Molecular Ecology | Abbreviated Journal | Mol. Ecol. |
| Volume | 15 | Issue | 2 | Pages |
559-571 |
| Keywords | French Guiana; gene dispersal; seed dispersal; spatial genetic structure; tropical trees | ||||
| Abstract | The extent of gene dispersal is a fundamental factor of the population and evolutionary dynamics of tropical tree species, but directly monitoring seed and pollen movement is a difficult task. However, indirect estimates of historical gene dispersal can be obtained from the fine-scale spatial genetic structure of populations at drift-dispersal equilibrium. Using an approach that is based on the slope of the regression of pairwise kinship coefficients on spatial distance and estimates of the effective population density, we compare indirect gene dispersal estimates of sympatric populations of 10 tropical tree species. We re-analysed 26 data sets consisting of mapped allozyme, SSR (simple sequence repeat), RAPD (random amplified polymorphic DNA) or AFLP (amplified fragment length polymorphism) genotypes from two rainforest sites in French Guiana. Gene dispersal estimates were obtained for at least one marker in each species, although the estimation procedure failed under insufficient marker polymorphism, limited sample size, or inappropriate sampling area. Estimates generally suffered low precision and were affected by assumptions regarding the effective population density. Averaging estimates over data sets, the extent of gene dispersal ranged from 150 m to 1200 m according to species. Smaller gene dispersal estimates were obtained in species with heavy diaspores, which are presumably not well dispersed, and in populations with high local adult density. We suggest that limited seed dispersal could indirectly limit effective pollen dispersal by creating higher local tree densities, thereby increasing the positive correlation between pollen and seed dispersal distances. We discuss the potential and limitations of our indirect estimation procedure and suggest guidelines for future studies. | ||||
| Address | Univ Libre Bruxelles, Serv Ecoethol Evolut, B-1050 Brussels, Belgium, Email: ohardy@ulb.ac.be | ||||
| Corporate Author | Thesis | ||||
| Publisher | BLACKWELL PUBLISHING | Place of Publication | Editor | ||
| Language | Summary Language | Original Title | |||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0962-1083 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | ISI:000235045500021 | Approved | no | ||
| Call Number | EcoFoG @ eric.marcon @ | Serial | 183 | ||
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| Author | Dejean, A.; Compin, A.; Delabie, J.H.C.; Azémar, F.; Corbara, B.; Leponce, M. | ||||
| Title | Biotic and abiotic determinants of the formation of ant mosaics in primary Neotropical rainforests | Type | Journal Article | ||
| Year | 2019 | Publication | Ecological Entomology | Abbreviated Journal | Ecol Entomol |
| Volume | 44 | Issue | 4 | Pages |
560-570 |
| Keywords | Ant mosaics; connections on the ground; host tree attractiveness; indicators of disturbance; primary Neotropical rainforest; territoriality | ||||
| Abstract | 1. Ants are widespread in tropical rainforests, including in the canopy where territorially dominant arboreal species represent the main part of the arthropod biomass.
2. By mapping the territories of dominant arboreal ant species and using a null model analysis and a pairwise approach this study was able to show the presence of an ant mosaic on the upper canopy of a primary Neotropical rainforest (c. 1ha sampled; 157 tall trees from 28 families). Although Neotropical rainforest canopies are frequently irregular, with tree crowns at different heights breaking the continuity of the territories of dominant ants, the latter are preserved via underground galleries or trails laid on the ground. 3. The distribution of the trees influences the structure of the ant mosaic, something related to the attractiveness of tree taxa for certain arboreal ant species rather than others. 4. Small-scale natural disturbances, most likely strong winds in the area studied (presence of canopy gaps), play a role by favouring the presence of two ant species typical of secondary formations: Camponotus femoratus and Crematogaster levior, which live in parabiosis (i.e. share territories and nests but lodge in different cavities) and build conspicuous ant gardens. In addition, pioneer Cecropia myrmecophytic trees were recorded. |
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| Publisher | John Wiley & Sons, Ltd (10.1111) | Place of Publication | Editor | ||
| Language | Summary Language | Original Title | |||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0307-6946 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | doi: 10.1111/een.12735 | Approved | no | ||
| Call Number | EcoFoG @ webmaster @ | Serial | 882 | ||
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| Author | Epron, D.; Bosc, A.; Bonal, D.; Freycon, V. | ||||
| Title | Spatial variation of soil respiration across a topographic gradient in a tropical rain forest in French Guiana | Type | Journal Article | ||
| Year | 2006 | Publication | Journal of Tropical Ecology | Abbreviated Journal | J. Trop. Ecol. |
| Volume | 22 | Issue | Pages |
565-574 | |
| Keywords | acrisol; carbon balance; carbon flux; gleysol; root biomass | ||||
| Abstract | The objective of this study was to analyse the factors explaining spatial variation in soil respiration over topographic transects in a tropical rain forest of French Guiana. The soil of 30 plots along six transects was characterized. The appearance of the 'dry to the touch' character at a depth of less than 1.2 m was used to discriminate soils exhibiting vertical drainage from soils exhibiting superficial lateral drainage and along with colour and texture, to define five classes from well-drained to strongly hydromorphic soils. Spatial variation in soil respiration was closely related to topographic position and soil type. Increasing soil water content and bulk density and decreasing root biomass and soil carbon content explained most of the decrease in soil respiration from the plateaux (vertically drained hypoferralic acrisol) to the bottomlands (haplic gleysol). These results will help to stratify further field experiments and to identify the underlying determinants of spatial variation in soil respiration to develop mechanistic models of soil respiration. | ||||
| Address | Univ Nancy 1, UMR 1137, INRA, UHP Ecol & Ecophysiol Forestieres,Fac Sci, F-54506 Vandoeuvre Les Nancy, France, Email: Daniel.Epron@scbiol.uhp-nancy.fr | ||||
| Corporate Author | Thesis | ||||
| Publisher | CAMBRIDGE UNIV PRESS | Place of Publication | Editor | ||
| Language | Summary Language | Original Title | |||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0266-4674 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | ISI:000239975200008 | Approved | no | ||
| Call Number | EcoFoG @ eric.marcon @ | Serial | 179 | ||
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| Author | Dezerald, O.; Céréghino, R.; Corbara, B.; Dejean, A.; Leroy, C. | ||||
| Title | Temperature: Diet Interactions Affect Survival through Foraging Behavior in a Bromeliad-Dwelling Predator | Type | Journal Article | ||
| Year | 2015 | Publication | Biotropica | Abbreviated Journal | Biotropica |
| Volume | 47 | Issue | 5 | Pages |
569-578 |
| Keywords | Toxorhynchites haemorrhoidalis; Biocontrol agent; Development; French Guiana; Selective feeding behavior; Tank bromeliad | ||||
| Abstract | Temperature, food quantity and quality play important roles in insect growth and survival, influencing population dynamics as well as interactions with other community members. However, the interaction between temperature and diet and its ecological consequences have been poorly documented. Toxorhynchites are well-known biocontrol agents for container-inhabiting mosquito larvae. We found that Toxorhynchites haemorrhoidalis larvae (Diptera: Culicidae) inhabiting water-filled rosettes of tank bromeliads catch and eat prey of both aquatic (mosquito larvae) and terrestrial origin (ants), using distinct predatory methods. They carried out frontal attacks on ants, but ambushed mosquito larvae. In choice tests, T. haemorrhoidalis favored terrestrial prey. Temperature had a significant effect on predator development and survival through its interaction with diet, but did not alter the preference for ants. T. haemorrhoidalis larvae emerged quickly when fed only mosquito larvae, whereas all individuals died before pupation when fed only ants. We conclude that behavioral factors (i.e., attraction to ants that disturb the surface of the water) overtake physiological factors (i.e., the adverse outcome of elevated temperature and an ant-based diet) in determining a predator's response to temperature:diet interactions. Finally, because T. haemorrhoidalis larvae preferentially feed on terrestrial insects in tank bromeliads, mosquito larvae may indirectly benefit from predation release. © 2015 Association for Tropical Biology and Conservation Inc. | ||||
| Address | UMR AMAP (botAnique et Modelisation de l'Architecture des Plantes et des vegetations), IRD, Boulevard de la Lironde, TA A-51/PS2, Montpellier Cedex 5, France | ||||
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| Notes | Export Date: 17 September 2015 | Approved | no | ||
| Call Number | EcoFoG @ webmaster @ | Serial | 624 | ||
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| Author | Gonzalès-Melo, Andrès ; Posada, Juan Manuel ; Beauchêne, Jacques ; Lehnebach, Romain ; Leviennois, Sébastien ; Rivera, Katherine ; Clair, Bruno | ||||
| Title | Radial variations in wood functional traits in a rain forest from eastern Amazonia | Type | Journal Article | ||
| Year | 2021 | Publication | Trees | Abbreviated Journal | |
| Volume | 36 | Issue | Pages |
569–581 | |
| Keywords | |||||
| Abstract | Trees can modify their wood structure in response to changes in mechanical, hydraulic and storage demands during their life-cycles. Thus, examining radial variations in wood traits is important to expand our knowledge of tree functioning and species ecological strategies. Yet, several aspects of radial changes in wood functional traits are still poorly understood, especially in angiosperm trees from tropical humid forests. Here, we examined radial shifts in wood traits in trunks of tropical forest species and explored their potential ecological implications. We first examined radial variations in wood specific gravity (WSG). Then, we asked what anatomical traits drove radial variations in WSG, and whether WSG, vessel fraction and specific hydraulic conductivity vary independently from each other along the radius gradients. We measured WSG and eight wood anatomical traits, at different radial positions along the trunks, in 19 tree species with contrasting shade-tolerance from a lowland tropical forest in eastern Amazonia. Most species had significant radials shifts in WSG. Positive radial gradients in WSG (i.e., increments from pith to bark) were common among shade-intolerant species and were explained by different combinations of fiber and parenchyma traits, while negative radial shifts in WSG (e.g., decreases towards the bark) were present in shade-tolerants, but were generally weakly related to anatomical traits. We also found that, in general, WSG was unrelated to vessel fraction and specific hydraulic conductivity in any radial position. This study illustrates the contrasting radial variations in wood functional traits that occur in tree species from a humid lowland tropical forest. In particular, our results provide valuable insights into the anatomical traits driving WSG variations during tree development. These insights are important to expand our knowledge on tree ecological strategies by providing evidence on how wood allocation varies as trees grow, which in turn can be useful in studying trait-demography associations, and in estimating tree above-ground biomass. | ||||
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| Publisher | Springer Link | Place of Publication | Editor | ||
| Language | Summary Language | Original Title | |||
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| Notes | Approved | no | |||
| Call Number | EcoFoG @ webmaster @ | Serial | 1037 | ||
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| Author | Masse, P.S.M.; Kenne, M.; Mony, R.; Dejean, A.; Tindo, M. | ||||
| Title | Initial behavior in colony fragments of an introduced population of the invasive ant Wasmannia auropunctata | Type | Journal Article | ||
| Year | 2011 | Publication | Comptes Rendus Biologies | Abbreviated Journal | C. R. Biol. |
| Volume | 334 | Issue | 7 | Pages |
572-576 |
| Keywords | Aggregation; Death feigning; Thanatosis; Worker transportation; Biological invasion; Little fire ant | ||||
| Abstract | We investigated in the laboratory the initial behavior of propagules of the invasive ant Wasmannia auropunctata in Cameroon where it has been introduced. Both workers and queens at first feigned death (thanatosis), and then the workers slowly moved around the experimental arena; the queens did the same about 10 seconds later. Each queen antennated selected workers that then aggregated together by grasping the hind leg of another ant with their mandibles. When encountering the queen again, the lead worker climbed up the queen's hind leg and onto her back, followed by some other individuals. The remaining workers followed the queen to a location in the experimental arena. When brood was present, the workers transferred it to this location. Orphaned workers did not aggregate, but gathered the brood together and took care of it. By permitting propagules to survive, these behaviors likely contribute to the success of W. auropunctata as an invader. (C) 2011 Academie des sciences. Published by Elsevier Masson SAS. All rights reserved. | ||||
| Address | [Kenne, M; Mony, R; Tindo, M] Univ Douala, Fac Sci, Dept Biol Organismes Anim, Douala, Cameroon, Email: tindodouala@yahoo.com | ||||
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| Publisher | Elsevier France-Editions Scientifiques Medicales Elsevier | Place of Publication | Editor | ||
| Language | Summary Language | Original Title | |||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1631-0691 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | WOS:000293673300010 | Approved | no | ||
| Call Number | EcoFoG @ webmaster @ | Serial | 332 | ||
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| Author | Dejean, A.; Corbara, B.; Azémar, F.; Carpenter, J.M. | ||||
| Title | When attempts at robbing prey turn fatal | Type | Journal Article | ||
| Year | 2012 | Publication | Naturwissenschaften | Abbreviated Journal | Naturwissenschaften |
| Volume | 99 | Issue | 7 | Pages |
579-582 |
| Keywords | Ant predation; Azteca andreae; Cleptobiosis; Flies and dung beetles; Myrmecophyte; Reduviidae; Socialwasps; Stinglessbees | ||||
| Abstract | Because group-hunting arboreal ants spread-eagle insect prey for a long time before retrieving them, these prey can be coveted by predatory flying insects. Yet, attempting to rob these prey is risky if the ant species is also an effective predator. Here, we show that trying to rob prey from Azteca andreae workers is a fatal error as 268 out of 276 potential cleptobionts (97.1 %) were captured in turn. The ant workers hunt in a group and use the “Velcro®” principle to cling firmly to the leaves of their host tree, permitting them to capture very large prey. Exceptions were one social wasp, plus some Trigona spp. workers and flies that landed directly on the prey and were able to take off immediately when attacked. We conclude that in this situation, previously captured prey attract potential cleptobionts that are captured in turn in most of the cases. © Springer-Verlag 2012. | ||||
| Address | Division of Invertebrate Zoology, American Museum of Natural History, Central Park West at 79th Street, New York, NY 10024, United States | ||||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 00281042 (Issn) | ISBN | Medium | ||
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| Notes | Export Date: 30 July 2012; Source: Scopus; Coden: Natwa; doi: 10.1007/s00114-012-0929-x; Language of Original Document: English; Correspondence Address: Dejean, A.; CNRS, Écologie des Forêts de Guyane (UMR-CNRS 8172), Campus agronomique, BP 316, 97379 Kourou cedex, France; email: alain.dejean@wanadoo.fr | Approved | no | ||
| Call Number | EcoFoG @ webmaster @ | Serial | 417 | ||
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