The Tropical managed Forests Observatory: a research network addressing the future of tropical logged forests

While attention on logging in the tropics has been increasing, studies on the long-term effects of silviculture on forest dynamics and ecology remain scare and spatially limited. Indeed, most of our knowledge on tropical forests arises from studies carried out in undisturbed tropical forests. This bias is problematic given that logged and disturbed tropical forests are now covering a larger area than the so-called primary forests. A new network of permanent sample plots in logged forests, the Tropical managed Forests Observatory (TmFO), aims to fill this gap by providing unprecedented opportunities to examine long-term data on the resilience of logged tropical forests at regional and global scales. TmFO currently includes 24 experimental sites distributed across three tropical regions, with a total of 490 permanent plots and 921 ha of forest inventories.     

Les algues calcaires du crétacé supérieur des rides de Villagrains,Landiras et Roquefort,Creon (Aquitaine centrale)

The lower Senonian of Central Aquitaine includes few calcareous algae, alone green algae, while the upper Senonian admits nothing but numerous red algae.A new species has been discovered (Lithothamnium villaegranis n. sp.). Solenomeris, generally frequent in the Paleocene deposits, has been identified in the maestrichtian levels.     

Polyclony and low relative heterozygosity in a widespread unisexual vertebrate,Lepidodactylus lugubris (Sauria)

Contrary to other unisexual vertebrates except a little-known fossorial snake, the Indo-Pacific anthropophilous, parthenogenetic lacertilian Lipododactylus lugubris is vastly more widespread than its bisexual relatives. At the same time, it shows negligible enzyme polymorphism and low overall heterozygosity in its usual diploid condition, which suggests the possibility that hybridization did not intervene when thelytoky was brought about. Clones are in much higher proportion among the sympatric triploids, but they too have a low relative heterozygosity, compounded by gene dosage restriction since no more than two out of the three alleles have been found expressed at any locus. Isozyme data suggest an origin of the complex in South East Asia, which conclusion is substantiated by the presence of a bisexual sibling species in the Philippine Islands.     

Comparative immunochemical study of the serum proteins of Lacertilia (Reptilia)]

The immunochemical relationships of the serum proteins of Uromastix acanthinurus, Agama mutabilis, Oplurus cuvieri, O. quadrimaculatus, Chamaeleo chamaeleon, Chalcides ocellatus and Lacerta lepida were studied by means of immunoelectrophoresis with an antiserum anti-Uromastix successively absorbed. Homogeneity of the Iguania species was pointed out and they were found more closely related to the Scincid Chalcides ocellatus than to the Lacertid Lacerta lepida. Within the Iguania, the two Agamids are immunologically more closely related to the Chamaeleon than to the two Iguanids.     

Résorption intestinale de la ferritine chez deux espèces animales aux possibilités d'absorption protéique néonatale différentes

Summary The intestinal absorption of equine ferritin was studied in newborn rats and rabbits by means of electron microscopy and immunological tests.The absorption of ferritin begins by invagination of the plasma membrane, which forms vesicles and vacuoles in the brush border region. The ferritin moves downwards into the great supranuclear vacuole and then is taken up by the Golgi complex. The protein travels freely through the neighbouring cytoplasm and arrives into the dilated intercellular space. After passing through the basal membrane, the ferritin penetrates into the vessels.The intracellular course of ferritin is the same in both species and corresponds to that of other substances such as lipids.On the contrary, the immunological demonstration of this protein in peripheral blood is possible only in newborn rats; in young rabbits it disappears immediately after its arrival in the circulation.

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Nous exprimons notre reconnaissance au Chef du Centre de Microscopie Electronique, Monsieur A. Gautier, pour ses conseils et ses suggestions, et à Monsieur D. Anders pour sa collaboration technique. Les schémas ont été réalisés par Monsieur O. Jenni et nous l'en remercions vivement.Pour ce travail nons avons bénéficié d'une aide financière de la Maison Nestlé S. A. Vevey, à laquelle nous témoignons notre gratitude.     

Intranasal vaccination with a lentiviral vector protects against SARS-CoV-2 in preclinical animal models

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Comparative study of sexual cycles, oogenesis and spawning of two Soleidae, Solea lascaris (Risso, 1810) and Solea impar (Bennet, 1831), on the western coast of Brittany

Two sand sole species, Solea lascaris and Solea impar , are common on the western coast of Brittany, France. Their reproduction (oogenesis and spawning) has been studied by following the gonadosomatic index, histological changes in ovary development, and oocyte diameter distribution. Both species have a prolonged spawning season, from spring to late summer. Each mature female breeds twice during the spawning season: in May and July for 5. lascaris , and in early June and July for 5. impar. Throughout the spawning season, several oocyte batches undergo vitellogenesis and there is a continuous recruitment of immature or primary oocytes into vitellogenesis. The two species are thus serial synchronous spawners. This, together with oocyte atresia late in the season (especially noticeable in S. impar ) makes fecundity estimation difficult.