The anatomy and systematic position of the antpipits Conopophaga and Corythopis

The anatomical characters of the passerine family Conopophagidae have been reexamined. The sternum, syrinx, tarsus, antorbital osteology and pterylosis of Conopophaga and Corythopis were compared with a broad sample of other suboscines, with particular attention to the Formicariidae and Rhinocryptidae. Conopophaga was found to lie well within the range of variation of the Formicariidae in the principal characters (sternum and syrinx) used by Forbes in describing the Conopophagidae. The key character was the apparent presence in Conopophaga of a four-notched sternum. In nearly all specimens of Conopophaga, however, we found the sternum to have two notches and two large medial fenestrae. The four-notched condition is found in some species of Grallaria and Pittasoma, both considered to be formicariid. In most of the other characters studied also, Conopophaga strongly resembles Grallaria. The genus Corythopis differs from Conopophaga and all other furnarioids in the major diagnostic characters examined. In several respects, particularly the pterylosis and syringeal structure, it shows strong affinities with the Tyrannidae. It is recommended that Conopophaga be returned to its former position, near Grallaria in the Formicariidae. Corythopis must be moved from the Furnarioidea to the Tyrannoidea; its proper position appears to be in the family Tyrannidae

The "Odd" Behavior of Ozone Photodissociation

The dissociation dynamics of ozone photolysis in the Hartley band have been studied to help uncover the origin of the rotational population alternation. Velocity map ion imaging experiments have been performed on the dissociation of ozone at 248, 266 and 282 nm. Rotational distributions and vector correlations for the O2 (a ^1Δg) fragment have been measured to elucidate the origin of the observed even/odd J state population alternation. The population alternation is considerably stronger for jet-cooled ozone than the previous measurements at 300 K. The alternation is dependent on J state, i.e., it is weaker at the high and low sides of the rotational distribution, but the alternation is not greatly dependent on photolysis wavelength or O2 vibrational state. A simple curve crossing model has been used to explain the alternation. The difference in temperature between the previous and current experiments has led to the study of the parent internal energy effects on the alternation. The even/odd alternation is clearly present for a 60 ±10 K beam, but is not observed when the beam temperature reaches 200 ±20 K. This is direct evidence that the parent internal energy must be taken into account to explain the origin of the alternation and is inconsistent with a simple curve crossing model. The dissociation dynamics have also been studied to help determine if the odd and even J states arise from different dissociation pathways. The correlation between fragment velocity and rotational angular momentum, the v-J correlation, has been obtained, and no difference in the v-J correlation is observed between the even and odd J states. A previous research group has reported differences between the even and odd states for a 140 K beam, and the difference was shown to be dependent on fragment speed. Since no alternation is present for the 60 K beam, this indicates that the alternation of the v-J correlation may also be dependent on parent internal energy. The spatial anisotropy, the μ-v correlation, showed no alternation in both the current and previous results. It has been shown that the odd J state population increases with increasing parent internal energy, so the odd states may preferentially arise from parent molecules with out-of-plane rotational motion. When the internal energy of ozone is increased, the out-of-plane motion becomes more significant and produces more odd states. A consequence of this is that the out-of-plane motion will depolarize the v-J correlation more than the in-plane parent rotation, but it will not affect the μ-v correlation. Therefore, it would be expected that if the odd states are associated with rotationally excited parent molecules, the v-J would be more depolarized compared to the even states, but the spatial anisotropy would be the same for both states

Nascent O\u3csub\u3e2\u3c/sub\u3e (a\u3csup\u3e1\u3c/sup\u3eΔ\u3csub\u3eg\u3c/sub\u3e, v = 0, 1) Rotational Distributions from the Photodissociation of Jet‐Cooled O\u3csub\u3e3\u3c/sub\u3e in the Hartley Band

We report rotational distributions for the O2 (a 1Δg) fragment from photodissociation of jet‐cooled O3 at 248, 266, and 282 nm. The rotational distributions show a population alternation that favors the even states, as previously reported for a 300 K sample by Valentini et al. (J. Chem. Phys. 86, 6745 (1987)). The alternation from the jet‐cooled precursor is much stronger than that observed by Valentini et al., and in contrast to their observations does not depend strongly on O2 (a 1Δg) vibrational state or photolysis wavelength. The odd/even alternation diminishes substantially when the ozone beam temperature is increased from 60 to 200 K, confirming its dependence on parent internal energy. The magnitude of the even/odd alternation in product rotational states from the cold ozone sample, its temperature dependence, and other experimental and theoretical evidence reported since 1987 suggest that the alternation originates from a Λ‐doublet propensity, and not from a mass independent curve crossing effect as previously proposed

Chikungunya Virus Neutralization Antigens and Direct Cell-to-Cell Transmission Are Revealed by Human Antibody-Escape Mutants

Chikungunya virus (CHIKV) is an alphavirus responsible for numerous epidemics throughout Africa and Asia, causing infectious arthritis and reportedly linked with fatal infections in newborns and elderly. Previous studies in animal models indicate that humoral immunity can protect against CHIKV infection, but despite the potential efficacy of B-cell-driven intervention strategies, there are no virus-specific vaccines or therapies currently available. In addition, CHIKV has been reported to elicit long-lasting virus-specific IgM in humans, and to establish long-term persistence in non-human primates, suggesting that the virus might evade immune defenses to establish chronic infections in man. However, the mechanisms of immune evasion potentially employed by CHIKV remain uncharacterized. We previously described two human monoclonal antibodies that potently neutralize CHIKV infection. In the current report, we have characterized CHIKV mutants that escape antibody-dependent neutralization to identify the CHIKV E2 domain B and fusion loop “groove” as the primary determinants of CHIKV interaction with these antibodies. Furthermore, for the first time, we have also demonstrated direct CHIKV cell-to-cell transmission, as a mechanism that involves the E2 domain A and that is associated with viral resistance to antibody-dependent neutralization. Identification of CHIKV sub-domains that are associated with human protective immunity, will pave the way for the development of CHIKV-specific sub-domain vaccination strategies. Moreover, the clear demonstration of CHIKV cell-to-cell transmission and its possible role in the establishment of CHIKV persistence, will also inform the development of future anti-viral interventions. These data shed new light on CHIKV-host interactions that will help to combat human CHIKV infection and inform future studies of CHIKV pathogenesis

Development of a highly protective combination monoclonal antibody therapy against Chikungunya virus

Chikungunya virus (CHIKV) is a mosquito-transmitted alphavirus that causes global epidemics of a debilitating polyarthritis in humans. As there is a pressing need for the development of therapeutic agents, we screened 230 new mouse anti-CHIKV monoclonal antibodies (MAbs) for their ability to inhibit infection of all three CHIKV genotypes. Four of 36 neutralizing MAbs (CHK-102, CHK-152, CHK-166, and CHK-263) provided complete protection against lethality as prophylaxis in highly susceptible immunocompromised mice lacking the type I IFN receptor (Ifnar−/−) and mapped to distinct epitopes on the E1 and E2 structural proteins. CHK-152, the most protective MAb, was humanized, shown to block viral fusion, and require Fc effector function for optimal activity in vivo. In post-exposure therapeutic trials, administration of a single dose of a combination of two neutralizing MAbs (CHK-102+CHK-152 or CHK-166+CHK-152) limited the development of resistance and protected immunocompromised mice against disease when given 24 to 36 hours before CHIKV-induced death. Selected pairs of highly neutralizing MAbs may be a promising treatment option for CHIKV in humans

Comparing chromosomal and mitochondrial phylogenies of the Indriidae (Primates, Lemuriformes)

The Malagasy primate family Indriidae comprises three genera with up to 19 species. Cytogenetic and molecular phylogenies of the Indriidae have been performed with special attention to the genus Propithecus. Comparative R-banding and FISH with human paints were applied to karyotypes of representatives of all three genera and confirmed most of the earlier R-banding results. However, additional chromosomal rearrangements were detected. A reticulated and a cladistic phylogeny, the latter including hemiplasies, have been performed. Cladistic analysis of cytogenetic data resulted in a phylogenetic tree revealing (1) monophyly of the family Indriidae, (2) monophyly of the genus Avahi, (3) sister–group relationships between Propithecus diadema and Propithecus edwardsi, and (4) the grouping of the latter with Indri indri, Propithecus verreauxi, and Propithecus tattersalli, and thus suggesting paraphyly of the genus Propithecus. A molecular phylogeny based on complete mitochondrial cytochrome b sequences of 16 species indicated some identical relationships, such as the monophyly of Avahi and the sister–group relationships of the eastern (P. diadema and P. edwardsi) to the western Propithecus species (P. verreauxi, Propithecus coquereli, and P. tattersalli). However, the main difference between the molecular and cytogenetic phylogenies consists in an early divergence of Indri in the molecular phylogeny while in the chromosomal phylogeny it is nested within Propithecus. The similarities and differences between molecular and cytogenetic phylogenies in relation to data on the species’ geographic distributions and mating systems allow us to propose a scenario of the evolution of Indriidae. Chromosomal and molecular processes alone or in combination created a reproductive barrier that was then followed by further speciation processes

Red Sea palaeoclimate: stable isotope and element-ratio analysis of marine mollusc shells

The southern Red Sea coast is the location of more than 4,200 archaeological shell midden sites. These shell middens preserve archaeological and climatic archives of unprecedented resolution and scale. By using shells from these contexts, it is possible to link past environmental information with episodes of human occupation and resource processing. This chapter summarises current knowledge about the marine gastropod Conomurex fasciatus (Born 1778) and discusses its use in environmental and climatic reconstruction using stable isotope and elemental ratio analysis. It offers a review of the most recent studies of shell midden sites on the Farasan Islands, their regional importance during the mid-Holocene, theories about seasonal use of the coastal landscape, and preliminary results from new methods to acquire large climatic datasets from C. fasciatus shells

Recombinant Modified Vaccinia Virus Ankara Expressing Glycoprotein E2 of Chikungunya Virus Protects AG129 Mice against Lethal Challenge

Chikungunya virus (CHIKV) infection is characterized by rash, acute high fever, chills, headache, nausea, photophobia, vomiting, and severe polyarthralgia. There is evidence that arthralgia can persist for years and result in long-term discomfort. Neurologic disease with fatal outcome has been documented, although at low incidences. The CHIKV RNA genome encodes five structural proteins (C, E1, E2, E3 and 6K). The E1 spike protein drives the fusion process within the cytoplasm, while the E2 protein is believed to interact with cellular receptors and therefore most probably constitutes the target of neutralizing antibodies. We have constructed recombinant Modified Vaccinia Ankara (MVA) expressing E3E2, 6KE1, or the entire CHIKV envelope polyprotein cassette E3E26KE1. MVA is an appropriate platform because of its demonstrated clinical safety and its suitability for expression of various heterologous proteins. After completing the immunization scheme, animals were challenged with CHIV-S27. Immunization of AG129 mice with MVAs expressing E2 or E3E26KE1 elicited neutralizing antibodies in all animals and provided 100% protection against lethal disease. In contrast, 75% of the animals immunized with 6KE1 were protected against lethal infection. In conclusion, MVA expressing the glycoprotein E2 of CHIKV represents as an immunogenic and effective candidate vaccine against CHIKV infections