Iron oxidation at low temperature (260–500 C) in air and the effect of water vapor

The oxidation of iron has been studied at low temperatures (between 260 and 500 C) in dry air or air with 2 vol% H2O, in the framework of research on dry corrosion of nuclear waste containers during long-term interim storage. Pure iron is regarded as a model material for low-alloyed steel. Oxidation tests were performed in a thermobalance (up to 250 h) or in a laboratory furnace (up to 1000 h). The oxide scales formed were characterized using SEM-EDX, TEM, XRD, SIMS and EBSD techniques. The parabolic rate constants deduced from microbalance experiments were found to be in good agreement with the few existing values of the literature. The presence of water vapor in air was found to strongly influence the transitory stages of the kinetics. The entire structure of the oxide scale was composed of an internal duplex magnetite scale made of columnar grains and an external hematite scale made of equiaxed grains. 18O tracer experiments performed at 400 C allowed to propose a growth mechanism of the scale

Osteoarthritis-Like Changes in Bardet–Biedl Syndrome Mutant Ciliopathy Mice (Bbs1M390R/M390R): Evidence for a Role of Primary Cilia in Cartilage Homeostasis and Regulation of Inflammation

Osteoarthritis (OA) is a debilitating inflammation related disease characterized by joint pain and effusion, loss of mobility, and deformity that may result in functional joint failure and significant impact on quality of life. Once thought of as a simple “wear and tear” disease, it is now widely recognized that OA has a considerable metabolic component and is related to chronic inflammation. Defects associated with primary cilia have been shown to be cause OA-like changes in Bardet–Biedl mice. We examined the role of dysfunctional primary cilia in OA in mice through the regulation of the previously identified degradative and pro-inflammatory molecular pathways common to OA. We observed an increase in the presence of pro-inflammatory markers TGFβ-1 and HTRA1 as well as cartilage destructive protease MMP-13 but a decrease in DDR-2. We observed a morphological difference in cartilage thickness in Bbs1M390R/M390R mice compared to wild type (WT). We did not observe any difference in OARSI or Mankin scores between WT and Bbs1M390R/M390R mice. Primary cilia appear to be involved in the upregulation of biomarkers, including pro-inflammatory markers common to OA

Genetic variability and ontogeny predict microbiome structure in a disease-challenged montane amphibian

Amphibian populations worldwide are at risk of extinction from infectious diseases, including chytridiomycosis caused by the fungal pathogen Batrachochytrium dendrobatidis (Bd). Amphibian cutaneous microbiomes interact with Bd and can confer protective benefits to the host. The composition of the microbiome itself is influenced by many environment- and host-related factors. However, little is known about the interacting effects of host population structure, genetic variation and developmental stage on microbiome composition and Bd prevalence across multiple sites. Here we explore these questions in Amietia hymenopus, a disease-affected frog in southern Africa. We use microsatellite genotyping and 16S amplicon sequencing to show that the microbiome associated with tadpole mouthparts is structured spatially, and is influenced by host genotype and developmental stage. We observed strong genetic structure in host populations based on rivers and geographic distances, but this did not correspond to spatial patterns in microbiome composition. These results indicate that demographic and host genetic factors affect microbiome composition within sites, but different factors are responsible for host population structure and microbiome structure at the between-site level. Our results help to elucidate complex within- and among- population drivers of microbiome structure in amphibian populations. That there is a genetic basis to microbiome composition in amphibians could help to inform amphibian conservation efforts against infectious diseases

Does public awareness increase support for invasive species management?:Promising evidence across taxa and landscape types

Management of invasive species often raises substantial conflicts of interest. Since such conflicts can hamper proposed management actions, managers, decision makers and researchers increasingly recognize the need to consider the social dimensions of invasive species management. In this exploratory study, we aimed (1) to explore whether species’ taxonomic position (i.e. animals vs. plants) and type of invaded landscape (i.e. urban vs. nonurban) might influence public perception about the management of invasive species, and (2) to assess the potential of public awareness to increase public support for invasive species management. We reviewed the scientific literature on the conflicts of interest around the management of alien species and administered two-phased questionnaires (before and after providing information on the target species and its management) to members of the public in South Africa and the UK (n = 240). Our review suggests that lack of public support for the management of invasive animals in both urban and non-urban areas derives mainly from moralistic value disagreements, while the management of invasive plants in non-urban areas mostly causes conflicts based on utilitarian value disagreements. Despite these general trends, conflicts are context dependent and can originate from a wide variety of different views. Notably, informing the public about the invasive status and negative impacts of the species targeted for management appeared to increase public support for the management actions. Therefore, our results align with the view that increased public awareness might increase the public support for the management of invasive species, independent of taxonomic position and type of landscape

Com o diabo no corpo: os terríveis papagaios do Brasil colônia

Desde a Antiguidade, papagaios, periquitos e afins (Psittacidae) fascinaram os europeus por seu vivo colorido e uma notável capacidade de interação com seres humanos. A descoberta do Novo Mundo nada faria além de acrescentar novos elementos ao tráfico de animais exóticos há muito estabelecido pelos europeus com a África e o Oriente. Sem possuir grandes mamíferos, a América tropical participaria desse comércio com o que tinha de mais atrativo, essencialmente felinos, primatas e aves - em particular os papagaios, os quais eram embarcados em bom número. Contudo, a julgar pelos documentos do Brasil colônia, esses voláteis podiam inspirar muito pouca simpatia, pois nenhum outro animal - exceto as formigas - foi tantas vezes mencionado como praga para a agricultura. Além disso, alguns psitácidas mostravam-se tão loquazes que inspiravam a séria desconfiança de serem animais demoníacos ou possessos, pois só três classes de entidades - anjos, homens e demônios - possuíam o dom da palavra. Nos dias de hoje, vários representantes dos Psittacidae ainda constituem uma ameaça para a agricultura, enquanto os indivíduos muito faladores continuam despertando a suspeita de estarem possuídos pelo demônio. Transcendendo a mera curiosidade, essa crença exemplifica o quão intrincadas podem ser as relações do homem com o chamado “mundo natural”, revelando um universo mais amplo e multifacetado do que se poderia supor a princípio. Nesse sentido, a existência de aves capazes de falar torna essa relação ainda mais complexa e evidencia que as dificuldades de estabelecer o limite entre o animal e o humano se estendem além dos primatas e envolvem as mais inusitadas espécies zoológicas.Since ancient times, parrots and their allies (Psittacidae) have fascinated Europeans by their striking colors and notable ability to interact with human beings. The discovery of the New World added new species to the international exotic animal trade, which for many centuries had brought beasts to Europe from Africa and the Orient. Lacking large mammals, tropical America participated in this trade with its most appealing species, essentially felines, primates and birds - especially parrots - which were shipped in large numbers. It should be noted, however, that at times these birds were not well liked. In fact, according to documents from colonial Brazil, only the ants rank higher than parrots as the animals most often mentioned as agricultural pests. On the other hand, some of these birds were so chatty that people suspected them to be demonic or possessed animals, since only three classes of beings - angels, men and demons - have the ability to speak. Nowadays, several Psittacidae still constitute a threat to agriculture, and the suspicion that extremely talkative birds were demon possessed has also survived. More than a joke or a mere curiosity, this belief exemplifies how intricate man’s relationships with the “natural world” may be. In this sense, the existence of birds that are able to speak adds a further twist to these relationships, demonstrating that the problem of establishing a boundary between the animal and the human does not only involve primates, but also includes some unusual zoological species