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The antibiotic norfloxacin was adsorbed on clay and carbon-clay nanocomposites (MD- 210 and MDac3-210-500, synthesized by hydrothermal carbonization of dextrose) but maintained its antimicrobial activity once adsorbed. To degrade it, direct (DP) and indirect (IP, with sulfate radicals) photolysis were performed. Antimicrobial activity tests were performed to evaluate the degradation generated. There were no significant differences between DP and IP for unabsorbed norfloxacin solution. The IP treatment caused a loss of antibiotic activity in all cases. For DP, the carbon samples showed better results than those of clay, evidencing the importance of oxygenated carbonaceous groups in the photolysis of norfloxacin., Centro de Tecnología de Recursos Minerales y Cerámica, Centro de Investigación y Desarrollo en Fermentaciones Industriales, Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas, Centro de Investigaciones Ópticas

Symbiotic interactions can determine the evolutionary trajectories of host species, influencing genetic variation through selection and changes in demography. In the context of strong selective pressures such as those imposed by infectious diseases, symbionts providing defences could contribute to increase host fitness upon pathogen emergence. Here, we generated genome-wide data of an amphibian species to find evidence of evolutionary pressures driven by two skin symbionts: a batrachochytrid fungal pathogen and an antifungal bacterium. Using demographic modelling, we found evidence of decreased effective population size, probably due to pathogen infections. Additionally, we investigated host genetic associations with infection status, antifungal bacterium abundance and overall microbiome diversity using structural equation models. We uncovered relatively lower nucleotide diversity in infected frogs and potential heterozygote advantage to recruit the candidate beneficial symbiont and fight infections. Our models indicate that environmental conditions have indirect effects on symbiont abundance through both host body traits and microbiome diversity. Likewise, we uncovered a potential offsetting effect among host heterozygosity-fitness correlations, plausibly pointing to different ecological and evolutionary processes among the three species due to dynamic interactions. Our findings revealed that evolutionary pressures not only arise from the pathogen but also from the candidate beneficial symbiont, and both interactions shape the genetics of the host. Our results advance knowledge about multipartite symbiotic relationships and provide a framework to model ecological and evolutionary dynamics in wild populations. Finally, our study approach can be applied to inform conservation actions such as bioaugmentation strategies for other imperilled amphibians affected by infectious diseases.

In this study, high-phosphorus beared microalgae was prepared by cultivating modification in high-phosphorus culture, and used for the enhanced Cd(II) biomineralization in soil. Batch experiment results showed that Chlorella sorokiniana FK was modified successfully in highly phosphate culture. Both intracellular P (Poly-P, 29.7 mg/kg) and surface P (phosphoryl based functional groups, 3.7 mol/kg) were greatly enhanced, and the Cd(II) removal capacity surged to 45.98 mg/g at equilibrium in the Langmuir simulation. The EXAFS analysis indicated that Cd tended to form a more stable bidentate complex (RPO

While some pathogens are limited to single species, others can colonize many hosts, likely contributing to the emergence of novel disease outbreaks. Despite this biodiversity threat, traits associated with host niche expansions are not well understood in multihost pathogens. Here, we aimed to uncover functional machinery driving multihost invasion by focusing on Batrachochytrium dendrobatidis (Bd), a pathogen that infects the skin of hundreds of amphibians worldwide. We performed a meta-analysis of Bd gene expression using data from published infection experiments and newly generated profiles. We analysed Bd transcriptomic landscapes across the skin of 14 host species, reconstructed Bd isolates phylogenetic relationships, and inferred the origin and evolutionary history of differentially expressed genes under a phylogenetic framework comprising other 12 zoosporic fungi. Bd displayed plastic infection strategies when challenged by hosts with different disease susceptibility. Our analyses identified sets of differentially expressed genes under host environments with similar infection outcome. We stressed nutritional immunity and gene silencing as important processes required to overcome challenging skin environments in less susceptible hosts. Overall, Bd genes expressed during amphibian skin exploitation have arisen mainly via gene duplications with great family expansions, increasing the gene copy events previously described for this fungal species. Finally, we provide a comprehensive gene data set that can be used to further examine eco-evolutionary hypotheses for this host-pathogen system. Our study supports the idea that host environments exert contrasting selective pressures, such that gene expression plasticity could be one of the evolutionary keys leading to the success of multihost pathogens.

Background Species adaptation to laboratory conditions is a special case of domestication that has modified model organisms phenotypically and genetically. The characterisation of these changes is crucial to understand how this variation can affect the outcome of biological experiments. Yet despite the wide use of laboratory animals in biological research, knowledge of the genetic diversity within and between different strains and populations of some animal models is still scarce. This is particularly the case of the Mexican axolotl, which has been bred in captivity since 1864. Results Using gene expression data from nine different projects, nucleotide sequence variants were characterised, and distinctive genetic background of the experimental specimens was uncovered. This study provides a catalogue of thousands of nucleotide variants along predicted protein-coding genes, while identifying genome-wide differences between pigment phenotypes in laboratory populations. Conclusions Awareness of the genetic variation could guide a better experimental design while helping to develop molecular tools for monitoring genetic diversity and studying gene functions in laboratory axolotls. Overall, this study highlights the cross-taxa utility that transcriptomic data might have to assess the genetic variation of the experimental specimens, which might help to shorten the journey towards reproducible research.

Cryptic species pose a particular challenge to biologists in the context of life history investigations because of the difficulty in their field discrimination. Additionally, there is normally a lag in their widespread acceptance by the scientific community once they are formally recognised. These two factors might constrain our ability to properly assess the conservation status of the different species conforming a cryptic complex. In this study, we analysed isotopic and genetic data to shed light into the still unclear wintering grounds, population size and evolutionary history of the Iberian chiffchaff (Phylloscopus ibericus), a species included within the Common chiffchaff (Phylloscopus collybita) until two decades ago due to their phenotypic similarity. We used molecular methods to identify spring‐migrating Phylloscopus species captured in northern Iberia, and by comparing the Hydrogen isotopic ratios of their claw tips (δ2Hc; which would reflect the signatures of their wintering grounds), we detected that δ2Hc values of Iberian chiffchaffs were similar to Willow warblers (Phylloscopus trochilus; a renowned trans‐Saharan migrant), and higher than Common chiffchaffs (mostly a pre‐Saharan migrant). These results strongly support the idea that Iberian chiffchaffs winter in tropical Africa. We additionally reconstructed the phylogeny and evolutionary history of the Iberian chiffchaff's clade using mitochondrial and nuclear markers. Our results revealed relatively high values of nucleotide diversity (and, hence, high Ne) for the species that were greater than the values of the Common/Iberian most recent common ancestor. This suggests that the Iberian chiffchaff did not experience strong bottlenecks after diverging from the Common chiffchaff approximately one million years ago. Ultimately, our study provides another illustrative example of how isotopic and genetic analysis tools can help to enhance our understanding of avian ecology and evolution.

Background Gene expression profiles can provide insights into the molecular machinery behind tissue functions and, in turn, can further our understanding of environmental responses, and developmental and evolutionary processes. During vertebrate evolution, the skin has played a crucial role, displaying a wide diversity of essential functions. To unravel the molecular basis of skin specialisations and adaptations, we compared gene expression in the skin with eight other tissues in a phylogenetically and ecologically diverse species sample of one of the most neglected vertebrate groups, the caecilian amphibians (order Gymnophiona). Results The skin of the five studied caecilian species showed a distinct gene expression profile reflecting its developmental origin and showing similarities to other epithelial tissues. We identified 59 sequences with conserved enhanced expression in the skin that might be associated with caecilian dermal specialisations. Some of the up-regulated genes shared expression patterns with human skin and potentially are involved in skin functions across vertebrates. Variation trends in gene expression were detected between mid and posterior body skin suggesting different functions between body regions. Several candidate biologically active peptides were also annotated. Conclusions Our study provides the first atlas of differentially expressed sequences in caecilian tissues and a baseline to explore the molecular basis of the skin functions in caecilian amphibians, and more broadly in vertebrates.

Aquaporins are integral membrane proteins that exchange water and small solutes. They played an important role in the colonisation of terrestrial environments by tetrapod ancestors via the appearance of three exclusive paralogs. Like early tetrapods, mudskippers represent an independent case of amphibious lifestyle evolution that is unparalleled by other extant fish groups. Given this lifestyle parallelism and that aquaporins were relevant for tetrapod terrestrialisation, this study examines the aquaporins in mudskippers to investigate whether similar changes in aquaporins could have possibly occurred during their water-to-land transition. We have catalogued aquaporin genes in four mudskipper genomes and studied their diversity and molecular evolution (including detection of positive selection) in a broad phylogenetic context of vertebrates. Our genomic screening returned 55 aquaporin genes for mudskippers (none of them constituting novel paralogs) that can be assigned to 10 different known classes. We detected signatures of positive selection in AQP10a and AQP11b in mudskippers (both the entire clade and the clade containing the most terrestrial species, implying different evolutionary times). This suggests possible alteration of the molecular function of such paralogs caused by changes at specific protein sequence positions, some of them located in relatively close proximity to parts of the molecule involved in pore formation and substrate selectivity. Given the importance of aquaporins for osmotic regulation in fishes, it might be possible that these selective changes (perhaps allowing permeability to new solutes) could have played a role during the adaptation of mudskippers to an amphibious lifestyle.

espanolEn la actualidad el Estado ecuatoriano ofrece un marco de reconocimiento amplio, respecto de la problematica de la violencia de genero; por lo tanto, los mecanismos establecidos para la proteccion se articulan con distintos ejes; en el eje normativo, se presentan cambios sustanciales derivados del modelo constitucional vigente. Con este antecedente, el presente estudio tiene el proposito de analizar la evolucion normativa ecuatoriana, relacionada con el derecho a una vida libre de violencia. Para el efecto, se realiza un analisis hermeneutico desde la perspectiva historica y descriptiva; desde donde se analiza lo estipulado en la norma fundamental y secundaria, lo que conlleva implicaciones que repercuten en el establecimiento de politicas publicas e institucionalidad de amparo a las victimas. EnglishCurrently, the Ecuadorian State offers a wide recognition framework regarding the problem of gender violence, therefore, the established mechanisms for protection are articulated with different axes; in the normative axis, there are substantial changes derived from the current constitutional model. With this background, the present study has the purpose of analyzing the Ecuadorian normative evolution, related to the right to a life free of violence. For this purpose, a hermeneutic analysis is carried out from the historical and descriptive perspective; from where it is analyzed, what is stipulated in the fundamental and secondary norm, which entails implications that affect the establishment of public policies and institutions for the protection of victims.

Since 1984 there have been no records of Rhaebo colomai (Hoogmoed, 1985) within the territory of Ecuador. This species was known from 2 localities in the province of Carchi, northwestern Ecuador, and the department of Nariño, southwestern Colombia, which were reported in 1979 and 2015, respectively. We report the recent sightings of R. colomai at 3 new localities in Ecuador and discuss and evaluate this species’ extinction risk and conservation status.

International audience; RNA sequencing (RNA-seq) has become one of the most powerful tools to unravel the genomic basis of biological adaptation and diversity. Although challenging, RNA-seq is particularly promising for research on non-model, secretive species that cannot be observed in nature easily and therefore remain comparatively understudied. Among such animals, the caecilians (order Gymnophiona) likely constitute the least known group of vertebrates, despite being an old and remarkably distinct lineage of amphibians. Here, we characterize multi-tissue transcriptomes for five species of caecilians that represent a broad level of diversity across the order. We identified vertebrate homologous elements of caecilian functional genes of varying tissue specificity that reveal a great number of unclassified gene families, especially for the skin. We annotated several protein domains for those unknown candidate gene families to investigate their function. We also conducted supertree analyses of a phylogenomic dataset of 1,955 candidate orthologous genes among five caecilian species and other major lineages of vertebrates, with the inferred tree being in agreement with current views of vertebrate evolution and systematics. Our study provides insights into the evolution of vertebrate protein-coding genes, and a basis for future research on the molecular elements underlying the particular biology and adaptations of caecilian amphibians.