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The article presents a study which analyzed the influence of an ecologically relevant nonliving variable, pH, on the metabolic allometry of an Australian rainbowfish or Rhadinocentrus ornatus. The relationship of the metabolic rate to body mass of animals is expressed as MR is proportional to Mb where b is a scaling exponent whose value is the subject of debate. The study showed that the value of b is lower for rainbowfish used to acidic conditions compared to those used to alkaline conditions but exposure to altered pH does not change the value of b.

Al2O3 supports were modified by integrating USY zeolites (13.6 wt.%) of various nominal SiO2/Al2O3 molar ratios (30–80). The obtained hybrid solids calcined at 500 °C were impregnated at incipient wetness with a Co–Mo–P solution. After sulfiding with CS2-spiked naphtha (at 230 °C, 5.5 MPa and LHSV=3 h−1) the corresponding catalysts were tested in light straight-run gas oil hydrotreatment at industrially relevant operating conditions. The catalyst containing zeolite of the highest SiO2/Al2O3 molar ratio (80) showed very high hydrodesulfurization activity. Operating at 360 °C, 5.5 MPa and LHSV=2.5 h−1, ultra-low sulfur diesel (∼50 ppm S) could be obtained over that material, from a feedstock of 10,400 ppm S. Medium–strong acidity could be playing an important role on this behaviour by promoting isomerization of sterically hindered organo-sulfur compounds to more favorable configurations. Moreover, hydrodearomatization and hydrodenitrogenation were also enhanced by addition of that high-silica zeolite. [Copyright &y& Elsevier]

Background: Cestodes are a diverse group of parasites, some of them being agents of neglected diseases. In cestodes, little is known about the functional properties of G protein coupled receptors (GPCRs) which have proved to be highly druggable targets in other organisms. Notably, serotoninergic G-protein coupled receptors (5-HT GPCRs) play major roles in key functions like movement, development and reproduction in parasites., Methodology/principal Findings: Three 5-HT GPCRs from Echinococcus granulosus and Mesocestoides corti were cloned, sequenced, bioinformatically analyzed and functionally characterized. Multiple sequence alignment with other GPCRs showed the presence of seven transmembrane segments and conserved motifs but interesting differences were also observed. Phylogenetic analysis grouped these new sequences within the 5-HT7 clade of GPCRs. Molecular modeling showed a striking resemblance in the spatial localization of key residues with their mammalian counterparts. Expression analysis using available RNAseq data showed that both E. granulosus sequences are expressed in larval and adult stages. Localization studies performed in E. granulosus larvae with a fluorescent probe produced a punctiform pattern concentrated in suckers. E. granulosus and M. corti larvae showed an increase in motility in response to serotonin. Heterologous expression revealed elevated levels of cAMP production in response to 5-HT and two of the GPCRs showed extremely high sensitivity to 5-HT (picomolar range). While each of these GPCRs was activated by 5-HT, they exhibit distinct pharmacological properties (5-HT sensitivity, differential responsiveness to ligands)., Conclusions/significance: These data provide the first functional report of GPCRs in parasitic cestodes. The serotoninergic GPCRs characterized here may represent novel druggable targets for antiparasitic intervention.