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Scratching the surface: a review of online misinformation and conspiracy theories in atopic dermatitis
No full textMisinformation is one of the greatest threats to global health. Atopic dermatitis (AD) is a common skin disorder with a complex multifactorial aetiology, rendering it susceptible to misinformation. Little is known about the content of misinformation regarding AD online. We performed a review of misinformation related to AD available online, via PubMed for scientific papers and via Google for non-scientific websites. Key areas of misinformation were identified, including \u27simple cures\u27 for AD, diet, chemicals, dust, vaccines, red skin syndrome, and alternative therapies. Patients with AD and their families are vulnerable to misinformation given the severe impact of AD on quality of life. Dermatologists must be aware of the false content being shared online related to AD, and be prepared to refute and rebut misinformation by providing appropriate evidence
Taxonomy and ecology of epilithic diatoms in Irish lakes
No full textBenthic algae are significant primary producers and important in biogeochemical cycling in shallow lakes in particular, but epilithic diatom ecology is poorly understood compared to phytoplankton and higher trophic levels. I explored diatom taxonomy and ecology to investigate the suitability of epilithic diatoms for determining the biological condition of Irish lakes. I examined intraspecific variation in populations of two widespread diatom genera to understand the implication of diatom species-complexes for biodiversity and environmental assessments.
Diatom composition in 220 samples from the epilithon of 91 limnologically diverse reference and impacted lakes was analysed, with a replicated spring and summer analysis in my study. Multivariate techniques enabled six characteristic groups of diatom assemblages and their relationship with key abiotic environmental variables to be identified. It revealed that physicochemical gradients of alkalinity-pH, total phosphorus and true colour explained the greatest amount of variation in diatom assemblages in both seasons.
Lake classifications are successful when diatom metrics reliably reflect the response of assemblages to environmental stressor gradients. The Lake Trophic Diatom Index was validated for Water Framework Directive classifications after reference condition was assessed and a highly significant relationship with total phosphorus was identified. This represents an improvement on a previous study that found diatom indices to be poor indicators of trophic condition in Irish lakes. A key finding relative to comparable international studies was that the diatom-phosphorus relationship was not confounded by factors such as lake type. The clearest seasonal pattern that emerged was a consistently low variability in index scores in high status lakes, with variability increasing with declining trophic condition thereafter. Nevertheless, averaging seasonal metric scores provided broadly equivalent levels of explained variation relative to that reported for other phototrophic indices.
The distribution, morphology and ultrastructure of Brachysira and Encyonopsis in a large number of river and lake populations was assessed. Examination of original type material for morphologically challenging Encyonopsis provided new information and taxonomic uncertainty in E. angusta was resolved by a proposed synonymy with E. krammeri. Four new diatom species were described, and greater morphological diversity was discovered. Further validation of nomenclatural types and molecular characterisation is required before many cosmopolitan morphospecies can be formally named. My analyses provided support for the concept of taxonomic redundancy within diatom complexes given the adequate performance of the diatom metric and comparability of species trophic optima when assessed with weighted averaging. However, I also found evidence for differences in ecological niches amongst new and established species that suggested potential for improvements in precision in environmental indices are also achievable.
My study provided a rare example of a contemporary taxonomic investigation for a group of freshwater algae in Irish waters. The broader implication of my findings is that algal diversity in Ireland is actually quite poorly documented. As such, my research provides further opportunities to understand patterns of diatom diversity in the near future. The final chapter of this thesis summarises and discusses the role of diatoms and benthic algal indicators for lake phytobenthos classifications, with suggestions for future research areas
Metformin therapy and severity and mortality of SARS-CoV-2 infection: a meta-analysis
No full textBackground: It has been postulated that metformin could have anti-SARS-CoV-2 action. This raises the hypothesis that people who take metformin may have lower SARS-CoV-2 severity and/or mortality. Objective To conduct a meta-analysis of the association between the use of Metformin and risk of severity and mortality in SARS-CoV-2 infection. Data Sources We searched PubMed, EMBASE, Google scholar, the Cochrane Database of Systematic Reviews and preprint servers (medRxiv and Research Square) for studies published between December 2019 and January 2021. Data was extracted on study location, year of publication, design, number of participants, sex, age at baseline, body mass index, and exposure and outcome definition. Effect statistics were pooled using random effects models with 95% confidence intervals (CI). The quality of included studies was assessed with the Newcastle–Ottawa Scale (NOS). Results Thirty-two observational studies were included, combining to a total sample of 44306 participants. The mean NOS score of included studies was 7.9. Results suggested that metformin use was associated with a reduced risk of SARS-CoV-2 mortality (OR= 0.56, 95% CI: 0.46-0.68, p<0.001; 22 studies) but not to disease severity (OR=0.85, 95% CI: 0.71-1.02, p=0.077; 15 studies). In the subgroup analysis, metformin reduces the risk of mortality (OR = 0.69, 95% CI: 0.55-0.88; p=0.002) and severity (OR = 0.83, 95% CI: 0.70-0.97, p=0.023) in patients aged 70 and above. Conclusions The use of metformin was associated to lower risk of mortality from SARS-CoV-2 infection. This association does not imply causation and further research is required to clarify potential mechanisms
Piezoelectricity of the transmembrane protein ba3 cytochrome c oxidase
No full textControlling the electromechanical response of piezoelectric biological structures including tissues, peptides, and amino acids provides new applications for biocompatible, sustainable materials in electronics and medicine. Here, the piezoelectric effect is revealed in another class of biological materials, with robust longitudinal and shear piezoelectricity measured in single crystals of the transmembrane protein ba3 cytochrome c oxidase from Thermus thermophilus. The experimental findings from piezoresponse force microscopy are substantiated using a range of control measurements and molecular models. The observed longitudinal and shear piezoelectric responses of ≈2 and 8 pm V−1 respectively, are comparable to or exceed the performance of commonly used inorganic piezoelectric materials including quartz,
aluminum nitride, and zinc oxide. This suggests that transmembrane proteins may provide, in addition to physiological energy transduction, technologically useful piezoelectric material derived entirely from nature. Membrane proteins could extend the range of rationally designed biopiezoelectric materials far beyond the minimalistic peptide motifs currently used in miniaturized energy harvesters, and the finding of robust piezoelectric response in a transmembrane protein also raises fundamental questions regarding the molecular evolution, activation, and role of regulatory proteins in the cellular
nanomachinery, indicating that piezoelectricity might be important for fundamental physiological processe
Erebus Volcanic Province: petrology
No full textIgneous rocks of the Erebus Volcanic Province have been investigated for more than a century but many aspects of petrogenesis remain problematic. Current interpretations are assessed and summarized using a comprehensive dataset of previously published and new geochemical and geochronological data. Igneous rocks, ranging in age from 25 Ma to the present day, are mainly nepheline normative. Compositional variation is largely controlled by fractionation of olivine + clinopyroxene + magnetite/ilmenite + titanite ± kaersutite ± feldspar, with relatively undifferentiated melts being generated by <10% partial melting of a mixed spinel + garnet lherzolite source. Equilibration of radiogenic Sr, Nd, Pb and Hf is consistent with a high time-integrated HIMU sensu stricto source component and this is unlikely to be related to subduction of the palaeo-Pacific Plate around 0.5 Ga. Relatively undifferentiated whole-rock chemistry can be modelled to infer complex sources comprising depleted and enriched peridotite, HIMU, eclogite-like and carbonatite-like components. Spatial (west–east) variations in Sr, Nd and Pb isotopic compositions and Ba/Rb and Nb/Ta ratios can be interpreted to indicate increasing involvement of an eclogitic crustal component eastwards. Melting in the region is related to decompression, possibly from edge-driven mantle convection or a mantle plume
Primary cilium-mediated MSC mechanotransduction is dependent on Gpr161 regulation of hedgehog signalling.
No full textThe benefits of physical loading to skeletal mass are well known. The primary cilium has emerged as an important organelle in bone mechanobiology/mechanotransduction, particularly in mesenchymal stem/stromal cells, yet the molecular mechanisms of cilium mechanotransduction are poorly understood. In this study, we demonstrate that Gpr161 is a mechanoresponsive GPCR, that localises to the cilium, and is involved in fluid shear-induced cAMP signalling and downstream osteogenesis. This Gpr161-mediated mechanotransduction is dependent on IFT88/cilium and may act through adenylyl cyclase 6 (AC6) to regulate cAMP and MSC osteogenesis. Moreover, we demonstrate that Hh signalling is positively associated with osteogenesis and that Hh gene expression is mechanically regulated and required for loading-induced osteogenic differentiation through a mechanism that involves IFT88, Gpr161, AC6, and cAMP. Therefore, we have delineated a molecular mechanism of MSC mechanotransduction which likely occurs at the cilium, leading to MSC osteogenesis, highlighting novel mechanotherapeutic targets to enhance osteogenesis
Extensive bacteriocin gene shuffling in the Streptococcus bovis/Streptococcus equinus complex reveals gallocin D with activity against vancomycin resistant enterococci
No full textStreptococcus gallolyticus LL009 produces gallocin D, a narrow spectrum two component bacteriocin
with potent activity against vancomycin-resistant enterococci. Gallocin D is distinct from gallocin
A, a separate two component bacteriocin produced by S. gallolyticus. Although the gene clusters
encoding gallocin A and gallocin D have a high degree of gene synteny, the structural genes are highly
variable and appear to have undergone gene shufing with other streptococcal species. Gallocin D was
analysed in laboratory-based experiments. The mature peptides are 3,343± 1 Da and 3,019 ± 1 Da and
could be readily synthesized and display activity against a vancomycin resistant Enterococcus strain
EC300 with a MIC value of 1.56 µM. Importantly, these bacteriocins could contribute to the ability of S.
gallolyticus to colonize the colon where they have been associated with colorectal cancer.Science Foundation Irelan
Information processing of social exclusion: Links with bullying, moral disengagement and guilt
No full textThe Social Information Processing (SIP) theory and the Social Cognitive Theory of Moral Agency were integrated to investigate the associations between SIP and bullying, guilt, and moral disengagement. Participants were 341 children and early adolescents (Mage = 11.14). Two social exclusion vignettes were administered to assess three SIP steps (step 2: Attribution of hostile intent; step 3: Selection of antisocial goals, and step 4: Generation of aggressive responses). Guilt was assessed through five vignettes. A self-report measure was used to assess moral disengagement and peer nominations were used to assess bullying perpetration. Moderated mediation analyses were performed to test the hypotheses. Findings indicated that attribution of hostile intent was associated with selection of antisocial goals, which in turn, was associated with the generation of aggressive responses among participants with high levels of bullying and low levels of guilt and moral disengagement. Results are discussed in terms of their theoretical and practical relevance
Novel bimodal micro-mesoporous Ni50Co50-LDH/ UiO-66-NH2 nanocomposite for Tl(I) adsorption
No full textNi50Co50-layered double hydroxide/UiO-66-NH2 metal–organic framework nanocomposite (Ni50Co50-LDH/UiO-66-NH2 NC) was synthesized through a facile ultrasonic-assisted hydrothermal method. UiO-66-NH2 MOF nanocrystals were in situ grown on the surface of ultrathin 2-dimensional functionalized Ni50Co50-LDH nanosheets. Using this method, a uniform nanocomposite architecture was obtained by uniformly distributing MOF nanocrystals on Ni50Co50-LDH. The synthesized LDH/MOF NC possesses essential properties of potential nano adsorbent such as high surface area (907 m2 g 1 ), large pore volume (0.91 cm3 g1), bimodal micro mesoporous structure, and chemical functionality. Accordingly, Ni50Co50-LDH/UiO-66-NH2 NC was used as an adsorbent for the uptake of toxic thallium (I) from water. Isotherm, thermodynamic,
and kinetic studies were conducted to gain a better insight into the adsorption mechanism (s) involved in the removal process. Langmuir and pseudo-first-order models present a better fit to the isotherm and kinetic data, respectively, and the maximum Langmuir adsorption capacity was found to be 601.3 mg g 1 after non-linear fitting analysis (pH=7.0, solution volume=30 mL, initial thallium (I) concentration=50 mg L–1, contact time=15 min, solution temperature=293 K
Transformation of inorganic matter in poultry litter during fluidised bed gasification
No full textThis work investigates the transformation, release and fate of inorganic matter during fluidised bed gasification of poultry litter and also poultry litter mixed with limestone as an additive. The poultry litter, the cyclone and bed ash were characterised by means of chemical fractionation analysis, as well as X-ray diffraction. Concurrently, the release of inorganic species during gasification of the feedstock was measured in separate laboratory experiments using molecular beam mass spectrometry. In addition, FactSage was used to predict the formation of gaseous species and the composition of solid residues from gasification under equilibrium conditions. On average, the cyclone ash accounts for 4.6 wt% and the bed ash 12.4 wt% of the total poultry litter fed into the
reactor. All phosphorous (P) was present in the cyclone ash as stable phosphates, while potassium (K) in both cyclone and bed ash was mainly present as H2O leachable KCl, organically associated and stable phosphates and silicates. Furthermore, an assessment was made against the appropriate criteria, whether the ashes gasiication can be categorised as component materials for EU fertiliser product