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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
Social and ecological responsibility within engineering education. A modular student-driven course design that is implemented at seven German universities
No full textThe Blue Engineering Course is a student-initiated course design that addresses the social and ecological responsibility of engineering. Its student-driven character is achieved through a set of over 150 building blocks, these are well-documented teaching/learning units which are freely available online. The course consists of three parts so that the students gradually acquire the competences to co-conduct and co-develop the course: 1) Students get to know high quality building blocks conducted by a lecturer/student tutors; 2) Students conduct existing building blocks; 3) Students develop new building blocks, conduct them and document them for future use.The design of the Blue Engineering Course has been implemented at Technische Universität Berlin since 2011. Here, over 100 students participated in 18 consecutive semesters. The course design is also successfully adapted and implemented at six other universities in Germany. In total, four exemplary implementations are presented and than analyzed with regard to the transferability and success factors of its implementation
An investigation of the variation of dielectric properties of ovine lung tissue with temperature
No full textPresently, lung cancer is the leading cause of cancer deaths. Microwave thermal ablation is commonly used for the treatment of lung cancer. During microwave ablation treatment, changing temperatures (up to 100 °C) cause variations in the dielectric properties of the tissue under treatment. This study investigates the temperature dependence of dielectric properties of ex-vivo ovine lung tissue. The frequency spectrum investigated was from 0.5 GHz to 8 GHz over a total of 201 points. In this study, a microwave ablator (MWA) and a microwave oven (MWO) were used to warm up the samples under investigation. Initially, the spectral variation of the dielectric properties with temperature are presented. The results show that both the real part of the permittivity and the conductivity decrease with temperature for both heating methodologies. The study also investigates the effect of the heating methodology on the measurements. In this case, MWA heating results in a wider range in the measured dielectric parameters compared to MWO. However, the average values for both methodologies are within experimental uncertainty. Finally, the study also presents the temperature coefficients for both the MWA and the MWO tissue heating methods. These results are useful in treatment planning of thermal ablation procedures in order to minimise thermal damage to peripheral tissue.This work has received funding from the European
Research Council under the European Union\u27s Horizon 2020
Programme/ERC Grant Agreement BioElecPro n. 637780,
and has been developed within the framework of COST
Action MiMed (TD1301)
The complex roles of efferocytosis in cancer development, metastasis, and treatment
No full textWhen tumor cells are killed by targeted therapy, radiotherapy, or chemotherapy, they trigger their primary tumor by releasing pro-inflammatory cytokines. Microenvironmental interactions can also promote tumor heterogeneity and development. In this line, several immune cells within the tumor microenvironment, including macrophages, dendritic cells, regulatory T-cells, and CD8+ and CD4+ T cells, are involved in the clearance of apoptotic tumor cells through a process called efferocytosis. Although the efficiency of apoptotic tumor cell efferocytosis is positive under physiological conditions, there are controversies regarding its usefulness in treatment-induced apoptotic tumor cells (ATCs). Efferocytosis can show the limitation of cytotoxic treatments, such as chemotherapy and radiotherapy. Since cytotoxic treatments lead to extensive cell mortality, efferocytosis, and macrophage polarization toward an M2 phenotype, the immune response may get involved in
tumor recurrence and metastasis. Tumor cells can use the anti-inflammatory effect of apoptotic tumor cell efferocytosis to induce an immunosuppressive condition that is tumor-tolerant. Since M2 polarization and efferocytosis are tumor-promoting processes, the receptors on macrophages act as potential targets for cancer therapy. Moreover, researchers have shown that efferocytosis-related molecules/pathways are potential targets for cancer therapy. These include phosphatidylserine and calreticulin, Tyro3, Axl, and Mer tyrosine kinase (MerTK), receptors of tyrosine kinase, indoleamine-2,3-dioxygenase 1, annexin V, CD47, TGF-β, IL-10, and macrophage phenotype switch are combined with conventional therapy, which can be more effective in cancer treatment. Thus, we set out to investigate the advantages and disadvantages of efferocytosis in treatment-induced apoptotic tumor cells