Social justice in translation: subjectivity, identity, and Occidentalism

Volcano plot of differential gene expression in zebrafish retina after optic nerve crush. Each probe on the array is represented by a single dot, with red dots signifying the 804 differentially expressed transcripts. P- values are presented as –log10 values, expression differences presented as log2 fold changes. We set cut off limits at p < 0.05 and absolute fold change ≥1.5. By these parameters, 459 transcripts were over-expressed and 198 were under-expressed after optic nerve injury. (TIFF 64 kb

Additional file 7: Table S4. of Integrated analyses of zebrafish miRNA and mRNA expression profiles identify miR-29b and miR-223 as potential regulators of optic nerve regeneration

Unfiltered enriched GO terms associated with miR-223 predicted target genes sourced from Targetscan Fish database. Table contains each GO category and p-value. (XLSX 9 kb

Conjugated Polymer Nanoparticles by Suzuki–Miyaura Cross-Coupling Reactions in an Emulsion at Room Temperature

A range of stable emulsions of spherical and rod-like conjugated polymer nanoparticles (CPN) were synthesized via Suzuki−Miyaura cross-coupling reactions of 9,9-dioctylfluorene-2,7-diboronic acid bis­(1,3-propanediol) ester with a number of different dibromoarene monomers in xylene, stabilized in water by the nonionic surfactant, Triton X-102. High molar mass poly­(9,9-dioctylfluorene) (PF8), poly­(9,9-dioctylfluorene-<i>alt</i>-benzothiadiazole) (PF8BT), poly­(9,9-dioctylfluorene-<i>alt</i>-4-<i>sec</i>-butylphenyldiphenylamine) (PF8TAA) and poly­(9,9-dioctylfluorene-<i>alt</i>-bithiophene) (PF8T2) emulsions were obtained, at high overall conjugated polymer concentrations (up to 11,000 ppm), in the presence of the palladium complex, (IPr*)­PdCl₂(TEA) and base, tetraethylammonium hydroxide, in nitrogen atmosphere at 30 °C after 24–48 h. TEM analysis of the PF8 and PF8T2 emulsions revealed regular rod-like structures, up to 200 nm in length with aspect ratios of 4–5. PF8BT and PF8TAA formed spherical particles with diameters of between 20–40 nm in TEM analysis. UV–vis absorption spectra of the PF8 emulsions indicated high levels of ordered β-phase configuration (9–10%) in their respective nanoparticles. Absolute photoluminescence quantum yields (Φ) of 21–25% were recorded for these emulsions

Highly charged 180 degree head-to-head domain walls in lead titanate

Charged domain walls (DWs) in ferroelectric materials are an area of intense research. Microscale strain has been identified as a method of inducing arrays of twin walls to meet at right angles, forming needlepoint domains which exhibit novel material properties. Atomic scale characterisation of the features exhibiting these exciting behaviours was inaccessible with the piezoresponse force microscopy resolution of previous work. Here we use aberration corrected scanning transmission electron microscopy to observe short, stepped, highly charged DWs at the tip of the needle points in ferroelectric PbTiO3. Reverse Ti4+ shift polarisation mapping confirms the head-to-head polarisation in adjacent domains. Strain mapping reveals large deviations from the bulk and a wider DW with a high Pb2+ vacancy concentration. The extra screening charge is found to stabilise the DW perpendicular to the opposing polarisation vectors and thus constitutes the most highly charged DW possible in PbTiO3. This feature at the needle point junction is a 5 nm × 2 nm channel running through the sample and is likely to have useful conducting properties. We envisage that similar junctions can be formed in other ferro elastic materials and yield exciting phenomena for future researc

Ferroelectric domain wall memristor

A domain wall-enabled memristor is created, in thin film lithium niobate capacitors, which shows up to twelve orders of magnitude variation in resistance. Such dramatic changes are caused by the injection of strongly inclined conducting ferroelectric domain walls, which provide conduits for current flow between electrodes. Varying the magnitude of the applied electric-field pulse, used to induce switching, alters the extent to which polarization reversal occurs; this systematically changes the density of the injected conducting domain walls in the ferroelectric layer and hence the resistivity of the capacitor structure as a whole. Hundreds of distinct conductance states can be produced, with current maxima achieved around the coercive voltage, where domain wall density is greatest, and minima associated with the almost fully switched ferroelectric (few domain walls). Significantly, this “domain wall memristor” demonstrates a plasticity effect: when a succession of voltage pulses of constant magnitude is applied, the resistance changes. Resistance plasticity opens the way for the domain wall memristor to be considered for artificial synapse applications in neuromorphic circuit