LGBTQ+ Emerging Adults Perceptions of Discrimination and Exclusion within the LGBTQ+ Community

Research on LGBTQ+ emerging adult populations has primarily focused on discrimination that is experienced within the heterodominant culture. Due to systems of oppression and the forces of power and privilege, some sexual and gender minorities experience isolation and discrimination not only within the heterodominant culture, but within the LGBTQ+ community as well. Fourteen lesbian, gay, bisexual, transgender, or queer/questioning (LGBTQ+) young adults (20-25 years) with a diverse array of intersecting identities (e.g., gender, racial, ethnic, religious, cultural) participated in semi-structured individual interviews and focus groups. Participants reported on experiences of biphobia, acephobia, transphobia, gatekeeping the community, LGBTQ+ people of colour’s experiences of racism within the community, other forms of oppression, and offered advice on areas of growth for the LGBTQ+ community. Findings provide insight into LGBTQ+ emerging adults experiences of discrimination and future research implications

Parity-Affected Superconductivity in Ultrasmall Metallic Grains

We investigate the breakdown of BCS superconductivity in {\em ultra}\/small metallic grains as a function of particle size (characterized by the mean spacing $d$ between discrete electronic eigenstates), and the parity ($P$ = even/odd) of the number of electrons on the island. Assuming equally spaced levels, we solve the parity-dependent BCS gap equation for the order parameter $\Delta_P (d,T)$. Both the $T=0$ critical level spacing $d_{c,P}$ and the critical temperature $T_{c,P} (d)$ at which $\Delta_P = 0$ are parity dependent, and both are so much smaller in the odd than the even case that these differences should be measurable in current experiments.Comment: 4 pages RevTeX, 1 encapsulated postscript figure, submitted to Physical Review Letter

Noncommutative quantum mechanics and Bohm's ontological interpretation

We carry out an investigation into the possibility of developing a Bohmian interpretation based on the continuous motion of point particles for noncommutative quantum mechanics. The conditions for such an interpretation to be consistent are determined, and the implications of its adoption for noncommutativity are discussed. A Bohmian analysis of the noncommutative harmonic oscillator is carried out in detail. By studying the particle motion in the oscillator orbits, we show that small-scale physics can have influence at large scales, something similar to the IR-UV mixing

Tunable pentapeptide self-assembled β-sheet hydrogels

Oligopeptide-based supramolecular hydrogels hold promise in a range of applications. The gelation of these systems is hard to control with minor alterations in the peptide sequence significantly influencing the self-assembly process. This makes sequence design difficult whereby typical self-assembly rules cannot be applied. We explored the design of pentapeptide sequences with different charge distributions and discovered that they formed robust, pH-responsive hydrogels. Through altering the concentration and charge distribution of the peptide sequence, we demonstrated that the stiffness of the hydrogels can be tuned across two orders of magnitude (2-200 kPa). Also, through the reassembly of the b-sheet interactions, the hydrogels can both selfheal and shear thin. Using spectroscopic and cryo-imaging techniques, we investigated the relationship between peptide sequence, molecular structure and how these influence the mechanical properties of the hydrogel. These pentapetide hydrogels attributed with tunable morphology and mechanical properties have promise in tissue engineering, injectable delivery vectors and 3D printing applications

Spin Orientation and Spin Precession in Inversion-Asymmetric Quasi Two-Dimensional Electron Systems

Inversion asymmetry induced spin splitting of the electron states in quasi two-dimensional (2D) systems can be attributed to an effective magnetic field B which varies in magnitude and orientation as a function of the in-plane wave vector k||. Using a realistic 8x8 Kane model that fully takes into account spin splitting because of both bulk inversion asymmetry and structure inversion asymmetry we investigate the spin orientation and the effective field B for different configurations of a quasi 2D electron system. It is shown that these quantities depend sensitively on the crystallographic direction in which the quasi 2D system was grown as well as on the magnitude and orientation of the in-plane wave vector k||. These results are used to discuss how spin-polarized electrons can precess in the field B(k||). As a specific example we consider GaInAs-InP quantum wells.Comment: 10 pages, 6 figure

Author Correction: Additive manufacture of complex 3D Au-containing nanocomposites by simultaneous two-photon polymerisation and photoreduction

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has not been fixed in the paper

Multivariate analysis of 3D ToF-SIMS images: method validation and application to cultured neuronal networks

Advanced data analysis tools are crucial for the application of ToF-SIMS analysis to biological samples. Here, we demonstrate that by using a training set approach principal components analysis (PCA) can be performed on large 3D ToF-SIMS images of neuronal cell cultures. The method readily provides access to sample component information and significantly improves the images’ signal-to-noise ratio (SNR)

First principles study of the origin and nature of ferromagnetism in (Ga,Mn)As

The properties of diluted Ga$_{1-x}$Mn$_x$As are calculated for a wide range of Mn concentrations within the local spin density approximation of density functional theory. M\"ulliken population analyses and orbital-resolved densities of states show that the configuration of Mn in GaAs is compatible with either 3d$^5$ or 3d$^6$, however the occupation is not integer due to the large $p$-$d$ hybridization between the Mn $d$ states and the valence band of GaAs. The spin splitting of the conduction band of GaAs has a mean field-like linear variation with the Mn concentration and indicates ferromagnetic coupling with the Mn ions. In contrast the valence band is antiferromagnetically coupled with the Mn impurities and the spin splitting is not linearly dependent on the Mn concentration. This suggests that the mean field approximation breaks down in the case of Mn-doped GaAs and corrections due to multiple scattering must be considered. We calculate these corrections within a simple free electron model and find good agreement with our {\it ab initio} results if a large exchange constant ($N\beta=-4.5$eV) is assumed.Comment: 15 pages, 14 figure

Combined hydrogels that switch human pluripotent stem cells from self-renewal to differentiation

The ability of materials to define the architecture and microenvironment experienced by cells provides new opportunities to direct the fate of human pluripotent stem cells (HPSCs) [Robinton DA, Daley GQ (2012) Nature 481(7381):295–305]. However, the conditions required for self-renewal vs. differentiation of HPSCs are different, and a single system that efficiently achieves both outcomes is not available [Giobbe GG, et al. (2012) Biotechnol Bioeng 109(12):3119–3132]. We have addressed this dual need by developing a hydrogel-based material that uses ionic de-cross-linking to remove a self-renewal permissive hydrogel (alginate) and switch to a differentiation-permissive microenvironment (collagen). Adjusting the timing of this switch can preferentially steer the HPSC differentiation to mimic lineage commitment during gastrulation to ectoderm (early switch) or mesoderm/endoderm (late switch). As an exemplar differentiated cell type, we showed that directing early lineage specification using this single system can promote cardiogenesis with increased gene expression in high-density cell populations. This work will facilitate regenerative medicine by allowing in situ HPSC expansion to be coupled with early lineage specification within defined tissue geometries

Critical Review of Theoretical Models for Anomalous Effects (Cold Fusion) in Deuterated Metals

We briefly summarize the reported anomalous effects in deuterated metals at ambient temperature, commonly known as "Cold Fusion" (CF), with an emphasis on important experiments as well as the theoretical basis for the opposition to interpreting them as cold fusion. Then we critically examine more than 25 theoretical models for CF, including unusual nuclear and exotic chemical hypotheses. We conclude that they do not explain the data.Comment: 51 pages, 4 Figure