Ordering intermetallic alloys by ion irradiation: a way to tailor magnetic media

Combining He ion irradiation and thermal mobility below 600K, we both trigger and control the transformation from chemical disorder to order in thin films of an intermetallic ferromagnet (FePd). Kinetic Monte Carlo simulations show how the initial directional short range order determines order propagation. Magnetic ordering perpendicular to the film plane was achieved, promoting the initially weak magnetic anisotropy to the highest values known for FePd films. This post-growth treatment should find applications in ultrahigh density magnetic recording.Comment: 7 pages, 3 Figure

Sigma1 Targeting to Suppress Aberrant Androgen Receptor Signaling in Prostate Cancer.

Suppression of androgen receptor (AR) activity in prostate cancer by androgen depletion or direct AR antagonist treatment, although initially effective, leads to incurable castration-resistant prostate cancer (CRPC) via compensatory mechanisms including resurgence of AR and AR splice variant (ARV) signaling. Emerging evidence suggests that Sigma1 (also known as sigma-1 receptor) is a unique chaperone or scaffolding protein that contributes to cellular protein homeostasis. We reported previously that some Sigma1-selective small molecules can be used to pharmacologically modulate protein homeostasis pathways. We hypothesized that these Sigma1-mediated responses could be exploited to suppress AR protein levels and activity. Here we demonstrate that treatment with a small-molecule Sigma1 inhibitor prevented 5α- dihydrotestosterone-mediated nuclear translocation of AR and induced proteasomal degradation of AR and ARV, suppressing the transcriptional activity and protein levels of both full-length and splice-variant AR. Consistent with these data, RNAi knockdown of Sigma1 resulted in decreased AR levels and transcriptional activity. Furthermore, Sigma1 physically associated with ARV7 and A

Chemical ordering in magnetic FePd / Pd(001) epitaxial thin films induced by annealing

Chemically disordered FePd epitaxial layers are grown at room temperature by molecular beam epitaxy on a Pd(001) buffer layer and then annealed in order to induce the chemically ordered L10 (AuCu I) structure. Contrary to what is observed in the case of ordering during growth above room temperature, the ordered structure appears here with the three possible variants of the L10 phase. The ratio of the three different variant volumes is set by the residual epitaxial strain in the layer before annealing. It thus explains that for long annealing times, the long-range order parameter associated with the L10 variant with c along the (100) growth direction saturates at a value close to 0.65, and never reaches unity. Magnetic consequences of the ordering are studied

The role of the microbiome in cancer and therapy efficacy: Focus on lung cancer

The microbiome is extremely important for human health; more recently its role in the context of cancer became clear. Microbial effects range from enhancing cancer immunity and cancer therapy efficacy, to promoting cancer progression and inhibiting treatment efficacy. These broad implications led researchers to investigate these specific interactions, as well as how modification of the microbiome can improve cancer survival and treatment efficacy. While these interactions are better established for cancers such as gastric cancer, they are far less understood in others. As non-small cell lung cancer (NSCLC) makes up the majority of lung cancer cases, and is among the top causes of cancer deaths worldwide, understanding the mechanisms by which the microbiome may impact progression and treatment is crucial to improve patient survival and treatment response. A literature review was conducted to reveal the crosslink between human microbiome and lung cancer. This includes immune priming, induction of pro- or anti-tumor response

FGF Signalling Regulates Chromatin Organisation during Neural Differentiation via Mechanisms that Can Be Uncoupled from Transcription

Changes in higher order chromatin organisation have been linked to transcriptional regulation; however, little is known about how such organisation alters during embryonic development or how it is regulated by extrinsic signals. Here we analyse changes in chromatin organisation as neural differentiation progresses, exploiting the clear spatial separation of the temporal events of differentiation along the elongating body axis of the mouse embryo. Combining fluorescence in situ hybridisation with super-resolution structured illumination microscopy, we show that chromatin around key differentiation gene loci Pax6 and Irx3 undergoes both decompaction and displacement towards the nuclear centre coincident with transcriptional onset. Conversely, down-regulation of Fgf8 as neural differentiation commences correlates with a more peripheral nuclear position of this locus. During normal neural differentiation, fibroblast growth factor (FGF) signalling is repressed by retinoic acid, and this vitamin A derivative is further required for transcription of neural genes. We show here that exposure to retinoic acid or inhibition of FGF signalling promotes precocious decompaction and central nuclear positioning of differentiation gene loci. Using the Raldh2 mutant as a model for retinoid deficiency, we further find that such changes in higher order chromatin organisation are dependent on retinoid signalling. In this retinoid deficient condition, FGF signalling persists ectopically in the elongating body, and importantly, we find that inhibiting FGF receptor (FGFR) signalling in Raldh2−/− embryos does not rescue differentiation gene transcription, but does elicit both chromatin decompaction and nuclear position change. These findings demonstrate that regulation of higher order chromatin organisation during differentiation in the embryo can be uncoupled from the machinery that promotes transcription and, for the first time, identify FGF as an extrinsic signal that can direct chromatin compaction and nuclear organisation of gene loci

Flavor Democracy in Standard Models at High Energies

It is possible that the standard model (SM) is replaced around some transition energy \E_{tr} by a new, possibly Higgsless, ``flavor gauge theory'' such that the Yukawa (running) parameters of SM at E \sim \E_{tr} show up an (approximate) flavor democracy (FD). We investigate the latter possibility by studying the renormalization group equations for the Yukawa couplings of SM with one and two Higgs doublets, by evolving them from given physical values at low energies ($E \simeq 1 GeV$) to \E_{tr} ( \sim \E_{pole}) and comparing the resulting fermion masses and CKM matrix elements at E \simeq \E_{tr} for various $m_t^{phy}$ and ratios $v_u/v_d$ of vacuum expectation values. We find that the minimal SM and the closely related SM with two Higgs doublets (type I) show increasing deviation from FD when energy is increased, but that SM with two Higgs doublets (type II) clearly tends to FD with increasing energy - in both the quark and the leptonic sector (q-q and l-l FD). Furthermore, we find within the type II model that, for \E_{pole} \ll \E_{Planck}, $m_t^{phy}$ can be less than $200 GeV$ in most cases of chosen $v_u/v_d$. Under the assumption that also the corresponding Yukawa couplings in the quark and the leptonic sector at E \simeq \E_{tr} are equal (l-q FD), we derive estimates of bounds on masses of top quark and tau-neutrino, which are compatible with experimental bounds.Comment: 23 pages (7 Figs. available on request), standard LATEX, preprint DO-TH 93-08, SNUTP 93-12, YUMS 93-0

Maximising transparency in a doctoral thesis: The complexities of writing about the use of QSR*NVIVO within a grounded theory study

This paper discusses the challenges of how to provide a transparent account of the use of the software programme QSR*NVIVO (QSR 2000) within a Grounded Theory framework (Glaser and Strauss 1967; Strauss and Corbin 1998). Psychology students are increasingly pursuing qualitative research projects such to the extent that the UK Economic and Social Research Council (ESRC) advise that students should have skill in the use of computer assisted qualitative data analysis software (CAQDAS) (Economic and Social Research Council 2001). Unlike quantitative studies, rigid formulae do not exist for writing-up qualitative projects for doctoral theses. Most authors, however, agree that transparency is essential when communicating the findings of qualitative research. Sparkes (2001) recommends that evaluative criteria for qualitative research should be commensurable with the aims, objectives, and epistemological assumptions of the research project. Likewise, the use of CAQDAS should vary according to the research methodology followed, and thus researchers should include a discussion of how CAQDAS was used. This paper describes how the evolving process of coding data, writing memos, categorising, and theorising were integrated into the written thesis. The structure of the written document is described including considerations about restructuring and the difficulties of writing about an iterative process within a linear document

Disordered gaming in esports: comparing professional and non-professional gamers

The American Psychiatric Association (APA) proposed ‘Internet Gaming Disorder’ (IGD) as a tentative disorder (APA framework) in 2013 and in 2019 the World Health Organization (WHO) has fully recognized ‘Gaming Disorder’ (GD) as a mental health disorder (WHO framework). These two frameworks have not yet been jointly investigated in the context of esports. The present study aims to investigate the feasibility of the APA and WHO frameworks for disordered gaming among professional and non-professional gamers and to ascertain the suitability of existing psychometric tools for use in esports. Methods: A sample of 5,734 gamers (Mage = 21.47 years, SD = 6.69 years; 6.94% female) recruited through an online survey prior to the COVID-19 pandemic that included an age and gender matched group of professional (n = 2,867) and non-professional gamers (n = 2,867) was investigated. Pairwise comparisons, measurement invariance (MI), and latent mean difference tests were conducted to distinguish the two groups of gamers. Results: Overall, professional gamers showed greater time spent gaming and prevalence of disordered gaming than non-professional gamers. Additionally, MI was supported and both disordered gaming levels and latent means were significantly higher among professional gamers when compared to non-professional gamers across both APA and WHO frameworks. Conclusions: Esports is cross-sectionally associated with greater disordered gaming vulnerability through increased time spent gaming and disordered gaming prevalence rates. Furthermore, the APA and WHO frameworks are viable in the context of esports gaming with existing assessment tools being effective in the assessment of disordered gaming in esports. The results and implications are further discussed in light of the extant literature