2,942 research outputs found

    Advances in breast cancer treatment and prevention: preclinical studies on aromatase inhibitors and new selective estrogen receptor modulators (SERMs).

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    Intensive basic and clinical research over the past 20 years has yielded crucial molecular understanding into how estrogen and the estrogen receptor act to regulate breast cancer and has led to the development of more effective, less toxic, and safer hormonal therapy agents for breast cancer management and prevention. Selective potent aromatase inhibitors are now challenging the hitherto gold standard of hormonal therapy, the selective estrogen-receptor modulator tamoxifen. Furthermore, new selective estrogen-receptor modulators such as arzoxifene, currently under clinical development, offer the possibility of selecting one with a more ideal pharmacological profile for treatment and prevention of breast cancer. Two recent studies in preclinical model systems that evaluate mechanisms of action of these new drugs and suggestions about their optimal clinical use are discussed

    Learning to ride the high growth “rollercoaster” : the role of publicly funded business accelerator programmes

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    Funding: Welsh Government.High growth firms (HGFs) are a vital determinant of regional economic competitiveness. This paper examines the effectiveness of a Welsh publicly funded business accelerator programme (BAP) designed to nurture HGFs via relational support measures. The paper teases out both the support requirements sought by high growth entrepreneurs, together with the perceived effectiveness of the programme’s offering. Hitherto, the literature has been silent in terms of the mental well-being and psychological resilience of founders of HGFs. This study discovered how mental well-being and psychological resilience of entrepreneurs was very acutely and detrimentally affected when experiencing periods of rapid firm growth. The research also uncovered a disconnect between the support needs of HGFs and those provided by BAPs. To help develop the capabilities and durability of entrepreneurs, “growth readiness” coaching together with psychological resilience training seem appropriate policy measures to help entrepreneurs successfully navigate turbulent episodes of high growth.Peer reviewe

    Trigger points and high growth firms : the vital role of founder “sensing” and “seizing” capabilities

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    The authors wish to acknowledge the funding this research received from the Welsh Government through the Business Wales Accelerated Growth Programme (AGP).Purpose Research on high growth firms (HGFs) is booming yet a strong conceptual understanding of how these firms obtain (and sustain) rapid growth remains (at best) partial. The main purpose of this paper to explore the role founders play in enabling episodes of rapid growth and how they help navigate this process. Design/methodology/approach This paper reports the findings from a qualitative study involving in-depth interviews with entrepreneurs enlisted onto a publicly funded high growth business accelerator programme in Wales. These interviews explored the causes of the firms’ rapid growth, their key growth trigger points, and the organisational consequences of rapid growth. Findings The research reveals that periods of high growth are intrinsically and inextricably inter-linked with the entrepreneurial traits and capabilities of their founders coupled with their ability to “sense” and “seize” pivotal growth opportunities. It also demonstrates founder-level dynamic capabilities enable firms to capitalise on pivotal “trigger points” thereby enabling their progression to a new “dynamic state” in a firm’s temporal evolution. Originality/value The novel approach towards theory building deployed herein is the use of theoretical elaboration as means of extending important existing theoretical constructs such as growth “trigger points” and founder dynamic capabilities. To capitalise on these trigger points, founders have to undergo a process of “temporal transitioning” to effectively manage and execute the growth process in firms. The work also has important policy implications, underlining the need for more relational forms of support for entrepreneurial founders.Peer reviewe

    Hydrogen Balmer Line Broadening in Solar and Stellar Flares

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    The broadening of the hydrogen lines during flares is thought to result from increased charge (electron, proton) density in the flare chromosphere. However, disagreements between theory and modeling prescriptions have precluded an accurate diagnostic of the degree of ionization and compression resulting from flare heating in the chromosphere. To resolve this issue, we have incorporated the unified theory of electric pressure broadening of the hydrogen lines into the non-LTE radiative transfer code RH. This broadening prescription produces a much more realistic spectrum of the quiescent, A0 star Vega compared to the analytic approximations used as a damping parameter in the Voigt profiles. We test recent radiative-hydrodynamic (RHD) simulations of the atmospheric response to high nonthermal electron beam fluxes with the new broadening prescription and find that the Balmer lines are over-broadened at the densest times in the simulations. Adding many simultaneously heated and cooling model loops as a "multithread" model improves the agreement with the observations. We revisit the three-component phenomenological flare model of the YZ CMi Megaflare using recent and new RHD models. The evolution of the broadening, line flux ratios, and continuum flux ratios are well-reproduced by a multithread model with high-flux nonthermal electron beam heating, an extended decay phase model, and a "hot spot" atmosphere heated by an ultrarelativistic electron beam with reasonable filling factors: 0.1%, 1%, and 0.1% of the visible stellar hemisphere, respectively. The new modeling motivates future work to understand the origin of the extended gradual phase emission.Comment: 31 pages, 13 figures, 2 tables, accepted for publication in the Astrophysical Journa

    A central role for TOR signalling in a yeast model for juvenile CLN3 disease

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    Yeasts provide an excellent genetically tractable eukaryotic system for investigating the function of genes in their biological context, and are especially relevant for those conserved genes that cause disease. We study the role of btn1, the orthologue of a human gene that underlies an early onset neurodegenerative disease (juvenile CLN3 disease, neuronal ceroid lipofuscinosis (NCLs) or Batten disease) in the fission yeast Schizosaccharomyces pombe. A global screen for genetic interactions with btn1 highlighted a conserved key signalling hub in which multiple components functionally relate to this conserved disease gene. This signalling hub includes two major mitogen-activated protein kinase (MAPK) cascades, and centers on the Tor kinase complexes TORC1 and TORC2. We confirmed that yeast cells modelling CLN3 disease exhibit features consistent with dysfunction in the TORC pathways, and showed that modulating TORC function leads to a comprehensive rescue of defects in this yeast disease model. The same pathways may be novel targets in the development of therapies for the NCLs and related diseases
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