2,657 research outputs found

    Transport Properties of Carbon Nanotube C60_{60} Peapods

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    We measure the conductance of carbon nanotube peapods from room temperature down to 250mK. Our devices show both metallic and semiconducting behavior at room temperature. At the lowest temperatures, we observe single electron effects. Our results suggest that the encapsulated C60_{60} molecules do not introduce substantial backscattering for electrons near the Fermi level. This is remarkable given that previous tunneling spectroscopy measurements show that encapsulated C60_{60} strongly modifies the electronic structure of a nanotube away from the Fermi level.Comment: 9 pages, 4 figures. This is one of two manuscripts replacing the one orginally submitted as arXiv:cond-mat/0606258. The other one is arXiv:0704.3641 [cond-mat

    National Survey of Lymphedema Therapistsā€™ Dosing of Complete Decongestive Therapy in Breast Cancer Survivors with Lymphedema

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    Purpose: The purpose of this study was to identify dosing levels of complete decongestive therapy (CDT) with survivors with Breast Cancer-Related Lymphedema (BCRL) and describe factors related to how occupational therapists, occupational therapy assistants, physical therapists, and physical therapists assistants with advanced lymphedema training determine dosing. Methods: An electronic survey was sent to 598 occupational therapists, occupational therapy assistants, physical therapists, and physical therapists assistants with training in lymphedema. Respondents completed questions regarding demographics, dosing practices, and factors related to dose determination in complete decongestive therapy of survivors with Breast Cancer-Related Lymphedema. Results: 107 surveys were returned (18% response rate). Most of the respondents (95.1%) reported providing less than the recommended daily dosing (7x/wk) of complete decongestive therapy to their survivors with Breast Cancer-Related Lymphedema. The mean dosing of complete decongestive therapy from respondents was approximately half of the recommended daily dosing (M=3.71). A statistically significant Pearsonā€™s correlation was noted among frequency of dosing and treatment adherence (r=.275) and frequency of dosing and treatment readiness (r=.242). A multiple regression analysis found adherence accounted for a significant proportion of variability in dosing frequency (RĀ²=.077; F change p Conclusions: A majority of therapists treating survivors with Breast Cancer-Related Lymphedema in an outpatient setting are not following daily recommended dosing of complete decongestive therapy. Cliniciansā€™ dose determination is significantly impacted by their perception of a survivorā€™s readiness and adherence to lymphedema treatment and self-management. Comparative clinical outcomes studies of various therapeutic dosage levels (times per week) and duration (length of delivery) of complete decongestive therapy are imperative for development of best treatment protocols for survivors with Breast Cancer-Related Lymphedema. This study serves as a first step toward evidence based planning for complete decongestive therapy treatment of Breast Cancer-Related Lymphedema

    Time-resolved broadband analysis of slow-light propagation and superluminal transmission of electromagnetic waves in three-dimensional photonic crystals

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    A time-resolved analysis of the amplitude and phase of THz pulses propagating through three-dimensional photonic crystals is presented. Single-cycle pulses of THz radiation allow measurements over a wide frequency range, spanning more than an octave below, at and above the bandgap of strongly dispersive photonic crystals. Transmission data provide evidence for slow group velocities at the photonic band edges and for superluminal transmission at frequencies in the gap. Our experimental results are in good agreement with finite-difference-time-domain simulations.Comment: 7 pages, 11 figure

    Mars Rover Sample Return: A sample collection and analysis strategy for exobiology

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    For reasons defined elsewhere it is reasonable to search for biological signatures, both chemical and morphological, of extinct life on Mars. Life on Earth requries the presence of liquid water, therefore, it is important to explore sites on Mars where standing bodies of water may have once existed. Outcrops of layered deposits within the Valles Marineris appear to be ancient lake beds. Because the outcrops are well exposed, relatively shallow core samples would be very informative. The most important biological signature to detect would be organics, microfossils, or larger stromato-like structures, although the presence of cherts, carbonates, clays, and shales would be significant. In spite of the limitations of current robotics and pattern recognition, and the limitations of rover power, computation, Earth communication bandwidth, and time delays, a partial scenario was developed to implement such a scientific investigation. The rover instrumentation and the procedures and decisions and IR spectrometer are described in detail. Preliminary results from a collaborative effort are described, which indicate the rover will be able to autonomously detect stratification, and hence will ease the interpretation burden and lead to greater scientific productivity during the rover's lifetime

    Manipulating prohibitin levels provides evidence for an in vivo role in androgen regulation of prostate tumours

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    Current hormonal therapies for prostate cancer are effective initially, but inevitably tumours progress to an advanced, metastatic stage, often referred to as ā€˜androgen independentā€™. However, the androgen receptor (AR) signalling pathway is still key for their growth. It is speculated that tumours escape hormonal control via reduction in corepressor proteins. Manipulating such proteins is thus a potential therapeutic strategy to halt or even reverse tumour progression. We aimed to elucidate the effects of altering levels of the AR corepressor and androgen-target protein prohibitin (PHB) on prostate tumour growth. Prostate cancer cells incorporating an integrated androgen-responsive reporter gene and stably expressing vectors to inducibly overexpress or knockdown PHB were generated and used to assess effects on androgen signalling (by real time imaging) and tumour growth both in culture and in vivo. PHB overexpression inhibited AR activity and prostate-specific antigen (PSA) expression as well as androgen-dependent growth of cells, inducing rapid accumulation in G0/G1. Conversely, reduction in PHB increased AR activity, PSA expression, androgen-mediated growth and S-phase entry. In vivo, doxycycline-induced PHB regulation resulted in marked changes in AR activity, and showed significant effects upon tumour growth. Overexpression led to tumour growth arrest and protection from hormonal starvation, whereas RNAi knockdown resulted in accelerated tumour growth, even in castrated mice. This study provides proof of principle that i) reduction in PHB promotes both androgen-dependent and ā€˜androgen-independentā€™ tumour growth, and ii) altering AR activity via increasing levels or activity of corepressors is a valid therapeutic strategy for advanced prostate cancer

    Transport through an impurity tunnel coupled to a Si/SiGe quantum dot

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    Achieving controllable coupling of dopants in silicon is crucial for operating donor-based qubit devices, but it is difficult because of the small size of donor-bound electron wavefunctions. Here we report the characterization of a quantum dot coupled to a localized electronic state, and we present evidence of controllable coupling between the quantum dot and the localized state. A set of measurements of transport through this device enable the determination of the most likely location of the localized state, consistent with an electronically active impurity in the quantum well near the edge of the quantum dot. The experiments we report are consistent with a gate-voltage controllable tunnel coupling, which is an important building block for hybrid donor and gate-defined quantum dot devices.Comment: 5 pages, 3 figure

    Marketing madness or financial folly?: Implementing equity crowdfunding in the record industry

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    Purpose The purpose of this paper is to explore the implementation of equity crowdfunding (ECF) within the record industry in terms of challenges and opportunities, in addition to the marketing and financial implications for independent music artists and major record labels. Design/methodology/approach This study adopted a qualitative methodology consisting of two-stage interview-based research methods. A total of 44 semi-structured in-depth interviews were conducted with the CEOs of ECF platforms in the record industry, other related record industry informants, independent artist managers and senior executives from major record labels. Findings The loyalty aspect of ECF may have significant marketing potential in terms of inconspicuously using the equity platform as a ā€œprosumerā€ identification mechanism. As this early career stage of artists is delicate in terms of establishing trust and patronage from their fans, these early marketing and ECF ventures should be implemented directly from the artist without external third-party involvement. Research limitations/implications The implications of this paperā€™s findings and theoretical model are not limited to the two studied stakeholder groups of the record industry. The insights in relation to the obstinate lack of understanding and clarity (particularly for independent artists) which surround ECF are likely to influence short-term strategic approaches by other players throughout the wider music industry. Practical implications The insights regarding negative approaches towards ECF by the labels may influence future ā€œcoopetition strategiesā€ for independent labels, as they seek to navigate the changing industry dynamics. Originality/value This paper is the first study to empirically explore the predominantly under-researched area of ECF implementation in the record industry in terms of marketing and financial consequences for artists and labels. </jats:sec
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