1,308 research outputs found

    Active surveillance for prostate cancer: Is it ready for primetime in the Caribbean?

    Get PDF
    Objective: In this paper we discuss the strategy of active surveillance (AS) as a whole followed by the implications of its use in the Caribbean.Methods: The literature was reviewed with a view to establishing the merits of AS and to identify potential pitfalls in the application of AS among a primarily black population.Results: Active surveillance (AS) has emerged as a viable treatment strategy aimed at reducing overtreat-ment of indolent disease. However, there have been concerns raised over the applicability of AS among men of African descent. Black men are at higher risk of aggressive disease and data are emerging which suggestoutcomes may not parallel those of their white counterparts. Recent advances such as multiparametric MRI and genetic testing have the potential to guide decision making in these men.Conclusion: Active surveillance should not be universally rejected in black men and perhaps further study is needed to determine race-specific recommendations. Until then, discussion with the patient should reflect the potential pitfalls for black men on active surveillance.Keywords: Active surveillance; Caribbean; Africa

    Detection of low energy single ion impacts in micron scale transistors at room temperature

    Get PDF
    We report the detection of single ion impacts through monitoring of changes in the source-drain currents of field effect transistors (FET) at room temperature. Implant apertures are formed in the interlayer dielectrics and gate electrodes of planar, micro-scale FETs by electron beam assisted etching. FET currents increase due to the generation of positively charged defects in gate oxides when ions (121Sb12+, 14+, Xe6+; 50 to 70 keV) impinge into channel regions. Implant damage is repaired by rapid thermal annealing, enabling iterative cycles of device doping and electrical characterization for development of single atom devices and studies of dopant fluctuation effects

    Processing Issues in Top-Down Approaches to Quantum Computer Development in Silicon

    Get PDF
    We describe critical processing issues in our development of single atom devices for solid-state quantum information processing. Integration of single 31P atoms with control gates and single electron transistor (SET) readout structures is addressed in a silicon-based approach. Results on electrical activation of low energy (15 keV) P implants in silicon show a strong dose effect on the electrical activation fractions. We identify dopant segregation to the SiO2/Si interface during rapid thermal annealing as a dopant loss channel and discuss measures of minimizing it. Silicon nanowire SET pairs with nanowire width of 10 to 20 nm are formed by electron beam lithography in SOI. We present first results from Coulomb blockade experiments and discuss issues of control gate integration for sub-40nm gate pitch levels

    Absolute calibration of GafChromic film for very high flux laser driven ion beams.

    Get PDF
    We report on the calibration of GafChromic HD-v2 radiochromic film in the extremely high dose regime up to 100 kGy together with very high dose rates up to 7 × 1011 Gy/s. The absolute calibration was done with nanosecond ion bunches at the Neutralized Drift Compression Experiment II particle accelerator at Lawrence Berkeley National Laboratory (LBNL) and covers a broad dose dynamic range over three orders of magnitude. We then applied the resulting calibration curve to calibrate a laser driven ion experiment performed on the BELLA petawatt laser facility at LBNL. Here, we reconstructed the spatial and energy resolved distributions of the laser-accelerated proton beams. The resulting proton distribution is in fair agreement with the spectrum that was measured with a Thomson spectrometer in combination with a microchannel plate detector

    Careif Position Statement on Migration and Mental Health

    Get PDF
    People have moved from one place to another within the same country or across national borders for millennia. The reasons for such movements have varied, as does the duration for which people migrate. With globalisation and global connections across countries, migration has increased. The process of migration and its impact on the mental health of individuals has been and will remain heterogeneous. The responses of migrants to the process vary, depending upon a number of factors. Individuals may migrate individually, with their families or in groups. They may move to avoid political or religious persecution and seek political asylum in another country (forced migration) or migrate for personal, employment, economic or educational reasons (voluntary migration). Although these two categorisations are often a little more complex than this. Not all migrants will feel negatively affected by migration. People may migrate on a seasonal, recurrent, permanent or temporary basis. It may be within or across generations. Many migrants will never access mental health services, whilst others may use these in varying ways and with diverse requirements or presentations. The experiences and requirements of voluntary and involuntary migrants may differ. Mental health Services may need to ensure that they are accessible and appropriate to all members of society including those who have migrated. This paper makes some suggestions in relation to this

    Early identification of wound infection: understanding wound odour

    Get PDF
    Malodorous wounds can be distressing for patients and their families, negatively impacting on quality-of-life outcomes. For health professionals malodorous wounds can also cause distress manifesting in feelings of disgust when faced with a wound emitting an unpleasant or repulsive odour. There has been investigation into the management of controlling odour particularly in relation to fungating wounds. However, there is limited research that explores techniques for early identification and recognition of wound odours that may be indicative of infection. Electronic nose technology has received some attention, but to date has not been integrated into either diagnostics of infection in wounds or education of health professionals to prepare them for the realities of clinical practice

    Electrical activation and electron spin coherence of ultra low dose antimony implants in silicon

    Full text link
    We implanted ultra low doses (2x10^11 cm-2) of 121Sb ions into isotopically enriched 28Si and find high degrees of electrical activation and low levels of dopant diffusion after rapid thermal annealing. Pulsed Electron Spin Resonance shows that spin echo decay is sensitive to the dopant depths, and the interface quality. At 5.2 K, a spin decoherence time, T2, of 0.3 ms is found for profiles peaking 50 nm below a Si/SiO2 interface, increasing to 0.75 ms when the surface is passivated with hydrogen. These measurements provide benchmark data for the development of devices in which quantum information is encoded in donor electron spins

    Red or green : Overprinting of the climatic signal in Miocene sediments, South China Sea (IODP Expedition 368, Site U1502)

    Get PDF
    Funding Information: Support was provided by Chinese 111 (HW), ECORD (SS), Korean IODP (DC), National Science Foundation (ECF), Natural Environment Research Council (SAB) and U.S. Science Support Program, Lamont‐Doherty Earth Observatory (ECF, PP). Marco Maffione, an anonymous reviewer, the Associate Editor and Max Coleman are kindly acknowledged. Publisher Copyright: © 2023 The Authors. Terra Nova published by John Wiley & Sons Ltd.Peer reviewedPublisher PD
    • 

    corecore