1,691 research outputs found
Characterization of grain boundaries in silicon
Zero-bias conductance and capacitance measurements at various temperatures were used to study trapped charges and potential barrier height at the boundaries. Deep-level transient spectroscopy (DLTS) was applied to measure the density of states at the boundary. A study of photoconductivity of grain boundaries in p-type silicon demonstrated the applicability of the technique in the measurement of minority carrier recombination velocity at the grain boundary. Enhanced diffusion of phosphorus at grain boundaries in three cast polycrystalline photovoltaic materials was studied. Enhancements for the three were the same, indicating that the properties of boundaries are similar, although grown by different techniques. Grain boundaries capable of enhancing the diffusion were found always to have strong recombination activities; the phenomena could be related to dangling bonds at the boundaries. Evidence that incoherent second-order twins of (111)/(115) type are diffusion-active is presented
Polarization Dependent Coupling of Whispering Gallery Modes in Microspheres
Two sets of resonances in glass microspheres attached to a standard communication-grade single-mode optical fiber have been observed. It has been found that the strength of the resonances depends strongly on the polarization of the coupled light. Furthermore, the position of the resonances in the wavelength domain depends on the polarization of light in the optical fiber with maximum magnitudes shifted by approximately 45
The Impact of Wine Tourism Involvement on Winery Owners' Identity Processes
This is an Accepted Manuscript of an article published by Taylor & Francis in Tourism Planning & Development on 20/02/2020, available online: doi: https://doi.org/10.1080/21568316.2020.1730945This paper examines how involvement in wine tourism has affected winery ownersâ identity processes. Using Breakwellâs Identity Process Theory (IPT) as a conceptual framework, we investigate the extent to which place is a part of winery ownersâ self-identities, thereby giving them senses of belonging, distinctiveness, continuity, and self-esteem. Simultaneously, we find that these senses and feelings influence winery ownersâ perceptions of the benefits and dis-benefits of wine tourism development in their region. We also discover how personal involvement in tourism can strengthen or threaten winery ownersâ identities and thereby affect their support or otherwise for wine tourism. Empirical evidence is provided via a sample of twenty-eight winery owners in Langhe, Italy, who have recently engaged in various tourism-related activities due to the continuous development of the local tourism industry. Our research recognises that place is an integral part of the identity process
New results from an extensive aging test on bakelite Resistive Plate Chambers
We present recent results of an extensive aging test, performed at the CERN
Gamma Irradiation Facility on two single--gap RPC prototypes, developed for the
LHCb Muon System. With a method based on a model describing the behaviour of an
RPC under high particle flux conditions, we have periodically measured the
electrode resistance R of the two RPC prototypes over three years: we observe a
large spontaneous increase of R with time, from the initial value of about 2
MOhm to more than 250 MOhm. A corresponding degradation of the RPC rate
capabilities, from more than 3 kHz/cm2 to less than 0.15 kHz/cm2 is also found.Comment: 6 pages, 7 figures, presented at Siena 2002, 8th Topical Seminar on
Innovative Particle and Radiation Detectors 21-24 October 2002, Siena, Ital
What does the general public understand about prevention and treatment of dementia? A systematic review of population-based surveys
Objectives: To synthesise results of population surveys assessing knowledge and attitudes about prevention and treatment of dementia. Methods: MEDLINE, EMBASE, PsycINFO, and grey literature were searched for English language entries published between 2012 and May 2017. Survey questions were grouped using an inductive approach and responses were pooled. Results: Thirty-four eligible studies and four grey literature items were identified. Surveys were conducted in Europe, the US, Eastern Asia, Israel, and Australia. Nearly half of respondents agreed that dementia is a normal and non-preventable part of ageing, but belief in the potential for prevention may be improving over time. The role of cardiovascular risk factors was poorly understood overall. Less than half of respondents reported belief in the availability of a cure for dementia. The value of seeking treatment was highly endorsed. Conclusions: Results suggest that knowledge about the potential for dementia prevention and treatment remains poor but may be improving over time. Knowledge among those living in low- and middle-income countries are largely unknown, presenting challenges for the development of National action plans consistent with World Health Organization directives.Monica Cations, Gorjana Radisic, Maria Crotty, Kate E. Lave
What characteristics of nursing homes are most valued by consumers? A discrete choice experiment with residents and family members
Objectives: To generate a scoring algorithm weighted on the preferences of consumers for assessing the quality of care in nursing homes (i.e., aged care homes or institutions) in six key domains. Methods: A discrete choice experiment was undertaken with residents of nursing homes (n = 126) or family member proxies (n = 416) in cases where severe cognitive impairment precluded resident participation. Analysis was undertaken using conditional and mixed logit regression models to determine preferences for potential attributes. Results: The findings indicate that all six attributes investigated were statistically significant factors for participants. Feeling at home in the resident's own room was the most important characteristic to both residents and family members. Care staff being able to spend enough time with residents, feeling at home in shared spaces, and staff being very flexible in care routines were also characteristics identified as important for both groups. The results of the Swait-Louviere test rejected the null hypothesis that the estimated parameters between residents and family members were the same, indicating that data from these two groups could not be pooled to generate a single weighted scoring algorithm for the Consumer Choice Index-Six Dimension instrument. Preferences were therefore encapsulated to generate scoring algorithms specific to residents and family members.This study provides important insights into the characteristics of nursing home care that are most valued by consumers. The Consumer Choice Index-Six Dimension instrument may be usefully applied in the evaluation, planning, and design of future services.Rachel Milte, Julie Ratcliffe, Gang Chen, Maria Crott
Resolution of a chronic viral infection after interleukin-10 receptor blockade
A defining characteristic of persistent viral infections is the loss and functional inactivation of antiviral effector T cells, which prevents viral clearance. Interleukin-10 (IL-10) suppresses cellular immune responses by modulating the function of T cells and antigen-presenting cells. In this paper, we report that IL-10 production is drastically increased in mice persistently infected with lymphocytic choriomeningitis virus. In vivo blockade of the IL-10 receptor (IL-10R) with a neutralizing antibody resulted in rapid resolution of the persistent infection. IL-10 secretion was diminished and interferon Îł production by antiviral CD8+ T cells was enhanced. In persistently infected mice, CD8α+ dendritic cell (DC) numbers declined early after infection, whereas CD8αâ DC numbers were not affected. CD8αâ DCs supported IL-10 production and subsequent dampening of antiviral T cell responses. Therapeutic IL-10R blockade broke the cycle of IL-10âmediated immune suppression, preventing IL-10 priming by CD8αâ DCs and enhancing antiviral responses and thereby resolving infection without causing immunopathology
Current cosmological bounds on neutrino masses and relativistic relics
We combine the most recent observations of large-scale structure (2dF and
SDSS galaxy surveys) and cosmic microwave anisotropies (WMAP and ACBAR) to put
constraints on flat cosmological models where the number of massive neutrinos
and of massless relativistic relics are both left arbitrary. We discuss the
impact of each dataset and of various priors on our bounds. For the standard
case of three thermalized neutrinos, we find an upper bound on the total
neutrino mass sum m_nu < 1.0 (resp. 0.6) eV (at 2sigma), using only CMB and LSS
data (resp. including priors from supernovae data and the HST Key Project), a
bound that is quite insensitive to the splitting of the total mass between the
three species. When the total number of neutrinos or relativistic relics N_eff
is left free, the upper bound on sum m_nu (at 2sigma, including all priors)
ranges from 1.0 to 1.5 eV depending on the mass splitting. We provide an
explanation of the parameter degeneracy that allows larger values of the masses
when N_eff increases. Finally, we show that the limit on the total neutrino
mass is not significantly modified in the presence of primordial gravitational
waves, because current data provide a clear distinction between the
corresponding effects.Comment: 13 pages, 6 figure
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