3,064 research outputs found
Morphology of Graphene on SiC(000-1) Surfaces
Graphene is formed on SiC(000-1) surfaces (the so-called C-face of the
crystal) by annealing in vacuum, with the resulting films characterized by
atomic force microscopy, Auger electron spectroscopy, scanning Auger microscopy
and Raman spectroscopy. Morphology of these films is compared with the graphene
films grown on SiC(0001) surfaces (the Si-face). Graphene forms a terraced
morphology on the C-face, whereas it forms with a flatter morphology on the
Si-face. It is argued that this difference occurs because of differing
interface structures in the two cases. For certain SiC wafers, nanocrystalline
graphite is found to form on top of the graphene.Comment: Submitted to Applied Physics Letters; 9 pages, 3 figures; corrected
the stated location of Raman G line for NCG spectrum, to 1596 cm^-
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Nonverbal Behavior During Face-to-face Social Interaction in Schizophrenia
Patients with a diagnosis of schizophrenia display social cognitive deficits. However, little is known about patientsâ nonverbal communication during their social encounters with others. This review identified 17 studies investigating nonverbal communication in patientsâ unscripted face-to-face interactions, addressing a) nonverbal differences between patients and others, b) nonverbal behavior of the patientsâ partners, c) the association between nonverbal behavior and symptoms, and d) the association between nonverbal behavior and social outcomes. Patients displayed fewer nonverbal behaviors inviting interaction, with negative symptoms exacerbating this pattern. Positive symptoms were associated with heightened nonverbal behavior. Patientsâ partners changed their own nonverbal behavior in response to the patient. Reduced prosocial behaviors, inviting interaction, were associated with poorer social outcomes. The evidence suggests that patientsâ nonverbal behavior, during face-to-face interaction, is influenced by patients symptoms and impacts the success of their social interactions
Dissipative and Dispersive Optomechanics in a Nanocavity Torque Sensor
Dissipative and dispersive optomechanical couplings are experimentally
observed in a photonic crystal split-beam nanocavity optimized for detecting
nanoscale sources of torque. Dissipative coupling of up to approximately
MHz/nm and dispersive coupling of GHz/nm enable measurements of sub-pg
torsional and cantilever-like mechanical resonances with a thermally-limited
torque detection sensitivity of 1.2 in ambient conditions and 1.3 in low vacuum. Interference between
optomechanical coupling mechanisms is observed to enhance detection sensitivity
and generate a mechanical-mode-dependent optomechanical wavelength response.Comment: 11 pages, 6 figure
Outbreak of acute hepatitis C following the use of anti-hepatitis C virus--screened intravenous immunoglobulin therapy
BACKGROUND and AIMS: Hepatitis C virus (HCV) infection has been associated with intravenous (IV) immunoglobulin (Ig), and plasma donations used to prepare IV Ig are now screened to prevent transmission. Thirty-six patients from the United Kingdom received infusions from a batch of anti-HCV antibody-screened intravenous Ig (Gammagard; Baxter Healthcare Ltd., Thetford, Norfolk, England) that was associated with reports of acute hepatitis C outbreak in Europe. The aim of this study was to document the epidemiology of this outbreak. METHODS: Forty-six patients from the United Kingdom treated with Gammagard (34 exposed and 12 unexposed to the batch) returned epidemiological questionnaires. RESULTS: Eighty-two percent of the exposed patients (28 of 34) became positive for HCV RNA. Eighteen percent of the patients (6 of 34) who had infusions with this batch tested negative for HCV RNA, but 2 of the patients had abnormal liver function and subsequently seroconverted to anti-HCV antibody positive. Twenty-seven percent of the patients (9 of 34) developed jaundice, and 79% (27 of 34) had abnormal liver transferase levels. Virus isolates (n=21), including an isolate from the implicated batch, were genotype 1a and virtually identical by sequence analysis of the NS5 region, consistent with transmission from a single source. CONCLUSIONS: Hepatitis C infection can be transmitted by anti-HCV-screened IV Ig. Careful documentation of IV Ig batch numbers and regular biochemical monitoring is recommended for all IV Ig recipients
A Categorical Equivalence between Generalized Holonomy Maps on a Connected Manifold and Principal Connections on Bundles over that Manifold
A classic result in the foundations of Yang-Mills theory, due to J. W.
Barrett ["Holonomy and Path Structures in General Relativity and Yang-Mills
Theory." Int. J. Th. Phys. 30(9), (1991)], establishes that given a
"generalized" holonomy map from the space of piece-wise smooth, closed curves
based at some point of a manifold to a Lie group, there exists a principal
bundle with that group as structure group and a principal connection on that
bundle such that the holonomy map corresponds to the holonomies of that
connection. Barrett also provided one sense in which this "recovery theorem"
yields a unique bundle, up to isomorphism. Here we show that something stronger
is true: with an appropriate definition of isomorphism between generalized
holonomy maps, there is an equivalence of categories between the category whose
objects are generalized holonomy maps on a smooth, connected manifold and whose
arrows are holonomy isomorphisms, and the category whose objects are principal
connections on principal bundles over a smooth, connected manifold. This result
clarifies, and somewhat improves upon, the sense of "unique recovery" in
Barrett's theorems; it also makes precise a sense in which there is no loss of
structure involved in moving from a principal bundle formulation of Yang-Mills
theory to a holonomy, or "loop", formulation.Comment: 20 page
Mixed income housing (MIH)
Mixed Income Housing (MIH) is the outcome of a deliberate effort to build a mixed-income development, usually including a variety of housing typologies, sometime combined with the goal of creating a mixed-tenure development. International consensus on a more specific definition of MIH does not exist; instead, multiple expressions can be equally used, with similar meaning. The expression MIH is mainly used within the USA context where it is sometime replaced by mixed-income neighborhood. In Europe, MIH tend to fall within initiatives on (sustainable) urban regeneration, neighborhood restructuring, urban renewal, while the UK legislation often refers to âpepper-pottingâ with respect to different tenures in the same neighborhood aimed to achieve MIH. Non-English-speaking countries tend to use different terms.
The MIH policies are challenged by a specific connotation, i.e., in the United States it is the combination between urban poverty and black or Latinos ghettoes; hence, spatial segregation is combined with racial considerations which are less present in other countries, except for South Africa. In the USA, desegregation in public housing estates became a legal obligation following the famous 1969 Gautreaux case, because of the application of the 1964 Civil Rights Act prohibiting racial discrimination in federally funded activities
Customized television: Standards compliant advanced digital television
This correspondence describes a European Union supported collaborative project called CustomTV based on the premise that future TV sets will provide all sorts of multimedia information and interactivity, as well as manage all such services according to each userâs or group of userâs preferences/profiles. We have demonstrated the potential of recent standards (MPEG-4 and MPEG-7) to implement such a scenario by building
the following services: an advanced EPG, Weather Forecasting, and Stock Exchange/Flight Information
Detection of new point-sources in WMAP Cosmic Microwave Background (CMB) maps at high Galactic latitude. A new technique to extract point sources from CMB maps
In experimental microwave maps, point-sources can strongly affect the
estimation of the power-spectrum and/or the test of Gaussianity of the Cosmic
Microwave Background (CMB) component. As a consequence, their removal from the
sky maps represents a critical step in the analysis of the CMB data. Before
removing a source, however, it is necessary to detect it and source extraction
consists of a delicate preliminary operation. In the literature, various
techniques have been presented to detect point-sources in the sky maps. The
most sophisticated ones exploit the multi-frequency nature of the observations
that is typical of the CMB experiments. These techniques have "optimal"
theoretical properties and, at least in principle, are capable of remarkable
performances. Actually, they are rather difficult to use and this deteriorates
the quality of the obtainable results. In this paper, we present a new
technique, the "weighted matched filter" (WMF), that is quite simple to use and
hence more robust in practical applications. Such technique shows particular
efficiency in the detection of sources whose spectra have a slope different
from zero. We apply this method to three Southern Hemisphere sky regions - each
with an area of 400 square degrees - of the seven years Wilkinson Microwave
Anisotropy Probe (WMAP) maps and compare the resulting sources with those of
the two seven-year WMAP point-sources catalogues. In these selected regions we
find seven additional sources not previously listed in WMAP catalogues and
discuss their most likely identification and spectral properties.Comment: Astronomy and Astrophysics, 2011, in pres
Eliciting perspectives on remote healthcare delivery from service users with psychosis in the community: a cross-sectional survey study.
INTRODUCTION: The transition towards remote healthcare has been rapidly accelerated in recent years due to a number of factors, including the COVID-19 pandemic, however, few studies have explored service users' views of remote mental healthcare, particularly in community mental health settings. METHODS: As part of a larger study concerned with the development of a remotely delivered psychosocial intervention, a survey was conducted with service users with psychosis (Nâ=â200) from six NHS trusts across England to gain cross-sectional data about service users' opinions and attitudes towards remote interventions and explore how digital access varies across different demographic groups and geographical localities. RESULTS: The majority of service users had access to technological devices and a quiet space to receive care. Age was a key factor in motivation to engage with remote care as older participants had less access to technological devices and the internet, and reported less confidence to learn how to use new technologies compared to younger participants. Differences in access and attitudes towards remote care were found across the different geographical localities. Over half of the participants (53.1%) preferred a hybrid model (i.e., mixture of face-to-face and remotely delivered treatment), with only 4.5% preferring remote treatment exclusively. Factors that both encourage and deter service users from engaging with remote care were identified. CONCLUSIONS: The findings of this study provide important information about the environmental and clinical barriers that prevent, or limit, the uptake of remotely delivered care for people with psychotic disorders. Although service users often have the ability and capacity to receive remote care, providers need to be cognisant of factors which may exacerbate digital exclusion and negatively impact the therapeutic alliance
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