254 research outputs found
Sociodemographic factors and patient perceptions are associated with attitudes to kidney transplantation among haemodialysis patients
Background. Treatment decisions made by patients with chronic kidney disease are crucial in the renal transplantation process. These decisions are influenced, amongst other factors, by attitudes towards different treatment options, which are modulated by knowledge and perceptions about the disease and its treatment and many other subjective factors. Here we study the attitude of dialysis patients to renal transplantation and the association of sociodemographic characteristics, patient perceptions and experiences with this attitude.
Methods. In a cross-sectional study, all patients from eight dialysis units in Budapest, Hungary, who were on haemodialysis for at least 3 months were approached to complete a self-administered questionnaire. Data collected from 459 patients younger than 70 years were analysed in this manuscript.
Results. Mean age of the study population was 53 +/- 12 years, 54% were male and the prevalence of diabetes was 22%. Patients with positive attitude to renal transplantation were younger (51 +/- 11 versus 58 +/- 11 years), better educated, more likely to be employed (11% versus 4%) and had prior transplantation (15% versus 7%)(P < 0.05 for all). In a multivariate model, negative patient perceptions about transplantation, negative expectations about health outcomes after transplantation and the presence of fears about the transplant surgery were associated, in addition to incre- asing age, with unwillingness to consider transplantation.
Conclusions. Negative attitudes to renal transplantation are associated with potentially modifiable factors. Based on this we suggest that it would be necessary to develop standardized, comprehensible patient information systems and personalized decision support to facilitate modality selection and to enable patients to make fully informed treatment decisions
Percolation on the average and spontaneous magnetization for q-states Potts model on graph
We prove that the q-states Potts model on graph is spontaneously magnetized
at finite temperature if and only if the graph presents percolation on the
average. Percolation on the average is a combinatorial problem defined by
averaging over all the sites of the graph the probability of belonging to a
cluster of a given size. In the paper we obtain an inequality between this
average probability and the average magnetization, which is a typical extensive
function describing the thermodynamic behaviour of the model
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dh+CU: Future Directions for Digital Humanities at CU Boulder
Digital Humanities (DH) work harnesses digital technologies to disseminate, analyze and synthesize information in new and innovative ways, often to answer humanistic questions, and may make use of tools like visualization, text mining and statistical tools. The Libraries’ Digital Humanities Task Force was formed to investigate and report on DH activities and needs on campus and formulate recommendations for how the Libraries might help support these needs in tandem with campus partners. We take a broad view of DH and were as inclusive as possible in all of these activities – the disciplinary affiliation of the scholar engaging in these activities (humanities, social sciences or sciences) is irrelevant. In this context, DH is not a circumscribed concept but rather a broad set of methodologies and approaches that loom large in the realm of support and participation libraries and their staff can offer to users undertaking digital scholarship.
The Task Force undertook several major activities to meet these goals. Among them are: an investigation of library-associated DH initiatives at other institutions; an environmental scan of campus facilities and services; a campus-wide survey (345 responses); in-depth interviews with 20 faculty, graduate students and other campus researchers; additional interviews with those involved in external DH initiatives; and presentations and feedback during the DH symposium and workshop held in August 2013. Our research showed that DH work was of broad interest to graduate students and faculty on campus across disciplinary boundaries
The Northwest Tropical Atlantic Station (NTAS) : NTAS-3 mooring turnaround cruise report
The Northwest Tropical Atlantic Station (NTAS) was established to address the
need for accurate air-sea flux estimates and upper ocean measurements in a region with
strong sea surface temperature anomalies and the likelihood of significant local air–sea
interaction on interannual to decadal timescales. The approach is to maintain a surface
mooring outfitted for meteorological and oceanographic measurements at a site near
15°N, 51°W by successive mooring turnarounds. These observations will be used to
investigate air–sea interaction processes related to climate variability.
Deployment of the first (NTAS-1) and second (NTAS-2) moorings were
documented in previous reports (Plueddemann et al., 2001, 2002). This report documents
recovery of the NTAS-2 mooring and deployment of the NTAS-3 mooring at the same
site. Both moorings used 3-meter discus buoys as the surface element. These buoys were
outfitted with two Air–Sea Interaction Meteorology (ASIMET) systems. Each system
measures, records, and transmits via Argos satellite the surface meteorological variables
necessary to compute air–sea fluxes of heat, moisture and momentum. The upper 150 m
of the mooring line were outfitted with oceanographic sensors for the measurement of
temperature and velocity.
The mooring turnaround was done on the WHOI R/V Oceanus, Cruise OC-385-5,
by the Upper Ocean Processes Group of the Woods Hole Oceanographic Institution. The
cruise took place between 12 and 23 February 2003. Deployment of the NTAS-3 mooring
was on 15 February at approximately 14°49.5¢ N, 51°01.3¢ W in 4977 m of water. A 24-
hour intercomparison period followed, after which the NTAS-2 mooring was recovered.
This report describes these operations, as well as some of the pre-cruise buoy
preparations.Funding was provided by the National Oceanic and Atmospheric Administration
under Grant Number NA17RJ1223
Extreme mass ratio inspiral rates: dependence on the massive black hole mass
We study the rate at which stars spiral into a massive black hole (MBH) due
to the emission of gravitational waves (GWs), as a function of the mass M of
the MBH. In the context of our model, it is shown analytically that the rate
approximately depends on the MBH mass as M^{-1/4}. Numerical simulations
confirm this result, and show that for all MBH masses, the event rate is
highest for stellar black holes, followed by white dwarfs, and lowest for
neutron stars. The Laser Interferometer Space Antenna (LISA) is expected to see
hundreds of these extreme mass ratio inspirals per year. Since the event rate
derived here formally diverges as M->0, the model presented here cannot hold
for MBHs of masses that are too low, and we discuss what the limitations of the
model are.Comment: Accepted to CQG, special LISA issu
Growing Massive Black Holes in a Local Group Environment: the Central Supermassive, Slowly Sinking, and Ejected Populations
We explore the growth of < 10^7 Msun black holes that reside at the centers
of spiral and field dwarf galaxies in a Local Group type of environment. We use
merger trees from a cosmological N-body simulation known as Via Lactea II
(VL-2) as a framework to test two merger-driven semi-analytic recipes for black
hole growth that include dynamical friction, tidal stripping, and gravitational
wave recoil in over 20,000 merger tree realizations. First, we apply a
Fundamental Plane limited (FPL) model to the growth of Sgr A*, which drives the
central black hole to a maximum mass limited by the Black Hole Fundamental
Plane after every merger. Next, we present a new model that allows for
low-level Prolonged Gas Accretion (PGA) during the merger. We find that both
models can generate a Sgr A* mass black hole. We predict a population of
massive black holes in local field dwarf galaxies - if the VL-2 simulation is
representative of the growth of the Local Group, we predict up to 35 massive
black holes (< 10^6 Msun) in Local Group field dwarfs. We also predict that
hundreds of < 10^5 Msun black holes fail to merge, and instead populate the
Milky Way halo, with the most massive of them at roughly the virial radius. In
addition, we find that there may be hundreds of massive black holes ejected
from their hosts into the nearby intergalactic medium due to gravitational wave
recoil. We discuss how the black hole population in the Local Group field
dwarfs may help to constrain the growth mechanism for Sgr A*.Comment: 25 pages, 19 figures, accepted for publication in MNRA
The Epstein-Barr Virus Polymerase Accessory Factor BMRF1 Adopts a Ring-shaped Structure as Visualized by Electron Microscopy
Epstein-Barr virus (EBV) encodes a set of core replication factors used during lytic infection in human cells that parallels the factors used in many other systems. These include a DNA polymerase and its accessory factor, a helicase/primase, and a single strand binding protein. The EBV polymerase accessory factor has been identified as the product of the BMRF1 gene and has been shown by functional assays to increase the activity and processivity of the polymerase. Unlike other members of this class of factors, BMRF1 is also a transcription factor regulating certain EBV genes. Although several polymerase accessory factors, including eukaryotic proliferating cell nuclear antigen, Escherichia coli beta protein, and T4 gene 45 protein have been shown to form oligomeric rings termed sliding clamps, nothing is known about the oligomeric state of BMRF1 or whether it forms a ring. In this work, BMRF1 was purified directly from human cells infected with an adenovirus vector expressing the BMRF1 gene product. The protein was purified to near homogeneity, and examination by negative staining electron microscopy revealed large, flat, ring-shaped molecules with a diameter of 15.5 +/- 0.8 nm and a distinct 5.3-nm diameter hole in the center. The size of these rings is consistent with an oligomer of 6 monomers, nearly twice as large as the trimeric proliferating cell nuclear antigen ring. Unlike the herpes simplex virus UL42 homologue, BMRF1 was found to self-associate in solution. These findings extend the theme of polymerase accessory factors adopting ring-shaped structures and provide an example in which the ring is significantly larger than any previously described sliding clamp
First Steps towards Underdominant Genetic Transformation of Insect Populations
The idea of introducing genetic modifications into wild populations of insects to stop them from spreading diseases is more than 40 years old. Synthetic disease refractory genes have been successfully generated for mosquito vectors of dengue fever and human malaria. Equally important is the development of population transformation systems to drive and maintain disease refractory genes at high frequency in populations. We demonstrate an underdominant population transformation system in Drosophila melanogaster that has the property of being both spatially self-limiting and reversible to the original genetic state. Both population transformation and its reversal can be largely achieved within as few as 5 generations. The described genetic construct {Ud} is composed of two genes; (1) a UAS-RpL14.dsRNA targeting RNAi to a haploinsufficient gene RpL14 and (2) an RNAi insensitive RpL14 rescue. In this proof-of-principle system the UAS-RpL14.dsRNA knock-down gene is placed under the control of an Actin5c-GAL4 driver located on a different chromosome to the {Ud} insert. This configuration would not be effective in wild populations without incorporating the Actin5c-GAL4 driver as part of the {Ud} construct (or replacing the UAS promoter with an appropriate direct promoter). It is however anticipated that the approach that underlies this underdominant system could potentially be applied to a number of species.
Figure
Random-cluster representation of the Blume-Capel model
The so-called diluted-random-cluster model may be viewed as a random-cluster
representation of the Blume--Capel model. It has three parameters, a vertex
parameter , an edge parameter , and a cluster weighting factor .
Stochastic comparisons of measures are developed for the `vertex marginal' when
, and the `edge marginal' when q\in[1,\oo). Taken in conjunction
with arguments used earlier for the random-cluster model, these permit a
rigorous study of part of the phase diagram of the Blume--Capel model
Oncology Section EDGE Task Force on Cancer: Measures of Cancer-Related Fatigue—A Systematic Review
Background: Cancer-related fatigue (CRF) is one of the most common side effects of cancer and cancer treatment. Being able to accurately screen for and assess CRF will improve access to and prescriptions for interventions. Valid and reliable measures to screen for and assess CRF need to be identified.
Purpose: To identify and recommend reliable, valid, and clinically useful tools to screen for and assess CRF among those treated for cancer.
Methods: A systematic review of the literature was conducted to assess the published psychometric properties and clinical feasibility of each method identified. Task force members independently reviewed each measure using the Cancer EDGE Rating Form.
Results: Review of 136 studies resulted in recommendations for 14 questionnaires. Five unidimensional and 9 multidimensional questionnaires are recommended by the Oncology EDGE Task Force.
Conclusion: The 10-point Numeric Rating Scale for Fatigue is best as a screening tool, whereas the Multidimensional Fatigue Symptom Inventory is a highly recommended multidimensional tool. Ease of screening can promote referral for interventions, whereas thorough assessment drives appropriate interventions
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