10,214 research outputs found
Symbiotic stars in the Local Group of Galaxies
Preliminary results of the ongoing search for symbiotic binary stars in the
Local Group of Galaxies are presented and discussed.Comment: Proceedings of Physics of Evolved Stars 2015: A Conference Dedicated
to the Memory of Olivier Chesneau, Nice, 8-12 June 201
The luminosity function of Palomar 5 and its tidal tails
We present the main sequence luminosity function of the tidally disrupted
globular cluster Palomar 5 and its tidal tails. For this work we analyzed
imaging data obtained with the Wide Field Camera at the INT (La Palma) and data
from the Wide Field Imager at the MPG/ESO 2.2 m telescope at La Silla down to a
limiting magnitude of approximately 24.5 mag in B. Our results indicate that
preferentially fainter stars were removed from the cluster so that the LF of
the cluster's main body exhibits a significant degree of flattening compared to
other GCs. This is attributed to its advanced dynamical evolution. The LF of
the tails is, in turn, enhanced with faint, low-mass stars, which we interpret
as a consequence of mass segregation in the cluster.Comment: 4 pages, 3 figures, to be published in the proceedings of the
conference "Satellites and tidal streams" held at La Palma, Canary Islands,
May 26 - 30, 200
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Home accidents amongst elderly people: A locality study in Scotland
Aim
The aim of this locality study was to collect information on reported and unreported accidents amongst elderly people living in one locality in Scotland.
Method
Postal Survey- A postal questionnaire was sent to 3,757 men and women aged 65+ years living in one locality. The questionnaire asked respondents to indicate how many accidents they had experienced in the past twelve months, plus to indicate type and location. Information was gathered on living arrangements, ethnicity, gender, age and deprivation. Respondents were asked if they would be willing to take part in an interview study.
Interview Study - One hundred elders who had had at least one accident in the previous twelve months were interviewed.
Results
Postal Survey - Over a third of the respondents in the postal survey reported having had an accident in the previous twelve months. Bumps and drops and falls were the most common type of accident. Most accidents happened in the kitchen. Women reported more falls than men and those living alone reported more accidents than those living with others. Age was associated with the prevalence of accidents, but the association was somewhat curvilinear, with accidents decreasing with age and then increasing again.
Interview Study â Interviewees found it hard to differentiate one accident from another. Considerable reluctance to visit the GP after an accident was noted, with many not attending even for serious accidents. Almost forty percent were âveryâ distressed after their accident, and a quarter reported a loss of confidence. However, most did not worry about accidents. Few thought that their age, health or medications were a cause of their accidents
Formation of Black Holes from Collapsed Cosmic String Loops
The fraction of cosmic string loops which collapse to form black holes is
estimated using a set of realistic loops generated by loop fragmentation. The
smallest radius sphere into which each cosmic string loop may fit is obtained
by monitoring the loop through one period of oscillation. For a loop with
invariant length which contracts to within a sphere of radius , the
minimum mass-per-unit length necessary for the cosmic string
loop to form a black hole according to the hoop conjecture is . Analyzing loops, we obtain the empirical estimate for the fraction of cosmic string
loops which collapse to form black holes as a function of the mass-per-unit
length in the range . We
use this power law to extrapolate to , obtaining the
fraction of physically interesting cosmic string loops which
collapse to form black holes within one oscillation period of formation.
Comparing this fraction with the observational bounds on a population of
evaporating black holes, we obtain the limit on the cosmic string mass-per-unit-length. This limit is consistent
with all other observational bounds.Comment: uuencoded, compressed postscript; 20 pages including 7 figure
Substance Abuse via Legally Prescribed Drugs: The Case of Vicodin in the United States
Vicodin is the most commonly prescribed pain reliever in the United States.
Research indicates that there are two million people who are currently abusing
Vicodin, and the majority of those who abuse Vicodin were initially exposed to
it via prescription. Our goal is to determine the most effective strategies for
reducing the overall population of Vicodin abusers. More specifically, we focus
on whether prevention methods aimed at educating doctors and patients on the
potential for drug abuse or treatment methods implemented after a person abuses
Vicodin will have a greater overall impact. We consider one linear and two
non-linear compartmental models in which medical users of Vicodin can
transition into the abuser compartment or leave the population by no longer
taking the drug. Once Vicodin abusers, people can transition into a treatment
compartment, with the possibility of leaving the population through successful
completion of treatment or of relapsing and re-entering the abusive
compartment. The linear model assumes no social interaction, while both
non-linear models consider interaction. One considers interaction with abusers
affecting the relapse rate, while the other assumes both this and an additional
interaction between the number of abusers and the number of new prescriptions.
Sensitivity analyses are conducted varying the rates of success of these
intervention methods measured by the parameters to determine which strategy has
the greatest impact on controlling the population of Vicodin abusers. From
these models and analyses, we determine that manipulating parameters tied to
prevention measures has a greater impact on reducing the population of abusers
than manipulating parameters associated with treatment. We also note that
increasing the rate at which abusers seek treatment affects the population of
abusers more than the success rate of treatment itself
Preparation for cancer care: perceptions of newly qualified health care professionals
The present paper is derived from a larger survey which examined the perceptions of recently qualified health care professionalsâ experience on evidence-based practice, team working and cancer care. This study reports solely on the findings relating to cancer care. The perceptions of recently qualified professionals in relation to their initial educational input on issues such as confidence, anxiety, communication skills and practice in cancer care as well as adequacy of support, professional supervision and use of reflection were gathered using a cross-sectional postal survey design. A total of 50 graduates from each professional category in nursing, occupational therapy, physiotherapy, and social work were sampled yielding a total sample of 200. Eighty-five questionnaires were returned yielding a response rate of 43%. Twenty-eight (33%) respondents stated that they were currently involved in working with people with cancer. These were as follows: 5 nurses, 8 physiotherapists, 9 occupational therapists and 6 social workers. Despite the low response rate, the findings suggest that health care professionalsâ educational input and experiences of working with people with cancer were overall positive; for example, in the respondentsâ confidence, communication skills, decrease in anxiety and application of knowledge gained in classroom to professional practice. Moreover, most respondents learnt about caring for cancer patients through practice rather than classroom teaching. A high percentage (i.e. 64%;18) across all groups felt supported when caring for people with cancer and reported receiving professional supervision as well as being able to actively reflect on their practice. The implications for education and practice were discussed particularly as there have been few studies conducted in relation to the specific needs and collaborative learning of these health care professional groups
Cosmological milestones and energy conditions
Until recently, the physically relevant singularities occurring in FRW
cosmologies had traditionally been thought to be limited to the "big bang", and
possibly a "big crunch". However, over the last few years, the zoo of
cosmological singularities considered in the literature has become considerably
more extensive, with "big rips" and "sudden singularities" added to the mix, as
well as renewed interest in non-singular cosmological events such as "bounces"
and "turnarounds". In this talk, we present an extensive catalogue of such
cosmological milestones, both at the kinematical and dynamical level. First,
using generalized power series, purely kinematical definitions of these
cosmological events are provided in terms of the behaviour of the scale factor
a(t). The notion of a "scale-factor singularity" is defined, and its relation
to curvature singularities (polynomial and differential) is explored. Second,
dynamical information is extracted by using the Friedmann equations (without
assuming even the existence of any equation of state) to place constraints on
whether or not the classical energy conditions are satisfied at the
cosmological milestones. Since the classification is extremely general, and
modulo certain technical assumptions complete, the corresponding results are to
a high degree model-independent.Comment: 8 pages, 1 table, conference proceedings for NEB XII conference in
Nafplio, Greec
Metabolic responses of osteochondral allografts to re-warming after MOPS(TM) preservation versus standard of care storage
Osteoarthritis (OA) affects ~90% of people older than 65, and associated costs top $100 billion annually in the U.S. One treatment available for large cartilage defects seen in osteoarthritis is osteochondral allograft (OCA) transplantation. Currently, tissue banks store OCAs at 4 degree C and implantation is recommended within 28 days after procurement due to significant loss in chondrocyte viability after this time. Because mandatory disease screening protocols typically take 14 days to complete, the window for surgical implantation is narrow, which severely limits clinical use. The MOPS(TM) protocol can maintain OCAs for 56 days. In this study, OCAs stored using MOPS(TM) and SOC protocol were assessed for cell viability and metabolic biomarker production
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