447 research outputs found
Reversible adsorption on a random site surface
We examine the reversible adsorption of hard spheres on a random site surface
in which the adsorption sites are uniformly and randomly distributed on a
plane. Each site can be occupied by one solute provided that the nearest
occupied site is at least one diameter away. We use a numerical method to
obtain the adsorption isotherm, i.e. the number of adsorbed particles as a
function of the bulk activity. The maximum coverage is obtained in the limit of
infinite activity and is known exactly in the limits of low and high site
density. An approximate theory for the adsorption isotherms, valid at low site
density, is developed by using a cluster expansion of the grand canonical
partition function. This requires as input the number of clusters of adsorption
site of a given size. The theory is accurate for the entire range of activity
as long as the site density is less than about 0.3 sites per particle area. We
also discuss a connection between this model and the vertex cover problem.Comment: 16 pages, 10 figure
The Isolation of an Actinomycetes-Like Organism from Root Canals
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/67354/2/10.1177_00220345410200030301.pd
Evaluation of a multidisciplinary Tier 3 weight management service for adults with morbid obesity, or obesity and comorbidities, based in primary care
A multidisciplinary Tier 3 weight management service in primary care recruited patients with a body mass index âĽ40âkg¡mâ2, or 30âkg¡mâ2 with obesity-related co-morbidity to a 1-year programme. A cohort of 230 participants was recruited and evaluated using the National Obesity Observatory Standard Evaluation Framework. The primary outcome was weight loss of at least 5% of baseline weight at 12 months. Diet was assessed using the two-item food frequency questionnaire, activity using the General Practice Physical Activity questionnaire and quality of life using the EuroQol-5D-5L questionnaire. A focus group explored the participants' experiences. Baseline mean weight was 124.4âkg and mean body mass index was 44.1âkg¡mâ2. A total of 102 participants achieved 5% weight loss at 12 months. The mean weight loss was 10.2âkg among the 117 participants who completed the 12-month programme. Baseline observation carried forward analysis gave a mean weight loss of 5.9âkg at 12 months. Fruit and vegetable intake, activity level and quality of life all improved. The dropout rate was 14.3% at 6 months and 45.1% at 1 year. Focus group participants described high levels of satisfaction. It was possible to deliver a Tier 3 weight management service for obese patients with complex co-morbidity in a primary care setting with a full multidisciplinary team, which obtained good health outcomes compared with existing services
Discovery of a Second Nova Eruption of V2487 Ophiuchi
A directed search for previously-undiscovered nova eruptions was conducted in
the astronomical plate archives at Harvard College Observatory and Sonneberg
Observatory. We found that an eruption of V2487 Oph (Nova Oph 1998) occurred on
1900 June 20. V2487 Oph was previously classified as a classical nova, which we
identified as a probable recurrent nova based on its large expansion velocities
and the presence of high excitation lines in the outburst spectrum. The event
was recorded on Harvard plate AM 505, at a B magnitude of 10.27 +/- 0.11, which
is near peak. The outburst can only be seen on one plate, but the image has a
characteristic dumbbell shape (caused by a double exposure) that is identical
to the other star images on the plate, and thus is not a plate defect. We
conclude that this is in fact a previously-undiscovered nova outburst of V2487
Oph, confirming our prediction that it is a recurrent nova. We also examine the
discovery efficiency for eruptions of the system and conclude that a
randomly-timed outburst has, on average, a 30% chance of being discovered in
the past century. Using this, we deduce a recurrence time for V2487 Oph of
approximately 18 years, which implies that the next eruption is expected around
2016.Comment: 18 pages, 2 figures, to be published in the Astronomical Journa
Transient, unsettling and creative space: Experiences of liminality through the accounts of Chinese students on a UK-based MBA
This is the author's accepted manuscript. The final published article is available from the link below. Copyright @ The Author(s) 2009.This article explores the experiences of liminality through the accounts of Chinese students on a UK-based MBA programme. The transient nature of the MBA experience, as well as the international status of the Chinese student, is resonant with conceptualizations of liminality as âin betweenâ space. Based on semi-structured interviews with 20 MBA graduates who had subsequently returned to China with their qualification, we explored their perceptions of outcomes from the course and their experiences as international students on a programme imbued with western norms and values. Results support the unsettling yet creative implications of liminality, as well as the fragmented insecure nature of identities, as individuals pass through the MBA ârite of passageâ in terms of âbecomingâ a manager and entering a new phase of career. Accounts suggest the creation of hierarchical structures within liminal space whereby Chinese students, through their positioning at the margin, have uncomfortable yet illuminating encounters with alterity. At the same time, they experience levels of ambiguity and uncertainty in the post-liminal phase of China-located employments, as new western-based managerial identities collide with dominant discourses of Chinese organization
Comparison of Robotic vs Open Cystectomy: A Systematic Review.
BACKGROUND
The benefits of a robot-assisted radical cystectomy (RARC) compared to an open approach is still under debate. Initial data on RARC were from trials where urinary diversion was performed by an extracorporeal approach, which does not represent a completely minimally invasive procedure. There are now updated data for RARC with intracorporeal urinary diversion that add to the evidence profile of RARC.
OBJECTIVE
To perform a systematic review and meta-analysis of the effectiveness of RARC compared with open radical cystectomy (ORC).
MATERIALS AND METHODS
Multiple databases were searched up to May 2022. We included randomised trials in which patients underwent RARC and ORC. Oncological and safety outcomes were assessed.
RESULTS
Seven trials of 907 participants were included. There were no differences seen in primary outcomes: disease progression [RR 0.98, 95% CI 0.78 to 1.23], major complications [RR 0.95, 95% CI 0.72 to 1.24] and quality of life [SMD 0.05, 95% CI -0.13 to 0.38]. RARC resulted in a decreased risk of perioperative blood transfusion [RR 0.57, 95% CI 0.43 to 0.76], wound complications [RR 0.34, 95% CI 0.21 to 0.55] and reduced length of hospital stay [MD -0.62 days, 95% CI -1.11 to -0.13]. However, there was an increased risk of developing a ureteric stricture [RR 4.21, 95% CI 1.07 to 16.53] in the RARC group and a prolonged operative time [MD 70.4 minutes, 95% CI 34.1 to 106.7]. The approach for urinary diversion did not impact outcomes.
CONCLUSION
RARC is an oncologically safe procedure compared to ORC and provides the benefits of a minimally invasive approach. There was an increased risk of developing a ureteric stricture in patients undergoing RARC that warrants further investigation. There was no difference in oncological outcomes between approaches
An exploratory cluster randomised controlled trial of knowledge translation strategies to support evidence-informed decision-making in local governments (The KT4LG study)
Background: Childhood overweight and obesity is the most prevalent and, arguably, politically complex child health problem internationally. Governments, communities and industry have important roles to play, and are increasingly expected to deliver an evidence-informed system-wide prevention program. However, efforts are impeded by a lack of organisational access to and use of research evidence. This study aims to identify feasible, acceptable and ideally, effective knowledge translation (KT) strategies to increase evidence-informed decision making in local governments, within the context of childhood obesity prevention as a national policy priority.Methods/Design: This paper describes the methods for KT4LG, a cluster randomised controlled trial which is exploratory in nature, given the limited evidence base and methodological advances. KT4LG aims to examine a program of KT strategies to increase the use of research evidence in informing public health decisions in local governments. KT4LG will also assess the feasibility and acceptability of the intervention. The intervention program comprises a facilitated program of evidence awareness, access to tailored research evidence, critical appraisal skills development, networking and evidence summaries and will be compared to provision of evidence summaries alone in the control program. 28 local governments were randomised to intervention or control, using computer generated numbers, stratified by budget tertile (high, medium or low). Questionnaires will be used to measure impact, costs, and outcomes, and key informant interviews will be used to examine processes, feasibility, and experiences. Policy tracer studies will be included to examine impact of intervention on policies within relevant government policy documents.Discussion: Knowledge translation intervention studies with a focus on public health and prevention are very few in number. Thus, this study will provide essential data on the experience of program implementation and evaluation of a system-integrated intervention program employed within the local government public health context. Standardised programs of system, organisational and individual KT strategies have not been described or rigorously evaluated. As such, the findings will make a significant contribution to understanding whether a facilitated program of KT strategies hold promise for facilitating evidence-informed public health decision making within complex multisectoral government organisations.<br /
Infrared Properties of Cataclysmic Variables from 2MASS: Results from the 2nd Incremental Data Release
Because accretion-generated luminosity dominates the radiated energy of most
cataclysmic variables, they have been ``traditionally'' observed primarily at
short wavelengths. Infrared observations of cataclysmic variables contribute to
the understanding of key system components that are expected to radiate at
these wavelengths, such as the cool outer disk, accretion stream, and secondary
star. We have compiled the J, H, and Ks photometry of all cataclysmic variables
located in the sky coverage of the 2 Micron All Sky Survey (2MASS) 2nd
Incremental Data Release. This data comprises 251 systems with reliably
identified near-IR counterparts and S/N > 10 photometry in one or more of the
three near-IR bands.Comment: 2 pages, including 1 figure. To appear in the proceedings of The
Physics of Cataclysmic Variables and Related Objects, Goettingen, Germany.
For our followup ApJ paper (in press), also see
http://www.ctio.noao.edu/~hoard/research/2mass/index.htm
- âŚ