11,753 research outputs found
A dilogarithmic integral arising in quantum field theory
Recently, an interesting dilogarithmic integral arising in quantum field
theory has been closed-form evaluated in terms of the Clausen function
by Coffey [J. Math. Phys.} 49 (2008), 093508]. It
represents the volume of an ideal tetrahedron in hyperbolic space and is
involved in two intriguing equivalent conjectures of Borwein and Broadhurst. It
is shown here, by simple and direct arguments, that this integral can be
expressed by the triplet of the Clausen function values which are involved in
one of the two above-mentioned conjectures.Comment: 6 page
Prochloron research
The purpose was to prepare Prochloron photosynthetic membranes for the isolation of the two major chlorophyll-proteins, the P700-chlorophyll a-protein and the light-harvesting chlorophyll a/b-protein, using SDS-polyacrylamide gel electrophoresis. The prepared proteins (purified) were examined for their cross-reactivity to polyclonal antibodies prepared from higher plant proteins. In addition, material was prepared for electron microscopy, and isolation of the DNA for determination of its general complexity (COT analysis) and similarity to barley chloroplast DNA and Anabaena DNA by using restriction-endonuclease analysis. Kleinschmidt spreads of the DNA were in the electron microscope to identify and measure the extent and size of the circlar DNA
Scalar Field Theory at Finite Temperature in D=2+1
We discuss the theory defined in -dimensional space-time and
assume that the system is in equilibrium with a thermal bath at temperature
. We use the expansion and the method of the composite
operator (CJT) for summing a large set of Feynman graphs.We demonstrate
explicitly the Coleman-Mermin-Wagner theorem at finite temperature.Comment: 12 pages, 1 figure. To be published in Journal Mathematical Physics,
typos adde
The views of young people with congenital cardiac disease on designing the services for their treatment
Background and purpose: There is little documented evidence of young people with congenital cardiac disease being consulted as to what help, if any, they really need in relation to their condition. Most research concentrates on the medical aspects of the condition. There are studies of psychological and social functioning, but few have directly sought the opinions of the young people. More recent research has indicated a need for health professionals to develop services to meet both psychosocial and physical needs of young people with congenital cardiac disease. The findings of the recent Kennedy Report support this need. The purpose of this study was to explore the views of young people with a range of congenital cardiac conditions, on what would help them better deal with their condition, and when and how help might be provided. Methods: This was a qualitative study using semi-structured interviews. We interviewed 16 young people in their own home. Interviews were tape-recorded and transcribed. Analysis was conducted using the "Framework" method. Results: Whilst most of the young people interviewed actively manage their condition, they think more support from others would be beneficial. Issues of activity and communication were cited most often as areas requiring more understanding from people they interact with, for example teachers and peers. The discussion focuses on how health professionals might change or develop their practice to help young people better cope with their condition. Conclusions: Most of the young people interviewed in this study had developed their own strategies for coping with their condition. Although this is a small study, the young people provided important suggestions as to how health professionals could better develop current services
A simple screening method for determining knowledge of the appropriate levels of activity and risk behaviour in young people with congenital cardiac conditions
Objective: To assess a novel method for assessing risk and providing advice about activity to children and young people with congenital cardiac disease and their parents. Design and setting: Questionnaire survey in outpatient clinics at a tertiary centre dealing with congenital cardiac disease, and 6 peripheral clinics. Interventions: Children or their parents completed a brief questionnaire. If this indicated a desire for help, or a serious mismatch between advised and real level of activity, they were telephoned by a physiotherapist. Main measures of outcome: Knowledge about appropriate levels of activity, and identification of the number exercising at an unsafe level, the number seeking help, and the type of help required. Results: 253/258 (98.0%) questionnaires were returned, with 119/253 (47.0%) showing incorrect responses in their belief about their advised level of exercise; 17/253 (6.7%) had potentially dangerous overestimation of exercise. Asked if they wanted advice 93/253 (36.8%) said “yes”, 43/253 (17.0%) “maybe”, and 117/253 (46.2%) “no”. Of those contacted by phone to give advice, 72.7% (56/77) required a single contact and 14.3% (11/77) required an intervention that required more intensive contact lasting from 2 up to 12 weeks. Of the cohort, 3.9% (3/77) were taking part in activities that put them at significant risk. Conclusions: There is a significant lack of knowledge about appropriate levels of activity, and a desire for further advice, in children and young people with congenital cardiac disease. A few children may be at very significant risk. These needs can be identified, and clinical risk reduced, using a brief self-completed questionnaire combined with telephone follow-up from a suitably knowledgeable physiotherapist
The end of HIV: Still a very long way to go, but progress continues.
In an Editorial accompanying PLOS Medicine's Special Issue on Advances in Prevention, Treatment and Cure of HIV/AIDS, Guest Editors Steven Deeks, Sharon Lewin, and Linda-Gail Bekker discuss priorities in the field and the content of the issue
Adherence to cardiac rehabilitation guidelines: a survey of rehabilitation programmes in the United Kingdom
Two key recommendations of recent guidelines are that cardiac rehabilitation requires the skills of a range of professionals and that the patient should receive a menu based programme after an individual assess ment of needs. A previous survey of 25 cardiac rehabilitation programmes found little congruence with these guidelines and noted that physicians were particularly unlikely to be involved. We extended this inquiry to include all of the discoverable rehabilitation programmes in the United Kingdom
Environment Agency review of methods for determining organic waste biodegradability and municipal waste diversion.
The Environment Agency is required to regulate
the landfilling of biodegradable organic wastes
and their diversion from landfilling. Simple, cost
effective, reliable and widely applicable methods
for the measurement of organic waste and its
biodegradability are needed for this activity. A
review of such methods was carried out in order to
select promising methods for an experimental
screening exercise. The review considered both
biological and non-biological methods including
simple methods that may provide a surrogate
measurement of waste biodegradability instead of
the time-consuming biological methods. The
biological methods selected for further evaluation
were the aerobic specific oxygen uptake rate
(SOUR) and dynamic respiration index (DRI)
tests, and the anaerobic biochemical methane
potential (BMP) test.
The non-biological methods selected for further
evaluation were dry matter (DM), loss on ignition
(LOI), total organic carbon (TOC), total nitrogen
(TN), water extractable dissolved organic carbon
(DOC), BOD and COD, the lignin and cellulose
content and the cellulase hydrolysis method.
These tests are being evaluated on a wide variety
of typical organic materials that might be found in
municipal solid waste (MSW) such as newspaper
corrugated paper, compost, kitchen waste
(vegetable and animal), garden wastes (grass and
twigs), nappies, cotton and wool textiles
Evaluation of a ln tan integral arising in quantum field theory
We analytically evaluate a dilogarithmic integral that is prototypical of
volumes of ideal tetrahedra in hyperbolic geometry. We additionally obtain new
representations of the Clausen function Cl_2 and the Catalan constant
G=Cl_2(\pi/2), as well as new relations between sine and Clausen function
values.Comment: 24 pages, no figure
An orientable, stabilized balloon-borne gondola for around-the-world flights
A system capable of pointing a balloon-borne telescope at selected celestial objects to an accuracy of approximately 10 arc minutes for an extended period (weeks to months) without reliance on telemetry is described. A unique combination of a sun/star tracker, an on-board computer, and a gyrocompass is utilized for navigation, source acquisition and tracking, and data compression and recording. The possibilities for intelligent activities by the computer are also discussed
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