386 research outputs found
Quantum equivalence of sigma models related by non Abelian Duality Transformations
Coupling constant renormalization is investigated in 2 dimensional sigma
models related by non Abelian duality transformations. In this respect it is
shown that in the one loop order of perturbation theory the duals of a one
parameter family of models, interpolating between the SU(2) principal model and
the O(3) sigma model, exhibit the same behaviour as the original models. For
the O(3) model also the two loop equivalence is investigated, and is found to
be broken just like in the already known example of the principal model.Comment: As a result of the collaboration of new authors the previously
overlooked gauge contribution is inserted into eq.(43) changing not so much
the formulae as part of the conclusion: for the models considered non Abelian
duality is OK in one loo
Порівняльна оцінка результатів хірургічного та консервативного лікування хворих з цукровим діабетом та хронічною критичною ішемією нижньої кінцівки
Мета. Порівняти результати консервативного лікування та ендоваскулярних і відкритих хірургічних втручань у хворих з цукровим діабетом та хронічною критичною ішемією нижньої кінцівки.
Матеріали і методи. Проаналізовано результати лікування 240 пацієнтів з цукровим діабетом (ЦД) 2-го типу та хронічною критичною ішемією нижньої кінцівки (ХКІНК), виразково-некротичним ураженням стопи на тлі стенотично - оклюзійного ураження артерій підколінно-гомілково-стопового сегмента. До групи А включили 143 (54,6%) пацієнти, яким було проведено хірургічне лікування, до групи Б – 97 (40,4%) пацієнтів, яких лікували консервативно. У свою чергу групу А розподілили на дві підгрупи: А1 – 42 (29,4%) пацієнти, яким виконали операцію шунтування до гомілкових або стопових артерій, та А2 - 101 (70,6%) пацієнт, якому виконали балонну ангіопластику. З метою коректного порівняння результатів різних видів лікування нами була розроблена методика розрахунку коефіцієнта рівня ампутації (КРА).
Результати. Із 42 хворих підгрупи А1 у 4 (9,5%) була виконана ампутація на рівні стегна, у 3 (7,1%) - на рівні гомілки, у 6 (14,3%) – трансметатарзальна резекція стопи, у 14 (33,3%) – ампутація пальців. У 15 (35,7%) хворих опорна функція стопи не порушилась. КРА у пацієнтів підгрупи А1 дорівнював 1,48. Із 101 хворого підгрупи А2 у 2 (2,0%) була виконана ампутація на рівні стегна, у 4 (4,0%) - на рівні гомілки, у 16 (15,8%) – трансметатарзальна резекція стопи, у 19 (18,8%) – ампутація пальців. У 60 (59,4%) хворих опорна функція стопи не порушилась. КРА у пацієнтів підгрупи А2 дорівнював 0,78. Із 97 хворих групи Б у 22 (22,7%) була виконана ампутація на рівні стегна, у 29 (29,9%) - на рівні гомілки, у 6 (6,2%) – трансметатарзальна резекція стопи, у 11 (11,3%) – ампутація пальців. У 29 (29,9%) хворих опорна функція стопи не порушилась. КРА у пацієнтів групи Б дорівнював 2,79.
Висновки. Розроблена методика розрахунку КРА може бути використана для порівняння результатів лікування хворих з ЦД та ХКІНК на тлі стенотично-оклюзійного ураження артерій підколінно-гомілково-стопового сегмента, у яких були застосовані різні методи лікування. Найкращі річні результати збереження опорної функції нижньої кінцівки спостерігали у хворих, яким виконали балонну ангіопластику, найгірші - у хворих, яким було проведено консервативне лікування
Normal families of functions and groups of pseudoconformal diffeomorphisms of quaternion and octonion variables
This paper is devoted to the specific class of pseudoconformal mappings of
quaternion and octonion variables. Normal families of functions are defined and
investigated. Four criteria of a family being normal are proven. Then groups of
pseudoconformal diffeomorphisms of quaternion and octonion manifolds are
investigated. It is proven, that they are finite dimensional Lie groups for
compact manifolds. Their examples are given. Many charactersitic features are
found in comparison with commutative geometry over or .Comment: 55 pages, 53 reference
Embolic stroke complicating Staphylococcus aureus endocarditis circumstantially linked to rectal trauma from foreign body: a first case report
BACKGROUND: Diagnostic and therapeutic instrumentation of the lower gastrointestinal tract has been reported to result in bacteremia and endocarditis. No such case has been reported in persons with a history of rectal foreign body insertion despite its potential for greater trauma. CASE PRESENTATION: A 58-year-old male was admitted with confusion and inability to speak. His past history was notable for hospitalization to extract a retained plastic soda bottle from the rectosigmoid two years prior. On examination, he was febrile, tachycardic and hypotensive. There was an apical pansystolic murmur on cardiac examination. He had a mixed receptive and expressive aphasia, and a right hemiparesis. On rectal examination he had perianal erythema and diminished sphincter tone. Magnetic resonance imaging of the brain showed infarction of the occipital and frontal lobes. Transesophageal Echocardiography of the heart revealed vegetations on the mitral valve. All of his blood culture bottles grew methicillin sensitive Staphylococcus aureus. He was successfully treated for bacterial endocarditis with intravenous nafcillin and gentamicin. The rectum is frequently colonized by Staphylococcus aureus and trauma to its mucosa can lead to bacteremia and endocarditis with this organism. In the absence of corroborative evidence such as presented here, it is difficult to make a correlation between staphylococcal endocarditis and anorectal foreign body insertion due to patients being less than forthcoming CONCLUSION: There is a potential risk of staphylococcal bacteremia and endocarditis with rectal foreign body insertion. Further studies are needed to explore this finding. Detailed sexual history and patient counseling should be made a part of routine primary care
Quality of colonoscopy in an emerging country: A prospective, multicentre study in Russia
Background: The quality of colonoscopy has been related to a higher risk of interval cancer, and this issue has been addressed extensively in developed countries. The aim of our study was to explore the main quality indicators of colonoscopy in a large emerging country. Methods: Consecutive patients referred for colonoscopy in 14 centres were prospectively included between July and October 2014. Before colonoscopy, several clinical and demographic variables were collected. Main quality indicators (i.e. caecal intubation rate, (advanced) adenoma detection rate, rate of adequate cleansing and sedation) were collected. Data were analysed at per patient and per centre level (only for those with at least 100 cases). Factors associated with caecal intubation rate and adenoma detection rate were explored at multivariate analysis. Results: A total of 8829 (males: 35%; mean age: 57 + 14 years) patients were included, with 11 centres enrolling at least 100 patients. Screening (including non-alarm symptoms) accounted for 59% (5188/8829) of the indications. Sedation and split preparation were used in 26% (2294/8829) and 25% (2187/8829) of the patients. Caecal intubation was achieved in 7616 patients (86%), and it was ≥85% in 8/11 (73%) centres. Adenoma detection rate was 18% (1550/8829), and it was higher than 20% in five (45%) centres, whilst it was lower than 10% in four (33%) centres. At multivariate analysis, age (OR: 1.020, 95% CI: 1.015–1.024), male sex (OR: 1.2, 95% CI: 1.1–1.3), alarm symptoms (OR: 1.8, 95% CI: 1.7–2), split preparation (OR: 1.4, 95% CI: 1.2–1.6), caecal intubation rate (OR: 1.6, 95% CI: 1.3–1.9) and withdrawal time measurement (OR: 1.2, 95% CI: 1.6–2.1) were predictors of a higher adenoma detection rate, while adequate preparation (OR: 3.4: 95% CI: 2.9–3.9) and sedation (OR: 1.3; 95% CI: 1.1–1.6) were the strongest predictors of caecal intubation rate. Conclusions: According to our study, there is a substantial intercentre variability in the main quality indicators. Overall, the caecal intubation rate appears to be acceptable in most centres, whilst the overall level of adenoma detection appears low, with less than half of the centres being higher than 20%. Educational and quality assurance programs, including higher rates of sedation and split regimen of preparation, may be necessary to increase the key quality indicators
New limits on the resonant absorption of solar axions obtained with a Tm-containing cryogenic detector
A search for resonant absorption of solar axions by Tm nuclei was
carried out. A newly developed approach involving low-background cryogenic
bolometer based on TmAlO crystal was used that allowed for
significant improvement of sensitivity in comparison with previous Tm
based experiments. The measurements performed with g crystal during
days exposure yielded the following limits on axion couplings:
GeV and
.Comment: 7 pages, 5 figure
Comparing electron precipitation fluxes calculated from pitch angle diffusion coefficients to LEO satellite observations
Particle precipitation is a loss mechanism from the Radiation Belts whereby particles trapped by the Earth’s magnetic field are scattered into the loss cone due to wave‐particle interactions. Energetic electron precipitation creates ozone destroying chemicals which can affect the temperatures of the polar regions, therefore it is crucial to accurately quantify this impact on the Earth’s atmosphere. We use bounce‐averaged pitch angle diffusion coefficients for whistler mode chorus waves, plasmaspheric hiss and atmospheric collisions to calculate magnetic local time (MLT) dependent electron precipitation inside the field of view of the Polar Orbiting Environmental Satellites (POES) T0 detector, between 26‐30 March 2013. These diffusion coefficients are used in the BAS Radiation Belt Model (BAS‐RBM) and this paper is a first step towards testing the loss in this model via comparison with real world data. We find the best agreement between the calculated and measured T0 precipitation at L* > 5 on the dawnside for the > 30keV electron channel, consistent with precipitation driven by lower band chorus. Additional diffusion is required to explain the flux at higher energies and on the dusk side. The POES T0 detector underestimates electron precipitation as its field of view does not measure the entire loss cone. We demonstrate the potential for utilizing diffusion coefficients to reconstruct precipitating flux over the entire loss cone. Our results show that the total precipitation can exceed that measured by the POES > 30 keV electron channel by a factor that typically varies from 1 to 10 for L* = 6, 6.5 and 7
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