Response of conifers to UV-B and climate in mountain areas

The present study was focused to examine the combined effects of climate and ultraviolet-B radiation on conifer tree-ring density. Statistical methods were employed to extract tree responses in annual ring density and to identify functional relationship in trees when the level of ultraviolet-B radiation changes regardless of climate variations. In this study, the consideration was given to the series of total ozone content (instead of ultraviolet-B), tree-ring density, and De Martonne aridity index. After the correlation analysis, all trees were divided into two groups: 1) Trees whose correlation between tree ring density and UV-B values in April is significantly positive; 2) Trees whose correlation between tree ring density and aridity index values in March-September is significantly negative. Then, tree-ring series for the Swiss Alps in each group were generalized and decomposed into separate components: long period trends, ultraviolet-B and climatic signals. For the ultraviolet-B-responsive tree group in the period 1932-1974, the correlation coefficient between the density and ultraviolet-B was 0.55 at

Разработка экспериментальной модели вульгарной пузырчатки на лабораторных животных

Pemphigus vulgaris is a chronic autoimmune bullous disease characterized by the formation of blisters on the skin and/ or mucous tunics as a result of acantholysis. To search for new molecular and biological targets, study pathogenetic mechanisms of the disease development and develop new methods of treatment, it is urgent to create an experimental model of pemphigus in laboratory animals reproducing clinical, histological and immunological signs of pemphigus. Goal of the study. To develop an experimental model of pemphigus by injecting IgG produced from the blood serum taken from patients with pemphigus to neonatal mice of the BALB/c inbred line. Results. Accumulated IgG products taken from patients with pemphigus (main groups) and healthy volunteers (control group) were injected intraperitoneally to neonatal mice of the BALB/с in the doses of 10-30 mg per mouse. Clinical, histological and immunomorphological signs of pemphigus were revealed in the mice from the main group, which received intraperitoneal injections of IgG taken from patients with pemphigus in the dose of 30 mg per mouse. No signs of pemphigus were observed in the mice from the control group, which received injections of IgG taken from healthy people. This study confirms the role of pemphigus autoantibodies in the pathogenesis of pemphigus vulgaris and shows that passive transmission of antibodies to laboratory animals is possible.Вульгарная пузырчатка - хроническое аутоиммунное буллезное заболевание, характеризующееся образованием пузырей на коже и/или слизистых оболочках вследствие акантолиза. Для поиска новых молекулярно-биологических мишеней, изучения патогенетических механизмов развития заболевания, разработки новых методов терапии представляется актуальным создание экспериментальной модели пузырчатки на лабораторных животных, воспроизводящей клинические, гистологические и иммунологические признаки пузырчатки. Цель исследования. Разработка экспериментальной модели пузырчатки путем введения неонатальным мышам инбредной линии BALB/c препаратов IgG, полученных из сыворотки крови больных пузырчаткой. Результаты. Новорожденным мышам линии BALB/с внутрибрюшинно введены препараты суммарных IgG, полученные от больных пузырчаткой (основная группа) и здоровых добровольцев (контрольная группа), в дозах от 10 до 30 мг/мышь. У мышей основной группы, получавших внутрибрюшинные инъекции IgG от больных пузырчаткой в дозе 30 мг/мышь, определены клинические, гистологические и иммуноморфологические признаки пузырчатки. У мышей контрольной группы, которым вводились препараты IgG здоровых лиц, признаки пузырчатки не наблюдались. Данное исследование подтверждает роль пемфигусных аутоантител в патогенезе вульгарной пузырчатки и показывает возможность пассивной передачи антител лабораторным животным

RF photogun and Cherenkov decelerating system for a high power radiation source in sub-mm region

Some results of RF photogun and Cherenkov decelerating system research and design are discussed. This R&D is providing to construct a high power pulse radiation source in sub-mm region. It is well known that the conducting capillary filled by dielectric skin can be used as a Cherenkov radiation generator. One needs very short (less than 1 mm) and high brightness electron bunch to provide the coherent radiation. The short bunch can be generated by means of a photogun. The electrons should be accelerated to the energy equal to 1…4 MeV in compact section and injected to the decelerating structure. This radiation source can be used for inspection systems or as a laboratory generator.Рассмотрены некоторые результаты исследования и разработки СВЧ-фотокатода и черенковской замедляющей системы, предназначенных для генерации мощных импульсов излучения субмиллиметрового диапазона. Как известно, проводящий капилляр, покрытый изнутри слоем диэлектрика, может быть использован в качестве источника черенковского излучения. Для получения монохроматического излучения необходимо иметь очень короткий (меньше 1 мм) сгусток электронов, который может быть получен при использовании фотокатода. Электроны должны быть ускорены в короткой системе до энергии 1…4 МэВ и инжектированы в замедляющую систему. Такой источник излучения может быть использован в досмотровой системе или в качестве лабораторного генератора.Розглянуто деякі результати дослідження та розробки НВЧ-фотокатода і черенківської уповільнюючої системи, призначених для генерації потужних імпульсів випромінювання субміліметрового діапазону. Як відомо, проводячий капіляр, покритий зсередини шаром діелектрика, може бути використаний як джерело черенківського випромінювання. Для отримання монохроматичного випромінювання необхідно мати дуже короткий (менше 1 мм) згусток електронів, який може бути отриманий при використанні фотокатода. Електрони мають бути прискорені в короткій системі до енергії 1…4 МеВ і інжектовані в уповільнюючу систему. Таке джерело випромінювання може бути використано в оглядовій системі або в якості лабораторного генератора

The problem of plasma density increasing in the U-3M torsatron after RF heating termination

In the U-3M torsatron a significant chord-averaged plasma density increase is observed after the RF-heating termination. The objective of this work is to find out possible mechanisms resulting in plasma density increasing.В торсатроне У-3М можно увидеть значительное увеличение средней плотности плазмы после прекращения ВЧ-нагрева. Целью данной работы является выяснение механизмов, приводящих к такому увеличению.У торсатроні У-3М можна побачити значне збільшення середньої густини плазми після припинення ВЧ-нагрівання. Метою даної роботи є з'ясування механізмів, що призводять до такого збільшення

Measurement of the polarisation of W bosons produced with large transverse momentum in pp collisions at sqrt(s) = 7 TeV with the ATLAS experiment

This paper describes an analysis of the angular distribution of W->enu and W->munu decays, using data from pp collisions at sqrt(s) = 7 TeV recorded with the ATLAS detector at the LHC in 2010, corresponding to an integrated luminosity of about 35 pb^-1. Using the decay lepton transverse momentum and the missing transverse energy, the W decay angular distribution projected onto the transverse plane is obtained and analysed in terms of helicity fractions f0, fL and fR over two ranges of W transverse momentum (ptw): 35 < ptw < 50 GeV and ptw > 50 GeV. Good agreement is found with theoretical predictions. For ptw > 50 GeV, the values of f0 and fL-fR, averaged over charge and lepton flavour, are measured to be : f0 = 0.127 +/- 0.030 +/- 0.108 and fL-fR = 0.252 +/- 0.017 +/- 0.030, where the first uncertainties are statistical, and the second include all systematic effects.Comment: 19 pages plus author list (34 pages total), 9 figures, 11 tables, revised author list, matches European Journal of Physics C versio

Observation of a new chi_b state in radiative transitions to Upsilon(1S) and Upsilon(2S) at ATLAS

The chi_b(nP) quarkonium states are produced in proton-proton collisions at the Large Hadron Collider (LHC) at sqrt(s) = 7 TeV and recorded by the ATLAS detector. Using a data sample corresponding to an integrated luminosity of 4.4 fb^-1, these states are reconstructed through their radiative decays to Upsilon(1S,2S) with Upsilon->mu+mu-. In addition to the mass peaks corresponding to the decay modes chi_b(1P,2P)->Upsilon(1S)gamma, a new structure centered at a mass of 10.530+/-0.005 (stat.)+/-0.009 (syst.) GeV is also observed, in both the Upsilon(1S)gamma and Upsilon(2S)gamma decay modes. This is interpreted as the chi_b(3P) system.Comment: 5 pages plus author list (18 pages total), 2 figures, 1 table, corrected author list, matches final version in Physical Review Letter

Search for displaced vertices arising from decays of new heavy particles in 7 TeV pp collisions at ATLAS

We present the results of a search for new, heavy particles that decay at a significant distance from their production point into a final state containing charged hadrons in association with a high-momentum muon. The search is conducted in a pp-collision data sample with a center-of-mass energy of 7 TeV and an integrated luminosity of 33 pb^-1 collected in 2010 by the ATLAS detector operating at the Large Hadron Collider. Production of such particles is expected in various scenarios of physics beyond the standard model. We observe no signal and place limits on the production cross-section of supersymmetric particles in an R-parity-violating scenario as a function of the neutralino lifetime. Limits are presented for different squark and neutralino masses, enabling extension of the limits to a variety of other models.Comment: 8 pages plus author list (20 pages total), 8 figures, 1 table, final version to appear in Physics Letters

Measurement of the inclusive isolated prompt photon cross-section in pp collisions at sqrt(s)= 7 TeV using 35 pb-1 of ATLAS data

A measurement of the differential cross-section for the inclusive production of isolated prompt photons in pp collisions at a center-of-mass energy sqrt(s) = 7 TeV is presented. The measurement covers the pseudorapidity ranges |eta|<1.37 and 1.52<=|eta|<2.37 in the transverse energy range 45<=E_T<400GeV. The results are based on an integrated luminosity of 35 pb-1, collected with the ATLAS detector at the LHC. The yields of the signal photons are measured using a data-driven technique, based on the observed distribution of the hadronic energy in a narrow cone around the photon candidate and the photon selection criteria. The results are compared with next-to-leading order perturbative QCD calculations and found to be in good agreement over four orders of magnitude in cross-section.Comment: 7 pages plus author list (18 pages total), 2 figures, 4 tables, final version published in Physics Letters