МУЛЬТИЦЕНТРОВОЙ АНАЛИЗ РЕЗУЛЬТАТОВ ПРИМЕНЕНИЯ ПРЯМОГО БОКОВОГО МЕЖТЕЛОВОГО СПОНДИЛОДЕЗА (DLIF) И ТРАНСКУТАННОЙ ТРАНСПЕДИКУЛЯРНОЙ ФИКСАЦИИ У ПАЦИЕНТОВ С ДЕГЕНЕРАТИВНЫМИ ЗАБОЛЕВАНИЯМИ МЕЖПОЗВОНКОВЫХ ДИСКОВ ПОЯСНИЧНОГО ОТДЕЛА ПОЗВОНОЧНИКА

Background: The technique of lateral lumbar interbody fusion for the surgical treatment of patients with degenerative diseases of the lumbar spine was developed in the early 2000s. But at the same time in modern literature there is no uniform approach to the use this technique, clinical outcomes and radiological findings are contradictory. Aims: to conduct a multicenter analysis of clinical outcomes and instrumental data of direct lateral interbody fusion (DLIF) approach combined with transcutaneous pedicle fixation in patients with single-level degenerative disc diseases of the lumbar spine. Materials and methods: The study included 103 patients (63 men and 40 women, mean age 45.8±9.7 years) who underwent surgery followed by DLIF transcutaneous pedicle fixation. The surgery was performed at neurosurgical and vertebrological departments in Irkutsk (Russia), Omsk (Russia), and Astana (Kazakhstan). Dynamic observation and comprehensive clinical and instrumental evaluation of the treatment results were carried out for an 18-month period after surgery. Results: After the simultaneous decompressive-stabilizing intervention, in all patients we detected a decrease in the severity of pain syndrome on VAS — from 6.9±1.6 to 1.7±1.2 cm (p0.001), and improved quality of life index (Oswestry) — from 21.3±6.8 to 12.3±4.4% (p0.001). The instrumental methods of examination determined the effective indirect decompression: an increase in the size of interbody gap in the middle of its department compared with the preoperative value from 8.6±3.1 to 15.7±4.2 mm (p0.001) and an increase in the area of the intervertebral foramen (on the left with an average of 98.7±32.3 and 156.8±45.1 mm2, p0.001; on the right —99.7±37.3 to 153.4±38.7 mm2, p0.001). We also registered the restoration of both the segmental (from 10.2±3.8 to 13.6±6.7°, p0.001) and regional (from 32.8±5.9 to 48.2±7.3°, р0.001) lumbar lordosis. Complete interbody fusion was diagnosed in 87 (86.4%) patients. Complications were observed in 8.7% of cases. Conclusions: DLIF technique combined with transcutaneous transpedicular stabilization has high clinical efficacy confirmed by significant reduction in the severity of pain according to VAS. The studied approach improves the quality of life of patients by Oswestry index and reveals a low number of postoperative complications. The described simultaneous minimally invasive method of surgical treatment in patients with degenerative disc diseases allows to restore the sagittal profile of the lumbar spine and implement an effective stabilization of the operated vertebral-motor segments with a high degree of formation of interbody bone block.Обоснование. Методика бокового поясничного межтелового спондилодеза для хирургического лечения пациентов с дегенеративными заболеваниями поясничного отдела позвоночника разработана в начале 2000-х годов. Но при этом в современных литературных источниках отсутствует единый подход к ее использованию, а клинические исходы и рентгенологические результаты являются противоречивыми.Цель исследования: провести мультицентровой анализ клинических исходов и инструментальных данных использования методики прямого бокового межтелового спондилодеза (Direct lateral interbody fusion, DLIF) в сочетании с транскутанной транспедикулярной фиксацией у пациентов с одноуровневыми дегенеративными заболеваниями межпозвонковых дисков поясничного отдела позвоночника.Методы. В исследование включены 103 пациента (63 мужчины, 40 женщин, средний возраст 45,8±9,7 года), оперированных в нейрохирургических и вертебрологических отделениях Иркутска (Россия), Омска (Россия), Астаны (Казахстан), которым была выполнена операция DLIF с последующей транскутанной транспедикулярной стабилизацией. Динамическое наблюдение и комплексную клиническую и инструментальную оценку результатов лечения проводили в течение 18 мес после операции.Результаты. После симультанного декомпрессивно-стабилизирующего вмешательства у всех пациентов отмечено уменьшение степени выраженности болевого синдрома по визуальной аналоговой шкале (ВАШ) с 6,9±1,6 до 1,7±1,2 см (p0,001) и улучшение качества жизни по индексу Освестри  с 21,3±6,8 до 12,3±4,4% (p0,001). По данным инструментальных методов обследования определена эффективная непрямая декомпрессия: увеличение размера межтелового промежутка в среднем его отделе по сравнению с дооперационным значением с 8,6±3,1 до 15,7±4,2 мм (р0,001) и увеличение площади межпозвонковых отверстий — слева в среднем с 98,7±32,3 до 156,8±45,1 мм2 (р0,001), справа с 99,7±37,3 до 153,4±38,7 мм2 (р0,001). Также отмечено восстановление как сегментарного (с 10,2±3,8 до 13,6±6,7°; р0,001), так и регионарного (с 32,8±5,9 до 48,2±7,3°; р0,001) поясничного лордоза. Полноценный межтеловой спондилодез диагностирован у 87 (86,4%) пациентов. Осложнения наблюдались в 8,7% случаев.Заключение. Методика DLIF в сочетании с транскутанной транспедикулярной стабилизацией обладает высокой клинической эффективностью, подтвержденной значимым снижением выраженности болевого синдрома по ВАШ, улучшением качества жизни пациентов по индексу Освестри и низким количеством послеоперационных осложнений. Также описываемый симультанный минимально-инвазивный способ хирургического лечения пациентов с дегенеративными заболеваниями межпозвонковых дисков позволяет восстановить сагиттальный профиль поясничного отдела позвоночника и осуществить эффективную стабилизацию оперированных позвоночно-двигательных сегментов с высокой степенью формирования межтелового костного блока

Prospects of application of tubes made of duplex steels of a new generation in the heat exchanging equipment of nuclear power plants

Prospects of using tubes produced by Centravis Production Ukraine JSC of ferritic-austenitic (duplex) steels of a new generation according to the developed innovative technology in the heat exchanging equipment of nuclear power plants (NPP) were scientifically substantiated based on analysis of scientific and technical literature and the results obtained in comprehensive studies. Comparative corrosion studies of the tubes made of austenitic Cr-Ni and Cr-Ni-Mo steels and 02Cr22Ni5NМo3 (UNS S 31803) duplex steel have shown a substantially improved resistance of the latter to intercrystalline, pit and crevice corrosion, corrosion cracking and erosion. Presence of special lowenergy γ-γ, α-α grain boundaries and α-γ interphase boundaries characterized by an increased corrosion resistance and a contribution to the growth of steel durability as a whole was found for the first time in the structure of ferriticaustenitic steels.На основі аналізу науково-технічної літератури і результатів комплексних досліджень науково обґрунтована перспективність застосування труб з феритно-аустенітних (дуплексних) сталей нового покоління, які виготовляє за розробленою інноваційною технологією ПрАТ «Сентравіс Продакшн Юкрейн», у теплообмінному обладнання АЕС. Порівняльні дослідження корозійної тривкості труб з аустенітних CrNi- і Cr-Ni-Mo-сталей і дуплексної сталі 02Х22Н5АМ3 (UNS S 31803) показали значно вищу тривкість останніх проти міжкристалітної, пітінгової, виразкової, щілинної корозій, корозійного розтріскування і ерозії. Вперше встановлено наявність у структурі феритно-аустенітних сталей спеціальних низькоенергетичних границь зерен γ-γ і α-α і міжфазних границь α-γ, які характеризуються підвищеною корозійною тривкістю та сприяють підвищенню корозійної тривкості сталі в цілому.На основании анализа научно-технической литературы и результатов комплексных исследований научно обоснована перспективность использования труб из ферритно-аустенитных (дуплексных) сталей нового поколения, которые изготавливает по разработанной инновационной технологии ЧАО «Сентравис Продакшн Юкрейн», в теплообменном оборудовании АЭС. Сравнительные исследования коррозионной стойкости труб из аустенитных Cr-Ni- и Cr-Ni-Mo-сталей и дуплексной стали 02Х22Н5АМ3 (UNS S 31803) показали значительно более высокую стойкость последних против межкристаллитной, питтинговой, язвенной, щелевой коррозий, коррозионного растрескивания и эрозии. Впервые установлено наличие в структуре ферритно-аустенитных сталей специальных низкоэнергетических границ зерен γ-γ, α-α и межфазных границ α-γ, характеризующихся повышенной коррозионной стойкостью и способствующих повышению стойкости стали в целом

Search for direct production of charginos and neutralinos in events with three leptons and missing transverse momentum in √s = 7 TeV pp collisions with the ATLAS detector

A search for the direct production of charginos and neutralinos in final states with three electrons or muons and missing transverse momentum is presented. The analysis is based on 4.7 fb−1 of proton–proton collision data delivered by the Large Hadron Collider and recorded with the ATLAS detector. Observations are consistent with Standard Model expectations in three signal regions that are either depleted or enriched in Z-boson decays. Upper limits at 95% confidence level are set in R-parity conserving phenomenological minimal supersymmetric models and in simplified models, significantly extending previous results

Jet size dependence of single jet suppression in lead-lead collisions at sqrt(s(NN)) = 2.76 TeV with the ATLAS detector at the LHC

Measurements of inclusive jet suppression in heavy ion collisions at the LHC provide direct sensitivity to the physics of jet quenching. In a sample of lead-lead collisions at sqrt(s) = 2.76 TeV corresponding to an integrated luminosity of approximately 7 inverse microbarns, ATLAS has measured jets with a calorimeter over the pseudorapidity interval |eta| < 2.1 and over the transverse momentum range 38 < pT < 210 GeV. Jets were reconstructed using the anti-kt algorithm with values for the distance parameter that determines the nominal jet radius of R = 0.2, 0.3, 0.4 and 0.5. The centrality dependence of the jet yield is characterized by the jet "central-to-peripheral ratio," Rcp. Jet production is found to be suppressed by approximately a factor of two in the 10% most central collisions relative to peripheral collisions. Rcp varies smoothly with centrality as characterized by the number of participating nucleons. The observed suppression is only weakly dependent on jet radius and transverse momentum. These results provide the first direct measurement of inclusive jet suppression in heavy ion collisions and complement previous measurements of dijet transverse energy imbalance at the LHC.Comment: 15 pages plus author list (30 pages total), 8 figures, 2 tables, submitted to Physics Letters B. All figures including auxiliary figures are available at http://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/HION-2011-02

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

Measurement of D*+/- meson production in jets from pp collisions at sqrt(s) = 7 TeV with the ATLAS detector

This paper reports a measurement of D*+/- meson production in jets from proton-proton collisions at a center-of-mass energy of sqrt(s) = 7 TeV at the CERN Large Hadron Collider. The measurement is based on a data sample recorded with the ATLAS detector with an integrated luminosity of 0.30 pb^-1 for jets with transverse momentum between 25 and 70 GeV in the pseudorapidity range |eta| < 2.5. D*+/- mesons found in jets are fully reconstructed in the decay chain: D*+ -> D0pi+, D0 -> K-pi+, and its charge conjugate. The production rate is found to be N(D*+/-)/N(jet) = 0.025 +/- 0.001(stat.) +/- 0.004(syst.) for D*+/- mesons that carry a fraction z of the jet momentum in the range 0.3 < z < 1. Monte Carlo predictions fail to describe the data at small values of z, and this is most marked at low jet transverse momentum.Comment: 10 pages plus author list (22 pages total), 5 figures, 1 table, matches published version in Physical Review

Search for scalar top quark pair production in natural gauge mediated supersymmetry models with the ATLAS detector in pp collisions at sqrt(s) = 7 TeV

The results of a search for pair production of the lighter scalar partners of top quarks in 2.05 fb-1 of pp collisions at sqrt(s) =7 TeV using the ATLAS experiment at the LHC are reported. Scalar top quarks are searched for in events with two same flavour opposite-sign leptons (electrons or muons) with invariant mass consistent with the Z boson mass, large missing transverse momentum and jets in the final state. At least one of the jets is identified as originating from a b-quark. No excess over Standard Model expectations is found. The results are interpreted in the framework of R-parity conserving, gauge mediated Supersymmetry breaking `natural' scenarios, where the neutralino is the next-to-lightest supersymmetric particle. Scalar top quark masses up to 310 GeV are excluded for the lightest neutralino mass between 115 GeV and 230 GeV at 95% confidence level, reaching an exclusion of the scalar top quark mass of 330 GeV for the lightest neutralino mass of 190 GeV. Scalar top quark masses below 240 GeV are excluded for all values of the lightest neutralino mass above the Z boson mass.Comment: 7 pages plus author list (20 pages total), 4 figures, 1 table, matches published PLB versio