Cation distribution and interatomic interactions in oxides with heterovalent isomorphism:X. Structure of the Ho2SrAl2O7 oxide at 100, 298, and 673 K

Crystallochemical data for the Ho2SrAl2O7 oxide at 100, 293, and 6731 K were obtained by full-profile X-ray analysis. Analysis of the thermal expansion anisotropy showed that increased temperature gives rise to equalization of metal-oxygen bond lengths in all oxygen polyhedra at the expense of lengthening of' some bonds and virtual invariability of others

An Analytic Result for the Two-Loop Hexagon Wilson Loop in N = 4 SYM

In the planar N=4 supersymmetric Yang-Mills theory, the conformal symmetry constrains multi-loop n-edged Wilson loops to be basically given in terms of the one-loop n-edged Wilson loop, augmented, for n greater than 6, by a function of conformally invariant cross ratios. We identify a class of kinematics for which the Wilson loop exhibits exact Regge factorisation and which leave invariant the analytic form of the multi-loop n-edged Wilson loop. In those kinematics, the analytic result for the Wilson loop is the same as in general kinematics, although the computation is remarkably simplified with respect to general kinematics. Using the simplest of those kinematics, we have performed the first analytic computation of the two-loop six-edged Wilson loop in general kinematics.Comment: 17 pages. Extended discussion on how the QMRK limit is taken. Version accepted by JHEP. A text file containing the Mathematica code with the analytic expression for the 6-point remainder function is include

Form Factors in N=4 Super Yang-Mills and Periodic Wilson Loops

We calculate form factors of half-BPS operators in N=4 super Yang-Mills theory at tree level and one loop using novel applications of recursion relations and unitarity. In particular, we determine the expression of the one-loop form factors with two scalars and an arbitrary number of positive-helicity gluons. These quantities resemble closely the MHV scattering amplitudes, including holomorphicity of the tree-level form factor, and the expansion in terms of two-mass easy box functions of the one-loop result. Next, we compare our result for these form factors to the calculation of a particular periodic Wilson loop at one loop, finding agreement. This suggests a novel duality relating form factors to periodic Wilson loops.Comment: 26 pages, 10 figures. v2: typos fixed, comments adde

Large-Scale Sequence Analysis of Hemagglutinin of Influenza A Virus Identifies Conserved Regions Suitable for Targeting an Anti-Viral Response

BACKGROUND: Influenza A viral surface protein, hemagglutinin, is the major target of neutralizing antibody response and hence a main constituent of all vaccine formulations. But due to its marked evolutionary variability, vaccines have to be reformulated so as to include the hemagglutinin protein from the emerging new viral strain. With the constant fear of a pandemic, there is critical need for the development of anti-viral strategies that can provide wider protection against any Influenza A pathogen. An anti-viral approach that is directed against the conserved regions of the hemaggutinin protein has a potential to protect against any current and new Influenza A virus and provide a solution to this ever-present threat to public health. METHODOLOGY/PRINCIPAL FINDINGS: Influenza A human hemagglutinin protein sequences available in the NCBI database, corresponding to H1, H2, H3 and H5 subtypes, were used to identify highly invariable regions of the protein. Nine such regions were identified and analyzed for structural properties like surface exposure, hydrophilicity and residue type to evaluate their suitability for targeting an anti-peptide antibody/anti-viral response. CONCLUSION/SIGNIFICANCE: This study has identified nine conserved regions in the hemagglutinin protein, five of which have the structural characteristics suitable for an anti-viral/anti-peptide response. This is a critical step in the design of efficient anti-peptide antibodies as novel anti-viral agents against any Influenza A pathogen. In addition, these anti-peptide antibodies will provide broadly cross-reactive immunological reagents and aid the rapid development of vaccines against new and emerging Influenza A strains

Эффективность новых ингибиторов андрогенной оси в лечении гормоночувствительного рака предстательной железы у пациентов с висцеральными метастазами: систематический обзор и метаанализ

Background. The presence of visceral metastases (VM) is a significant adverse prognostic factor affecting the overall survival of patients with metastatic hormone-sensitive prostate cancer (mHSPC). Recently, new drugs, such as novel antiandrogen therapies (NAT), have been introduced, expanding the options for the treatment of mHSPC.Aim. To assess whether presence or absence of VM at baseline affects risk of death in patients with mHSPC receiving NAT therapy in combination with androgen deprivation therapy (ADT) compared with standard therapy (ADT ± 1st generation antiandrogen).Search strategy. Bibliographic databases PubMed and Google Scholar were searched from inception through January 21, 2022.Selection criteria. Eligible studies were randomized clinical trials with parallel design in patients with mHSPC. Subgroups of patients with or without VM at baseline were required. The following drugs were chosen as interventional agents: abiraterone acetate, apalutamide, enzalutamide, darolutamide. All in addition to ADT. The main outcome was overall survival.Data analysis. We applied the inverse variance technique for the meta-analysis of hazard ratios (HR). In HR analysis we adopted a fixed-effect model.Results. The analysis included three randomized clinical trials with 3376 patients, of which a total of 485 (14.4 %) patients had VM. Compared with ADT, the risk of death in patients with VM treated with NAT + ADT (HR 0.69; 95 % confidence interval (CI) 0.53–0.89; n = 485; p = 0.004) was similar to the risk of death in patients without VM (HR 0.66; 95 % CI 0.59–0.75; n = 2461; p <0.00001). The test for subgroup differences suggests that there is no statistically significant subgroup effect (χ2 = 0,05; df = 1; p = 0,82; I2 = 0 %). Ordered from the most to the least effective, treatments with improved overall survival in patients with VM when added to ADT included abiraterone acetate (HR 0.58; 95 % CI 0.41–0.82), apalutamide (HR 0.76; 95 % CI 0.47–1.23), enzalutamide (HR 1.05; 95 % CI 0.54–2.04). In patients without VM, the drugs are in the following order: enzalutamide (HR 0.62; 95 % CI 0.47–0.82), apalutamide (HR 0.65; 95 % CI 0.52–0.81), abiraterone acetate (HR 0.69; 95 % CI 0.58–0.82).Conclusion. Patients with mHSPC benefit from the combination of NAT with ADT, regardless of the presence or absence of VM (HR 0.67; 95 % CI 0.60–0.75; n = 2946; p <0,00001). Abiraterone acetate has the greatest advantages in reducing the risk of death in patients with VM.Введение. Наличие висцеральных метастазов (ВМ) является значимым неблагоприятным прогностическим фактором, влияющим на общую выживаемость пациентов с метастатическим гормоночувствительным раком предстательной железы (мГЧРПЖ). Возможности лекарственного лечения мГЧРПЖ за последние годы значительно расширились благодаря появлению новой антиандрогенной терапии (НААТ).Цель исследования – оценить, влияет ли исходное наличие или отсутствие ВМ на риск смерти пациентов с мГЧРПЖ, получающих НААТ в комбинации с андрогендепривационной терапией (АДТ), в сравнении со стандартной терапией (АДТ ± антиандроген 1-го поколения). Стратегия поиска. Поиск исследований выполняли в базах данных PubMed и Google Scholar. Последний поиск проводили 21 января 2022 г.Критерии отбора. В систематический обзор включали рандомизированные клинические исследования с параллельным дизайном, в которых участвовали пациенты с мГЧРПЖ и в которых отдельно выделяли подгруппы больных с ВМ и без них. В качестве интервенционного воздействия были выбраны следующие лекарственные препараты: абиратерона ацетат, апалутамид, энзалутамид, даролутамид. Препараты применяли на фоне продолжающейся АДТ. Исследования должны были включать в качестве конечной точки оценку общей выживаемости.Анализ данных. Для метаанализа отношений рисков (ОР) был применен метод обратной дисперсии. При анализе ОР использовали модель фиксированного эффекта.Результаты. В анализ было включено 3 рандомизированных клинических исследования, насчитывающих 3376 пациентов, из них с ВМ суммарно 485 (14,4 %) больных. При сравнении с АДТ риск смерти больных с ВМ, получавших НААТ + АДТ (ОР 0,69; 95 % доверительный интервал (ДИ) 0,53–0,89; n = 485; p = 0,004), был сопоставим с риском смерти пациентов без ВМ (ОР 0,66; 95 % ДИ 0,59–0,75; n = 2461; p <0,00001). Различие эффектов в подгруппах c ВМ и без них было статистически незначимо (χ2 = 0,05; df = 1; p = 0,82; I2 = 0 %). В соответствии с результатами рандомизированных клинических исследований порядок препаратов, увеличивающих общую выживаемость пациентов с мГЧРПЖ и ВМ, от наиболее до наименее эффективного выглядит следующим образом: абиратерона ацетат (ОР 0,58; 95 % ДИ 0,41–0,82), апалутамид (ОР 0,76; 95 % ДИ 0,47–1,23), энзалутамид (ОР 1,05; 95 % ДИ 0,54–2,04). У пациентов без ВМ наибольшей эффективностью в отношении общей выживаемости обладает энзалутамид (ОР 0,62; 95 % ДИ 0,47–0,82), далее следуют апалутамид (ОР 0,65; 95 % ДИ 0,52–0,81) и абиратерона ацетат (ОР 0,69; 95 % ДИ 0,58–0,82).Заключение. Пациенты с мГЧРПЖ получают пользу от комбинации НААТ с АДТ независимо от наличия или отсутствия ВМ (ОР 0,67; 95 % ДИ 0,60–0,75; n = 2946; p <0,00001). Абиратерона ацетат обладает наибольшими преимуществами в снижении риска смерти в подгруппе больных с ВМ

On soft singularities at three loops and beyond

We report on further progress in understanding soft singularities of massless gauge theory scattering amplitudes. Recently, a set of equations was derived based on Sudakov factorization, constraining the soft anomalous dimension matrix of multi-leg scattering amplitudes to any loop order, and relating it to the cusp anomalous dimension. The minimal solution to these equations was shown to be a sum over color dipoles. Here we explore potential contributions to the soft anomalous dimension that go beyond the sum-over-dipoles formula. Such contributions are constrained by factorization and invariance under rescaling of parton momenta to be functions of conformally invariant cross ratios. Therefore, they must correlate the color and kinematic degrees of freedom of at least four hard partons, corresponding to gluon webs that connect four eikonal lines, which first appear at three loops. We analyze potential contributions, combining all available constraints, including Bose symmetry, the expected degree of transcendentality, and the singularity structure in the limit where two hard partons become collinear. We find that if the kinematic dependence is solely through products of logarithms of cross ratios, then at three loops there is a unique function that is consistent with all available constraints. If polylogarithms are allowed to appear as well, then at least two additional structures are consistent with the available constraints.Comment: v2: revised version published in JHEP (minor corrections in Sec. 4; added discussion in Sec. 5.3; refs. added); v3: minor corrections (eqs. 5.11, 5.12 and 5.29); 38 pages, 3 figure

Observation of a J^PC = 1-+ exotic resonance in diffractive dissociation of 190 GeV/c pi- into pi- pi- pi+

The COMPASS experiment at the CERN SPS has studied the diffractive dissociation of negative pions into the pi- pi- pi+ final state using a 190 GeV/c pion beam hitting a lead target. A partial wave analysis has been performed on a sample of 420000 events taken at values of the squared 4-momentum transfer t' between 0.1 and 1 GeV^2/c^2. The well-known resonances a1(1260), a2(1320), and pi2(1670) are clearly observed. In addition, the data show a significant natural parity exchange production of a resonance with spin-exotic quantum numbers J^PC = 1-+ at 1.66 GeV/c^2 decaying to rho pi. The resonant nature of this wave is evident from the mass-dependent phase differences to the J^PC = 2-+ and 1++ waves. From a mass-dependent fit a resonance mass of 1660 +- 10+0-64 MeV/c^2 and a width of 269+-21+42-64 MeV/c^2 is deduced.Comment: 7 page, 3 figures; version 2 gives some more details, data unchanged; version 3 updated authors, text shortened, data unchange

Search for new phenomena in final states with an energetic jet and large missing transverse momentum in pp collisions at √ s = 8 TeV with the ATLAS detector

Results of a search for new phenomena in final states with an energetic jet and large missing transverse momentum are reported. The search uses 20.3 fb−1 of √ s = 8 TeV data collected in 2012 with the ATLAS detector at the LHC. Events are required to have at least one jet with pT > 120 GeV and no leptons. Nine signal regions are considered with increasing missing transverse momentum requirements between Emiss T > 150 GeV and Emiss T > 700 GeV. Good agreement is observed between the number of events in data and Standard Model expectations. The results are translated into exclusion limits on models with either large extra spatial dimensions, pair production of weakly interacting dark matter candidates, or production of very light gravitinos in a gauge-mediated supersymmetric model. In addition, limits on the production of an invisibly decaying Higgs-like boson leading to similar topologies in the final state are presente

Jet energy measurement with the ATLAS detector in proton-proton collisions at root s=7 TeV

The jet energy scale and its systematic uncertainty are determined for jets measured with the ATLAS detector at the LHC in proton-proton collision data at a centre-of-mass energy of √s = 7TeV corresponding to an integrated luminosity of 38 pb-1. Jets are reconstructed with the anti-kt algorithm with distance parameters R=0. 4 or R=0. 6. Jet energy and angle corrections are determined from Monte Carlo simulations to calibrate jets with transverse momenta pT≥20 GeV and pseudorapidities {pipe}η{pipe}<4. 5. The jet energy systematic uncertainty is estimated using the single isolated hadron response measured in situ and in test-beams, exploiting the transverse momentum balance between central and forward jets in events with dijet topologies and studying systematic variations in Monte Carlo simulations. The jet energy uncertainty is less than 2. 5 % in the central calorimeter region ({pipe}η{pipe}<0. 8) for jets with 60≤pT<800 GeV, and is maximally 14 % for pT<30 GeV in the most forward region 3. 2≤{pipe}η{pipe}<4. 5. The jet energy is validated for jet transverse momenta up to 1 TeV to the level of a few percent using several in situ techniques by comparing a well-known reference such as the recoiling photon pT, the sum of the transverse momenta of tracks associated to the jet, or a system of low-pT jets recoiling against a high-pT jet. More sophisticated jet calibration schemes are presented based on calorimeter cell energy density weighting or hadronic properties of jets, aiming for an improved jet energy resolution and a reduced flavour dependence of the jet response. The systematic uncertainty of the jet energy determined from a combination of in situ techniques is consistent with the one derived from single hadron response measurements over a wide kinematic range. The nominal corrections and uncertainties are derived for isolated jets in an inclusive sample of high-pT jets. Special cases such as event topologies with close-by jets, or selections of samples with an enhanced content of jets originating from light quarks, heavy quarks or gluons are also discussed and the corresponding uncertainties are determined. © 2013 CERN for the benefit of the ATLAS collaboration

X-ray emission from the Sombrero galaxy: discrete sources

We present a study of discrete X-ray sources in and around the bulge-dominated, massive Sa galaxy, Sombrero (M104), based on new and archival Chandra observations with a total exposure of ~200 ks. With a detection limit of L_X = 1E37 erg/s and a field of view covering a galactocentric radius of ~30 kpc (11.5 arcminute), 383 sources are detected. Cross-correlation with Spitler et al.'s catalogue of Sombrero globular clusters (GCs) identified from HST/ACS observations reveals 41 X-rays sources in GCs, presumably low-mass X-ray binaries (LMXBs). We quantify the differential luminosity functions (LFs) for both the detected GC and field LMXBs, whose power-low indices (~1.1 for the GC-LF and ~1.6 for field-LF) are consistent with previous studies for elliptical galaxies. With precise sky positions of the GCs without a detected X-ray source, we further quantify, through a fluctuation analysis, the GC LF at fainter luminosities down to 1E35 erg/s. The derived index rules out a faint-end slope flatter than 1.1 at a 2 sigma significance, contrary to recent findings in several elliptical galaxies and the bulge of M31. On the other hand, the 2-6 keV unresolved emission places a tight constraint on the field LF, implying a flattened index of ~1.0 below 1E37 erg/s. We also detect 101 sources in the halo of Sombrero. The presence of these sources cannot be interpreted as galactic LMXBs whose spatial distribution empirically follows the starlight. Their number is also higher than the expected number of cosmic AGNs (52+/-11 [1 sigma]) whose surface density is constrained by deep X-ray surveys. We suggest that either the cosmic X-ray background is unusually high in the direction of Sombrero, or a distinct population of X-ray sources is present in the halo of Sombrero.Comment: 11 figures, 5 tables, ApJ in pres