Nonlinear growth of firehose and mirror fluctuations in turbulent galaxy-cluster plasmas

In turbulent high-beta astrophysical plasmas (exemplified by the galaxy cluster plasmas), pressure-anisotropy-driven firehose and mirror fluctuations grow nonlinearly to large amplitudes, dB/B ~ 1, on a timescale comparable to the turnover time of the turbulent motions. The principle of their nonlinear evolution is to generate secularly growing small-scale magnetic fluctuations that on average cancel the temporal change in the large-scale magnetic field responsible for the pressure anisotropies. The presence of small-scale magnetic fluctuations may dramatically affect the transport properties and, thereby, the large-scale dynamics of the high-beta astrophysical plasmas.Comment: revtex, 4 pages, 1 figure; replaced to match published versio

PROGNOSTIC VALUE OF pSTAT3 EXPRESSION IN DIFFUSIVE B-LARGE CELL LYMPHOMA IN THE RUSSIAN PATIENT SAMPLE

The aim of the study was to evaluate the prognostic value of pSTAT3 expression in diffuse B-large cell lymphoma (DLBCL) in a Russian sample of patients. Material and methods. Retrospectively, the results of an examination of 50 patients with newly diagnosed DLBCL in the period from 2014 to 2017 were evaluated. Using immunohistochemical and morphometric methods, the relative number of tumor cells expressing pSTAT3 was determined. The relationship of various levels of marker expression with clinical and laboratory parameters was analyzed, and long-term results of patient therapy were evaluated. Results and discussion. The overexpression of pSTAT3 protein is associated with a non-GCB subtype of the disease, an advanced stage, the patients of 60 years and older age, as well as with a lower frequency of achieving complete remissions with DLBCL. Patients with a high degree of marker expression in tumor cells had lower rates of overall (OS) and progressive survival (PFS). It was revealed that the marker under study has good predictive ability, but is not an independent prognosis factor for DLBCL. Conclusions. The level of expression of pSTAT3 is an informative factor that allows predicting the response to standard therapy for diffuse B-large cell lymphoma. The indicated marker may be useful for identifying patients who need individualization of therapeutic tactics for this disease

Значение экспрессии рАКТ1 при диффузной В-крупноклеточной лимфоме

Aim. To evaluate the prognostic value of pAKT1 expression by tumor cells in patients with diffuse large B-cell lymphoma.Materials and methods. The study included 90 patients with newly diagnosed diffuse large B-cell lymphoma (DLBCL), who were treated at the clinic of Kirov Research Institute of Hematology and Blood Transfusion from 2014 to 2017 and received standard first-line polychemotherapy according to the R-CHOP regimen. Using immunohistochemical and morphometric methods, the relative number of tumor cells expressing pAKT1 was determined. Using the two-sided Fisher’s exact test, the relationship of different levels of marker expression with clinical and laboratory parameters of patients and long-term treatment results was analyzed. The impact of pAKT1 on the risk of an adverse event was assessed using the Cox regression analysis.Results. Overexpression of pAKT1 is associated with unfavorable clinical characteristics of patients with DLBCL, excessive expression of the BCL2 and c-Myc oncoproteins, as well as with low rates of overall and progressive survival. Overexpression of pAKT1 is an independent prognostic factor and statistically significantly affects the risk of an adverse outcome in DLBCL.Conclusion. The degree of pAKT1 expression is an informative criterion that allows to predict the course of diffuse large B-cell lymphoma. It is advisable to use the indicated marker when stratifying patients into risk groups.Цель – оценить прогностическое значение экспрессии рАКТ1 опухолевыми клетками у больных диффузной В-крупноклеточной лимфомой.Материалы и методы. В исследование включены 90 пациентов с впервые диагностированной диффузной В-крупноклеточной лимфомой (ДВККЛ), наблюдавшиеся в клинике института с 2014 по 2017 г. и получавшие стандартную полихимиотерапию первой линии по схеме R-CHOP. С помощью иммуногистохимического и морфометрического методов определено относительное количество экспрессирующих рАКТ1 опухолевых клеток. С помощью точного двухстороннего критерия Фишера проанализирована взаимосвязь различных уровней экспрессии маркера с клинико-лабораторными показателями пациентов и отдаленными результатами лечения. Оценку влияния рАКТ1 на риск наступления неблагоприятного события проводили с помощью регрессионного анализа Кокса.Результаты. Гиперэкспрессия рАКТ1 ассоциирована с неблагоприятными клиническими характеристиками больных диффузной В-крупноклеточной лимфомой, избыточной экспрессией онкобелков BCL2, cMyc, а также низкими показателями общей и беспрогрессивной выживаемости. Гиперэкспрессия рАКТ1 является независимым фактором прогноза и статистически значимо влияет на риск возникновения неблагоприятного исхода при ДВККЛ.Заключение. Степень экспрессии рАКТ1 является информативным критерием, позволяющим прогнозировать течение диффузной В-крупноклеточной лимфомы. Указанный маркер целесообразно использовать при стратификации пациентов на группы риска

De novo mutations in SMCHD1 cause Bosma arhinia microphthalmia syndrome and abrogate nasal development

Bosma arhinia microphthalmia syndrome (BAMS) is an extremely rare and striking condition characterized by complete absence of the nose with or without ocular defects. We report here that missense mutations in the epigenetic regulator SMCHD1 mapping to the extended ATPase domain of the encoded protein cause BAMS in all 14 cases studied. All mutations were de novo where parental DNA was available. Biochemical tests and in vivo assays in Xenopus laevis embryos suggest that these mutations may behave as gain-of-function alleles. This finding is in contrast to the loss-of-function mutations in SMCHD1 that have been associated with facioscapulohumeral muscular dystrophy (FSHD) type 2. Our results establish SMCHD1 as a key player in nasal development and provide biochemical insight into its enzymatic function that may be exploited for development of therapeutics for FSHD

Oval Domes: History, Geometry and Mechanics

An oval dome may be defined as a dome whose plan or profile (or both) has an oval form. The word Aoval@ comes from the latin Aovum@, egg. Then, an oval dome has an egg-shaped geometry. The first buildings with oval plans were built without a predetermined form, just trying to close an space in the most economical form. Eventually, the geometry was defined by using arcs of circle with common tangents in the points of change of curvature. Later the oval acquired a more regular form with two axis of symmetry. Therefore, an “oval” may be defined as an egg-shaped form, doubly symmetric, constructed with arcs of circle; an oval needs a minimum of four centres, but it is possible also to build polycentric ovals. The above definition corresponds with the origin and the use of oval forms in building and may be applied without problem until, say, the XVIIIth century. Since then, the teaching of conics in the elementary courses of geometry made the cultivated people to define the oval as an approximation to the ellipse, an “imperfect ellipse”: an oval was, then, a curve formed with arcs of circles which tries to approximate to the ellipse of the same axes. As we shall see, the ellipse has very rarely been used in building. Finally, in modern geometrical textbooks an oval is defined as a smooth closed convex curve, a more general definition which embraces the two previous, but which is of no particular use in the study of the employment of oval forms in building. The present paper contains the following parts: 1) an outline the origin and application of the oval in historical architecture; 2) a discussion of the spatial geometry of oval domes, i. e., the different methods employed to trace them; 3) a brief exposition of the mechanics of oval arches and domes; and 4) a final discussion of the role of Geometry in oval arch and dome design

Measurement of the t t-bar production cross section in the dilepton channel in pp collisions at sqrt(s) = 7 TeV

The t t-bar production cross section (sigma[t t-bar]) is measured in proton-proton collisions at sqrt(s) = 7 TeV in data collected by the CMS experiment, corresponding to an integrated luminosity of 2.3 inverse femtobarns. The measurement is performed in events with two leptons (electrons or muons) in the final state, at least two jets identified as jets originating from b quarks, and the presence of an imbalance in transverse momentum. The measured value of sigma[t t-bar] for a top-quark mass of 172.5 GeV is 161.9 +/- 2.5 (stat.) +5.1/-5.0 (syst.) +/- 3.6(lumi.) pb, consistent with the prediction of the standard model.Comment: Replaced with published version. Included journal reference and DO

Combined search for the quarks of a sequential fourth generation

Results are presented from a search for a fourth generation of quarks produced singly or in pairs in a data set corresponding to an integrated luminosity of 5 inverse femtobarns recorded by the CMS experiment at the LHC in 2011. A novel strategy has been developed for a combined search for quarks of the up and down type in decay channels with at least one isolated muon or electron. Limits on the mass of the fourth-generation quarks and the relevant Cabibbo-Kobayashi-Maskawa matrix elements are derived in the context of a simple extension of the standard model with a sequential fourth generation of fermions. The existence of mass-degenerate fourth-generation quarks with masses below 685 GeV is excluded at 95% confidence level for minimal off-diagonal mixing between the third- and the fourth-generation quarks. With a mass difference of 25 GeV between the quark masses, the obtained limit on the masses of the fourth-generation quarks shifts by about +/- 20 GeV. These results significantly reduce the allowed parameter space for a fourth generation of fermions.Comment: Replaced with published version. Added journal reference and DO

Search for the standard model Higgs boson in the H to ZZ to 2l 2nu channel in pp collisions at sqrt(s) = 7 TeV

A search for the standard model Higgs boson in the H to ZZ to 2l 2nu decay channel, where l = e or mu, in pp collisions at a center-of-mass energy of 7 TeV is presented. The data were collected at the LHC, with the CMS detector, and correspond to an integrated luminosity of 4.6 inverse femtobarns. No significant excess is observed above the background expectation, and upper limits are set on the Higgs boson production cross section. The presence of the standard model Higgs boson with a mass in the 270-440 GeV range is excluded at 95% confidence level.Comment: Submitted to JHE

Azimuthal anisotropy of charged particles at high transverse momenta in PbPb collisions at sqrt(s[NN]) = 2.76 TeV

The azimuthal anisotropy of charged particles in PbPb collisions at nucleon-nucleon center-of-mass energy of 2.76 TeV is measured with the CMS detector at the LHC over an extended transverse momentum (pt) range up to approximately 60 GeV. The data cover both the low-pt region associated with hydrodynamic flow phenomena and the high-pt region where the anisotropies may reflect the path-length dependence of parton energy loss in the created medium. The anisotropy parameter (v2) of the particles is extracted by correlating charged tracks with respect to the event-plane reconstructed by using the energy deposited in forward-angle calorimeters. For the six bins of collision centrality studied, spanning the range of 0-60% most-central events, the observed v2 values are found to first increase with pt, reaching a maximum around pt = 3 GeV, and then to gradually decrease to almost zero, with the decline persisting up to at least pt = 40 GeV over the full centrality range measured.Comment: Replaced with published version. Added journal reference and DO

Search for anomalous t t-bar production in the highly-boosted all-hadronic final state

A search is presented for a massive particle, generically referred to as a Z', decaying into a t t-bar pair. The search focuses on Z' resonances that are sufficiently massive to produce highly Lorentz-boosted top quarks, which yield collimated decay products that are partially or fully merged into single jets. The analysis uses new methods to analyze jet substructure, providing suppression of the non-top multijet backgrounds. The analysis is based on a data sample of proton-proton collisions at a center-of-mass energy of 7 TeV, corresponding to an integrated luminosity of 5 inverse femtobarns. Upper limits in the range of 1 pb are set on the product of the production cross section and branching fraction for a topcolor Z' modeled for several widths, as well as for a Randall--Sundrum Kaluza--Klein gluon. In addition, the results constrain any enhancement in t t-bar production beyond expectations of the standard model for t t-bar invariant masses larger than 1 TeV.Comment: Submitted to the Journal of High Energy Physics; this version includes a minor typo correction that will be submitted as an erratu