This paper will discuss the design and construction of BESIII [1], which is designed to study physics in the τ-charm energy region utilizing the new high luminosity BEPCII double ring e + ecollider [2]. The expected performance will be given based on Monte Carlo simulations and results of cosmic ray and beam tests. In BESIII, tracking and momentum measurements for charged particles are made by a cylindrical multilayer drift chamber in a 1 T superconducting solenoid. Charged particles are identified with a time-of-flight system based on plastic scintillators in conjunction with dE/dx (energy loss per unit pathlength) measurements in the drift chamber. Energies of electromagnetic showers are measured by a CsI(Tl) crystal calorimeter located inside the solenoid magnet. Muons are identified by arrays of resistive plate chambers in the steel magnetic flux return. The level 1 trigger system, Data Acquisition system and the event filter system based on networked computers will also be described.

Sulfonated (SO3H-bearing) activated carbon (AC-SO3H) was synthesized by an aryl diazonium salt reduction process. The obtained material had a SO3H density of 0.64 mmol·g−1 and a specific surface area of 602 m2·g−1. The catalytic properties of AC-SO3H were compared with that of two commercial solid acid catalysts, Nafion NR50 and Amberlyst-15. In a 10-h esterification reaction of acetic acid with ethanol, the acid conversion with AC-SO3H (78%) was lower than that of Amberlyst-15 (86%), which could be attributed to the fact that the SO3H density of the sulfonated carbon was lower than that of Amberlyst-15 (4.60 mmol·g−1). However, AC-SO3H exhibited comparable and even much higher catalytic activities than the commercial catalysts in the esterification of aliphatic acids with longer carbon chains such as hexanoic acid and decanoic acid, which may be due to the large specific surface area and mesoporous structures of the activated carbon. The disadvantage of AC-SO3H is the leaching of SO3H group during the reactions.

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The ATLAS detector at the Large Hadron Collider is used to search for the lepton flavor violating process Z → eμ in pp collisions using 20.3 fb −1 of data collected at ffiffi ffi s p ¼ 8 TeV. An enhancement in the eμ invariant mass spectrum is searched for at the Z-boson mass. The number of Z bosons produced in the data sample is estimated using events of similar topology, Z → ee and μμ, significantly reducing the systematic uncertainty in the measurement. There is no evidence of an enhancement at the Z-boson mass, resulting in an upper limit on the branching fraction, BðZ → eμÞ < 7.5 × 10 −7 at the 95% confidence level. DOI: 10.1103/PhysRevD.90.072010 PACS numbers: 12.60.-i I. INTRODUCTIONLepton flavor conservation in the charged lepton sector is a fundamental assumption of the Standard Model (SM) but there is no associated symmetry. Thus, searches for lepton flavor violation (LFV) processes are good candidates for probing new physics. The observation of neutrino oscillations is a clear indication of LFV in the neutral lepton sector; however, such an oscillation mechanism cannot induce observable LFV in the charged lepton sector. All searches in the charged lepton sector have produced null results so far [1]. Lepton flavor violation in the charged lepton sector may have a different origin than LFV induced by neutrino oscillations and the search for this effect provides constraints on theories beyond the SM (see for example Refs. [2][3][4]).In this paper, a search for the lepton flavor violating decay Z → eμ is presented. There are stringent experimental limits on other charged lepton flavor violating processes, which can be used to derive an upper limit on the branching fraction for Z → eμ with some theoretical assumptions. For example, the upper limit on μ → 3e yields BðZ → eμÞ < 10 −12 [5] and on μ → eγ yields BðZ → eμÞ < 10 −10 [6]. The experiments at the Large Electron-Positron Collider (LEP) searched directly for the decay Z → eμ [7-10]. The most stringent upper limit is BðZ → eμÞ < 1.7 × 10 −6 at the 95% confidence level (C.L.) using a data sample of 5.0 × 10 6 Z bosons produced in e þ e − collisions at ffiffi ffi s p ¼ 88-94GeV [7]. The Large Hadron Collider (LHC) has already produced many more Z bosons in pp collisions, but with substantially more background. In this paper, the 20.3 AE 0.6 fb −1 [11] of data collected at ffiffi ffi s p ¼ 8 TeV by the ATLAS experiment corresponds to 7.8 × 10 8 Z bosons produced. Despite the larger background at the LHC, a more restrictive direct limit on the Z → eμ decay is reported in this paper. II. ATLAS DETECTORThe ATLAS detector [12] consists of an inner detector (ID) surrounded by a solenoid that produces a 2 T magnetic field, electromagnetic and hadronic calorimeters, and a muon spectrometer (MS) immersed in a magnetic field produced by a system of toroids. The ID measures the trajectories of charged particles over the full azimuthal angle and in a pseudorapidity [13] range of jηj < 2.5 using silicon pixel, silicon microstrip, and straw-tube transitionradiation ...

BackgroundLong intergenic noncoding RNA p21 (lincRNA-p21) is considered a target of wild-type p53, but little is known about its regulation by mutant p53 and its functions during the progression of head and neck squamous cell carcinoma (HNSCC).MethodsRNAscope was used to detect the expression and distribution of lincRNA-p21. Chromatin immunoprecipitation and electrophoretic mobility shift assays were performed to analyze the transcriptional regulation of lincRNA-p21 in HNSCC cells. The biological functions of lincRNA-p21 were investigated in vitro and in vivo. RNA immunoprecipitation and pull-down assays were used to detect the direct binding of lincRNA-p21.ResultsLower lincRNA-p21 expression was observed in HNSCC tissues and indicated worse prognosis. Both wild and mutant type p53 transcriptionally regulated lincRNA-p21, but nuclear transcription factor Y subunit alpha (NF-YA) was essential for mutant p53 in the regulation of lincRNA-p21. Ectopic expression of lincRNA-p21 significantly inhibited cell proliferation capacity in vitro and in vivo and vice versa. Moreover, the overexpression of lincRNA-p21 induced G1 arrest and apoptosis. Knockdown NF-YA expression reversed tumor suppressor activation of lincRNA-p21 in mutant p53 cells, not wild-type p53 cells. A negative correlation was observed between lincRNA-p21 and the phosphorylation of signal transducer and activator of transcription 3 (p-STAT3) in HNSCC tissues. High lincRNA-p21 expression inhibited Janus kinase 2 (JAK2)/STAT3 signal activation and vice versa. Further, we observed direct binding to STAT3 by lincRNA-p21 in HNSCC cells, which suppressed STAT3-induced oncogenic potential.ConclusionsOur results revealed the transcriptional regulation of lincRNA-p21 by the mutant p53/NF-YA complex in HNSCC. LincRNA-p21 acted as a tumor suppressor in HNSCC progression, which was attributed to direct binding to STAT3 and blocking of JAK2/STAT3 signaling.Electronic supplementary materialThe online version of this article (10.1186/s12943-019-0993-3) contains supplementary material, which is available to authorized users.

Using 2.92 fb −1 of electron-positron annihilation data collected at √ s = 3.773 GeV with the BESIII detector, we obtain the first measurements of the absolute branching fractionL e + νe differential decay rate distribution, the product of the hadronic form factor and the magnitude of the CKM matrix element, f K + (0)|Vcs|, is determined 3 to be 0.728 ± 0.006(stat.) ± 0.011(sys.). Using |Vcs| from the SM constrained fit with the measured f K + (0)|Vcs|, f K + (0) = 0.748 ± 0.007(stat.) ± 0.012(sys.) is obtained, and utilizing the unquenched LQCD calculation for f K + (0), |Vcs| = 0.975 ± 0.008(stat.) ± 0.015(sys.) ± 0.025(LQCD).

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Acyclic enediynes are generally inactive under physiological conditions to be used as antitumor agents like their natural enediyne counterparts. A new mechanism named as maleimide-assisted rearrangement and cycloaromatization (MARACA) is uncovered to trigger the reactivity of acyclic enediynes. Through this mechanism, cascade 1,3-proton transfer processes are accelerated with the maleimide moiety at the ene position to enable the acyclic enediynes to undergo cycloaromatization and generate reactive radicals under physiological conditions. Computational studies suggest that the highest energy barrier for MARACA is 26.0 kcal/mol, much lower than that of Bergman cyclization pathway (39.6 kcal/mol). Experimental results show that maleimide-based enediynes exhibit low onset temperature, fast generation of radical species at 37 °C, and much faster reaction in aqueous solution than in nonpolar solvent, which is beneficial to achieve both high reactivity in physiological environment and high stability for storage and delivery in nonpolar media. The generated radical species are capable of causing high percentage of double-strand (ds) DNA cleavage, leading to significant cytotoxicity toward a panel of cancer cell lines with half inhibition concentration down to submicromolar level. Overall, the discovery of the MARACA mechanism provides a platform for designing novel acyclic enediynes with high potency for antitumor applications.