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  1. Pagliaro S, Sacchi S, Pacilli MG, Brambilla M, Lionetti F, Bettache K, et al.
    PLoS One, 2021;16(3):e0248334.
    PMID: 33690672 DOI: 10.1371/journal.pone.0248334
    The worldwide spread of a new coronavirus (SARS-CoV-2) since December 2019 has posed a severe threat to individuals' well-being. While the world at large is waiting that the released vaccines immunize most citizens, public health experts suggest that, in the meantime, it is only through behavior change that the spread of COVID-19 can be controlled. Importantly, the required behaviors are aimed not only at safeguarding one's own health. Instead, individuals are asked to adapt their behaviors to protect the community at large. This raises the question of which social concerns and moral principles make people willing to do so. We considered in 23 countries (N = 6948) individuals' willingness to engage in prescribed and discretionary behaviors, as well as country-level and individual-level factors that might drive such behavioral intentions. Results from multilevel multiple regressions, with country as the nesting variable, showed that publicized number of infections were not significantly related to individual intentions to comply with the prescribed measures and intentions to engage in discretionary prosocial behaviors. Instead, psychological differences in terms of trust in government, citizens, and in particular toward science predicted individuals' behavioral intentions across countries. The more people endorsed moral principles of fairness and care (vs. loyalty and authority), the more they were inclined to report trust in science, which, in turn, statistically predicted prescribed and discretionary behavioral intentions. Results have implications for the type of intervention and public communication strategies that should be most effective to induce the behavioral changes that are needed to control the COVID-19 outbreak.
  2. Mao Y, Raju G, Zabidi MA
    Nat Sci Sleep, 2023;15:931-947.
    PMID: 38021213 DOI: 10.2147/NSS.S431442
    Occupational stress and sleep quality are prevalent issues that can impact the physical and mental well-being of adults. An association between occupational stress and sleep quality has been found. However, this association is not entirely the same across different occupational groups. Additionally, variations are present in the research design and instruments employed.This systematic review aims to investigate the association between these two factors and identify gaps and limitations in current research. Articles published between January 1, 2011, and December 31, 2022, were retrieved from the WOS, Scopus, and PubMed databases. Out of 1225 articles, 38 studies met the predetermined inclusion and exclusion criteria and were included in the review. In the study, research designs, samples, instruments, and associations between occupational stress and sleep quality were statistically analyzed.These studies encompassed a diverse range of occupations, including both blue-collar and white-collar workers. Cross-sectional study is the most common research method. The Pittsburgh Sleep Quality Index (PSQI) was the most frequently utilized tool for assessing sleep quality, while there was a wide variety of measurement tools employed to assess occupational stress. The association between occupational stress and sleep quality consistently demonstrated a negative association, although the specific dimensions varied among studies. Moreover, several other factors were identified to have direct or indirect effects on occupational stress and sleep quality. For future research in this field, we propose four recommendations: (1) Consider utilizing objective measures to assess occupational stress and sleep quality. (2) Employ controlled experiments to further validate the causal relationship between occupational stress and sleep quality. (3) Investigate occupational groups that have received less attention. (4) Take into account the potential influence of other factors on occupational stress and sleep quality.
  3. CMS Collaboration, Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Bergauer T, et al.
    Eur Phys J C Part Fields, 2014 09 26;74(9):3036.
    PMID: 25814912
    Searches for the direct electroweak production of supersymmetric charginos, neutralinos, and sleptons in a variety of signatures with leptons and [Formula: see text], [Formula: see text], and Higgs bosons are presented. Results are based on a sample of proton-proton collision data collected at center-of-mass energy [Formula: see text] with the CMS detector in 2012, corresponding to an integrated luminosity of 19.5 [Formula: see text]. The observed event rates are in agreement with expectations from the standard model. These results probe charginos and neutralinos with masses up to 720 [Formula: see text], and sleptons up to 260 [Formula: see text], depending on the model details.
  4. CMS Collaboration, Chatrchyan S, Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, et al.
    Eur Phys J C Part Fields, 2014 08 07;74(8):2973.
    PMID: 25814904
    Measurements are reported of the WZ and ZZ production cross sections in proton-proton collisions at [Formula: see text][Formula: see text] in final states where one Z boson decays to b-tagged jets. The other gauge boson, either W or Z, is detected through its leptonic decay (either [Formula: see text], [Formula: see text] or [Formula: see text], [Formula: see text], or [Formula: see text]). The results are based on data corresponding to an integrated luminosity of 18.9 fb[Formula: see text] collected with the CMS detector at the Large Hadron Collider. The measured cross sections, [Formula: see text] and [Formula: see text], are consistent with next-to-leading order quantum chromodynamics calculations.
  5. CMS Collaboration, Chatrchyan S, Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, et al.
    Eur Phys J C Part Fields, 2014 08 20;74(8):3014.
    PMID: 25814909
    The normalised differential top quark-antiquark production cross section is measured as a function of the jet multiplicity in proton-proton collisions at a centre-of-mass energy of 7[Formula: see text] at the LHC with the CMS detector. The measurement is performed in both the dilepton and lepton+jets decay channels using data corresponding to an integrated luminosity of 5.0[Formula: see text]. Using a procedure to associate jets to decay products of the top quarks, the differential cross section of the [Formula: see text] production is determined as a function of the additional jet multiplicity in the lepton+jets channel. Furthermore, the fraction of events with no additional jets is measured in the dilepton channel, as a function of the threshold on the jet transverse momentum. The measurements are compared with predictions from perturbative quantum chromodynamics and no significant deviations are observed.
  6. CMS Collaboration, Chatrchyan S, Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, et al.
    Eur Phys J C Part Fields, 2014 11 12;74(11):3129.
    PMID: 25814874
    A measurement of differential cross sections for the production of a pair of isolated photons in proton-proton collisions at [Formula: see text] is presented. The data sample corresponds to an integrated luminosity of 5.0[Formula: see text] collected with the CMS detector. A data-driven isolation template method is used to extract the prompt diphoton yield. The measured cross section for two isolated photons, with transverse energy above 40 and 25[Formula: see text] respectively, in the pseudorapidity range [Formula: see text], [Formula: see text] and with an angular separation [Formula: see text], is [Formula: see text][Formula: see text]. Differential cross sections are measured as a function of the diphoton invariant mass, the diphoton transverse momentum, the azimuthal angle difference between the two photons, and the cosine of the polar angle in the Collins-Soper reference frame of the diphoton system. The results are compared to theoretical predictions at leading, next-to-leading, and next-to-next-to-leading order in quantum chromodynamics.
  7. CMS Collaboration, Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Bergauer T, et al.
    Eur Phys J C Part Fields, 2014 11 26;74(11):3149.
    PMID: 25814876
    A search for heavy, right-handed neutrinos, [Formula: see text] ([Formula: see text]), and right-handed [Formula: see text] bosons, which arise in the left-right symmetric extensions of the standard model, has been performed by the CMS experiment. The search was based on a sample of two lepton plus two jet events collected in proton-proton collisions at a center-of-mass energy of 8[Formula: see text] corresponding to an integrated luminosity of 19.7 [Formula: see text]. For models with strict left-right symmetry, and assuming only one [Formula: see text] flavor contributes significantly to the [Formula: see text] decay width, the region in the two-dimensional [Formula: see text] mass plane excluded at a 95 % confidence level extends to approximately [Formula: see text] and covers a large range of neutrino masses below the [Formula: see text] boson mass, depending on the value of [Formula: see text]. This search significantly extends the [Formula: see text] exclusion region beyond previous results.
  8. CMS Collaboration, Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Bergauer T, et al.
    Eur Phys J C Part Fields, 2020;80(3):189.
    PMID: 32226948 DOI: 10.1140/epjc/s10052-020-7739-7
    A search is presented for τ slepton pairs produced in proton-proton collisions at a center-of-mass energy of 13 TeV . The search is carried out in events containing two τ leptons in the final state, on the assumption that each τ slepton decays primarily to a τ lepton and a neutralino. Events are considered in which each τ lepton decays to one or more hadrons and a neutrino, or in which one of the τ leptons decays instead to an electron or a muon and two neutrinos. The data, collected with the CMS detector in 2016 and 2017, correspond to an integrated luminosity of 77.2 fb - 1 . The observed data are consistent with the standard model background expectation. The results are used to set 95% confidence level upper limits on the cross section for τ slepton pair production in various models for τ slepton masses between 90 and 200 GeV and neutralino masses of 1, 10, and 20 GeV . In the case of purely left-handed τ slepton production and decay to a τ lepton and a neutralino with a mass of 1 GeV , the strongest limit is obtained for a τ slepton mass of 125 GeV at a factor of 1.14 larger than the theoretical cross section.
  9. He L, Mao Y, Zhang L, Wang H, Alias SA, Gao B, et al.
    BMC Biotechnol, 2017 02 28;17(1):22.
    PMID: 28245836 DOI: 10.1186/s12896-017-0343-8
    BACKGROUND: α-Amylase plays a pivotal role in a broad range of industrial processes. To meet increasing demands of biocatalytic tasks, considerable efforts have been made to isolate enzymes produced by extremophiles. However, the relevant data of α-amylases from cold-adapted fungi are still insufficient. In addition, bread quality presents a particular interest due to its high consummation. Thus developing amylases to improve textural properties could combine health benefits with good sensory properties. Furthermore, iron oxide nanoparticles provide an economical and convenient method for separation of biomacromolecules. In order to maximize the catalytic efficiency of α-amylase and support further applications, a comprehensive characterization of magnetic immobilization of α-amylase is crucial and needed.

    RESULTS: A novel α-amylase (AmyA1) containing an open reading frame of 1482 bp was cloned from Antarctic psychrotolerant fungus G. pannorum and then expressed in the newly constructed Aspergillus oryzae system. The purified recombinant AmyA1 was approximate 52 kDa. AmyA1 was optimally active at pH 5.0 and 40 °C, and retained over 20% of maximal activity at 0-20 °C. The K m and V max values toward soluble starch were 2.51 mg/mL and 8.24 × 10-2 mg/(mL min) respectively, with specific activity of 12.8 × 103 U/mg. AmyA1 presented broad substrate specificity, and the main hydrolysis products were glucose, maltose, and maltotetraose. The influence of AmyA1 on the quality of bread was further investigated. The application study shows a 26% increase in specific volume, 14.5% increase in cohesiveness and 14.1% decrease in gumminess in comparison with the control. AmyA1 was immobilized on magnetic nanoparticles and characterized. The immobilized enzyme showed improved thermostability and enhanced pH tolerance under neutral conditions. Also, magnetically immobilized AmyA1 can be easily recovered and reused for maximum utilization.

    CONCLUSIONS: A novel α-amylase (AmyA1) from Antarctic psychrotolerant fungus was cloned, heterologous expression in Aspergillus oryzae, and characterized. The detailed report of the enzymatic properties of AmyA1 gives new insights into fungal cold-adapted amylase. Application study showed potential value of AmyA1 in the food and starch fields. In addition, AmyA1 was immobilized on magnetic nanoparticles and characterized. The improved stability and longer service life of AmyA1 could potentially benefit industrial applications.

  10. CMS Collaboration, Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Bergauer T, et al.
    Eur Phys J C Part Fields, 2021;81(7):629.
    PMID: 34727144 DOI: 10.1140/epjc/s10052-021-09236-z
    Results of the Model Unspecific Search in CMS (MUSiC), using proton-proton collision data recorded at the LHC at a centre-of-mass energy of 13 TeV , corresponding to an integrated luminosity of 35.9 fb - 1 , are presented. The MUSiC analysis searches for anomalies that could be signatures of physics beyond the standard model. The analysis is based on the comparison of observed data with the standard model prediction, as determined from simulation, in several hundred final states and multiple kinematic distributions. Events containing at least one electron or muon are classified based on their final state topology, and an automated search algorithm surveys the observed data for deviations from the prediction. The sensitivity of the search is validated using multiple methods. No significant deviations from the predictions have been observed. For a wide range of final state topologies, agreement is found between the data and the standard model simulation. This analysis complements dedicated search analyses by significantly expanding the range of final states covered using a model independent approach with the largest data set to date to probe phase space regions beyond the reach of previous general searches.
  11. Sirunyan AM, CMS Collaboration, Tumasyan A, Adam W, Bergauer T, Dragicevic M, et al.
    Eur Phys J C Part Fields, 2021;81(1):13.
    PMID: 33493254 DOI: 10.1140/epjc/s10052-020-08739-5
    A search for dark matter particles is performed using events with a Z boson candidate and large missing transverse momentum. The analysis is based on proton-proton collision data at a center-of-mass energy of 13 Te , collected by the CMS experiment at the LHC in 2016-2018, corresponding to an integrated luminosity of 137 fb - 1 . The search uses the decay channels Z → e e and Z → μ μ . No significant excess of events is observed over the background expected from the standard model. Limits are set on dark matter particle production in the context of simplified models with vector, axial-vector, scalar, and pseudoscalar mediators, as well as on a two-Higgs-doublet model with an additional pseudoscalar mediator. In addition, limits are provided for spin-dependent and spin-independent scattering cross sections and are compared to those from direct-detection experiments. The results are also interpreted in the context of models of invisible Higgs boson decays, unparticles, and large extra dimensions.
  12. CMS Collaboration, Sirunyan AM, Tumasyan A, Adam W, Andrejkovic JW, Bergauer T, et al.
    Eur Phys J C Part Fields, 2021;81(6):488.
    PMID: 34727143 DOI: 10.1140/epjc/s10052-021-09200-x
    Production cross sections of the Higgs boson are measured in the H → Z Z → 4 ℓ ( ℓ = e , μ ) decay channel. A data sample of proton-proton collisions at a center-of-mass energy of 13 TeV , collected by the CMS detector at the LHC and corresponding to an integrated luminosity of 137 fb - 1 is used. The signal strength modifier μ , defined as the ratio of the Higgs boson production rate in the 4 ℓ channel to the standard model (SM) expectation, is measured to be μ = 0.94 ± 0.07 (stat) - 0.08 + 0.09 (syst) at a fixed value of m H = 125.38 GeV . The signal strength modifiers for the individual Higgs boson production modes are also reported. The inclusive fiducial cross section for the H → 4 ℓ process is measured to be 2 . 84 - 0.22 + 0.23 (stat) - 0.21 + 0.26 (syst) fb , which is compatible with the SM prediction of 2.84 ± 0.15 fb for the same fiducial region. Differential cross sections as a function of the transverse momentum and rapidity of the Higgs boson, the number of associated jets, and the transverse momentum of the leading associated jet are measured. A new set of cross section measurements in mutually exclusive categories targeted to identify production mechanisms and kinematical features of the events is presented. The results are in agreement with the SM predictions.
  13. Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Asilar E, Bergauer T, et al.
    Eur Phys J C Part Fields, 2018;78(11):965.
    PMID: 30881214 DOI: 10.1140/epjc/s10052-018-6373-0
    The production of a Z boson, decaying to two charged leptons, in association with jets in proton-proton collisions at a centre-of-mass energy of 13 TeV is measured. Data recorded with the CMS detector at the LHC are used that correspond to an integrated luminosity of 2.19 fb -1 . The cross section is measured as a function of the jet multiplicity and its dependence on the transverse momentum of the Z boson, the jet kinematic variables (transverse momentum and rapidity), the scalar sum of the jet momenta, which quantifies the hadronic activity, and the balance in transverse momentum between the reconstructed jet recoil and the Z boson. The measurements are compared with predictions from four different calculations. The first two merge matrix elements with different parton multiplicities in the final state and parton showering, one of which includes one-loop corrections. The third is a fixed-order calculation with next-to-next-to-leading order accuracy for the process with a Z boson and one parton in the final state. The fourth combines the fully differential next-to-next-to-leading order calculation of the process with no parton in the final state with next-to-next-to-leading logarithm resummation and parton showering.
  14. Chen C, Jamiat N, Mao Y
    Front Psychol, 2023;14:1236297.
    PMID: 37599782 DOI: 10.3389/fpsyg.2023.1236297
    Existing empirical research has demonstrated the positive effects of flipping the classroom to improve student motivation and achievement by flipping in-class learning content to pre-class. However, the flipped classroom approach requires that students be engaged and motivated in the pre-class stage to ensure that the in-class learning activities run smoothly. Previous studies have highlighted the difficulties that students often encounter when trying to learn Chinese characters in Chinese language classes, especially those who are in the early stages of learning the language. Therefore, in this study, a gamified interactive e-book was developed and used in a flipped classroom for Chinese character learning. To evaluate the effectiveness of this approach, a pre-test and post-test control group experimental design was used. The participants were 90 s-grade students from a public primary school in Zhengzhou, China, who were randomly assigned to two experimental groups and one control group: the students who used a gamified interactive e-book in a Chinese character learning flipped classroom (GIEFC group), the students who used a traditional flipped classroom (TFC group), and the students who used a traditional teaching classroom (TTC group). The experimental results indicated that students in the GIEFC group scored higher than those in the TFC and TTC groups in terms of learning achievements and motivation. In addition, the experimental results also demonstrated the positive effects of gamified interactive e-books in flipped classroom learning. Future research could explore a variety of different types of game elements as well as the extension of research to other subjects.
  15. Wei L, Lim SG, Xie Q, Văn KN, Piratvisuth T, Huang Y, et al.
    Lancet Gastroenterol Hepatol, 2019 02;4(2):127-134.
    PMID: 30555048 DOI: 10.1016/S2468-1253(18)30343-1
    BACKGROUND: Treatment with combined sofosbuvir and velpatasvir has resulted in high sustained virological response rates in patients chronically infected with hepatitis C virus (HCV) with genotypes 1-6 in clinical trials and real-world settings, but its efficacy and safety has not been assessed in Asia, a region with diverse HCV genotypes.

    METHODS: In this single-arm, open-label, phase 3 trial, we recruited patients from 38 sites across China, Thailand, Vietnam, Singapore, and Malaysia, who were chronically infected with HCV genotypes 1-6, and were HCV treatment-naive or treatment-experienced, either without cirrhosis or with compensated cirrhosis. Patients self-administered a combined sofosbuvir (400 mg) and velpatasvir (100 mg) tablet once daily for 12 weeks. The primary efficacy endpoint was sustained virological response, defined as HCV RNA less than 15 IU/mL at 12 weeks after completion of treatment (SVR12), assessed in all patients who received at least one dose of study drug. The primary safety endpoint was the proportion of adverse events leading to premature discontinuation of study drug. This trial is registered with ClinicalTrials.gov, number NCT02671500, and is completed.

    FINDINGS: Between April 14, 2016, and June 30, 2017, 375 patients were enrolled in the study, of whom 374 completed the full treatment course and one discontinued treatment. Overall, 362 (97% [95% CI 94-98]) of 375 patients achieved SVR12. Among 42 patients with HCV genotype 3b, all of whom had baseline resistance-associated substitutions in NS5A, 25 (89% [95% CI 72-98]) of 28 patients without cirrhosis and seven (50% [23-77]) of 14 patients with cirrhosis achieved SVR12. The most common adverse events were upper respiratory tract infection (36 [10%] patients) and headache (18 [5%] patients). There were no discontinuations due to adverse events. Serious adverse events were reported in three (1%) patients, none of which was judged to be related to sofosbuvir-velpatasvir treatment.

    INTERPRETATION: Consistent with data from other phase 3 studies, single-tablet sofosbuvir-velpatasvir for 12 weeks is an efficacious and safe treatment for Asian patients with chronic HCV infection, but might have lower efficacy in those infected with HCV genotype 3b and with cirrhosis.

    FUNDING: Gilead Sciences.

  16. Qin S, Chen Z, Fang W, Ren Z, Xu R, Ryoo BY, et al.
    J Clin Oncol, 2023 Mar 01;41(7):1434-1443.
    PMID: 36455168 DOI: 10.1200/JCO.22.00620
    PURPOSE: We evaluated the efficacy and safety of pembrolizumab in patients from Asia with previously treated advanced hepatocellular carcinoma (HCC).

    METHODS: In a double-blind, phase III trial, 453 patients with advanced HCC and progression during or after treatment with or intolerance to sorafenib or oxaliplatin-based chemotherapy were randomly assigned in a 2:1 ratio to receive pembrolizumab (200 mg) or placebo once every 3 weeks for ≤ 35 cycles plus best supportive care. The primary end point was overall survival (one-sided significance threshold, P = .0193 [final analysis]). Secondary end points included progression-free survival (PFS) and objective response rate (ORR; one-sided significance threshold, P = .0134 and .0091, respectively [second interim analysis]; RECIST version 1.1, by blinded independent central review).

    RESULTS: Median overall survival was longer in the pembrolizumab group than in the placebo group (14.6 v 13.0 months; hazard ratio for death, 0.79; 95% CI, 0.63 to 0.99; P = .0180). Median PFS was also longer in the pembrolizumab group than in the placebo group (2.6 v 2.3 months; hazard ratio for progression or death, 0.74; 95% CI, 0.60 to 0.92; P = .0032). ORR was greater in the pembrolizumab group (12.7% [95% CI, 9.1 to 17.0]) than in the placebo group (1.3% [95% CI, 0.2 to 4.6]; P < .0001). Treatment-related adverse events occurred in 66.9% of patients (grade 3, 12.0%; grade 4, 1.3%; grade 5, 1.0%) in the pembrolizumab group and 49.7% of patients (grade 3, 5.9%; grade 4, 0%; grade 5, 0%) in the placebo group.

    CONCLUSION: In patients from Asia with previously treated advanced HCC, pembrolizumab significantly prolonged overall survival and PFS, and ORR was greater versus placebo.

  17. Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Asilar E, Bergauer T, et al.
    Eur Phys J C Part Fields, 2019;79(5):421.
    PMID: 31178657 DOI: 10.1140/epjc/s10052-019-6909-y
    Combined measurements of the production and decay rates of the Higgs boson, as well as its couplings to vector bosons and fermions, are presented. The analysis uses the LHC proton-proton collision data set recorded with the CMS detector in 2016 at s = 13 Te , corresponding to an integrated luminosity of 35.9 fb - 1 . The combination is based on analyses targeting the five main Higgs boson production mechanisms (gluon fusion, vector boson fusion, and associated production with a W or Z boson, or a top quark-antiquark pair) and the following decay modes: H → γ γ , Z Z , W W , τ τ , b b , and μ μ . Searches for invisible Higgs boson decays are also considered. The best-fit ratio of the signal yield to the standard model expectation is measured to be μ = 1.17 ± 0.10 , assuming a Higgs boson mass of 125.09 Ge . Additional results are given for various assumptions on the scaling behavior of the production and decay modes, including generic parametrizations based on ratios of cross sections and branching fractions or couplings. The results are compatible with the standard model predictions in all parametrizations considered. In addition, constraints are placed on various two Higgs doublet models.
  18. Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Bergauer T, Dragicevic M, et al.
    Eur Phys J C Part Fields, 2015 10 29;75(10):511.
    PMID: 26549982
    Measurements of the [Formula: see text][Formula: see text] production cross sections in proton-proton collisions at center-of-mass energies of 7 and 8[Formula: see text] are presented. Candidate events for the leptonic decay mode [Formula: see text], where [Formula: see text] denotes an electron or a muon, are reconstructed and selected from data corresponding to an integrated luminosity of 5.1 (19.6)[Formula: see text] at 7 (8)[Formula: see text] collected with the CMS experiment. The measured cross sections, [Formula: see text] at 7[Formula: see text], and [Formula: see text] at 8[Formula: see text], are in good agreement with the standard model predictions with next-to-leading-order accuracy. The selected data are analyzed to search for anomalous triple gauge couplings involving the [Formula: see text][Formula: see text] final state. In the absence of any deviation from the standard model predictions, limits are set on the relevant parameters. These limits are then combined with the previously published CMS results for [Formula: see text][Formula: see text] in 4[Formula: see text] final states, yielding the most stringent constraints on the anomalous couplings.
  19. Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Asilar E, Bergauer T, et al.
    Eur Phys J C Part Fields, 2016;76(8):460.
    PMID: 28747851 DOI: 10.1140/epjc/s10052-016-4292-5
    Results are reported from a search for the pair production of top squarks, the supersymmetric partners of top quarks, in final states with jets and missing transverse momentum. The data sample used in this search was collected by the CMS detector and corresponds to an integrated luminosity of 18.9[Formula: see text] of proton-proton collisions at a centre-of-mass energy of 8[Formula: see text] produced by the LHC. The search features novel background suppression and prediction methods, including a dedicated top quark pair reconstruction algorithm. The data are found to be in agreement with the predicted backgrounds. Exclusion limits are set in simplified supersymmetry models with the top squark decaying to jets and an undetected neutralino, either through a top quark or through a bottom quark and chargino. Models with the top squark decaying via a top quark are excluded for top squark masses up to 755[Formula: see text] in the case of neutralino masses below 200[Formula: see text]. For decays via a chargino, top squark masses up to 620[Formula: see text] are excluded, depending on the masses of the chargino and neutralino.
  20. Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Asilar E, Bergauer T, et al.
    Eur Phys J C Part Fields, 2016;76(6):317.
    PMID: 28775662 DOI: 10.1140/epjc/s10052-016-4149-y
    A search for narrow resonances decaying to an electron and a muon is presented. The [Formula: see text] [Formula: see text] mass spectrum is also investigated for non-resonant contributions from the production of quantum black holes (QBHs). The analysis is performed using data corresponding to an integrated luminosity of 19.7[Formula: see text] collected in proton-proton collisions at a centre-of-mass energy of 8[Formula: see text] with the CMS detector at the LHC. With no evidence for physics beyond the standard model in the invariant mass spectrum of selected [Formula: see text] pairs, upper limits are set at 95 [Formula: see text] confidence level on the product of cross section and branching fraction for signals arising in theories with charged lepton flavour violation. In the search for narrow resonances, the resonant production of a [Formula: see text] sneutrino in R-parity violating supersymmetry is considered. The [Formula: see text] sneutrino is excluded for masses below 1.28[Formula: see text] for couplings [Formula: see text], and below 2.30[Formula: see text] for [Formula: see text] and [Formula: see text]. These are the most stringent limits to date from direct searches at high-energy colliders. In addition, the resonance searches are interpreted in terms of a model with heavy partners of the [Formula: see text] boson and the photon. In a framework of TeV-scale quantum gravity based on a renormalization of Newton's constant, the search for non-resonant contributions to the [Formula: see text] [Formula: see text] mass spectrum excludes QBH production below a threshold mass [Formula: see text] of 1.99[Formula: see text]. In models that invoke extra dimensions, the bounds range from 2.36[Formula: see text] for one extra dimension to 3.63[Formula: see text] for six extra dimensions. This is the first search for QBHs decaying into the [Formula: see text] [Formula: see text] final state.
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