Displaying publications 1 - 20 of 239 in total

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  1. Wong SSM, Wong KPL, Angus MIL, Chen Y, Choo CSC, Nah SA
    Pediatr. Surg. Int., 2020 Feb;36(2):227-233.
    PMID: 31654110 DOI: 10.1007/s00383-019-04592-0
    PURPOSE: Little is known of how children seek health information. This study evaluates online health information (OHI) seeking behaviours in adolescents undergoing major elective surgical procedures and compares responses within parent-child dyads.

    METHODS: With institutional approval, we prospectively surveyed parents of children admitted to our institution for major elective operations between November 2017 and November 2018, using convenience sampling. Patients aged 12 years and above were also invited. Each respondent completed an anonymized modification of a previously published survey on Internet usage. Chi squared tests were used for categorical data, with significance at P value 

  2. Su H, Kanchanatip E, Wang D, Zheng R, Huang Z, Chen Y, et al.
    Waste Manag, 2020 Feb 01;102:520-527.
    PMID: 31765972 DOI: 10.1016/j.wasman.2019.11.018
    In China, waste sorting practice is not strictly followed, plastics, especially food packaging, are commonly mixed in food waste. Supercritical water gasification (SCWG) of unsorted food waste was conducted in this study, using model unsorted food waste by mixture of pure food waste and plastic. Different operating parameters including reaction temperature, residence time, and feedstock concentration were investigated. Moreover, the effect of three representative food additives namely NaCl, NaHCO3 and Na2CO3 were tested in this work. Finally, comparative analysis about SCWG of unsorted food waste, pure food waste, and plastic was studied. It was found that higher reaction temperature, longer residence time and lower feedstock concentration were advantageous for SCWG of unsorted food waste. Within the range of operating parameters in this study, when the feedstock concentration was 5 wt%, the highest H2 yield (7.69 mol/kg), H2 selectivity (82.11%), total gas yield (17.05 mol/kg), and efficiencies of SCWG (cold gas efficiency, gasification efficiency, carbon gasification efficiency, and hydrogen gasification efficiency) were obtained at 480 °C for 75 min. Also, the addition of food additives with Na+ promoted the SCWG of unsorted food waste. The Na2CO3 showed the best catalytic performance on enhancement of H2 and syngas production. This research demonstrated the positive effect of waste sorting on the SCWG of food waste, and provided novel results and information that help to overcome the problems in the process of food waste treatment and accelerate the industrial application of SCWG technology in the future.
  3. Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Bergauer T, Brandstetter J, et al.
    Phys. Rev. Lett., 2020 Jan 31;124(4):041803.
    PMID: 32058742 DOI: 10.1103/PhysRevLett.124.041803
    The first search for supersymmetry in events with an experimental signature of one soft, hadronically decaying τ lepton, one energetic jet from initial-state radiation, and large transverse momentum imbalance is presented. These event signatures are consistent with direct or indirect production of scalar τ leptons (τ[over ˜]) in supersymmetric models that exhibit coannihilation between the τ[over ˜] and the lightest neutralino (χ[over ˜]_{1}^{0}), and that could generate the observed relic density of dark matter. The data correspond to an integrated luminosity of 77.2  fb^{-1} of proton-proton collisions at sqrt[s]=13  TeV collected with the CMS detector at the LHC in 2016 and 2017. The results are interpreted in a supersymmetric scenario with a small mass difference (Δm) between the chargino (χ[over ˜]_{1}^{±}) or next-to-lightest neutralino (χ[over ˜]_{2}^{0}), and the χ[over ˜]_{1}^{0}. The mass of the τ[over ˜] is assumed to be the average of the χ[over ˜]_{1}^{±} and χ[over ˜]_{1}^{0} masses. The data are consistent with standard model background predictions. Upper limits at 95% confidence level are set on the sum of the χ[over ˜]_{1}^{±}, χ[over ˜]_{2}^{0}, and τ[over ˜] production cross sections for Δm(χ[over ˜]_{1}^{±},χ[over ˜]_{1}^{0})=50  GeV, resulting in a lower limit of 290 GeV on the mass of the χ[over ˜]_{1}^{±}, which is the most stringent to date and surpasses the bounds from the LEP experiments.
  4. Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Asilar E, Bergauer T, et al.
    Eur Phys J C Part Fields, 2020;80(1):43.
    PMID: 32026888 DOI: 10.1140/epjc/s10052-019-7585-7
    A measurement is presented of electroweak (EW) production of a
    W
    boson in association with two jets in proton-proton collisions at


    s

    =
    13


    Te



    . The data sample was recorded by the CMS Collaboration at the LHC and corresponds to an integrated luminosity of 35.9



    fb

    -
    1



    . The measurement is performed for the


    ν

    jj final state (with


    ν

    indicating a lepton-neutrino pair, and j representing the quarks produced in the hard interaction) in a kinematic region defined by invariant mass


    m
    jj

    >
    120


    Ge



    and transverse momenta


    p

    T
    j


    >
    25


    Ge



    . The cross section of the process is measured in the electron and muon channels yielding


    σ
    EW


    (
    W
    jj
    )

    =
    6.23
    ±
    0.12

    (stat)
    ±
    0.61

    (syst)

    pb

    per channel, in agreement with leading-order standard model predictions. The additional hadronic activity of events in a signal-enriched region is studied, and the measurements are compared with predictions. The final state is also used to perform a search for anomalous trilinear gauge couplings. Limits on anomalous trilinear gauge couplings associated with dimension-six operators are given in the framework of an effective field theory. The corresponding 95% confidence level intervals are

    -
    2.3
    <

    c

    W
    W
    W


    /

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    2

    <
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    Te



    -
    2



    ,

    -
    8.8
    <

    c
    W

    /

    Λ
    2

    <
    16



    Te



    -
    2



    , and

    -
    45
    <

    c
    B

    /

    Λ
    2

    <
    46



    Te



    -
    2



    . These results are combined with the CMS EW
    Zjj
    analysis, yielding the constraint on the

    c

    W
    W
    W


    coupling:

    -
    1.8
    <

    c

    W
    W
    W


    /

    Λ
    2

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    .
  5. Lin J, Gopinath SCB, Lakshmipriya T, Chen Y, Yuan WR, Yang M
    Int. J. Biol. Macromol., 2019 Dec 01;141:564-569.
    PMID: 31493451 DOI: 10.1016/j.ijbiomac.2019.09.012
    Human papilloma virus (HPV) affects predominantly the genital area, which includes vagina, cervix, penis, vulva scrotum, rectum and anus. Among 100 types of HPV, 14 types are considered to cause the risky cancer. The gene HPV-16 E7 is responsible for the development of cancer with the infected women. Earlier identification of this gene sequence avoids the cancer progression. The targeted HPV-16 E7 sequence was sandwiched by capture and reporter sequences on the carbodiimidazole-modified interdigitated electrode (IDE) surface. Target sequence at 100 f. was paired to the capture sequence immobilized on IDE sensing surface. To this surface, different concentrations of reporter sequence with and without gold rod (GNR) were evaluated. In both cases the detections were attained 1 aM by the reporter sequence pairing and with GNR increments in current were found. This enhancement was found to be 1000 folds, considering the condition was revealed in the absence of reporter. This sandwich detection strategy of capture-target-reporter sequences for HPV-16 detection on the IDE sensing surface helps to diagnose the association of cervical cancer.
  6. Chen T, Yang Z, Choudhury AK, Al Mahtab M, Li J, Chen Y, et al.
    Hepatol Int, 2019 Nov;13(6):695-705.
    PMID: 31650510 DOI: 10.1007/s12072-019-09992-x
    BACKGROUND AND AIM: Cirrhosis is a controversial determinant of mortality in HBV-related acute-on-chronic liver failure (HBV-ACLF). The present study aimed to explore the effects of cirrhosis and the associated risk factors, especially its complications, on the outcome of HBV-ACLF.

    METHODS: A prospective-retrospective cohort of 985 patients was identified from the APASL-ACLF Research Consortium (AARC) database and the Chinese Study Group. Complications of ACLF (ascites, infection, hepatorenal syndrome, hepatic encephalopathy, upper gastrointestinal bleeding) as well as cirrhosis and the current main prognostic models were measured for their predictive ability for 28- or 90-day mortality.

    RESULTS: A total of 709 patients with HBV-ACLF as defined by the AARC criteria were enrolled. Among these HBV-ACLF patients, the cirrhotic group showed significantly higher mortality and complications than the non-cirrhotic group. A total of 36.1% and 40.1% of patients met the European Association for the Study of Liver (EASL)-Chronic Liver Failure consortium (CLIF-C) criteria in the non-cirrhotic and cirrhotic groups, respectively; these patients had significantly higher rates of mortality and complications than those who did not satisfy the CLIF-C criteria. Furthermore, among patients who did not meet the CLIF-C criteria, the cirrhotic group exhibited higher mortality and complication rates than the non-cirrhotic group, without significant differences in organ failure. The Tongji prognostic predictor model score (TPPMs), which set the number of complications as one of the determinants, showed comparable or superior ability to the Chinese Group on the Study of Severe Hepatitis B-ACLF score (COSSH-ACLFs), APASL-ACLF Research Consortium score (AARC-ACLFs), CLIF-C organ failure score (CLIF-C OFs), CLIF-C-ACLF score (CLIF-C-ACLFs), Model for End-Stage Liver Disease score (MELDs) and MELD-sodium score (MELD-Nas) in HBV-ACLF patients, especially in cirrhotic HBV--ACLF patients. Patients with two (OR 4.70, 1.88) or three (OR 8.27, 2.65) complications had a significantly higher risk of 28- or 90-day mortality, respectively.

    CONCLUSION: The presence of complications is a major risk factor for mortality in HBV-ACLF patients. TPPM possesses high predictive ability in HBV-ACLF patients, especially in cirrhotic HBV-ACLF patients.

  7. Chen Y, Tang WY, Tong X, Ji H
    Cancer Commun (Lond), 2019 10 01;39(1):53.
    PMID: 31570104 DOI: 10.1186/s40880-019-0402-8
    Despite the tremendous efforts for improving therapeutics of lung cancer patients, its prognosis remains disappointing. This can be largely attributed to the lack of comprehensive understanding of drug resistance leading to insufficient development of effective therapeutics in clinic. Based on the current progresses of lung cancer research, we classify drug resistance mechanisms into three different levels: molecular, cellular and pathological level. All these three levels have significantly contributed to the acquisition and evolution of drug resistance in clinic. Our understanding on drug resistance mechanisms has begun to change the way of clinical practice and improve patient prognosis. In this review, we focus on discussing the pathological changes linking to drug resistance as this has been largely overlooked in the past decades.
  8. Wang Z, Li P, Ma K, Chen Y, Penfold J, Thomas RK, et al.
    J Colloid Interface Sci, 2019 Sep 05;557:124-134.
    PMID: 31518834 DOI: 10.1016/j.jcis.2019.09.016
    The ester sulfonate anionic surfactants are a potentially valuable class of sustainable surfactants. The micellar growth, associated rheological changes, and the onset of precipitation are important consequences of the addition of electrolyte and especially multi-valent electrolytes in anionic surfactants. Small angle neutron scattering, SANS, has been used to investigate the self-assembly and the impact of different valence electrolytes on the self-assembly of a range of ester sulfonate surfactants with subtly different molecular structures. The results show that in the absence of electrolyte small globular micelles form, and in the presence of NaCl, and AlCl3 relatively modest micellar growth occurs before the onset of precipitation. The micellar growth is more pronounced for the longer unbranched and branched alkyl chain lengths. Whereas changing the headgroup geometry from methyl ester to ethyl ester has in general a less profound impact. The study highlights the importance of relative counterion binding strengths and shows how the surfactant structure affects the counterion binding and hence the micelle structure. The results have important consequences for the response of such surfactants to different operational environments.
  9. Shi W, Louzada S, Grigorova M, Massaia A, Arciero E, Kibena L, et al.
    Hum. Mol. Genet., 2019 Aug 15;28(16):2785-2798.
    PMID: 31108506 DOI: 10.1093/hmg/ddz101
    Human RBMY1 genes are located in four variable-sized clusters on the Y chromosome, expressed in male germ cells and possibly associated with sperm motility. We have re-investigated the mutational background and evolutionary history of the RBMY1 copy number distribution in worldwide samples and its relevance to sperm parameters in an Estonian cohort of idiopathic male factor infertility subjects. We estimated approximate RBMY1 copy numbers in 1218 1000 Genomes Project phase 3 males from sequencing read-depth, then chose 14 for valid ation by multicolour fibre-FISH. These fibre-FISH samples provided accurate calibration standards for the entire panel and led to detailed insights into population variation and mutational mechanisms. RBMY1 copy number worldwide ranged from 3 to 13 with a mode of 8. The two larger proximal clusters were the most variable, and additional duplications, deletions and inversions were detected. Placing the copy number estimates onto the published Y-SNP-based phylogeny of the same samples suggested a minimum of 562 mutational changes, translating to a mutation rate of 2.20 × 10-3 (95% CI 1.94 × 10-3 to 2.48 × 10-3) per father-to-son Y-transmission, higher than many short tandem repeat (Y-STRs), and showed no evidence for selection for increased or decreased copy number, but possible copy number stabilizing selection. An analysis of RBMY1 copy numbers among 376 infertility subjects failed to replicate a previously reported association with sperm motility and showed no significant effect on sperm count and concentration, serum follicle stimulating hormone (FSH), luteinizing hormone (LH) and testosterone levels or testicular and semen volume. These results provide the first in-depth insights into the structural rearrangements underlying RBMY1 copy number variation across diverse human lineages.
  10. Anand L, Choudhury A, Bihari C, Sharma BC, Kumar M, Maiwall R, et al.
    Hepatology, 2019 Aug;70(2):587-596.
    PMID: 30113706 DOI: 10.1002/hep.30205
    Autoimmune hepatitis (AIH) is considered less common in the Asia Pacific region. Due to this, AIH flare as a cause of acute on chronic liver failure (ACLF) is often overlooked and treatment delayed. We aimed at the defining clinical and histopathological spectrum and role of steroid therapy in AIH-ACLF. Patients with AIH-ACLF, prospectively recruited and followed between 2012 and 2017, were analyzed from the Asian Pacific Association for the Study of the Liver ACLF Research Consortium (AARC) data base. Diagnosis of AIH was confirmed using International Autoimmune Hepatitis Group score or simplified AIH score with histopathological evidence. Of 2,825 ACLF patients, 82 (2.9%) fulfilled criteria of AIH (age 42.1 ± 18.1 years, 70% female). At baseline, mean bilirubin was 18.6 ± 8.2 mg/dL, Child-Turcotte-Pugh score was 11.7 ± 1.4, and Model for End-Stage Liver Disease (MELD) score was 27.6 ± 6.5. Mean immunoglobulin G was 21.61 ± 7.32 g/dL, and this was elevated ≥1.1 times in 97% of cases; 49% were seronegative. Liver histology was available in 90%, with median histological activity index of 10 (interquartile range, 7-12); 90% with moderate to severe interface activity; 56% showing significant parenchymal necrosis (bridging and confluent necrosis); and cirrhosis in 42%. Twenty-eight (34%) patients received steroid therapy and showed shorter intensive care unit (ICU) stay (median 1.5 versus 4 days, P < 0.001) and improved 90-day survival (75% versus 48.1%, P = 0.02) with comparable incidence of sepsis (P = 0.32) compared to those who did not. Patients of advanced age, more severe liver disease (MELD >27; 83.3% sensitivity, 78.9% specificity, area under the receiver operating characteristic curve 0.86), presence of hepatic encephalopathy, and fibrosis grade ≥F3 had an unfavorable response to corticosteroid therapy. Conclusion: AIH presenting as ACLF is not uncommon in Asian patients; a low threshold for liver biopsy is needed to confirm the diagnosis as nearly half the patients are seronegative; early stratification to steroid therapy or liver transplantation (MELD >27, hepatic encephalopathy in ≥F3) would reduce ICU stay and improve outcomes.
  11. Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Asilar E, Bergauer T, et al.
    Phys. Rev. Lett., 2019 Jul 12;123(2):022001.
    PMID: 31386524 DOI: 10.1103/PhysRevLett.123.022001
    The transverse momentum spectra of D^{0} mesons from b hadron decays are measured at midrapidity (|y|<1) in pp and Pb-Pb collisions at a nucleon-nucleon center of mass energy of 5.02 TeV with the CMS detector at the LHC. The D^{0} mesons from b hadron decays are distinguished from prompt D^{0} mesons by their decay topologies. In Pb-Pb collisions, the B→D^{0} yield is found to be suppressed in the measured p_{T} range from 2 to 100  GeV/c as compared to pp collisions. The suppression is weaker than that of prompt D^{0} mesons and charged hadrons for p_{T} around 10  GeV/c. While theoretical calculations incorporating partonic energy loss in the quark-gluon plasma can successfully describe the measured B→D^{0} suppression at higher p_{T}, the data show an indication of larger suppression than the model predictions in the range of 2
  12. Lai EL, Huang WN, Chen HH, Hsu CY, Chen DY, Hsieh TY, et al.
    Lupus, 2019 Jul;28(8):945-953.
    PMID: 31177913 DOI: 10.1177/0961203319855122
    The Fracture Risk Assessment Tool (FRAX) has been used universally for the purpose of fracture risk assessment. However, the predictive capacity of FRAX for autoimmune diseases remains inconclusive. This study aimed to compare the applicability of FRAX for autoimmune disease patients. This retrospective study recruited rheumatoid arthritis (RA), systemic lupus erythematosus (SLE) and primary Sjögren syndrome (pSS) patients with bone mineral density (BMD) tests. Patients with any osteoporotic fractures were identified. Taiwan-specific FRAX with and without BMD were then calculated. In total, 802 patients (451 RA, 233 SLE and 118 pSS) were enrolled in this study. The cumulative incidences of osteoporotic fractures in the RA, SLE and pSS patients were 43.0%, 29.2% and 33.1%, respectively. For those with a previous osteoporotic fracture, T-scores were classified as low bone mass. Overall, the patients' 10-year probability of major fracture risk by FRAX without BMD was 15.8%, which then increased to 20.3% after incorporation of BMD measurement. When analyzed by disease group, the fracture risk in RA patients was accurately predicted by FRAX. In contrast, current FRAX, either with or without BMD measurement, underestimated the fracture risk both in SLE and pSS patients, even after stratification by age and glucocorticoid treatment. For pSS patients with major osteoporotic fractures, FRAX risks imputed by RA were comparable to major osteoporotic fracture risks of RA patients. Current FRAX accurately predicted fracture probability in RA patients, but not in SLE and pSS patients. RA-imputed FRAX risk scores could be used as a temporary substitute for SLE and pSS patients.
  13. Teng H, Chen Y, Lin X, Lv Q, Chai TT, Wong FC, et al.
    Food Chem. Toxicol., 2019 Jul;129:138-143.
    PMID: 31034934 DOI: 10.1016/j.fct.2019.04.043
    The aim of this study was to assess the inhibitory effects of Sonchus olearleu extract on the generation of heterocyclic amines in roasted pork patties cooked by pan-frying. All samples were cooked for two different durations (45 min and 105 min) under 200 °C and 230 °C. 2-amino-3-methylimidazo[4,5-f]quinoline (IQ), 2-ami- no-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx), 2-amino-3,4,8-trimethylimidazo[4,5-f]quinox-aline (4,8-DiMeIQx), harman, and norharman were detected and quantified. In patties cooked at 230 °C for 105 min, S. olearleu extract (0.5%) significantly inhibited the formation of IQ, harman, and norharman by 39%, 67%, and 63%, respectively. In contrast to IQ, the levels of harman and norharman were significantly reduced by the extracts tested. However, no such effects were observed for MeIQx and 4, 8-DiMeIQx. Notably, the inhibitory effect on heterocyclic amines is significantly correlated with the antioxidant potential and total phenolic content of S. olearleu extract.
  14. Kirubakari B, Chen Y, Sasidharan S
    PMID: 31113347 DOI: 10.2174/1871523018666190522112902
    BACKGROUND: Polyalthia longifolia is a popular medicinal plant and have been widely used as traditional remedy for centuries in curing of various ailments. The purpose of this study was conducted to determine the in situ antimicrobial synergistic effects between Polyalthia longifolia leaf ethyl acetate fraction (PLEAF) and ampicillin against MRSA local isolate by using modern microscopy technique.

    METHODS: Hence, the evaluation of synergistic activity of PLEAF and ampicillin against MRSA local isolate was conducted with scanning electron microscopy (SEM).

    RESULTS: The combinational effect of PLEAF fraction and ampicillin exhibited a significant antibacterial activity against MRSA. Bacterial cells observations showed invagination, impaired cell division, extensive wrinkles, cell shrinkage, appearance of rougher cell with fibrous matrix and clustered cells which confirmed synergistic effect of PLEAF and ampicillin against MRSA local isolate by SEM.

    CONCLUSION: Conclusively, the in situ SEM observation was proved the synergistic antimicrobial activity between PLEAF fraction and ampicillin to destroy the MRSA resistance bacteria which is an important aspect of PLEAF fraction to be used in the future combinational therapy.

  15. Wang Z, Li P, Ma K, Chen Y, Campana M, Penfold J, et al.
    J Colloid Interface Sci, 2019 May 15;544:293-302.
    PMID: 30861434 DOI: 10.1016/j.jcis.2019.03.011
    The transition from monolayer to multilayer adsorption at the air-water interface in the presence of multivalent counterions has been demonstrated for a limited range of anionic surfactants which exhibit increased tolerance to precipitation in the presence of multivalent counterions. Understanding the role of molecular structure in determining the transition to surface ordering is an important aspect of the phenomenon. The focus of the paper is on the alkyl ester sulfonate, AES, surfactants; a promising group of anionic surfactants, with the potential for improved performance and biocompatibility. Neutron reflectivity measurements were made in aqueous solution and in the presence of NaCl, CaCl2, MgCl2 and AlCl3, for a range of alkyl ester sulfonate surfactants, in which the headgroup and alkyl chain geometries were manipulated. In the regions of monolayer adsorption changing the AES headgroup and alkyl chain geometries results in an increased saturation adsorption and in a more gradual decrease in the adsorption at low concentrations, consistent with a greater adsorption efficiency. Changing the AES headgroup and alkyl chain geometries also results in changes in the transition from monolayer adsorption to more ordered surface structures with the addition of AlCl3 and mixed multivalent electrolytes. A more limited surface layering is observed for the ethyl ester sulfonate, EES, with a C14 alkyl chain. Replacing the C14 alkyl chain with a C18 isostearic chain results in only monolayer adsorption. The results demonstrate the role and importance of the surfactant molecular structure in determining the nature of the surface adsorption in the presence of different electrolytes, and in the tendency to form extended surface multilayer structures.
  16. He Q, Shahabi H, Shirzadi A, Li S, Chen W, Wang N, et al.
    Sci. Total Environ., 2019 May 01;663:1-15.
    PMID: 30708212 DOI: 10.1016/j.scitotenv.2019.01.329
    Landslides are major hazards for human activities often causing great damage to human lives and infrastructure. Therefore, the main aim of the present study is to evaluate and compare three machine learning algorithms (MLAs) including Naïve Bayes (NB), radial basis function (RBF) Classifier, and RBF Network for landslide susceptibility mapping (LSM) at Longhai area in China. A total of 14 landslide conditioning factors were obtained from various data sources, then the frequency ratio (FR) and support vector machine (SVM) methods were used for the correlation and selection the most important factors for modelling process, respectively. Subsequently, the resulting three models were validated and compared using some statistical metrics including area under the receiver operating characteristics (AUROC) curve, and Friedman and Wilcoxon signed-rank tests The results indicated that the RBF Classifier model had the highest goodness-of-fit and performance based on the training and validation datasets. The results concluded that the RBF Classifier model outperformed and outclassed (AUROC = 0.881), the NB (AUROC = 0.872) and the RBF Network (AUROC = 0.854) models. The obtained results pointed out that the RBF Classifier model is a promising method for spatial prediction of landslide over the world.
  17. Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Asilar E, Bergauer T, et al.
    Phys. Rev. Lett., 2019 Apr 19;122(15):152001.
    PMID: 31050516 DOI: 10.1103/PhysRevLett.122.152001
    The modification of jet shapes in Pb-Pb collisions, relative to those in pp collisions, is studied for jets associated with an isolated photon. The data were collected with the CMS detector at the LHC at a nucleon-nucleon center-of-mass energy of 5.02 TeV. Jet shapes are constructed from charged particles with track transverse momenta (p_{T}) above 1  GeV/c in annuli around the axes of jets with p_{T}^{jet}>30  GeV/c associated with an isolated photon with p_{T}^{γ}>60  GeV/c. The jet shape distributions are consistent between peripheral Pb-Pb and pp collisions, but are modified for more central Pb-Pb collisions. In these central Pb-Pb events, a larger fraction of the jet momentum is observed at larger distances from the jet axis compared to pp, reflecting the interaction between the partonic medium created in heavy ion collisions and the traversing partons.
  18. Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Asilar E, Bergauer T, et al.
    Phys. Rev. Lett., 2019 Apr 19;122(15):151802.
    PMID: 31050519 DOI: 10.1103/PhysRevLett.122.151802
    For the first time, a search for the rare decay of the W boson to three charged pions has been performed. Proton-proton collision data recorded by the CMS experiment at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 77.3  fb^{-1}, have been analyzed. No significant excess is observed above the background expectation. An upper limit of 1.01×10^{-6} is set at 95% confidence level on the branching fraction of the W boson to three charged pions. This provides a strong motivation for theoretical calculations of this branching fraction.
  19. Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Asilar E, Bergauer T, et al.
    Phys. Rev. Lett., 2019 Apr 05;122(13):132003.
    PMID: 31012605 DOI: 10.1103/PhysRevLett.122.132003
    The observation of single top quark production in association with a Z boson and a quark (tZq) is reported. Events from proton-proton collisions at a center-of-mass energy of 13 TeV containing three charged leptons (either electrons or muons) and at least two jets are analyzed. The data were collected with the CMS detector in 2016 and 2017 and correspond to an integrated luminosity of 77.4fb^{-1}. The increased integrated luminosity, a multivariate lepton identification, and a redesigned analysis strategy improve significantly the sensitivity of the analysis compared to previous searches for tZq production. The tZq signal is observed with a significance well over 5 standard deviations. The measured tZq production cross section is σ(pp→tZq→tℓ^{+}ℓ^{-}q)=111±13(stat)_{-9}^{+11}(syst)  fb, for dilepton invariant masses above 30 GeV, in agreement with the standard model expectation.
  20. Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Asilar E, Bergauer T, et al.
    Phys. Rev. Lett., 2019 Mar 29;122(12):121803.
    PMID: 30978057 DOI: 10.1103/PhysRevLett.122.121803
    This Letter describes a search for Higgs boson pair production using the combined results from four final states: bbγγ, bbττ, bbbb, and bbVV, where V represents a W or Z boson. The search is performed using data collected in 2016 by the CMS experiment from LHC proton-proton collisions at sqrt[s]=13  TeV, corresponding to an integrated luminosity of 35.9  fb^{-1}. Limits are set on the Higgs boson pair production cross section. A 95% confidence level observed (expected) upper limit on the nonresonant production cross section is set at 22.2 (12.8) times the standard model value. A search for narrow resonances decaying to Higgs boson pairs is also performed in the mass range 250-3000 GeV. No evidence for a signal is observed, and upper limits are set on the resonance production cross section.
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