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  1. Chow SK, Yap DFS, Sim JH, Tan PS, Hee NKY, Teow XM, et al.
    Med J Malaysia, 2023 Dec;78(7):907-913.
    PMID: 38159927
    INTRODUCTION: This study aimed to determine the prevalence and association between the severity of COVID-19 and short and long-term neuropsychiatric symptoms, as well as the risk factors for the development of these symptoms.

    MATERIALS AND METHODS: A prospective observational study was conducted between 1st October 2021 till September 2022 in the state of Johor, Malaysia. 300 patients with confirmed SARS-CoV-2 infection were randomly selected and followed up for six months. Data were analysed by using Chi-square test, Fisher's Exact test, Paired t test and Multiple logistic regression.

    RESULTS: The prevalence of short-term neuropsychiatric symptoms was 78%, with anosmia being the most prevalent symptom. Long-term symptoms were found in 22.75% of patients, with headache being the most prevalent (p= 0.001). COVID-19 Stage 2 and 3 infections were associated with a higher risk of short-term neuropsychiatric symptoms, OR for Stage 2 infection was 5.18 (95% CI: 1.48-16.97; p=0.009) and for Stage 3 infection was 4.52 (95% CI: 1.76-11.59; p=0.002). Complete vaccination was a significant predictor of longterm symptoms with adjusted OR 3.65 (95% CI 1.22-10.91; p=0.021).

    CONCLUSION: This study demonstrated that neuropsychiatric symptoms were common among COVID-19 patients in Johor, Malaysia and the risk of these symptoms was associated with the severity of the infection. Additionally, complete vaccination does not completely protect against long-term neuropsychiatric deficits. This is crucial for continuous monitoring and addressing neuropsychiatric symptoms in COVID-19 survivors.

  2. Tan P, Li H, Wang J, Gopinath SCB
    Biotechnol Appl Biochem, 2021 Dec;68(6):1236-1242.
    PMID: 33043496 DOI: 10.1002/bab.2045
    Recent developments in nanotechnology promoted the production of nanomaterials with various shapes and sizes by utilizing interdisciplinary researches of biology, chemistry, and material science toward the clinical perspectives. In particular, gold and silver (Ag) are noble metals that exhibit tunable and unique plasmonic properties for the downstream applications. Ag exhibits higher thermal and electrical conductivities, and more efficient in the electron transfer than gold with sharper extinction bands. In addition, modified Ag nanoparticle is more stable in water and air. With all these above features, Ag is an attractive tool in various fields, including diagnosis, drug delivery, environmental, electronics, and as antimicrobial agent. In particular, applications of Ag nanoparticle in the fields of biosensor and imaging are prominent in recent days. Enhancing the specific detection of clinical markers with Ag nanoparticle has been proved by several studies. This review discussed the constructive application of Ag nanoparticle in biosensor and bioimaging for the detection of small molecule to larger whole cell in the perspectives of diagnosing diseases.
  3. Chin HH, Chin YH, Yap YL, Tan PS, Tiong XT, Noor Hidayah Y, et al.
    Med J Malaysia, 2021 11;76(6):845-852.
    PMID: 34806671
    INTRODUCTION: COVID-19 pandemic has affected healthcare services around the globe as hospitals were turned into designated hospitals to accommodate high risk groups of patients with COVID-19 infection including end stage kidney disease (ESKD) patients. In Malaysia, there was insufficient data on COVID-19 infection among ESKD patients. This study aims to determine factors and survival outcomes associated with COVID-19 infection among ESKD patients in a designated COVID-19 hospital in Malaysia.

    METHODS AND MATERIALS: A retrospective cross-sectional study involving 80 haemodialysis (HD) patients recruited from March 2020 till March 2021. Patients' information and results was retrieved and evaluated. Risk factors affecting the COVID-19 mortality were analysed using a one-way analysis of variance (ANOVA) and binary logistic regression.

    RESULTS: The mean age of the patients was 54 years who were predominantly Malays (87.5%) and living in rural areas. Majority of them had comorbidities such as diabetes mellitus (71%) and hypertension (90%). The most common presentations were fever (46%) and cough (54%) with chest radiographs showing bilateral lower zone ground glass opacities (45%). A quarter of the study population were admitted to the intensive care unit, necessitating mechanical ventilation. This study found that 51% of the patients were given steroids and 45% required oxygen supplementation. The COVID-19 infection mortality among the study population was 12.5%. Simple logistic regression analysis showed that albumin, Odd Ratio, OR=0.85 (95% Confidence Interval, 95%CI: 0.73, 0.98)) and absolute lymphocyte count OR=0.08 (95%CI: 0.11, 0.56) have inverse association with COVID-19 mortality. C-reactive protein OR=1.02 (95%CI: 1.01, 1.04), lactate dehydrogenase OR=1.01 (95%CI: 1.00, 1.01), mechanical ventilation OR=17.21 (95%CI: 3.03, 97.67) and high dose steroids OR=15.71 (95%CI: 1.80, 137.42) were directly associated with COVID-19 mortality.

    CONCLUSION: The high mortality rate among ESKD patients receiving HD was alarming. This warrants additional infection control measures to prevent the spread of COVID- 19 infection among this vulnerable group of patients. Expediting vaccination efforts in this group of patients should be advocated to reduce the incidence of complications from COVID-19 infection.

  4. Sriram S, Kang NY, Subramanian S, Nandi T, Sudhagar S, Xing Q, et al.
    Stem Cell Res Ther, 2021 02 05;12(1):113.
    PMID: 33546754 DOI: 10.1186/s13287-021-02171-6
    BACKGROUND: Despite recent rapid progress in method development and biological understanding of induced pluripotent stem (iPS) cells, there has been a relative shortage of tools that monitor the early reprogramming process into human iPS cells.

    METHODS: We screened the in-house built fluorescent library compounds that specifically bind human iPS cells. After tertiary screening, the selected probe was analyzed for its ability to detect reprogramming cells in the time-dependent manner using high-content imaging analysis. The probe was compared with conventional dyes in different reprogramming methods, cell types, and cell culture conditions. Cell sorting was performed with the fluorescent probe to analyze the early reprogramming cells for their pluripotent characteristics and genome-wide gene expression signatures by RNA-seq. Finally, the candidate reprogramming factor identified was investigated for its ability to modulate reprogramming efficiency.

    RESULTS: We identified a novel BODIPY-derived fluorescent probe, BDL-E5, which detects live human iPS cells at the early reprogramming stage. BDL-E5 can recognize authentic reprogramming cells around 7 days before iPS colonies are formed and stained positive with conventional pluripotent markers. Cell sorting of reprogrammed cells with BDL-E5 allowed generation of an increased number and higher quality of iPS cells. RNA sequencing analysis of BDL-E5-positive versus negative cells revealed early reprogramming patterns of gene expression, which notably included CREB1. Reprogramming efficiency was significantly increased by overexpression of CREB1 and decreased by knockdown of CREB1.

    CONCLUSION: Collectively, BDL-E5 offers a valuable tool for delineating the early reprogramming pathway and clinically applicable commercial production of human iPS cells.

  5. Tan PC, Abdussyukur SA, Lim BK, Win ST, Omar SZ
    BJOG, 2020 10;127(11):1430-1437.
    PMID: 32356413 DOI: 10.1111/1471-0528.16290
    OBJECTIVE: To evaluate fasting for 12 hours compared with expedited oral feeding in hospitalised women with hyperemesis gravidarum (HG).

    DESIGN: Randomised trial.

    SETTING: University Hospital, Malaysia: April 2016-April 2017.

    POPULATION: One hundred and sixty women hospitalised for HG.

    METHOD: Women were randomised upon admission to fasting for 12 hours or expedited oral feeding. Standard HG care was instituted.

    MAIN OUTCOME MEASURE: Primary outcome was satisfaction score with overall treatment at 24 hours (0-10 Visual Numerical Rating Scale VNRS), vomiting episodes within 24 hours and nausea VNRS score at enrolment, and at 8, 16 and 24 hours.

    RESULTS: Satisfaction score, median (interquartile range) 8 (5-9) versus 8 (7-9) (P = 0.08) and 24-hour vomiting episodes were 1 (0-4) versus 1 (0-5) (P = 0.24) for 12-hour fasting versus expedited feeding, respectively. Repeated measures analysis of variance of nausea scores over 24 hours showed no difference (P = 0.11) between trial arms. Participants randomised to 12-hour fasting compared with expedited feeding were less likely to prefer their feeding regimen in future hospitalisation (41% versus 65%, P = 0.001), to recommend to a friend (65% versus 84%, P = 0.01; RR 0.8, 95% CI 0.6-0.9) and to adhere to protocol (85% versus 95%, P = 0.04; RR 0.9, 95% CI 0.8-1.0). Symptoms profile, ketonuria status at 24 hours and length of hospital stay were not different.

    CONCLUSION: Advisory of 12-hour fasting compared with immediate oral feeding resulted in a non-significant difference in satisfaction score but adherence to protocol and fidelity to and recommendation of immediate oral feeding to a friend were lower. The 24-hour nausea scores and vomiting episodes were similar.

    TWEETABLE ABSTRACT: Women hospitalised for hyperemesis gravidarum could feed as soon, as much and as often as can be tolerated compared with initial fasting.

  6. Tan PS, Akhavan Farid A, Karimzadeh A, Rahimian Koloor SS, Petrů M
    Materials (Basel), 2020 Sep 21;13(18).
    PMID: 32967330 DOI: 10.3390/ma13184199
    The curvature correction factor is an important parameter in the stress calculation formulation of a helical extension spring, which describes the effect of spring wire curvature on the stress increase towards its inner radius. In this study, the parameters affecting the curvature correction factor were investigated through theoretical and numerical methods. Several finite element (FE) models of an extension spring were generated to obtain the distribution of the tensile stress in the spring. In this investigation, the hook orientation and the number of coils of the extension spring showed significant effects on the curvature correction factor. These parameters were not considered in the theoretical model for the calculation of the curvature correction factor, causing a deviation between the results of the FE model and the theoretical approach. A set of equations is proposed for the curvature correction factor, which relates both the spring index and the number of coils. These equations can be applied directly to the design of extension springs with a higher safety factor.
  7. Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Asilar E, Bergauer T, et al.
    Phys Rev Lett, 2020 Sep 04;125(10):102001.
    PMID: 32955327 DOI: 10.1103/PhysRevLett.125.102001
    The first study of charm quark diffusion with respect to the jet axis in heavy ion collisions is presented. The measurement is performed using jets with p_{T}^{jet}>60  GeV/c and D^{0} mesons with p_{T}^{D}>4  GeV/c in lead-lead (Pb-Pb) and proton-proton (pp) collisions at a nucleon-nucleon center-of-mass energy of sqrt[s_{NN}]=5.02  TeV, recorded by the CMS detector at the LHC. The radial distribution of D^{0} mesons with respect to the jet axis is sensitive to the production mechanisms of the meson, as well as to the energy loss and diffusion processes undergone by its parent parton inside the strongly interacting medium produced in Pb-Pb collisions. When compared to Monte Carlo event generators, the radial distribution in pp collisions is found to be well described by pythia, while the slope of the distribution predicted by sherpa is steeper than that of the data. In Pb-Pb collisions, compared to the pp results, the D^{0} meson distribution for 4
  8. Tan PC, Rohani E, Lim M, Win ST, Omar SZ
    BJOG, 2020 09;127(10):1250-1258.
    PMID: 32202035 DOI: 10.1111/1471-0528.16228
    OBJECTIVE: To evaluate the superficial surgical site infection (SSI) rate to 28 days and patient satisfaction with wound coverage management when their transverse suprapubic caesarean wound is left exposed compared with dressed after skin closure.

    DESIGN: Randomised trial.

    SETTING: University Hospital, Malaysia: April 2016-October 2016.

    POPULATION: 331 women delivered by caesarean section.

    METHOD: Participants were randomised to leaving their wound entirely exposed (n = 165) or dressed (n = 166) with a low adhesive dressing (next day removal).

    MAIN OUTCOME MEASURES: Primary outcomes were superficial SSI rate (assessed by provider inspection up to hospital discharge and telephone questionnaires on days 14 and 28) and patient satisfaction with wound coverage management before hospital discharge.

    RESULTS: The superficial SSI rates were 2/153 (1.3%) versus 5/157 (3.2%) (relative risk [RR] 0.4, 95% CI 0.1-2.1; P = 0.45) and patient satisfaction with wound management was 7 [5-8] versus 7 [5-8] (P = 0.81) in exposed compared with dressed study groups, respectively. In the wound-exposed patients, stated preference for wound exposure significantly increased from 35.5 to 57.5%, whereas in the wound-dressed patients, the stated preference for a dressed wound fell from 48.5 to 34.4% when assessed at recruitment (pre-randomisation) to day 28. There were no significant differences in inpatient additional dressing or gauze use for wound care, post-hospital discharge self-reported wound issues of infection, antibiotics, redness and inflammation, swollen, painful, and fluid leakage to day 28 across trial groups.

    CONCLUSION: The trial is underpowered as SSI rates were lower than expected. Nevertheless, leaving caesarean wounds exposed does not appear to have detrimental effects, provided patient counselling to manage expectations is undertaken.

    TWEETABLE ABSTRACT: An exposed compared with a dressed caesarean wound has a similar superficial surgical site infection rate, patient satisfaction and appearance.

  9. Samsuddin S, Arumugam PA, Md Amin MS, Yahya A, Musa N, Lim LL, et al.
    BJOG, 2020 03;127(4):490-499.
    PMID: 31778255 DOI: 10.1111/1471-0528.16031
    OBJECTIVE: To determine the association between maternal lipaemia and neonatal anthropometrics in Malaysian mother-offspring pairs.

    DESIGN: Prospective observational cohort study.

    SETTING: Single tertiary multidisciplinary antenatal clinic in Malaysia.

    POPULATION: A total of 507 mothers: 145 with gestational diabetes mellitus (GDM); 94 who were obese with normal glucose tolerance (NGT) (pre-gravid body mass index, BMI ≥ 27.5 kg/m2 ), and 268 who were not obese with NGT.

    METHODS: Maternal demographic, anthropometric, and clinical data were collected during an interview/examination using a structured questionnaire. Blood was drawn for insulin, C-peptide, triglyceride (Tg), and non-esterified fatty acid (NEFA) during the 75-g 2-hour oral glucose tolerance test (OGTT) screening, and again at 36 weeks of gestation. At birth, neonatal anthropometrics were assessed and data such as gestational weight gain (GWG) were extracted from the records.

    MAIN OUTCOME MEASURES: Macrosomia, large-for-gestational-age (LGA) status, cohort-specific birthweight (BW), neonatal fat mass (NFM), and sum of skinfold thickness (SSFT) > 90th centile.

    RESULTS: Fasting Tg > 95th centile (3.6 mmol/L) at screening for OGTT was independently associated with LGA (adjusted odds ratio, aOR 10.82, 95% CI 1.26-93.37) after adjustment for maternal glucose, pre-gravid BMI, and insulin sensitivity. Fasting glucose was independently associated with a birthweight ratio (BWR) of >90th centile (aOR 2.06, 95% CI 1.17-3.64), but not with LGA status, in this well-treated GDM cohort with pre-delivery HbA1c of 5.27%. In all, 45% of mothers had a pre-gravid BMI of <23 kg/m2 and 61% had a pre-gravid BMI of ≤ 25 kg/m2 , yet a GWG of >10 kg was associated with a 4.25-fold risk (95% CI 1.71-10.53) of BWR > 90th centile.

    CONCLUSION: Maternal lipaemia and GWG at a low threshold (>10 kg) adversely impact neonatal adiposity in Asian offspring, independent of glucose, insulin resistance and pre-gravid BMI. These may therefore be important modifiable metabolic targets in pregnancy.

    TWEETABLE ABSTRACT: Maternal lipids are associated with adiposity in Asian babies independently of pre-gravid BMI, GDM status, and insulin resistance.

  10. Ng, S. K., Tan, T. B., Tan, P. F., Chong, G. H., Tan, C. P.
    MyJurnal
    The effect of selected high pressure processing (HPP) parameters on the sensory attributes and
    shelf life of jackfruit bulb packed using vacuum skin (VS) and vacuum nylon (VN) packaging
    was studied. The samples were stored at chilled temperature (4°C) for shelf life study. HPP
    significantly (p < 0.05) increased the shelf life of VS- and VP-packed jackfruit bulbs to 60 d
    during chilled storage. In terms of colour stability during storage, both VS- and VP-packed
    HP-treated jackfruit bulbs exhibited no significant differences (p > 0.05) in L*, a*, and b*
    values. Also, the VS- and VP-packed HP-treated samples exhibited no significant differences
    (p > 0.05) in terms of texture. However, the sensory evaluation carried out among 48 panellists
    showed that there were significant differences (p < 0.05) between the untreated and HP-treated jackfruit bulbs. The aforementioned results had proven that HPP treatment of 500 MPa for
    5 min could successfully extend the shelf life and retain the physicochemical properties of
    jackfruit bulbs, regardless of the types of packaging used.
  11. Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Bergauer T, Brandstetter J, et al.
    Eur Phys J C Part Fields, 2020;80(3):237.
    PMID: 32215380 DOI: 10.1140/epjc/s10052-020-7773-5
    A search in an all-jet final state for new massive resonances decaying to W W , W Z , or Z Z boson pairs using a novel analysis method is presented. The analysis is performed on data corresponding to an integrated luminosity of 77.3 fb - 1 recorded with the CMS experiment at the LHC at a centre-of-mass energy of 13  Te . The search is focussed on potential narrow-width resonances with masses above 1.2  Te , where the decay products of each W or Z boson are expected to be collimated into a single, large-radius jet. The signal is extracted using a three-dimensional maximum likelihood fit of the two jet masses and the dijet invariant mass, yielding an improvement in sensitivity of up to 30% relative to previous search methods. No excess is observed above the estimated standard model background. In a heavy vector triplet model, spin-1 Z ' and W ' resonances with masses below 3.5 and 3.8   Te , respectively, are excluded at 95% confidence level. In a bulk graviton model, upper limits on cross sections are set between 27 and 0.2 fb for resonance masses between 1.2 and 5.2   Te , respectively. The limits presented in this paper are the best to date in the dijet final state.
  12. Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Asilar E, Bergauer T, et al.
    PMID: 31976986 DOI: 10.1140/epjc/s10052-019-7499-4
    New sets of CMS underlying-event parameters ("tunes") are presented for the pythia8 event generator. These tunes use the NNPDF3.1 parton distribution functions (PDFs) at leading (LO), next-to-leading (NLO), or next-to-next-to-leading (NNLO) orders in perturbative quantum chromodynamics, and the strong coupling evolution at LO or NLO. Measurements of charged-particle multiplicity and transverse momentum densities at various hadron collision energies are fit simultaneously to determine the parameters of the tunes. Comparisons of the predictions of the new tunes are provided for observables sensitive to the event shapes at LEP, global underlying event, soft multiparton interactions, and double-parton scattering contributions. In addition, comparisons are made for observables measured in various specific processes, such as multijet, Drell-Yan, and top quark-antiquark pair production including jet substructure observables. The simulation of the underlying event provided by the new tunes is interfaced to a higher-order matrix-element calculation. For the first time, predictions from pythia8 obtained with tunes based on NLO or NNLO PDFs are shown to reliably describe minimum-bias and underlying-event data with a similar level of agreement to predictions from tunes using LO PDF sets.
  13. Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Asilar E, Bergauer T, et al.
    Eur Phys J C Part Fields, 2020;80(12):1164.
    PMID: 33362286 DOI: 10.1140/epjc/s10052-020-08562-y
    Measurements are presented of the single-diffractive dijet cross section and the diffractive cross section as a function of the proton fractional momentum loss ξ and the four-momentum transfer squared t. Both processes p pp X and p p → X p , i.e. with the proton scattering to either side of the interaction point, are measured, where X includes at least two jets; the results of the two processes are averaged. The analyses are based on data collected simultaneously with the CMS and TOTEM detectors at the LHC in proton-proton collisions at s = 8 Te during a dedicated run with β ∗ = 90 m at low instantaneous luminosity and correspond to an integrated luminosity of 37.5 nb - 1 . The single-diffractive dijet cross section σ jj p X , in the kinematic region ξ < 0.1 , 0.03 < | t | < 1 Ge 2 , with at least two jets with transverse momentum p T > 40 Ge , and pseudorapidity | η | < 4.4 , is 21.7 ± 0.9 (stat) - 3.3 + 3.0 (syst) ± 0.9 (lumi) nb . The ratio of the single-diffractive to inclusive dijet yields, normalised per unit of ξ , is presented as a function of x, the longitudinal momentum fraction of the proton carried by the struck parton. The ratio in the kinematic region defined above, for x values in the range - 2.9 ≤ log 10 x ≤ - 1.6 , is R = ( σ jj p X / Δ ξ ) / σ jj = 0.025 ± 0.001 (stat) ± 0.003 (syst) , where σ jj p X and σ jj are the single-diffractive and inclusive dijet cross sections, respectively. The results are compared with predictions from models of diffractive and nondiffractive interactions. Monte Carlo predictions based on the HERA diffractive parton distribution functions agree well with the data when corrected for the effect of soft rescattering between the spectator partons.
  14. 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.
  15. Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Bergauer T, Brandstetter J, et al.
    Eur Phys J C Part Fields, 2020;80(8):718.
    PMID: 32834020 DOI: 10.1140/epjc/s10052-020-8166-5
    Central exclusive and semiexclusive production of pairs is measured with the CMS detector in proton-proton collisions at the LHC at center-of-mass energies of 5.02 and 13TeV. The theoretical description of these nonperturbative processes, which have not yet been measured in detail at the LHC, poses a significant challenge to models. The two pions are measured and identified in the CMS silicon tracker based on specific energy loss, whereas the absence of other particles is ensured by calorimeter information. The total and differential cross sections of exclusive and semiexclusive central production are measured as functions of invariant mass, transverse momentum, and rapidity of the system in the fiducial region defined as transverse momentum and pseudorapidity . The production cross sections for the four resonant channels , , , and are extracted using a simple model. These results represent the first measurement of this process at the LHC collision energies of 5.02 and 13TeV.
  16. Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Bergauer T, Brandstetter J, et al.
    Eur Phys J C Part Fields, 2020;80(5):370.
    PMID: 32633732 DOI: 10.1140/epjc/s10052-020-7858-1
    A measurement is presented of differential cross sections for t-channel single top quark and antiquark production in proton-proton collisions at a centre-of-mass energy of 13 Te by the CMS experiment at the LHC. From a data set corresponding to an integrated luminosity of 35.9 fb - 1 , events containing one muon or electron and two or three jets are analysed. The cross section is measured as a function of the top quark transverse momentum ( p T ), rapidity, and polarisation angle, the charged lepton p T and rapidity, and the p T of the W  boson from the top quark decay. In addition, the charge ratio is measured differentially as a function of the top quark, charged lepton, and W  boson kinematic observables. The results are found to be in agreement with standard model predictions using various next-to-leading-order event generators and sets of parton distribution functions. Additionally, the spin asymmetry, sensitive to the top quark polarisation, is determined from the differential distribution of the polarisation angle at parton level to be 0.440 ± 0.070 , in agreement with the standard model prediction.
  17. 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 ℓ ν jj final state (with ℓ 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 / Λ 2 < 2.5 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 < 2.0 Te - 2 .
  18. Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Bergauer T, Brandstetter J, et al.
    Phys Rev Lett, 2019 Dec 13;123(24):241801.
    PMID: 31922872 DOI: 10.1103/PhysRevLett.123.241801
    Results are reported from a search for new particles that decay into a photon and two gluons, in events with jets. Novel jet substructure techniques are developed that allow photons to be identified in an environment densely populated with hadrons. The analyzed proton-proton collision data were collected by the CMS experiment at the LHC, in 2016 at sqrt[s]=13  TeV, and correspond to an integrated luminosity of 35.9  fb^{-1}. The spectra of total transverse hadronic energy of candidate events are examined for deviations from the standard model predictions. No statistically significant excess is observed over the expected background. The first cross section limits on new physics processes resulting in such events are set. The results are interpreted as upper limits on the rate of gluino pair production, utilizing a simplified stealth supersymmetry model. The excluded gluino masses extend up to 1.7 TeV, for a neutralino mass of 200 GeV and exceed previous mass constraints set by analyses targeting events with isolated photons.
  19. Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Bergauer T, Brandstetter J, et al.
    Phys Rev Lett, 2019 Dec 06;123(23):231803.
    PMID: 31868480 DOI: 10.1103/PhysRevLett.123.231803
    A search for narrow low-mass resonances decaying to quark-antiquark pairs is presented. The search is based on proton-proton collision events collected at 13 TeV by the CMS detector at the CERN LHC. The data sample corresponds to an integrated luminosity of 35.9  fb^{-1}, recorded in 2016. The search considers the case where the resonance has high transverse momentum due to initial-state radiation of a hard photon. To study this process, the decay products of the resonance are reconstructed as a single large-radius jet with two-pronged substructure. The signal would be identified as a localized excess in the jet invariant mass spectrum. No evidence for such a resonance is observed in the mass range 10 to 125 GeV. Upper limits at the 95% confidence level are set on the coupling strength of resonances decaying to quark pairs. The results obtained with this photon trigger strategy provide the first direct constraints on quark-antiquark resonance masses below 50 GeV obtained at a hadron collider.
  20. Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Bergauer T, Brandstetter J, et al.
    Phys Rev Lett, 2019 Sep 27;123(13):131802.
    PMID: 31697516 DOI: 10.1103/PhysRevLett.123.131802
    A search for a light charged Higgs boson (H^{+}) decaying to a W boson and a CP-odd Higgs boson (A) in final states with eμμ or μμμ is performed using data from pp collisions at sqrt[s]=13  TeV, recorded by the CMS detector at the LHC and corresponding to an integrated luminosity of 35.9  fb^{-1}. In this search, it is assumed that the H^{+} boson is produced in decays of top quarks, and the A boson decays to two oppositely charged muons. The presence of signals for H^{+} boson masses between 100 and 160 GeV and A boson masses between 15 and 75 GeV is investigated. No evidence for the production of the H^{+} boson is found. Upper limits at 95% confidence level are obtained on the combined branching fraction for the decay chain, t→bH^{+}→bW^{+}A→bW^{+}μ^{+}μ^{-}, of 1.9×10^{-6} to 8.6×10^{-6}, depending on the masses of the H^{+} and A bosons. These are the first limits for these decay modes of the H^{+} and A bosons.
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