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  1. Fulltext 2013 dengue outbreaks in Singapore and Malaysia caused by different viral strains
    Ng LC, Chem YK, Koo C, Mudin RNB, Amin FM, Lee KS, et al.
    Am J Trop Med Hyg, 2015 Jun;92(6):1150-1155.
    PMID: 25846296 DOI: 10.4269/ajtmh.14-0588
    Characterization of 14,079 circulating dengue viruses in a cross-border surveillance program, UNITEDengue, revealed that the 2013 outbreaks in Singapore and Malaysia were associated with replacement of predominant serotype. While the predominant virus in Singapore switched from DENV2 to DENV1, DENV2 became predominant in neighboring Malaysia. Dominance of DENV2 was most evident on the southern states where higher fatality rates were observed.
  2. A Cross-Sectional Study on the Use of, Preference for, and Perceived Reliability of Mass Media for Drug-Related Information Among the General Public in Sarawak
    Ting CY, Abd Wahab MS, Lee KS, Tan RT, Ming LC
    Ther Innov Regul Sci, 2017 Mar;51(2):212-220.
    PMID: 30231729 DOI: 10.1177/2168479016674041
    BACKGROUND: Because of the large size of Sarawak and the high proportion of people residing in rural areas in this Malaysian state, disseminating drug-related information there can be challenging. It is, therefore, important to recognize the type of mass media for drug-related information that are salient to the people of Sarawak. This study was aimed at identifying the use of and the preferences for mass media to obtain drug-related information among the public in Sarawak. We also aimed to recognize the media perceived as the most reliable for drug-related information.

    METHODS: This was a cross-sectional study using a self-administered questionnaire carried out from September to October 2013. Survey respondents were recruited from 4 divisions in Sarawak: Kuching, Sibu, Miri, and Bintulu.

    RESULTS: A total of 433 completed questionnaires were obtained at the end of the study period. All respondents had access to common mass media such as television (89.8%, 389/433), radio (68.6%, 297/433), and the Internet (66.1%, 286/433). Among all respondents, television (71.4%, 309/433) was noted as the most preferred media for drug-related information. Compared with rural respondents, urban respondents were significantly more likely to have access to and prefer the Internet to obtain drug-related information. On the other hand, rural respondents were more likely to have access to and prefer radio for such information compared to their urban counterparts.

    CONCLUSIONS: Television can be an important and attractive choice of mass media in a quality use of medicines (QUM) campaign. The Internet can be used to disseminate drug-related information in urban areas, whereas radio can be used in a QUM campaign targeting the rural public.

  3. Fulltext A Deep Neural Network for Simultaneous Estimation of b Jet Energy and Resolution
    Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Bergauer T, Dragicevic M, et al.
    Comput Softw Big Sci, 2020;4(1):10.
    PMID: 33196702 DOI: 10.1007/s41781-020-00041-z
    We describe a method to obtain point and dispersion estimates for the energies of jets arising from b quarks produced in proton-proton collisions at an energy of s = 13 TeV at the CERN LHC. The algorithm is trained on a large sample of simulated b jets and validated on data recorded by the CMS detector in 2017 corresponding to an integrated luminosity of 41 fb - 1 . A multivariate regression algorithm based on a deep feed-forward neural network employs jet composition and shape information, and the properties of reconstructed secondary vertices associated with the jet. The results of the algorithm are used to improve the sensitivity of analyses that make use of b jets in the final state, such as the observation of Higgs boson decay to b b ¯ .
  4. Fulltext A multi-dimensional search for new heavy resonances decaying to boosted W W , W Z , or Z Z boson pairs in the dijet final state at 13  Te
    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.
  5. A search for decays of the Higgs boson to invisible particles in events with a top-antitop quark pair or a vector boson in proton-proton collisions at s=13TeV
    Tumasyan A, Adam W, Andrejkovic JW, Bergauer T, Chatterjee S, Damanakis K, et al.
    Eur Phys J C Part Fields, 2023;83(10):933.
    PMID: 37855556 DOI: 10.1140/epjc/s10052-023-11952-7
    A search for decays to invisible particles of Higgs bosons produced in association with a top-antitop quark pair or a vector boson, which both decay to a fully hadronic final state, has been performed using proton-proton collision data collected at s=13TeV by the CMS experiment at the LHC, corresponding to an integrated luminosity of 138fb-1. The 95% confidence level upper limit set on the branching fraction of the 125GeV Higgs boson to invisible particles, B(H→inv), is 0.54 (0.39 expected), assuming standard model production cross sections. The results of this analysis are combined with previous B(H→inv) searches carried out at s=7, 8, and 13TeV in complementary production modes. The combined upper limit at 95% confidence level on B(H→inv) is 0.15 (0.08 expected).
  6. Fulltext A search for new phenomena in pp collisions at [Formula: see text] in final states with missing transverse momentum and at least one jet using the [Formula: see text] variable
    Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Asilar E, Bergauer T, et al.
    Eur Phys J C Part Fields, 2017;77(5):294.
    PMID: 28579921 DOI: 10.1140/epjc/s10052-017-4787-8
    A search for new phenomena is performed in final states containing one or more jets and an imbalance in transverse momentum in pp collisions at a centre-of-mass energy of 13[Formula: see text]. The analysed data sample, recorded with the CMS detector at the CERN LHC, corresponds to an integrated luminosity of 2.3[Formula: see text]. Several kinematic variables are employed to suppress the dominant background, multijet production, as well as to discriminate between other standard model and new physics processes. The search provides sensitivity to a broad range of new-physics models that yield a stable weakly interacting massive particle. The number of observed candidate events is found to agree with the expected contributions from standard model processes, and the result is interpreted in the mass parameter space of fourteen simplified supersymmetric models that assume the pair production of gluinos or squarks and a range of decay modes. For models that assume gluino pair production, masses up to 1575 and 975[Formula: see text] are excluded for gluinos and neutralinos, respectively. For models involving the pair production of top squarks and compressed mass spectra, top squark masses up to 400[Formula: see text] are excluded.
  7. Azimuthal Correlations within Exclusive Dijets with Large Momentum Transfer in Photon-Lead Collisions
    Tumasyan A, Adam W, Bergauer T, Dragicevic M, Del Valle AE, Frühwirth R, et al.
    Phys Rev Lett, 2023 Aug 04;131(5):051901.
    PMID: 37595238 DOI: 10.1103/PhysRevLett.131.051901
    The structure of nucleons is multidimensional and depends on the transverse momenta, spatial geometry, and polarization of the constituent partons. Such a structure can be studied using high-energy photons produced in ultraperipheral heavy-ion collisions. The first measurement of the azimuthal angular correlations of exclusively produced events with two jets in photon-lead interactions at large momentum transfer is presented, a process that is considered to be sensitive to the underlying nuclear gluon polarization. This study uses a data sample of ultraperipheral lead-lead collisions at sqrt[s_{NN}]=5.02  TeV, corresponding to an integrated luminosity of 0.38  nb^{-1}, collected with the CMS experiment at the LHC. The measured second harmonic of the correlation between the sum and difference of the two jet transverse momentum vectors is found to be positive, and rising, as the dijet transverse momentum increases. A well-tuned model that has been successful at describing a wide range of proton scattering data from the HERA experiments fails to describe the observed correlations, suggesting the presence of gluon polarization effects.
  8. Azimuthal correlations in Z +jets events in proton-proton collisions at s=13TeV
    Tumasyan A, Adam W, Andrejkovic JW, Bergauer T, Chatterjee S, Damanakis K, et al.
    Eur Phys J C Part Fields, 2023;83(8):722.
    PMID: 37578844 DOI: 10.1140/epjc/s10052-023-11833-z
    The production of Z bosons associated with jets is measured in pp collisions at s=13TeV with data recorded with the CMS experiment at the LHC corresponding to an integrated luminosity of 36.3fb-1. The multiplicity of jets with transverse momentum pT>30GeV is measured for different regions of the Z boson's pT(Z), from lower than 10GeV to higher than 100GeV. The azimuthal correlation Δϕ between the Z boson and the leading jet, as well as the correlations between the two leading jets are measured in three regions of pT(Z). The measurements are compared with several predictions at leading and next-to-leading orders, interfaced with parton showers. Predictions based on transverse-momentum dependent parton distributions and corresponding parton showers give a good description of the measurement in the regions where multiple parton interactions and higher jet multiplicities are not important. The effects of multiple parton interactions are shown to be important to correctly describe the measured spectra in the low pT(Z) regions.
  9. Fulltext Azimuthal separation in nearly back-to-back jet topologies in inclusive 2- and 3-jet events in pp collisions at s = 13 Te
    Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Asilar E, Bergauer T, et al.
    Eur Phys J C Part Fields, 2019;79(9):773.
    PMID: 31713548 DOI: 10.1140/epjc/s10052-019-7276-4
    A measurement for inclusive 2- and 3-jet events of the azimuthal correlation between the two jets with the largest transverse momenta, Δ ϕ 12 , is presented. The measurement considers events where the two leading jets are nearly collinear ("back-to-back") in the transverse plane and is performed for several ranges of the leading jet transverse momentum. Proton-proton collision data collected with the CMS experiment at a center-of-mass energy of 13 Te and corresponding to an integrated luminosity of 35.9 fb - 1 are used. Predictions based on calculations using matrix elements at leading-order and next-to-leading-order accuracy in perturbative quantum chromodynamics supplemented with leading-log parton showers and hadronization are generally in agreement with the measurements. Discrepancies between the measurement and theoretical predictions are as large as 15%, mainly in the region 177 ∘ < Δ ϕ 12 < 180 ∘ . The 2- and 3-jet measurements are not simultaneously described by any of models.
  10. Fulltext CMS pythia  8 colour reconnection tunes based on underlying-event data
    Tumasyan A, Adam W, Andrejkovic JW, Bergauer T, Chatterjee S, Damanakis K, et al.
    Eur Phys J C Part Fields, 2023;83(7):587.
    PMID: 37440247 DOI: 10.1140/epjc/s10052-023-11630-8
    New sets of parameter tunes for two of the colour reconnection models, quantum chromodynamics-inspired and gluon-move, implemented in the pythia  8 event generator, are obtained based on the default CMS pythia  8 underlying-event tune, CP5. Measurements sensitive to the underlying event performed by the CMS experiment at centre-of-mass energies s=7 and 13TeV, and by the CDF experiment at 1.96TeV are used to constrain the parameters of colour reconnection models and multiple-parton interactions simultaneously. The new colour reconnection tunes are compared with various measurements at 1.96, 7, 8, and 13TeV including measurements of the underlying-event, strange-particle multiplicities, jet substructure observables, jet shapes, and colour flow in top quark pair (tt¯) events. The new tunes are also used to estimate the uncertainty related to colour reconnection modelling in the top quark mass measurement using the decay products of tt¯ events in the semileptonic channel at 13TeV.
  11. Fulltext Cancer protective effects of plums: A systematic review
    Bahrin AA, Moshawih S, Dhaliwal JS, Kanakal MM, Khan A, Lee KS, et al.
    Biomed Pharmacother, 2022 Feb;146:112568.
    PMID: 34963086 DOI: 10.1016/j.biopha.2021.112568
    Plums is one of the most cultivated stone fruits due to its fast growing popularity. It has various traditionally recognized health benefits. There are two main commercial types of plums: the European plum (Prunus domestica) and the Japanese plum (Prunus salicina), each having many varieties. Researchers are gathering further evidence of pharmacological effects for plums by scientifically studying its anti-inflammatory, antioxidant properties. A systematic review analysing the literature related to the effects of plums on prevention and treatment of cancer is warranted. This is the first review examining the cancer-related effects of plums. Antioxidation properties of the active constituents of plum were also compared. Scopus, Google Scholar, PubMed, Medxriv and Cochrane Library databases, from their date of inception until July 2021 were utilized. The risk of bias was assessed using CONSORT checklist. A total of 6639 studies were screened and eventually only 54 studies were included. Full-text review of included studies revealed that plum extracts were rich in antioxidants. Overall, most of the studies that fulfilled the eligibility criteria were in vitro and a few clinical studies involving in vivo work. Therefore, it would be beneficial to perform more studies on animals or humans, to confirm that the result obtained from these in vitro studies are able to be extrapolated in a wider range of applications. Further clinical and in vivo studies are warranted to validate plums as a functional food for treatment and prevention of cancer.
  12. Fulltext Circulating vaccine-derived poliovirus: a menace to the end game of polio eradication
    Ming LC, Hussain Z, Yeoh SF, Koh D, Lee KS
    Global Health, 2020 07 16;16(1):63.
    PMID: 32677974 DOI: 10.1186/s12992-020-00594-z
    The World Health Organisation Western Pacific Region countries were declared free of polio in 2000 until a polio outbreak involving 305 cases occurred in Indonesia in 2006. It was not until 2014 that the World Health Organisation South East Asia region was officially declared polio-free again. However, in February 2019, the Global Polio Eradication Initiative announced a new circulating vaccine-derived poliovirus outbreak in the Papua province of Indonesia. To make matter worse, the outbreak responses were tardy and led to transmission among migrating communities to other cities. The pressing regional issues of polio outbreak caused by circulating vaccine-derived poliovirus and use of oral polio vaccine have not been well presented. Our letter highlighted the suboptimal outbreak responses as well as the necessity of cross-border vaccination to curb continued poliovirus transmission.
  13. Fulltext Cold chain time- and temperature-controlled transport of vaccines: a simulated experimental study
    Ng CZ, Lean YL, Yeoh SF, Lean QY, Lee KS, Suleiman AK, et al.
    Clin Exp Vaccine Res, 2020 Jan;9(1):8-14.
    PMID: 32095436 DOI: 10.7774/cevr.2020.9.1.8
    Purpose: The objective of this research was to examine the cold chain temperature maintenance for the supply of vaccines and other biological products by pharmaceutical wholesaler.

    Materials and Methods: In this study, six configurations using cold vaccine boxes or bags made with different materials, with and without insulation, of different sizes, and number of coolant-packs were used to simulate the configuration used by the pharmaceutical wholesalers for transportation of vaccine. Model vaccines (vial, n=10) were packed using these six configurations which then stored in an incubator at 38℃ and monitored for 24 hours. Each configuration was tested repeatedly for 5 times.

    Results: In term of compliance to 2℃-8℃, four out of six tested configurations are effective in cold chain transportation. The effectiveness is highly dependent on the type of passive containers used, size of cold boxes, insulation, and number of coolant-packs. The configuration with a larger polystyrene foam box with five coolant-packs maintained the required temperature up to 23 hours. In contrast, configurations using a polystyrene foam box with four coolant-packs and a large vaccine cold box with two coolant-packs failed to reach below 8℃ throughout the 24 hours.

    Conclusion: Packaging method, the material and size of the container could have a direct impact on the effectiveness of cold chain temperature maintenance. Polystyrene foam box, cold box with polyethylene interior lining and polypropylene insulation, a cooler bag with proper number of ice packs could be effectively used for transportation of vaccines within their respective transportation duration allowance.

  14. Fulltext Combating Sale of Counterfeit and Falsified Medicines Online: A Losing Battle
    Lee KS, Yee SM, Zaidi STR, Patel RP, Yang Q, Al-Worafi YM, et al.
    Front Pharmacol, 2017;8:268.
    PMID: 28559845 DOI: 10.3389/fphar.2017.00268
  15. Combination of Searches for Higgs Boson Pair Production in Proton-Proton Collisions at sqrt[s]=13  TeV
    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.
  16. Fulltext Combined measurements of Higgs boson couplings in proton-proton collisions at s = 13 Te
    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.
  17. Fulltext Combined searches for the production of supersymmetric top quark partners in proton-proton collisions at s = 13 Te
    Tumasyan A, Adam W, Andrejkovic JW, Bergauer T, Chatterjee S, Dragicevic M, et al.
    Eur Phys J C Part Fields, 2021;81(11):970.
    PMID: 34793584 DOI: 10.1140/epjc/s10052-021-09721-5
    A combination of searches for top squark pair production using proton-proton collision data at a center-of-mass energy of 13 Te at the CERN LHC, corresponding to an integrated luminosity of 137 fb - 1 collected by the CMS experiment, is presented. Signatures with at least 2 jets and large missing transverse momentum are categorized into events with 0, 1, or 2 leptons. New results for regions of parameter space where the kinematical properties of top squark pair production and top quark pair production are very similar are presented. Depending on the model, the combined result excludes a top squark mass up to 1325 Ge for a massless neutralino, and a neutralino mass up to 700 Ge for a top squark mass of 1150 Ge . Top squarks with masses from 145 to 295 Ge , for neutralino masses from 0 to 100 Ge , with a mass difference between the top squark and the neutralino in a window of 30 Ge around the mass of the top quark, are excluded for the first time with CMS data. The results of theses searches are also interpreted in an alternative signal model of dark matter production via a spin-0 mediator in association with a top quark pair. Upper limits are set on the cross section for mediator particle masses of up to 420 Ge .
  18. Constraining Gluon Distributions in Nuclei Using Dijets in Proton-Proton and Proton-Lead Collisions at sqrt[s_{NN}]=5.02  TeV
    Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Asilar E, Bergauer T, et al.
    Phys Rev Lett, 2018 Aug 10;121(6):062002.
    PMID: 30141647 DOI: 10.1103/PhysRevLett.121.062002
    The pseudorapidity distributions of dijets as functions of their average transverse momentum (p_{T}^{ave}) are measured in proton-lead (pPb) and proton-proton (pp) collisions. The data samples were collected by the CMS experiment at the CERN LHC, at a nucleon-nucleon center-of-mass energy of 5.02 TeV. A significant modification of the pPb spectra with respect to the pp spectra is observed in all p_{T}^{ave} intervals investigated. The ratios of the pPb and pp distributions are compared to next-to-leading order perturbative quantum chromodynamics calculations with unbound nucleon and nuclear parton distribution functions (PDFs). These results give the first evidence that the gluon PDF at large Bjorken x in lead ions is strongly suppressed with respect to the PDF in unbound nucleons.
  19. Constraints on parton distribution functions and extraction of the strong coupling constant from the inclusive jet cross section in pp collisions at [Formula: see text][Formula: see text]
    Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Bergauer T, Dragicevic M, et al.
    Eur Phys J C Part Fields, 2015 06 26;75(6):288.
    PMID: 26146483
    The inclusive jet cross section for proton-proton collisions at a centre-of-mass energy of 7[Formula: see text] was measured by the CMS Collaboration at the LHC with data corresponding to an integrated luminosity of 5.0[Formula: see text]. The measurement covers a phase space up to 2[Formula: see text] in jet transverse momentum and 2.5 in absolute jet rapidity. The statistical precision of these data leads to stringent constraints on the parton distribution functions of the proton. The data provide important input for the gluon density at high fractions of the proton momentum and for the strong coupling constant at large energy scales. Using predictions from perturbative quantum chromodynamics at next-to-leading order, complemented with electroweak corrections, the constraining power of these data is investigated and the strong coupling constant at the Z boson mass [Formula: see text] is determined to be [Formula: see text], which is in agreement with the world average.
  20. Constraints on the Initial State of Pb-Pb Collisions via Measurements of Z-Boson Yields and Azimuthal Anisotropy at sqrt[s_{NN}]=5.02  TeV
    Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Bergauer T, Dragicevic M, et al.
    Phys Rev Lett, 2021 Sep 03;127(10):102002.
    PMID: 34533355 DOI: 10.1103/PhysRevLett.127.102002
    The CMS experiment at the LHC has measured the differential cross sections of Z bosons decaying to pairs of leptons, as functions of transverse momentum and rapidity, in lead-lead collisions at a nucleon-nucleon center-of-mass energy of 5.02  TeV. The measured Z boson elliptic azimuthal anisotropy coefficient is compatible with zero, showing that Z bosons do not experience significant final-state interactions in the medium produced in the collision. Yields of Z bosons are compared to Glauber model predictions and are found to deviate from these expectations in peripheral collisions, indicating the presence of initial collision geometry and centrality selection effects. The precision of the measurement allows, for the first time, for a data-driven determination of the nucleon-nucleon integrated luminosity as a function of lead-lead centrality, thereby eliminating the need for its estimation based on a Glauber model.
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