Displaying publications 1 - 20 of 107 in total

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  1. Health impacts of Facebook usage and mobile texting among undergraduate dental students: it's time to understand the difference between usage and an excessive use
    Lee YL, Verma RK, Yadav H, Barua A
    Eur J Dent Educ, 2016 Nov;20(4):218-228.
    PMID: 26277860 DOI: 10.1111/eje.12164
    BACKGROUND: Facebook and mobile texting are prevalent in the lives of almost every student. However, little is known about the relationship between Facebook usage or mobile texting and their impacts on health amongst undergraduate dental students. In this study, excessive Facebook use and excessive mobile texting were studied as they relate to impacts on health.

    MATERIALS AND METHODS: A cross-sectional study was conducted at a private university in Malaysia. A total of 188 undergraduate dental students were interviewed using a pre-tested and self-rated questionnaire. Data collected from participants were analysed using SPSS version 18.0. Chi-square test, Fisher's exact test and multiple logistic regression analyses were applied to study the relationship between explanatory variables and excessive Facebook use and excessive mobile texting.

    RESULTS: The prevalence of excessive Facebook use and excessive mobile texting amongst undergraduate dental students was found to be 33.2% and 33.0%, respectively. According to a multivariate analysis, texting habits, such as the presence of daytime sleepiness after texting late at night (aOR = 2.682, 95% CI = 1.142-6.301) and the presence of anxious feelings if students failed to receive a timely response (aOR = 3.819, 95% CI = 1.580-9.230), were determined to be significant predictors of excessive mobile texting. Excessive Facebook use was found to be significantly related to three variables as follows: fewer numbers of close friends (aOR = 2.275, 95% CI = 1.057-4.898), the checking of updates on the Facebook walls of their friends (aOR = 2.582, 95% CI = 1.189-5.605) and the absence of active and vigorous feelings during Facebook use (aOR = 3.401, 95% CI = 1.233-9.434).

    CONCLUSIONS: Approximately one-third of undergraduate dental students in this study experienced excessive Facebook use and/or excessive mobile texting. Health education and promotion should be instituted to create awareness, whilst students should be advised to practise self-control with respect to both mobile texting and Facebook usage.

  2. In silico studies, synthesis and anticancer activity of novel diphenyl ether-based pyridine derivatives
    Verma R, Bairy I, Tiwari M, Bhat GV, Shenoy GG
    Mol Divers, 2019 Aug;23(3):541-554.
    PMID: 30430400 DOI: 10.1007/s11030-018-9889-1
    A series of novel 2-amino-4-(3-hydroxy-4-phenoxyphenyl)-6-(4-substituted phenyl) nicotinonitriles were synthesized and evaluated against HepG2, A-549 and Vero cell lines. Compounds 3b (IC50 16.74 ± 0.45 µM) and 3p (IC50 10.57 ± 0.54 µM) were found to be the most active compounds against A-549 cell line among the evaluated compounds. Further 3b- and 3p-induced apoptosis was characterized by AO/EB (acridine orange/ethidium bromide) nuclear staining method and also by DNA fragmentation study. A decrease in cell viability and initiation of apoptosis was clearly evident through the morphological changes in the A-549 cells treated with 3b and 3p when stained with this method. Fragmentation of DNA into nucleosomes was observed which further confirmed the cell apoptosis in cells treated with compound 3b. Flow cytometry studies confirmed the cell cycle arrest at G2/M phase in A549 cells treated with compound 3b. Further in silico studies performed supported the in vitro anticancer activity of these compounds as depicted by dock score and binding energy values.
  3. Fulltext Anticonvulsant activity of Morus alba and its effect on brain gamma-aminobutyric acid level in rats
    Gupta G, Afzal M, David SR, Verma R, Candaswamy M, Anwar F
    Pharmacognosy Res, 2014 Apr;6(2):188-9.
    PMID: 24761125 DOI: 10.4103/0974-8490.129046
  4. Synthesis, evaluation, molecular docking, and molecular dynamics studies of novel N-(4-[pyridin-2-yloxy]benzyl)arylamine derivatives as potential antitubercular agents
    Verma R, Boshoff HIM, Arora K, Bairy I, Tiwari M, Varadaraj BG, et al.
    Drug Dev Res, 2020 05;81(3):315-328.
    PMID: 31782209 DOI: 10.1002/ddr.21623
    A new series of novel triclosan (2,4,4'-trichloro-2'-hydroxydiphenylether) analogues were designed, synthesized, and screened for their in vitro antimycobacterial and antibacterial activities. Most of the compounds showed significant activity against Mycobacterium tuberculosis H37Rv strain with minimum inhibitory concentration (MIC) values in 20-40 μM range in GAST/Fe medium when compared with triclosan (43 μM) in the first week of assay, and after additional incubation, seven compounds, that is, 2a, 2c, 2g, 2h, 2i, 2j, and 2m, exhibited MIC values at the concentration of 20-40 μM. The compounds also showed more significant activity against Bacillus subtilis and Staphylococcus aureus. The synthesized compounds showed druggable properties, and the predicted ADME (absorption, distribution, metabolism, and excretion) properties were within the acceptable limits. The in silico studies predicted better interactions of compounds with target protein residues and a higher dock score in comparison with triclosan. Molecular dynamics simulation study of the most active compound 2i was performed in order to further explore the stability of the protein-ligand complex and the protein-ligand interaction in detail.
  5. On the discrimination between facial creams of different brands using Raman Spectroscopy and partial least squares discriminant analysis for forensic application
    Asri MNM, Verma R, Ibrahim MH, Nor NAM, Sharma V, Ismail D
    Sci Justice, 2021 Nov;61(6):687-696.
    PMID: 34802642 DOI: 10.1016/j.scijus.2021.08.006
    Determining the origin of cosmetic traces is an important aspect of forensic investigations, that helps linking a suspect to a crime. Such type of evidence can help further narrow down the undergoing investigations. This paper reports the first use of Raman Spectroscopy (RS) coupled with the exploratory principal component analysis (PCA) and supervised partial least squares-discriminant analysis (PLS-DA) in facial creams. 40 facial cream samples of 8 different brands were studied in this work. Preliminary assessments through visual inspection of their Raman spectra revealed the presence of oxides, titanium dioxide, castor seed oil, and beeswax. Also, the peaks of alkyne groups were indicative of the presence of talc or mica compounds. The exploratory PCA correctly segregated the samples into 8 clusters and the supervised PLS-DA model correctly classified them into 8 classes. Further evaluation of the performance of the trained PLS-DA model resulted in perfect classification shown by the receiver operating characteristic (ROC) curves. The PLS-DA model also resulted in 100% accuracy of correctly assigning the brand on the face wipes on each of the five substrates viz. cotton, dry and wet tissue paper, nylon substrate, and polyester. This validation was done treating these samples as unknowns. The study has a potential for use under actual forensic casework conditions.
  6. Rapid and nondestructive analysis of lipstick on different substrates using ATR-FTIR spectroscopy and chemometrics
    Ka Khei L, Verma R, Tan ELY, Low KH, Ismail D, Mohamad Asri MN
    J Forensic Sci, 2023 Feb 15.
    PMID: 36789805 DOI: 10.1111/1556-4029.15223
    Lipstick can be an important piece of evidence in crimes like murders, rapes, and suicides. Due to its prevalence, it can be an important corroborative evidence in crime reconstruction. The analysis of such evidence can provide an evidentiary link between the suspect, the victim, object, or the crime scene. We report the use of nondestructive ATR-FTIR spectroscopy combined with chemometrics for the classification of 10 brands of lipsticks with nine samples each. Chemometric method of partial least square-discriminant analysis (PLS-DA) has been employed to interpret the data and classify the samples into their respective classes. The PLS-DA model provides an AUC figure above 0.99 in all brands except one; for which it is slightly less at 0.94. We have also tested the traces of these lipstick samples on different substrates treating them as unknowns in the already trained PLS-DA model. 100% of the samples on nine substrates viz. a cotton, nylon, plastic, dry tissue, denim (blue jeans), wet tissue, nitrile gloves, white paper, and polyester were correctly attributed to their source brand. In conclusion, the results suggest that ATR-FTIR combined with the chemometrics is a rapid, nondestructive, and accurate method for the discrimination and source attribution of lipstick. This study has potential for use in actual forensic casework conditions.
  7. Fulltext Phytoantioxidant Functionalized Nanoparticles: A Green Approach to Combat Nanoparticle-Induced Oxidative Stress
    Balkrishna A, Kumar A, Arya V, Rohela A, Verma R, Nepovimova E, et al.
    Oxid Med Cell Longev, 2021;2021:3155962.
    PMID: 34737844 DOI: 10.1155/2021/3155962
    Nanotechnology is gaining significant attention, with numerous biomedical applications. Silver in wound dressings, copper oxide and silver in antibacterial preparations, and zinc oxide nanoparticles as a food and cosmetic ingredient are common examples. However, adverse effects of nanoparticles in humans and the environment from extended exposure at varied concentrations have yet to be established. One of the drawbacks of employing nanoparticles is their tendency to cause oxidative stress, a significant public health concern with life-threatening consequences. Cardiovascular, renal, and respiratory problems and diabetes are among the oxidative stress-related disorders. In this context, phytoantioxidant functionalized nanoparticles could be a novel and effective alternative. In addition to performing their intended function, they can protect against oxidative damage. This review was designed by searching through various websites, books, and articles found in PubMed, Science Direct, and Google Scholar. To begin with, oxidative stress, its related diseases, and the mechanistic basis of oxidative damage caused by nanoparticles are discussed. One of the main mechanisms of action of nanoparticles was unearthed to be oxidative stress, which limits their use in humans. Secondly, the role of phytoantioxidant functionalized nanoparticles in oxidative damage prevention is critically discussed. The parameters for the characterization of nanoparticles were also discussed. The majority of silver, gold, iron, zinc oxide, and copper nanoparticles produced utilizing various plant extracts were active free radical scavengers. This potential is linked to several surface fabricated phytoconstituents, such as flavonoids and phenols. These phytoantioxidant functionalized nanoparticles could be a better alternative to nanoparticles prepared by other existing approaches.
  8. Observation of the B_{s}^{0}→X(3872)ϕ Decay
    Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Bergauer T, Dragicevic M, et al.
    Phys Rev Lett, 2020 Oct 09;125(15):152001.
    PMID: 33095627 DOI: 10.1103/PhysRevLett.125.152001
    Using a data sample of proton-proton collisions at sqrt[s]=13  TeV, corresponding to an integrated luminosity of 140  fb^{-1} collected by the CMS experiment in 2016-2018, the B_{s}^{0}→X(3872)ϕ decay is observed. Decays into J/ψπ^{+}π^{-} and K^{+}K^{-} are used to reconstruct, respectively, the X(3872) and ϕ. The ratio of the product of branching fractions B[B_{s}^{0}→X(3872)ϕ]B[X(3872)→J/ψπ^{+}π^{-}] to the product B[B_{s}^{0}→ψ(2S)ϕ]B[ψ(2S)→J/ψπ^{+}π^{-}] is measured to be [2.21±0.29(stat)±0.17(syst)]%. The ratio B[B_{s}^{0}→X(3872)ϕ]/B[B^{0}→X(3872)K^{0}] is found to be consistent with one, while the ratio B[B_{s}^{0}→X(3872)ϕ]/B[B^{+}→X(3872)K^{+}] is two times smaller. This suggests a difference in the production dynamics of the X(3872) in B^{0} and B_{s}^{0} meson decays compared to B^{+}. The reported observation may shed new light on the nature of the X(3872) particle.
  9. Search for Leptoquarks Coupled to Third-Generation Quarks 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, 2018 Dec 14;121(24):241802.
    PMID: 30608761 DOI: 10.1103/PhysRevLett.121.241802
    Three of the most significant measured deviations from standard model predictions, the enhanced decay rate for B→D^{(*)}τν, hints of lepton universality violation in B→K^{(*)}ℓℓ decays, and the anomalous magnetic moment of the muon, can be explained by the existence of leptoquarks (LQs) with large couplings to third-generation quarks and masses at the TeV scale. The existence of these states can be probed at the LHC in high energy proton-proton collisions. A novel search is presented for pair production of LQs coupled to a top quark and a muon using data at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 35.9  fb^{-1}, recorded by the CMS experiment. No deviation from the standard model prediction has been observed and scalar LQs decaying exclusively into tμ are excluded up to masses of 1420 GeV. The results of this search are combined with those from previous searches for LQ decays into tτ and bν, which excluded scalar LQs below masses of 900 and 1080 GeV. Vector LQs are excluded up to masses of 1190 GeV for all possible combinations of branching fractions to tμ, tτ and bν. With this analysis, all relevant couplings of LQs with an electric charge of -1/3 to third-generation quarks are probed for the first time.
  10. Evidence for the Associated Production of a Single Top Quark and a Photon 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, 2018 Nov 30;121(22):221802.
    PMID: 30547617 DOI: 10.1103/PhysRevLett.121.221802
    The first evidence of events consistent with the production of a single top quark in association with a photon is reported. The analysis is based on proton-proton collisions at sqrt[s]=13  TeV and recorded by the CMS experiment in 2016, corresponding to an integrated luminosity of 35.9  fb^{-1}. Events are selected by requiring the presence of a muon (μ), a photon (γ), an imbalance in transverse momentum from an undetected neutrino (ν), and at least two jets (j) of which exactly one is identified as associated with the hadronization of a b quark. A multivariate discriminant based on topological and kinematic event properties is employed to separate signal from background processes. An excess above the background-only hypothesis is observed, with a significance of 4.4 standard deviations. A fiducial cross section is measured for isolated photons with transverse momentum greater than 25 GeV in the central region of the detector. The measured product of the cross section and branching fraction is σ(pp→tγj)B(t→μνb)=115±17(stat)±30(syst)  fb, which is consistent with the standard model prediction.
  11. Fulltext Search for supersymmetry in events with a photon, jets, b -jets, and missing transverse momentum in proton-proton collisions at 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):444.
    PMID: 31265003 DOI: 10.1140/epjc/s10052-019-6926-x
    A search for supersymmetry is presented based on events with at least one photon, jets, and large missing transverse momentum produced in proton-proton collisions at a center-of-mass energy of 13



    Te



    . The data correspond to an integrated luminosity of 35.9



    fb

    -
    1



    and were recorded at the LHC with the CMS detector in 2016. The analysis characterizes signal-like events by categorizing the data into various signal regions based on the number of jets, the number of
    b
    -tagged jets, and the missing transverse momentum. No significant excess of events is observed with respect to the expectations from standard model processes. Limits are placed on the gluino and top squark pair production cross sections using several simplified models of supersymmetric particle production with gauge-mediated supersymmetry breaking. Depending on the model and the mass of the next-to-lightest supersymmetric particle, the production of gluinos with masses as large as 2120



    Ge



    and the production of top squarks with masses as large as 1230



    Ge



    are excluded at 95% confidence level.
  12. Studies of Beauty Suppression via Nonprompt D^{0} Mesons in Pb-Pb 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, 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
  13. Observation of the Production of Three Massive Gauge Bosons at sqrt[s]=13  TeV
    Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Bergauer T, Dragicevic M, et al.
    Phys Rev Lett, 2020 Oct 09;125(15):151802.
    PMID: 33095594 DOI: 10.1103/PhysRevLett.125.151802
    The first observation is reported of the combined production of three massive gauge bosons (VVV with V=W, Z) in proton-proton collisions at a center-of-mass energy of 13 TeV. The analysis is based on a data sample recorded by the CMS experiment at the CERN LHC corresponding to an integrated luminosity of 137  fb^{-1}. The searches for individual WWW, WWZ, WZZ, and ZZZ production are performed in final states with three, four, five, and six leptons (electrons or muons), or with two same-sign leptons plus one or two jets. The observed (expected) significance of the combined VVV production signal is 5.7 (5.9) standard deviations and the corresponding measured cross section relative to the standard model prediction is 1.02_{-0.23}^{+0.26}. The significances of the individual WWW and WWZ production are 3.3 and 3.4 standard deviations, respectively. Measured production cross sections for the individual triboson processes are also reported.
  14. Evidence for Top Quark Production in Nucleus-Nucleus Collisions
    Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Bergauer T, Dragicevic M, et al.
    Phys Rev Lett, 2020 Nov 27;125(22):222001.
    PMID: 33315428 DOI: 10.1103/PhysRevLett.125.222001
    Ultrarelativistic heavy ion collisions recreate in the laboratory the thermodynamical conditions prevailing in the early universe up to 10^{-6}  sec, thereby allowing the study of the quark-gluon plasma (QGP), a state of quantum chromodynamics (QCD) matter with deconfined partons. The top quark, the heaviest elementary particle known, is accessible in nucleus-nucleus collisions at the CERN LHC, and constitutes a novel probe of the QGP. Here, we report the first evidence for the production of top quarks in nucleus-nucleus collisions, using lead-lead collision data at a nucleon-nucleon center-of-mass energy of 5.02 TeV recorded by the CMS experiment. Two methods are used to measure the cross section for top quark pair production (σ_{tt[over ¯]}) via the selection of charged leptons (electrons or muons) and bottom quarks. One method relies on the leptonic information alone, and the second one exploits, in addition, the presence of bottom quarks. The measured cross sections, σ_{tt[over ¯]}=2.54_{-0.74}^{+0.84} and 2.03_{-0.64}^{+0.71}  μb, respectively, are compatible with expectations from scaled proton-proton data and QCD predictions.
  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. Jet Shapes of Isolated Photon-Tagged Jets in Pb-Pb and pp 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, 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.
  17. Search for W Boson Decays to Three Charged Pions
    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.
  18. Search for Narrow Hγ Resonances 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 01;122(8):081804.
    PMID: 30932612 DOI: 10.1103/PhysRevLett.122.081804
    A search for heavy, narrow resonances decaying to a Higgs boson and a photon (Hγ) has been performed in proton-proton collision data at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 35.9  fb^{-1} collected with the CMS detector at the LHC in 2016. Events containing a photon and a Lorentz-boosted hadronically decaying Higgs boson reconstructed as a single, large-radius jet are considered, and the γ+jet invariant mass spectrum is analyzed for the presence of narrow resonances. To increase the sensitivity of the search, events are categorized depending on whether or not the large-radius jet can be identified as a result of the merging of two jets originating from b quarks. Results in both categories are found to agree with the predictions of the standard model. Upper limits on the production rate of Hγ resonances are set as a function of their mass in the range of 720-3250 GeV, representing the most stringent constraints to date.
  19. Search for Dark Matter Particles Produced in Association with a Top Quark Pair at sqrt[s]=13  TeV
    Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Asilar E, Bergauer T, et al.
    Phys Rev Lett, 2019 Jan 11;122(1):011803.
    PMID: 31012697 DOI: 10.1103/PhysRevLett.122.011803
    A search is performed for dark matter particles produced in association with a top quark pair in proton-proton collisions at sqrt[s]=13  TeV. The data correspond to an integrated luminosity of 35.9  fb^{-1} recorded by the CMS detector at the LHC. No significant excess over the standard model expectation is observed. The results are interpreted using simplified models of dark matter production via spin-0 mediators that couple to dark matter particles and to standard model quarks, providing constraints on the coupling strength between the mediator and the quarks. These are the most stringent collider limits to date for scalar mediators, and the most stringent for pseudoscalar mediators at low masses.
  20. Observation of Two Excited B_{c}^{+} States and Measurement of the B_{c}^{+}(2S) Mass in pp Collisions at sqrt[s]=13  TeV
    Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Bergauer T, Brandstetter J, et al.
    Phys Rev Lett, 2019 Apr 05;122(13):132001.
    PMID: 31012626 DOI: 10.1103/PhysRevLett.122.132001
    Signals consistent with the B_{c}^{+}(2S) and B_{c}^{*+}(2S) states are observed in proton-proton collisions at sqrt[s]=13  TeV, in an event sample corresponding to an integrated luminosity of 143  fb^{-1}, collected by the CMS experiment during the 2015-2018 LHC running periods. These excited b[over ¯]c states are observed in the B_{c}^{+}π^{+}π^{-} invariant mass spectrum, with the ground state B_{c}^{+} reconstructed through its decay to J/ψπ^{+}. The two states are reconstructed as two well-resolved peaks, separated in mass by 29.1±1.5(stat)±0.7(syst)  MeV. The observation of two peaks, rather than one, is established with a significance exceeding five standard deviations. The mass of the B_{c}^{+}(2S) meson is measured to be 6871.0±1.2(stat)±0.8(syst)±0.8(B_{c}^{+})  MeV, where the last term corresponds to the uncertainty in the world-average B_{c}^{+} mass.
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