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  1. Report of the forth Asian Prostate Cancer (A-CaP) study meeting
    Youl Lee J, Taniguchi T, Zhang K, Ng CF, Hakim L, Umbas R, et al.
    Jpn J Clin Oncol, 2019 Jun 01;49(6):581-586.
    PMID: 31141613 DOI: 10.1093/jjco/hyz053
    The Asian Prostate Cancer (A-CaP) Study is an Asia-wide prospective registry study for surveying the treatment outcome of prostate cancer patients who have received a histopathological diagnosis. The study aims to clarify the clinical situation for prostate cancer in Asia and use the outcomes for the purposes of international comparison. Following the first meeting in Tokyo on December 2015, the second meeting in Seoul, Korea 2016, the third meeting in Chiang Mai, Thailand, on October 2017, the fourth meeting was held in Seoul, again on August 2018 with the participation of members and collaborators from 13 countries and regions. In the meeting, participating countries and regions presented the current status of data collection and the A-CaP office presented a preliminary analysis of the registered cases received from each country and region. Participants discussed ongoing challenges relating to data cleaning and data up-dating which is the next step of the A-CaP study following the data collection phase between 2016 and 2018. There was specific difference in term of the patient characteristics, and initial treatment pattern among East Asia, Southeast Asia and Turkey, and Jordan. Finally, a close relationship between prevalence of PSA test and disease stage of the patients at diagnosis in Japan and Malaysia was discussed.
  2. Mainstreaming genetic counselling for genetic testing of BRCA1 and BRCA2 in ovarian cancer patients in Malaysia (MaGiC study)
    Yoon SYY, Ahmad Bashah NS, Wong SW, Mariapun S, Padmanabhan H, Hassan T, et al.
    Ann Oncol, 2018 Nov;29 Suppl 9:ix176.
    PMID: 32177935 DOI: 10.1093/annonc/mdy483.004
  3. Oncologist-led BRCA counselling improves access to cancer genetic testing in middle-income Asian country, with no significant impact on psychosocial outcomes
    Yoon SY, Wong SW, Lim J, Ahmad S, Mariapun S, Padmanabhan H, et al.
    J Med Genet, 2022 Mar;59(3):220-229.
    PMID: 33526602 DOI: 10.1136/jmedgenet-2020-107416
    BACKGROUND: Identifying patients with BRCA mutations is clinically important to inform on the potential response to treatment and for risk management of patients and their relatives. However, traditional referral routes may not meet clinical needs, and therefore, mainstreaming cancer genetics has been shown to be effective in some high-income and high health-literacy settings. To date, no study has reported on the feasibility of mainstreaming in low-income and middle-income settings, where the service considerations and health literacy could detrimentally affect the feasibility of mainstreaming.

    METHODS: The Mainstreaming Genetic Counselling for Ovarian Cancer Patients (MaGiC) study is a prospective, two-arm observational study comparing oncologist-led and genetics-led counselling. This study included 790 multiethnic patients with ovarian cancer from 23 sites in Malaysia. We compared the impact of different method of delivery of genetic counselling on the uptake of genetic testing and assessed the feasibility, knowledge and satisfaction of patients with ovarian cancer.

    RESULTS: Oncologists were satisfied with the mainstreaming experience, with 95% indicating a desire to incorporate testing into their clinical practice. The uptake of genetic testing was similar in the mainstreaming and genetics arm (80% and 79%, respectively). Patient satisfaction was high, whereas decision conflict and psychological impact were low in both arms of the study. Notably, decisional conflict, although lower than threshold, was higher for the mainstreaming group compared with the genetics arm. Overall, 13.5% of patients had a pathogenic variant in BRCA1 or BRCA2, and there was no difference between psychosocial measures for carriers in both arms.

    CONCLUSION: The MaGiC study demonstrates that mainstreaming cancer genetics is feasible in low-resource and middle-resource Asian setting and increased coverage for genetic testing.

  4. Fulltext Predictive factors of prostate cancer diagnosis with PSA 4.0-10.0 ng/ml in a multi-ethnic Asian population, Malaysia
    Yii RSL, Lim J, Sothilingam S, Yeoh WS, Fadzli AN, Ong TA, et al.
    Asian J Surg, 2020 Jan;43(1):87-94.
    PMID: 30962017 DOI: 10.1016/j.asjsur.2019.02.014
    OBJECTIVES: To identify the associated factors determining prostate cancer detection using transrectal ultrasound (TRUS)-guided prostate biopsy, within a multi-ethnic Malaysian population with prostate specific antigen (PSA) between 4.0 and 10.0 ng/ml.

    METHODS: Study subjects included men with initial PSA between 4.0 and 10.0 ng/ml that have undergone 12-core TRUS-guided prostate biopsy between 2009 and 2016. The prostate cancer detection rate was calculated, while potential factors associated with detection were investigated via univariable and multivariable analysis.

    RESULTS: A total of 617 men from a multi-ethnic background encompassing Chinese (63.5%), Malay (23.1%) and Indian (13.3%) were studied. The overall cancer detection rate was 14.3% (88/617), which included cancers detected at biopsy 1 (first biopsy), biopsy 2 (second biopsy with previous negative biopsy) and biopsy ≥ 3 (third or more biopsies with prior negative biopsies). Indian men displayed higher detection rate (23.2%) and increased risk of prostate cancer development (OR 1.85, 95% CI 1.03-3.32, p 

  5. Electrosteric stabilization and its role in cooperative magnetophoresis of colloidal magnetic nanoparticles
    Yeap SP, Ahmad AL, Ooi BS, Lim J
    Langmuir, 2012 Oct 23;28(42):14878-91.
    PMID: 23025323 DOI: 10.1021/la303169g
    A detailed study on the conflicting role that colloid stability plays in magnetophoresis is presented. Magnetic iron oxide particles (MIOPs) that were sterically stabilized via surface modification with poly(sodium 4-styrene sulfonate) of different molecular weights (i.e., 70 and 1000 kDa) were employed as our model system. Both sedimentation kinetics and quartz crystal microbalance with dissipation (QCM-D) measurements suggested that PSS 70 kDa is a better stabilizer as compared to PSS 1000 kDa. This observation is mostly attributed to the bridging flocculation of PSS 1000 kDa decorated MIOPs originated from the extended polymeric conformation layer. Later, a lab-scale high gradient magnetic separation (HGMS) device was designed to study the magnetophoretic collection of MIOPs. Our experimental results revealed that the more colloidally stable the MIOP suspension is, the harder it is to be magnetically isolated by HGMS. At 50 mg/L, naked MIOPs without coating can be easily captured by HGMS at separation efficiency up to 96.9 ± 2.6%. However, the degree of separation dropped quite drastically to 83.1 ± 1.2% and 67.7 ± 4.6%, for MIOPs with PSS 1000k and PSS 70k coating, respectively. This observation clearly implies that polyelectrolyte coating that was usually employed to electrosterically stabilize a colloidal system in turn compromises the magnetic isolation efficiency. By artificially destroying the colloidal stability of the MIOPs with ionic strength increment, the ability for HGMS to recover the most stable suspension (i.e., PSS 70k-coated MIOPs) increased to >86% at 100 mM monovalent ion (Na(+)) or at 10 mM divalent ion (Ca(2+)). This observation has verified the conflicting role of colloidal stability in magnetophoretic separation.
  6. Fulltext Prophylactic antibiotics in orthopaedic surgery: guidelines and practice
    Yeap JS, Lim JW, Vergis M, Au Yeung PS, Chiu CK, Singh H
    Med J Malaysia, 2006 Jun;61(2):181-8.
    PMID: 16898309
    The national clinical practice guideline has recommended that prophylactic antibiotic be given in orthopaedic surgery involving joint replacements and internal fixation of fractures. The aim of this study is to assess the current antibiotics prophylaxis practice in a state level hospital. One hundred and three patients (68 males, 35 females; mean age 41.6 +/- 22.2 years) undergoing internal fixation for closed fractures and joint replacement surgery were included in this prospective study. The choice of pre and post-operative antibiotics, their dosages and duration of administration were recorded. The pre-operative antibiotics were only deemed to have been given if it was documented in the case notes and in the case of post-operative antibiotics if it was signed on the drug chart. Eighty eight percent were given pre-operative prophylactic antibiotics and 92% were given post-operative antibiotics. For patients undergoing internal fixation of fractures, the most commonly used antibiotic for both pre and post-op is intravenous cefuroxime. For joint replacement surgery, the most commonly used antibiotic is intravenous cefoperazone. The duration or number of doses of post-operative antibiotics was highly variable. It was not stated in 56% of the post-operative instructions. Post-operative antibiotic was ordered for 48 hours or longer in 10%. In conclusion, prophylactic antibiotics appear to be widely practised. The first line antibiotics as recommended by the present guideline were not given in any of the patients. Second generation followed by third generation cephalosporins are the most popular antibiotics, with a trend towards using third generation cephalosporins in arthroplasty patients. Single dose prophylaxis was rarely practised.
  7. Fulltext Detection of Prostate Cancer via IR Spectroscopic Analysis of Urinary Extracellular Vesicles: A Pilot Study
    Yap XL, Wood B, Ong TA, Lim J, Goh BH, Lee WL
    Membranes (Basel), 2021 Jul 31;11(8).
    PMID: 34436354 DOI: 10.3390/membranes11080591
    Extracellular vesicles (EVs) are membranous nanoparticles naturally released from living cells which can be found in all types of body fluids. Recent studies found that cancer cells secreted EVs containing the unique set of biomolecules, which give rise to a distinctive absorbance spectrum representing its cancer type. In this study, we aimed to detect the medium EVs (200-300 nm) from the urine of prostate cancer patients using Fourier transform infrared (FTIR) spectroscopy and determine their association with cancer progression. EVs extracted from 53 urine samples from patients suspected of prostate cancer were analyzed and their FTIR spectra were preprocessed for analysis. Characterization of morphology, particle size and marker proteins confirmed that EVs were successfully isolated from urine samples. Principal component analysis (PCA) of the EV's spectra showed the model could discriminate prostate cancer with a sensitivity of 59% and a specificity of 81%. The area under curve (AUC) of FTIR PCA model for prostate cancer detection in the cases with 4-20 ng/mL PSA was 0.7, while the AUC for PSA alone was 0.437, suggesting the analysis of urinary EVs described in this study may offer a novel strategy for the development of a noninvasive additional test for prostate cancer screening.
  8. Adverse metabolic consequences of androgen deprivation therapy (ADT) on Asian patients with prostate cancer: Primary results from the real-life experience of ADT in Asia (READT) study
    Wong CHM, Xu N, Lim J, Feng KK, Chan WKW, Chan MTY, et al.
    Prostate, 2023 Jun;83(8):801-808.
    PMID: 36938957 DOI: 10.1002/pros.24519
    BACKGROUND: Androgen deprivation therapy (ADT) use in prostate cancer (PCa) has seen a rising trend. We investigated the relationship between ADT and adverse changes in metabolic parameters in an Asian population.

    METHODS: This is an international prospective multicenter single-arm cohort yielded from the real-life experience of ADT in Asia (READT) registry. Consecutive ADT-naïve patients diagnosed of PCa and started on ADT were prospectively recruited from 2016 and analyzed. Baseline patient characteristics, PCa disease status, and metabolic parameters were documented. Patients were followed up at 6-month interval for up to 5 years. Metabolic parameters including body weight, lipid profiles, and glycemic profiles were recorded and analyzed.

    RESULTS: 589 patients were eligible for analysis. ADT was associated with adverse glycemic profiles, being notable at 6 months upon ADT initiation and persisted beyond 1 year. Comparing to baseline, fasting glucose level and hemoglobin A1c level increased by 4.8% (p 

  9. Fulltext Inherited mutations in BRCA1 and BRCA2 in an unselected multiethnic cohort of Asian patients with breast cancer and healthy controls from Malaysia
    Wen WX, Allen J, Lai KN, Mariapun S, Hasan SN, Ng PS, et al.
    J Med Genet, 2018 02;55(2):97-103.
    PMID: 28993434 DOI: 10.1136/jmedgenet-2017-104947
    BACKGROUND: Genetic testing for BRCA1 and BRCA2 is offered typically to selected women based on age of onset and family history of cancer. However, current internationally accepted genetic testing referral guidelines are built mostly on data from cancer genetics clinics in women of European descent. To evaluate the appropriateness of such guidelines in Asians, we have determined the prevalence of germ line variants in an unselected cohort of Asian patients with breast cancer and healthy controls.

    METHODS: Germ line DNA from a hospital-based study of 2575 unselected patients with breast cancer and 2809 healthy controls were subjected to amplicon-based targeted sequencing of exonic and proximal splice site junction regions of BRCA1 and BRCA2 using the Fluidigm Access Array system, with sequencing conducted on a Illumina HiSeq2500 platform. Variant calling was performed with GATK UnifiedGenotyper and were validated by Sanger sequencing.

    RESULTS: Fifty-five (2.1%) BRCA1 and 66 (2.6%) BRCA2 deleterious mutations were identified among patients with breast cancer and five (0.18%) BRCA1 and six (0.21%) BRCA2 mutations among controls. One thousand one hundred and eighty-six (46%) patients and 97 (80%) carriers fulfilled the National Comprehensive Cancer Network guidelines for genetic testing.

    CONCLUSION: Five per cent of unselected Asian patients with breast cancer carry deleterious variants in BRCA1 or BRCA2. While current referral guidelines identified the majority of carriers, one in two patients would be referred for genetic services. Given that such services are largely unavailable in majority of low-resource settings in Asia, our study highlights the need for more efficient guidelines to identify at-risk individuals in Asia.

  10. Fulltext Characterizing prostate cancer risk through multi-ancestry genome-wide discovery of 187 novel risk variants
    Wang A, Shen J, Rodriguez AA, Saunders EJ, Chen F, Janivara R, et al.
    Nat Genet, 2023 Dec;55(12):2065-2074.
    PMID: 37945903 DOI: 10.1038/s41588-023-01534-4
    The transferability and clinical value of genetic risk scores (GRSs) across populations remain limited due to an imbalance in genetic studies across ancestrally diverse populations. Here we conducted a multi-ancestry genome-wide association study of 156,319 prostate cancer cases and 788,443 controls of European, African, Asian and Hispanic men, reflecting a 57% increase in the number of non-European cases over previous prostate cancer genome-wide association studies. We identified 187 novel risk variants for prostate cancer, increasing the total number of risk variants to 451. An externally replicated multi-ancestry GRS was associated with risk that ranged from 1.8 (per standard deviation) in African ancestry men to 2.2 in European ancestry men. The GRS was associated with a greater risk of aggressive versus non-aggressive disease in men of African ancestry (P = 0.03). Our study presents novel prostate cancer susceptibility loci and a GRS with effective risk stratification across ancestry groups.
  11. Progress toward universal health coverage in ASEAN
    Van Minh H, Pocock NS, Chaiyakunapruk N, Chhorvann C, Duc HA, Hanvoravongchai P, et al.
    Glob Health Action, 2014 Dec;7(1):25856.
    PMID: 28672540 DOI: 10.3402/gha.v7.25856
    Background The Association of Southeast Asian Nations (ASEAN) is characterized by much diversity in terms of geography, society, economic development, and health outcomes. The health systems as well as healthcare structure and provisions vary considerably. Consequently, the progress toward Universal Health Coverage (UHC) in these countries also varies. This paper aims to describe the progress toward UHC in the ASEAN countries and discuss how regional integration could influence UHC. Design Data reported in this paper were obtained from published literature, reports, and gray literature available in the ASEAN countries. We used both online and manual search methods to gather the information and 'snowball' further data. Results We found that, in general, ASEAN countries have made good progress toward UHC, partly due to relatively sustained political commitments to endorse UHC in these countries. However, all the countries in ASEAN are facing several common barriers to achieving UHC, namely 1) financial constraints, including low levels of overall and government spending on health; 2) supply side constraints, including inadequate numbers and densities of health workers; and 3) the ongoing epidemiological transition at different stages characterized by increasing burdens of non-communicable diseases, persisting infectious diseases, and reemergence of potentially pandemic infectious diseases. The ASEAN Economic Community's (AEC) goal of regional economic integration and a single market by 2015 presents both opportunities and challenges for UHC. Healthcare services have become more available but health and healthcare inequities will likely worsen as better-off citizens of member states might receive more benefits from the liberalization of trade policy in health, either via regional outmigration of health workers or intra-country health worker movement toward private hospitals, which tend to be located in urban areas. For ASEAN countries, UHC should be explicitly considered to mitigate deleterious effects of economic integration. Political commitments to safeguard health budgets and increase health spending will be necessary given liberalization's risks to health equity as well as migration and population aging which will increase demand on health systems. There is potential to organize select health services regionally to improve further efficiency. Conclusions We believe that ASEAN has significant potential to become a force for better health in the region. We hope that all ASEAN citizens can enjoy higher health and safety standards, comprehensive social protection, and improved health status. We believe economic and other integration efforts can further these aspirations.
  12. 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 .
  13. Measurements of the Electroweak Diboson Production Cross Sections in Proton-Proton Collisions at sqrt[s]=5.02  TeV Using Leptonic Decays
    Tumasyan A, Adam W, Andrejkovic JW, Bergauer T, Chatterjee S, Dragicevic M, et al.
    Phys Rev Lett, 2021 Nov 05;127(19):191801.
    PMID: 34797136 DOI: 10.1103/PhysRevLett.127.191801
    The first measurements of diboson production cross sections in proton-proton interactions at a center-of-mass energy of 5.02 TeV are reported. They are based on data collected with the CMS detector at the LHC, corresponding to an integrated luminosity of 302  pb^{-1}. Events with two, three, or four charged light leptons (electrons or muons) in the final state are analyzed. The WW, WZ, and ZZ total cross sections are measured as σ_{WW}=37.0_{-5.2}^{+5.5}(stat)_{-2.6}^{+2.7}(syst)  pb, σ_{WZ}=6.4_{-2.1}^{+2.5}(stat)_{-0.3}^{+0.5}(syst)  pb, and σ_{ZZ}=5.3_{-2.1}^{+2.5}(stat)_{-0.4}^{+0.5}(syst)  pb. All measurements are in good agreement with theoretical calculations at combined next-to-next-to-leading order quantum chromodynamics and next-to-leading order electroweak accuracy.
  14. Search for Long-Lived Particles Decaying in the CMS End Cap Muon Detectors in Proton-Proton Collisions at sqrt[s]=13  TeV
    Tumasyan A, Adam W, Andrejkovic JW, Bergauer T, Chatterjee S, Dragicevic M, et al.
    Phys Rev Lett, 2021 Dec 24;127(26):261804.
    PMID: 35029469 DOI: 10.1103/PhysRevLett.127.261804
    A search for long-lived particles (LLPs) produced in decays of standard model (SM) Higgs bosons is presented. The data sample consists of 137  fb^{-1} of proton-proton collisions at sqrt[s]=13  TeV, recorded at the LHC in 2016-2018. A novel technique is employed to reconstruct decays of LLPs in the end cap muon detectors. The search is sensitive to a broad range of LLP decay modes and to masses as low as a few GeV. No excess of events above the SM background is observed. The most stringent limits to date on the branching fraction of the Higgs boson to LLPs subsequently decaying to quarks and τ^{+}τ^{-} are found for proper decay lengths greater than 6, 20, and 40 m, for LLP masses of 7, 15, and 40 GeV, respectively.
  15. Measurement of the Dependence of the Hadron Production Fraction Ratios f_{s}/f_{u} and f_{d}/f_{u} on B Meson Kinematic Variables in Proton-Proton Collisions at sqrt[s]=13  TeV
    Tumasyan A, Adam W, Andrejkovic JW, Bergauer T, Chatterjee S, Damanakis K, et al.
    Phys Rev Lett, 2023 Sep 22;131(12):121901.
    PMID: 37802954 DOI: 10.1103/PhysRevLett.131.121901
    The dependence of the ratio between the B_{s}^{0} and B^{+} hadron production fractions, f_{s}/f_{u}, on the transverse momentum (p_{T}) and rapidity of the B mesons is studied using the decay channels B_{s}^{0}→J/ψϕ and B^{+}→J/ψK^{+}. The analysis uses a data sample of proton-proton collisions at a center-of-mass energy of 13 TeV, collected by the CMS experiment in 2018 and corresponding to an integrated luminosity of 61.6  fb^{-1}. The f_{s}/f_{u} ratio is observed to depend on the B p_{T} and to be consistent with becoming asymptotically constant at large p_{T}. No rapidity dependence is observed. The ratio of the B^{0} to B^{+} meson production fractions, f_{d}/f_{u}, is also measured, for the first time in proton-proton collisions, using the B^{0}→J/ψK^{*0} decay channel. The result is found to be within 1 standard deviation of unity and independent of p_{T} and rapidity, as expected from isospin invariance.
  16. Observation of τ Lepton Pair Production in Ultraperipheral Pb-Pb Collisions at sqrt[s_{NN}]=5.02  TeV
    Tumasyan A, Adam W, Andrejkovic JW, Bergauer T, Chatterjee S, Damanakis K, et al.
    Phys Rev Lett, 2023 Oct 13;131(15):151803.
    PMID: 37897747 DOI: 10.1103/PhysRevLett.131.151803
    We present an observation of photon-photon production of τ lepton pairs in ultraperipheral lead-lead collisions. The measurement is based on a data sample with an integrated luminosity of 404  μb^{-1} collected by the CMS experiment at a center-of-mass energy per nucleon pair of sqrt[s_{NN}]=5.02  TeV. The γγ→τ^{+}τ^{-} process is observed for τ^{+}τ^{-} events with a muon and three charged hadrons in the final state. The measured fiducial cross section is σ(γγ→τ^{+}τ^{-})=4.8±0.6(stat)±0.5(syst)  μb, where the second (third) term corresponds to the statistical (systematic) uncertainty in σ(γγ→τ^{+}τ^{-}) in agreement with leading-order QED predictions. Using σ(γγ→τ^{+}τ^{-}), we estimate a model-dependent value of the anomalous magnetic moment of the τ lepton of a_{τ}=0.001_{-0.089}^{+0.055}.
  17. Probing Heavy Majorana Neutrinos and the Weinberg Operator through Vector Boson Fusion Processes in Proton-Proton Collisions at sqrt[s]=13  TeV
    Tumasyan A, Adam W, Andrejkovic JW, Bergauer T, Chatterjee S, Damanakis K, et al.
    Phys Rev Lett, 2023 Jul 07;131(1):011803.
    PMID: 37478454 DOI: 10.1103/PhysRevLett.131.011803
    The first search exploiting the vector boson fusion process to probe heavy Majorana neutrinos and the Weinberg operator at the LHC is presented. The search is performed in the same-sign dimuon final state using a proton-proton collision dataset recorded at sqrt[s]=13  TeV, collected with the CMS detector and corresponding to a total integrated luminosity of 138  fb^{-1}. The results are found to agree with the predictions of the standard model. For heavy Majorana neutrinos, constraints on the squared mixing element between the muon and the heavy neutrino are derived in the heavy neutrino mass range 50 GeV-25 TeV; for masses above 650 GeV these are the most stringent constraints from searches at the LHC to date. A first test of the Weinberg operator at colliders provides an observed upper limit at 95% confidence level on the effective μμ Majorana neutrino mass of 10.8 GeV.
  18. Search for Higgs Boson Decay to a Charm Quark-Antiquark Pair in Proton-Proton Collisions at sqrt[s]=13  TeV
    Tumasyan A, Adam W, Andrejkovic JW, Bergauer T, Chatterjee S, Damanakis K, et al.
    Phys Rev Lett, 2023 Aug 11;131(6):061801.
    PMID: 37625071 DOI: 10.1103/PhysRevLett.131.061801
    A search for the standard model Higgs boson decaying to a charm quark-antiquark pair, H→cc[over ¯], produced in association with a leptonically decaying V (W or Z) boson is presented. The search is performed with proton-proton collisions at sqrt[s]=13  TeV collected by the CMS experiment, corresponding to an integrated luminosity of 138  fb^{-1}. Novel charm jet identification and analysis methods using machine learning techniques are employed. The analysis is validated by searching for Z→cc[over ¯] in VZ events, leading to its first observation at a hadron collider with a significance of 5.7 standard deviations. The observed (expected) upper limit on σ(VH)B(H→cc[over ¯]) is 0.94 (0.50_{-0.15}^{+0.22})pb at 95% confidence level (C.L.), corresponding to 14 (7.6_{-2.3}^{+3.4}) times the standard model prediction. For the Higgs-charm Yukawa coupling modifier, κ_{c}, the observed (expected) 95% C.L. interval is 1.1
  19. 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.
  20. Search for Nonresonant Pair Production of Highly Energetic Higgs Bosons Decaying to Bottom Quarks
    Tumasyan A, Adam W, Andrejkovic JW, Bergauer T, Chatterjee S, Damanakis K, et al.
    Phys Rev Lett, 2023 Jul 28;131(4):041803.
    PMID: 37566864 DOI: 10.1103/PhysRevLett.131.041803
    A search for nonresonant Higgs boson (H) pair production via gluon and vector boson (V) fusion is performed in the four-bottom-quark final state, using proton-proton collision data at 13 TeV corresponding to 138  fb^{-1} collected by the CMS experiment at the LHC. The analysis targets Lorentz-boosted H pairs identified using a graph neural network. It constrains the strengths relative to the standard model of the H self-coupling and the quartic VVHH couplings, κ_{2V}, excluding κ_{2V}=0 for the first time, with a significance of 6.3 standard deviations when other H couplings are fixed to their standard model values.
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