Displaying publications 1 - 20 of 26 in total

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  1. Kevin-Tey WF, Wen WX, Bee PC, Eng HS, Ho KW, Tan SM, et al.
    Hum Immunol, 2023 Mar;84(3):172-185.
    PMID: 36517321 DOI: 10.1016/j.humimm.2022.11.006
    Killer cell immunoglobulin-like receptors (KIR) genotype and haplotype frequencies have been reported to vary distinctly between populations, which in turn contributes to variation in the alloreactivity of natural killer (NK) cells. Utilizing the diverse KIR genes to identify suitable transplant donors would prove challenging in multi-ethnic countries, even more in resource-limited countries where KIR genotyping has not been established. In this study, we determined the KIR genotypes from 124 unrelated Malaysians consisting of the Malays, Chinese, Indians, and aboriginal people through polymerase chain reaction sequence-specific primer (PCR-SSP) genotyping and employing an expectation-maximization (EM) algorithm to assign haplotypes based on pre-established reference haplotypes. A total of 27 distinct KIR haplotypes were discerned with higher frequencies of haplotype A (55.2%) than haplotype B (44.8%). The most frequent haplotypes were cA01:tA01 (55.2%), cB01:tB01 (18.1%), and cB02:tA01 (13.3%), while the least frequent haplotypes were cB03:tB01 (1.2%), cB04:tB03 (0.4%), and cB03:tA01 (0.4%). Several haplotypes were identified to be unique to a specific ethnic group. The genotype with the highest frequency was genotype AB (71.8%), followed by AA (19.4%), and BB (8.9%). The Indians exhibited the lowest genotype AA but the highest genotype BB, whereas genotype BB was absent in the aboriginal people. Despite the limitations, the genotype and haplotypes in the Malaysian population were successfully highlighted. The identification of ethnic-specific KIR genotypes and haplotypes provides the first step to utilizing KIR in identifying suitable transplant donors to further improve the transplant outcome in the Malaysian population.
  2. Lim HP, Ng SD, Dasa DB, Adnan SA, Tey BT, Chan ES, et al.
    Int J Biol Macromol, 2023 Mar 31;232:123461.
    PMID: 36720328 DOI: 10.1016/j.ijbiomac.2023.123461
    Formulation of water-in-oil (W/O) Pickering emulsion (PE) for food applications has been largely restricted by the limited choices of food-grade Pickering emulsifiers. In this study, composite microgels made of chitosan and carrageenan were explored as a dual (pH and thermal) stimuli-responsive Pickering emulsifier for the stabilization of W/O PE. The chitosan-carrageenan (CS-CRG) composite microgels not only exhibited pH- and thermo-responsiveness, but also displayed enhanced lipophilicity as compared to the discrete polymers. The stability of the CS-CRG-stabilized W/O PE system (CS-CRG PE) was governed by CS:CRG mass ratio and oil fractions used. The CS-CRG PE remained stable at acidic pH and at temperatures below 40 °C. The instability of CS-CRG composite microgels at alkaline pH and at temperatures above 40 °C rendered the demulsification of CS-CRG PE. This stimuli-responsive W/O PE could unlock new opportunities for the development of stimuli-responsive W/O PE using food-grade materials.
  3. Liam CCK, Boo YL, Lee YL, Law KB, Ho KW, Shahnaz SAKS, et al.
    Blood Cell Ther, 2021 Feb 25;4(1):1-8.
    PMID: 36712843 DOI: 10.31547/bct-2020-009
    BACKGROUND: Multiple Myeloma (MM) is characterized by the presence of clonal plasma cells. These often result in complications including bone destruction, hypercalcemia, renal insufficiency, and anaemia. Induction with a triplet or quadruplet regimen followed by autologous stem cell transplantation (ASCT) has been the standard of care for transplant eligible patients to achieve durable remission.

    PURPOSE: This is a retrospective analytical study to determine the outcome of Multiple Myeloma patients who underwent ASCT in Ampang Hospital.

    MATERIALS AND METHODS: We included a 5-year cohort of patients transplanted from 1st July 2014 to 30th June 2019. Data were obtained through electronic medical records. Prognostic factors for progression-free survival (PFS) and overall survival (OS) were analyzed using simple and multiple Cox proportional hazard regression analysis. All analyses were done using software R version 3.6.2 with validated statistical packages.

    RESULTS: 139 patients were analyzed. The median age at transplant was 56 years old and 56.1% are males (n=78). The most common subtype is IgG Kappa (n=67, 48.2%). Only 93 patients in which the International Staging System (ISS) could be determined, and among them, 33.3% of patients (n=31) have advanced stage Ⅲ disease. The most common induction received before ASCT was a bortezomib based regimen and/or an immunomodulatory (IMiD) based regimen. 63.3% of patients achieved at least a very good partial response (VGPR) before ASCT. Most patients received myeloablative conditioning (MAC) (n=119, 85.6%). The mean cell dose is 3.68×106/kg. The median time to engraftment was 11 days for both platelet and absolute neutrophil count (ANC). With the median follow-up of 17.3 (range, 6.2-33.4) months, the median OS and PFS were not reached. The 1-year and 2-year PFS were 75% (95% CI 66-82%) and 52% (95% CI 42-62%), respectively. The 1-year and 2-year OS were 82% (95% CI 74-88%) and 70% (95% CI 60-78%), respectively. 6 patients (4.3%) had transplant-related mortality (TRM). IgA subtype was found to adversely affect PFS. Maintenance therapy and the absence of renal impairment was associated with better PFS and OS.

    DISCUSSION AND CONCLUSIONS: Our study found that ASCT following induction treatment is safe and beneficial to achieve a deeper remission status. In our study, the addition of maintenance therapy is associated with an improved outcome in PFS and OS.

  4. Tay EL, Hayashida K, Chen M, Yin WH, Park DW, Seth A, et al.
    J Card Surg, 2020 Sep;35(9):2142-2146.
    PMID: 32720374 DOI: 10.1111/jocs.14722
    OBJECTIVES: The impact of the COVID-19 pandemic on the treatment of patient with aortic valve stenosis is unknown and there is uncertainty on the optimal strategies in managing these patients.

    METHODS: This study is supported and endorsed by the Asia Pacific Society of Interventional Cardiology. Due to the inability to have face to face discussions during the pandemic, an online survey was performed by inviting key opinion leaders (cardiac surgeon/interventional cardiologist/echocardiologist) in the field of transcatheter aortic valve implantation (TAVI) in Asia to participate. The answers to a series of questions pertaining to the impact of COVID-19 on TAVI were collected and analyzed. These led subsequently to an expert consensus recommendation on the conduct of TAVI during the pandemic.

    RESULTS: The COVID-19 pandemic had resulted in a 25% (10-80) reduction of case volume and 53% of operators required triaging to manage their patients with severe aortic stenosis. The two most important parameters used to triage were symptoms and valve area. Periprocedural changes included the introduction of teleconsultation, preprocedure COVID-19 testing, optimization of protests, and catheterization laboratory set up. In addition, length of stay was reduced from a mean of 4.4 to 4 days.

    CONCLUSION: The COVID-19 pandemic has impacted on the delivery of TAVI services to patients in Asia. This expert recommendation on best practices may be a useful guide to help TAVI teams during this period until a COVID-19 vaccine becomes widely available.

  5. Chiam PTL, Hayashida K, Watanabe Y, Yin WH, Kao HL, Lee MKY, et al.
    Open Heart, 2021 01;8(1).
    PMID: 33419935 DOI: 10.1136/openhrt-2020-001541
    OBJECTIVES: Transcatheter aortic valve replacement (TAVR) is increasingly performed. Physically small Asians have smaller aortic root and peripheral vessel anatomy. The influence of gender of Asian patients undergoing TAVR is unknown and may affect outcomes. The aim of this study was to assess sex differences in Asian patients undergoing TAVR.

    METHODS: Patients undergoing TAVR from eight countries were enrolled. In this retrospective analysis, we examined differences in characteristics, 30-day clinical outcomes and 1-year survival between female and male Asian patients.

    RESULTS: Eight hundred and seventy-three patients (54.4% women) were included. Women were older, smaller and had less coronary artery and lung disease but tended to have higher logistic EuroSCOREs. Smaller prostheses were used more often in women. Major vascular complications occurred more frequently in women (5.5% vs 1.8%, p<0.01); however, 30-day stroke and mortality (women vs men: 1.5% vs 1.6%, p=0.95% and 4.3% vs 3.4%, p=0.48) were similar. Functional status improvement was significant and comparable between the sexes. Conduction disturbance and permanent pacemaker requirements (11.2% vs 9.0%, p=0.52) were also similar as was 1-year survival (women vs men: 85.6% vs 88.2%, p=0.25). The only predictors of 30-day mortality were major vascular injury in women and age in men.

    CONCLUSIONS: Asian women had significantly smaller stature and anatomy with some differences in clinical profiles. Despite more frequent major vascular complications, women had similar 30-day stroke or mortality rates. Functional status improvement was significant and comparable between the sexes. Conduction disturbance and permanent pacemaker requirements were similar as was 1-year survival.

  6. Iida M, Dodds A, Akter M, Srivastava A, Moon JH, Dung PC, et al.
    Blood Cell Ther, 2021 May 25;4(2):20-28.
    PMID: 36712901 DOI: 10.31547/bct-2020-013
    This report describes the results of the Asia-Pacific Blood and Marrow Transplantation Group (APBMT) Activity Survey 2016, focusing on the trends of haploidentical and cord blood (CB) transplants in the Asia-Pacific region. Mongolia and Nepal submitted their first activity data in this survey, and the number of countries/regions participating in the activity survey grew to 20. The annual number of transplants exceeded 20,000 for the first time in 2016, and the total number of centers increased to 686. About 87.9% of all hematopoietic stem cell transplantations (HSCTs) were performed in China, Japan, Korea, India, and Australia with China performing the highest number. Beginning with the 2016 survey, APBMT modified the survey forms and initiated the collection of the exact number of haploidentical transplants. The total number of such transplants was 3,871, and 66.0% of those were performed in China. Meanwhile, cord blood transplants in this region remained high (1,612), and 81.8% of them (1,319) were performed in Japan. The number of facilities and transplants, the ratio of haploidentical transplants to related transplants, the ratio of CB transplants to unrelated transplants, and proportions of haploidentical and CB transplants per capita significantly differed among countries/regions in the Asia-Pacific region. Data collection and analysis revealed the transition and diversity of transplants in this region. This report also shows a dramatic increase in haploidentical transplants as seen in other parts of the world, while revealing uniquely that the activity of cord blood transplant remains high in this region.
  7. Iida M, Liu K, Huang XJ, Depei W, Kuwatsuka Y, Moon JH, et al.
    Blood Cell Ther, 2022 Nov 25;5(4):87-98.
    PMID: 36713681 DOI: 10.31547/bct-2022-002
    The Asia-Pacific Blood and Marrow Transplantation Group (APBMT) has been conducting annual surveys on the activity of hematopoietic stem cell transplants since 2007. The APBMT Data Center collected the following data in 2017. A total of 21,504 transplants were registered from 733 transplant centers of 20 countries/regions in the Asia-Pacific (AP) region. Five countries/regions comprised 89.4% of all transplants - China (6,979), Japan (5,794), South Korea (2,626), India (2,034), and Australia (1,789). The number of centers in these five countries/regions also comprised 88.9% of all centers: Japan (373), China (123), India (66), Australia (45), and South Korea (44). The overall ratio between autologous and allogeneic transplants was 37.0% and 63.0%, respectively, but the ratios varied significantly among countries/regions. Autologous transplants have surpassed allogeneic transplants in Thailand, Australia, Vietnam, New Zealand, Singapore, and Iran. In contrast, the proportion of allogeneic transplants comprised over 70% of all transplants in Pakistan, China, and Hong Kong. These ratios were compared by the Data Center among countries/regions that performed more than 50 transplants. The proportion of related and unrelated transplants also differed among countries/regions. The number of unrelated transplants was more than related ones in Japan (2,551 vs. 1,202) and Australia (329 vs. 291), whereas more than 80% of all transplants were related transplants in Malaysia (90.9%), India (89.5%), Iran (87.2%), Vietnam (85.7%), China (80.9%), and Thailand (80.6%). All transplant activities were related transplants in Pakistan, the Philippines, Myanmar, and Nepal, and no allogeneic transplants were performed in Bangladesh and Mongolia. Regarding the indications for transplants, acute myeloid leukemia (AML) was the most common disease for allogeneic transplant (4,759, 35.1% of allogeneic transplants), while plasma cell disorder (PCD) was the most common disease for autologous transplant (3,701, 27.3% of all autologous transplants). Furthermore, the number of transplants for hemoglobinopathy has steeply increased in this region compared with the rest of disease indications (677, 3.1% of all transplants). APBMT covers a broad area globally, including countries/regions with diverse disease distribution, development of HSCT programs, population, and economic power. Consistent and continuous activity surveys considering those elements in each country/region revealed the HSCT field's diverse characteristics and background factors in this region.
  8. Iida M, Liu K, Huang XJ, Huang H, Kuwatsuka Y, Moon JH, et al.
    Blood Cell Ther, 2023 Nov 25;6(4):114-123.
    PMID: 38149021 DOI: 10.31547/bct-2023-015
    The number of hematopoietic stem cell transplantations (HCTs) is increasing annually worldwide, and the Asia-Pacific (AP) region is no exception. We report on the absolute number of HCTs in 2018 and 2019 and the trends in graft selection and disease indication in the past few decades. In 2018, 24,292 HCTs were performed in the AP region, of which 8,754 (36.0%) were autologous and 15,538 (64.0%) were allogeneic. Among the allogeneic HCTs, 10,552 (67.9%) of the recipients were related to their donors, whereas 4,986 (32.1%) were unrelated. In 2019, 27,583 HCTs were reported, of which 17,613 (63.9%) were allogeneic and 9,970 (36.1%) were autologous. Although, in 2010, there was a nearly equal number of related and unrelated HCTs, the difference has shown an annual increase, with more than double (2.05) the number of related than unrelated HCTs in 2019. Recent trends in the AP region show that peripheral blood has overwhelmingly surpassed the bone marrow as a graft source for both related and unrelated HCTs, with the haploidentical donor type being preferred; however, their trends in each country/region were quite different among countries/regions. In 2019, the main conditions requiring HCT were acute myelogenous leukemia (n=6,629 [24.0%]), plasma cell disorders (PCD) (n=4,935 [17.9%]), malignant lymphoma (ML) (n=4,106 [14.9%]), acute lymphoblastic leukemia (AML) (n=3,777 [13.7%]), myelodysplastic syndrome or myelodysplastic/myeloproliferative neoplasm (n=1,913 [6.9%]), severe aplastic anemia (n=1,671 [6.1%]), and hemoglobinopathy (n=910 [3.3%]). PCD and ML were the main indications for autologous HCT, and the number of PCD cases has grown more prominent than the corresponding of ML. The increased number of allogeneic transplants for hemoglobinopathy remains prominent, as well as that of AML and acute lymphocytic leukemia for the past 5 years. There was a significant regional variation in the number of facilities performing HCTs, ranging from one in Mongolia and Nepal to 313 in Japan, and differing regional densities varying from 0.1 in Indonesia and Pakistan to 24.7 in Japan. The total transplant density per 10 million population in each country/region also differed (0.2 in Indonesia and 627 in New Zealand). This annual Activity Survey aims to help all participating countries/regions understand the changes in HCT, serve as an asset in promoting HCT activities in the AP region, and be used as a reference for comparison with other registries from Europe and the United States.
  9. Yap J, Hayashida K, Lee MKY, Stub D, Hon JKF, Ho KW, et al.
    JACC Asia, 2024 Dec;4(12):885-897.
    PMID: 39802986 DOI: 10.1016/j.jacasi.2024.10.001
    Transcatheter aortic valve implantation (TAVI) has been established as an effective treatment modality in patients with severe aortic stenosis (AS) and the uptake of TAVI is rapidly growing in the Asia-Pacific region. However, there exist a heterogeneity in the management of aortic stenosis and the use of TAVI among countries in the region. Reasons for these differences include anatomic variations, disparity in healthcare resources and infrastructure, and the lack of consensus on the optimal management of AS in the Asia-Pacific region. Hence, an Asian Pacific Society of Cardiology (APSC) working group, including a multidisciplinary group of general and interventional cardiologists, cardiac surgeons, imaging specialists, developed a position statement on the recommendations for TAVI in the management of aortic stenosis. The APSC expert panel reviewed and appraised the available evidence using the Grading of Recommendations Assessment, Development, and Evaluation system. Recommendations were developed and put to an online vote. Consensus was reached when 80% of votes for a given recommendation were in support of "agree" or "neutral." The resulting 28 statements provide guidance for clinical practitioners in the region on the use of TAVI in the treatment of patients with aortic stenosis.
  10. Iida M, Ho A, Huang XJ, Liu K, Lv M, Huang H, et al.
    Blood Cell Ther, 2024 Nov 25;7(4):129-137.
    PMID: 39651061 DOI: 10.31547/bct-2024-020
    COVID-19 became a global pandemic in 2020 and significantly affected the activity of hematopoietic cell transplants (HCT) worldwide. Despite these challenges, a total of 28,793 transplants, including 18,518 allogeneic and 10,275 autologous transplants, were performed in 719 facilities in 2020 in the Asia-Pacific (AP) region. This represented a 5.1% increase in allogeneic transplants and a 3.1% increase in autologous transplants, an overall increase of 4.4% compared to the numbers in 2019. With respect to the donor source, haploidentical transplants increased significantly by 18.6%, related transplants by 8.8%, and cord blood transplants (CBT) by 9.2%. However, the number of unrelated transplants, excluding CBT, decreased for the first time by 8.2%. As a result, COVID-19 facilitated the growth of haploidentical transplants due to cross-border restrictions. Regarding the changes in the total number of transplants by country/region in 2020, it increased by 2,048 transplants in China, followed by Japan (210 transplants) and Korea (230 transplants); however, 14 of the 22 countries and regions decreased their number of transplants in 2020 compared to the previous year. There was no correlation between the increase or decrease in the number of transplants in 2020 and the Gross National Income (GNI) per capita of each country/region in 2020, as well as Domestic General Government Health Expenditure as a percentage of General Government Expenditure (GGHE-D/GGE). In 2021, the total number of transplants in this region was 34,754. With the exception of a few countries/regions that decreased the number of transplants in 2020, most countries/regions have started to see a recovery in 2021. The COVID-19 pandemic significantly affected the supply chain and logistics involved in HCT rather than its numbers; however, we have found ways to overcome logistical challenges to carry out transplant medicine without delay, even under these circumstances.
  11. Garderet L, Gras L, Koster L, Baaij L, Hamad N, Dsouza A, et al.
    Am J Hematol, 2024 Nov;99(11):2084-2095.
    PMID: 39158218 DOI: 10.1002/ajh.27451
    Autologous hematopoietic cell transplantation (AHCT) is a commonly used treatment in multiple myeloma (MM). However, real-world global demographic and outcome data are scarce. We collected data on baseline characteristics and outcomes from 61 725 patients with newly diagnosed MM who underwent upfront AHCT between 2013 and 2017 from nine national/international registries. The primary endpoint was overall survival (OS), and the secondary endpoints were progression-free survival (PFS), relapse incidence (RI) and non-relapse mortality (NRM). Median OS amounted to 90.2 months (95% CI 88.2-93.6) and median PFS 36.5 months (95% CI 36.1-37.0). At 24 months, cumulative RI was 33% (95% CI 32.5%-33.4%) and NRM was 2.5% (95% CI 2.3%-2.6%). In the multivariate analysis, superior outcomes were associated with younger age, IgG subtype, complete hematological response at auto-HCT, Karnofsky score of 100%, international staging scoring (ISS) stage 1, HCT-comorbidity index (CI) 0, standard cytogenetic risk, auto-HCT in recent years, and use of lenalidomide maintenance. There were differences in the baseline characteristics and outcomes between registries. While the NRM was 1%-3% at 12 months worldwide, the OS at 36 months was 69%-84%, RI at 12 months was 12%-24% and PFS at 36 months was 43%-63%. The variability in these outcomes is attributable to differences in patient and disease characteristics as well as the use of maintenance and macroeconomic factors. In conclusion, worldwide data indicate that AHCT in MM is a safe and effective therapy with an NRM of 1%-3% with considerable regional differences in OS, PFS, RI, and patient characteristics. Maintenance treatment post-AHCT had a beneficial effect on OS.
  12. Hayrapetyan A, Tumasyan A, Adam W, Andrejkovic JW, Bergauer T, Chatterjee S, et al.
    Phys Rev Lett, 2024 Mar 22;132(12):121901.
    PMID: 38579207 DOI: 10.1103/PhysRevLett.132.121901
    The observation of WWγ production in proton-proton collisions at a center-of-mass energy of 13 TeV with an integrated luminosity of 138  fb^{-1} is presented. The observed (expected) significance is 5.6 (5.1) standard deviations. Events are selected by requiring exactly two leptons (one electron and one muon) of opposite charge, moderate missing transverse momentum, and a photon. The measured fiducial cross section for WWγ is 5.9±0.8(stat)±0.8(syst)±0.7(modeling)  fb, in agreement with the next-to-leading order quantum chromodynamics prediction. The analysis is extended with a search for the associated production of the Higgs boson and a photon, which is generated by a coupling of the Higgs boson to light quarks. The result is used to constrain the Higgs boson couplings to light quarks.
  13. Hayrapetyan A, Tumasyan A, Adam W, Andrejkovic JW, Bergauer T, Chatterjee S, et al.
    Phys Rev Lett, 2024 Jun 14;132(24):241802.
    PMID: 38949350 DOI: 10.1103/PhysRevLett.132.241802
    A search is presented for baryon number violating interactions in top quark production and decay. The analysis uses data from proton-proton collisions at a center-of-mass energy of 13 TeV, collected with the CMS detector at the LHC with an integrated luminosity of 138  fb^{-1}. Candidate events are selected by requiring two oppositely charged leptons (electrons or muons) and exactly one jet identified as originating from a bottom quark. Multivariate discriminants are used to separate the signal from the background. No significant deviation from the standard model prediction is observed. Upper limits are placed on the strength of baryon number violating couplings. For the first time the production of single top quarks via baryon number violating interactions is studied. This allows the search to set the most stringent constraints to date on the branching fraction of the top quark decay to a lepton, an up-type quark (u or c), and a down-type quark (d, s, or b). The results improve the previous bounds by 3 to 6 orders of magnitude based on the fermion flavor combination of the baryon number violating interactions.
  14. Hayrapetyan A, Tumasyan A, Adam W, Andrejkovic JW, Bergauer T, Chatterjee S, et al.
    Phys Rev Lett, 2024 Jan 26;132(4):041802.
    PMID: 38335361 DOI: 10.1103/PhysRevLett.132.041802
    A search for dark matter in events with a displaced nonresonant muon pair and missing transverse momentum is presented. The analysis is performed using an integrated luminosity of 138  fb^{-1} of proton-proton (pp) collision data at a center-of-mass energy of 13 TeV produced by the LHC in 2016-2018. No significant excess over the predicted backgrounds is observed. Upper limits are set on the product of the inelastic dark matter production cross section σ(pp→A^{'}→χ_{1}χ_{2}) and the decay branching fraction B(χ_{2}→χ_{1}μ^{+}μ^{-}), where A^{'} is a dark photon and χ_{1} and χ_{2} are states in the dark sector with near mass degeneracy. This is the first dedicated collider search for inelastic dark matter.
  15. Hayrapetyan A, Tumasyan A, Adam W, Andrejkovic JW, Bergauer T, Chatterjee S, et al.
    Phys Rev Lett, 2024 Feb 09;132(6):061801.
    PMID: 38394587 DOI: 10.1103/PhysRevLett.132.061801
    The first search for scalar leptoquarks produced in τ-lepton-quark collisions is presented. It is based on a set of proton-proton collision data recorded with the CMS detector at the LHC at a center-of-mass energy of 13 TeV corresponding to an integrated luminosity of 138  fb^{-1}. The reconstructed final state consists of a jet, significant missing transverse momentum, and a τ lepton reconstructed through its hadronic or leptonic decays. Limits are set on the product of the leptoquark production cross section and branching fraction and interpreted as exclusions in the plane of the leptoquark mass and the leptoquark-τ-quark coupling strength.
  16. Hayrapetyan A, Tumasyan A, Adam W, Andrejkovic JW, Bergauer T, Chatterjee S, et al.
    Phys Rev Lett, 2024 Mar 15;132(11):111901.
    PMID: 38563916 DOI: 10.1103/PhysRevLett.132.111901
    A search is reported for near-threshold structures in the J/ψJ/ψ invariant mass spectrum produced in proton-proton collisions at sqrt[s]=13  TeV from data collected by the CMS experiment, corresponding to an integrated luminosity of 135  fb^{-1}. Three structures are found, and a model with quantum interference among these structures provides a good description of the data. A new structure is observed with a local significance above 5 standard deviations at a mass of 6638_{-38}^{+43}(stat)_{-31}^{+16}(syst)  MeV. Another structure with even higher significance is found at a mass of 6847_{-28}^{+44}(stat)_{-20}^{+48}(syst)  MeV, which is consistent with the X(6900) resonance reported by the LHCb experiment and confirmed by the ATLAS experiment. Evidence for another new structure, with a local significance of 4.7 standard deviations, is found at a mass of 7134_{-25}^{+48}(stat)_{-15}^{+41}(syst)  MeV. Results are also reported for a model without interference, which does not fit the data as well and shows mass shifts up to 150 MeV relative to the model with interference.
  17. Hayrapetyan A, Tumasyan A, Adam W, Andrejkovic JW, Bergauer T, Chatterjee S, et al.
    Phys Rev Lett, 2024 Jul 05;133(1):011801.
    PMID: 39042800 DOI: 10.1103/PhysRevLett.133.011801
    The first search for singly produced narrow resonances decaying to three well-separated hadronic jets is presented. The search uses proton-proton collision data corresponding to an integrated luminosity of 138  fb^{-1} at sqrt[s]=13  TeV, collected at the CERN LHC. No significant deviations from the background predictions are observed between 1.75 and 9.00 TeV. The results provide the first mass limits on a right-handed boson Z_{R} decaying to three gluons and on an excited quark decaying via a vector boson to three quarks, as well as updated limits on a Kaluza-Klein gluon decaying via a radion to three gluons.
  18. Hayrapetyan A, Tumasyan A, Adam W, Andrejkovic JW, Bergauer T, Chatterjee S, et al.
    Phys Rev Lett, 2024 Nov 08;133(19):191902.
    PMID: 39576923 DOI: 10.1103/PhysRevLett.133.191902
    The first search for soft unclustered energy patterns (SUEPs) is performed using an integrated luminosity of 138  fb^{-1} of proton-proton collision data at sqrt[s]=13  TeV, collected in 2016-2018 by the CMS detector at the LHC. Such SUEPs are predicted by hidden valley models with a new, confining force with a large 't Hooft coupling. In events with boosted topologies, selected by high-threshold hadronic triggers, the multiplicity and sphericity of clustered tracks are used to reject the background from standard model quantum chromodynamics. With no observed excess of events over the standard model expectation, limits are set on the cross section for production via gluon fusion of a scalar mediator with SUEP-like decays.
  19. Hayrapetyan A, Tumasyan A, Adam W, Andrejkovic JW, Bergauer T, Chatterjee S, et al.
    Phys Rev Lett, 2023 Sep 01;131(9):091903.
    PMID: 37721839 DOI: 10.1103/PhysRevLett.131.091903
    A search for the rare η→μ^{+}μ^{-}μ^{+}μ^{-} double-Dalitz decay is performed using a sample of proton-proton collisions, collected by the CMS experiment at the CERN LHC with high-rate muon triggers during 2017 and 2018 and corresponding to an integrated luminosity of 101  fb^{-1}. A signal having a statistical significance well in excess of 5 standard deviations is observed. Using the η→μ^{+}μ^{-} decay as normalization, the branching fraction B(η→μ^{+}μ^{-}μ^{+}μ^{-})=[5.0±0.8(stat)±0.7(syst)±0.7(B_{2μ})]×10^{-9} is measured, where the last term is the uncertainty in the normalization channel branching fraction. This work achieves an improved precision of over 5 orders of magnitude compared to previous results, leading to the first measurement of this branching fraction, which is found to agree with theoretical predictions.
  20. Hayrapetyan A, Tumasyan A, Adam W, Andrejkovic JW, Bergauer T, Chatterjee S, et al.
    Phys Rev Lett, 2024 Aug 16;133(7):071903.
    PMID: 39213583 DOI: 10.1103/PhysRevLett.133.071903
    Energy correlators that describe energy-weighted distances between two or three particles in a hadronic jet are measured using an event sample of sqrt[s]=13  TeV proton-proton collisions collected by the CMS experiment and corresponding to an integrated luminosity of 36.3  fb^{-1}. The measured distributions are consistent with the trends in the simulation that reveal two key features of the strong interaction: confinement and asymptotic freedom. By comparing the ratio of the measured three- and two-particle energy correlator distributions with theoretical calculations that resum collinear emissions at approximate next-to-next-to-leading-logarithmic accuracy matched to a next-to-leading-order calculation, the strong coupling is determined at the Z boson mass: α_{S}(m_{Z})=0.1229_{-0.0050}^{+0.0040}, the most precise α_{S}(m_{Z}) value obtained using jet substructure observables.
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