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  1. 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. Yon H, Shin H, Shin JI, Shin JU, Shin YH, Lee J, et al.
    Rev Med Virol, 2023 Jul;33(4):e2446.
    PMID: 37056203 DOI: 10.1002/rmv.2446
    Little is known about the ongoing monkeypox (mpox) outbreak, and the clinical features of mpox in patients worldwide have not been rigorously analysed. Thus, we aimed to investigate the clinical features associated with mpox infection and understand the pathophysiology and characteristics of the disease. For this systematic review and meta-analysis, we searched PubMed/MEDLINE, Embase, CINAHL, Google Scholar, and the Cochrane Database of Systematic Reviews for articles published till 16 September 2022. We used a random effects model to calculate the pooled prevalence and 95% confidence interval (CI). We used the I2 statistic to assess heterogeneity, Egger's test to assess publication bias, 95% prediction interval to determine the level of uncertainty, and the Newcastle-Ottawa Scale and Joanna Briggs Institute quality assessment tool to assess the risk of bias. Twenty-six relevant articles from 19 countries across 5 continents were included, and data on 5472 mpox patients with 18 unique features were analysed. The pooled prevalence of clinical features of mpox were rash (85.7%, 95% CI: 68.3-94.3; k = 21), chills (77.8%, 95% CI: 70.5-83.7; k = 3), and fever (62.3%, 95% CI: 51.3-71.6; k = 25), lymphadenopathy (58.6%, 95% CI: 47.2-69.2; k = 21), lethargy or exhaustion (46.8%, 95% CI: 30.7-63.5; k = 14), pruritus (40.6%, 95% CI: 28.5-54.0; k = 5), myalgia (36.0%, 95% CI: 24.3-49.7; k = 16), headache (34.6%, 95% CI: 23.4-47.8; k = 17), skin ulcer (31.1%, 95% CI: 18.6-47.1; k = 7), abdomen symptom (24.2%, 95% CI: 17.9-31.9; k = 11), pharyngitis (23.0%, 95% CI: 12.7-37.9; k = 14), respiratory symptom (19.5%, 95% CI: 6.8-44.6; k = 6), nausea or vomiting (13.0%, 95% CI: 4.6-31.9; k = 3), scrotal or penile oedema (10.7%, 95% CI: 6.3-17.7; k = 4), conjunctivitis (7.1%, 95% CI: 2.4-18.9; k = 6), and death (0.9%, 95% CI: 0.4-2.0; k = 26). This is the first international and comprehensive study to examine all clinical presentations of human mpox infection. Our systematic review proposes a comprehensive understanding of the current mpox outbreak and may serve as key data for future studies on the pathological mechanisms and epidemiology of mpox infections.
  3. Yeo KK, Tai BC, Heng D, Lee JM, Ma S, Hughes K, et al.
    Diabetologia, 2006 Dec;49(12):2866-73.
    PMID: 17021918 DOI: 10.1007/s00125-006-0469-z
    AIMS/HYPOTHESIS: The aim of the study was to determine whether the risk of ischaemic heart disease (IHD) associated with diabetes mellitus differs between ethnic groups.

    METHODS: Registry linkage was used to identify IHD events in 5707 Chinese, Malay and Asian Indian participants from three cross-sectional studies conducted in Singapore between the years 1984 and 1995. The study provided a median of 10.2 years of follow-up with 240 IHD events experienced. We assessed the interaction between diabetes mellitus and ethnicity in relation to the risk of IHD events using Cox proportional hazards regression.

    RESULTS: Diabetes mellitus was more common in Asian Indians. Furthermore, diabetes mellitus was associated with a greater risk of IHD in Asian Indians. The hazard ratio when comparing diabetes mellitus with non-diabetes mellitus was 6.41 (95% CI 5.77-7.12) in Asian Indians and 3.07 (95% CI 1.86-5.06) in Chinese (p = 0.009 for interaction). Differences in the levels of established IHD risk factors among diabetics from the three ethnic groups did not appear to explain the differences in IHD risk.

    CONCLUSIONS/INTERPRETATION: Asian Indians are more susceptible to the development of diabetes mellitus than Chinese and Malays. When Asian Indians do develop diabetes mellitus, the risk of IHD is higher than for Chinese and Malays. Consequently, the prevention of diabetes mellitus amongst this ethnic group is particularly important for the prevention of IHD in Asia, especially given the size of the population at risk. Elucidation of the reasons for these ethnic differences may help us understand the pathogenesis of IHD in those with diabetes mellitus.
  4. Yeap SS, Goh EML, Das Gupta E, Lee JK
    APLAR Journal of Rheumatology, 2006;9 Suppl 1:A125-A126.
    DOI: 10.1111/j.1479-8077.2006.00199_20.x
    Aims: The aim of this study was to determine the depth of knowledge about osteoporosis (OP) among the public in Malaysia. Methods: A self-administered questionnaire was distributed to attendees of selected health-related public forums in the Klang Valley and Seremban between the months of May to October 2005. Results: 483 questionnaires were returned from 600 given out (80.5%). There were 139 (28.8%) male, 338 (70%) female respondents and 6 (1.2%) not stated. 87.1% respondents had heard of OP. Significantly more women than men had heard of OP (p = 0.015). Mean age was 50.15 ± 14.6 years, 56.7% in the range of 45-64 years. There was no significant difference in the ages of those who had heard of OP and those who had not. 180/338 (53.3%) were postmenopausal females. Those with >10 years of schooling were more likely to have heard of OP (p RM 1000/month (US$270) were more likely to have heard of OP (p =0.022). 22.6% had a positive family history of OP. 63.1% exercised regularly at an average of 4.26 ± 2.78 hours/week. 4.8% were smokers with a median of 10 cigarettes/day. 24.4% drank alcohol with a median of 1 drink/week. However, 70.9% of respondents said that OP led to falls. 89.6% were concerned about osteoporosis. 90.7% agreed that osteoporosis would make daily activities more difficult. The majority obtained their information about osteoporosis from the printed word; newspapers 55.7%, magazines 46.4%, posters/brochures 30.2%, followed by public talks 30%, relatives 29.6%, television 22.8%, medical clinic 22.6% and internet 11.4%. The majority would ask for more information on osteoporosis from their general practitioner 30.6%, followed by other medical specialists such as orthopaedic surgeons 28.4%, hospital specialists 23.8%, rheumatologists 22.4%, followed by friends 15.9%, relatives 14.3% and pharmacists 11.4%. In this self-selected population, knowledge of OP was better among women, the better educated and those earning a higher level of income. Almost 90% of respondents were concerned about getting OP. Their knowledge of OP was obtained from the printed word, which is an important consideration when considering health promotion activities. General practitioners and orthopaedic surgeons need to have a good knowledge of OP.
  5. Yasin M, Jeong Y, Park S, Jeong J, Lee EY, Lovitt RW, et al.
    Bioresour Technol, 2015 Feb;177:361-74.
    PMID: 25443672 DOI: 10.1016/j.biortech.2014.11.022
    Microbial conversion of syngas to energy-dense biofuels and valuable chemicals is a potential technology for the efficient utilization of fossils (e.g., coal) and renewable resources (e.g., lignocellulosic biomass) in an environmentally friendly manner. However, gas-liquid mass transfer and kinetic limitations are still major constraints that limit the widespread adoption and successful commercialization of the technology. This review paper provides rationales for syngas bioconversion and summarizes the reaction limited conditions along with the possible strategies to overcome these challenges. Mass transfer and economic performances of various reactor configurations are compared, and an ideal case for optimum bioreactor operation is presented. Overall, the challenges with the bioprocessing steps are highlighted, and potential solutions are suggested. Future research directions are provided and a conceptual design for a membrane-based syngas biorefinery is proposed.
  6. Wong JL, Tie ST, Lee J, Kannan SK, Rashid Ali MR, Ibrahim A, et al.
    Med J Malaysia, 2014 Aug;69(4):195-6.
    PMID: 25500852 MyJurnal
    Recurrent respiratory papillomatosis (RRP) is a benign disease caused by the human papilloma virus (HPV), characterized by the formation of recurrent, epithelial neoplastic lesions in the airways. While benign, they can cause significant airway obstruction in some cases. Difficulties in treatment arise from the recurrent nature of the lesions despite repeated procedures. Other known procedures that result in deep tissue damage also cause unacceptable collateral damage to the underlying airway mucosa. We describe a case of recurrent papillomatosis that was successfully treated with argon plasma coagulation ( APC) when laser and electrocautery ablation had failed in the past. After the papillomatasis was treated with APC, there is no recurrence on repeat scope at 4 months and 9 months after the initial procedure. The procedure was done as a day case and there is no complication from the procedure. The property of the APC that allows it to cause only superficial thermal damage to the tissue makes it a suitable adjunct therapy to the treatment of papillomas, which are usually superficial lesions.
  7. Whitton C, Rebello SA, Lee J, Tai ES, van Dam RM
    J Nutr, 2018 Apr 01;148(4):616-623.
    PMID: 29659965 DOI: 10.1093/jn/nxy016
    BACKGROUND: Healthful dietary patterns are associated with cardiovascular disease risk factors in Western populations. However, a consistent healthful dietary pattern across major Asian ethnic groups has yet to be identified.

    OBJECTIVE: We aimed to identify a posteriori dietary patterns for Chinese, Malay, and Indian ethnic groups in an urban Asian setting, compare these with a priori dietary patterns, and ascertain associations with cardiovascular disease risk factors including hypertension, obesity, and abnormal blood lipid concentrations.

    METHODS: We used cross-sectional data from 8433 Singapore residents (aged 21-94 y) from the Multi-Ethnic Cohort study of Chinese, Malay, and Indian ethnicity. Food consumption was assessed using a validated 169-item food-frequency questionnaire. With the use of 28 food groups, dietary patterns were derived by principal component analysis, and their association with cardiovascular disease risk factors was assessed using multiple linear regression. Associations between derived patterns and a priori patterns (aHEI-2010-Alternative Healthy Eating Index-2010, aMED-alternate Mediterranean Diet, and DASH-Dietary Approaches to Stop Hypertension) were assessed, and the magnitude of associations with risk factors compared.

    RESULTS: We identified a "healthy" dietary pattern, similar across ethnic groups, and characterized by high intakes of whole grains, fruit, dairy, vegetables, and unsaturated cooking oil and low intakes of Western fast foods, sugar-sweetened beverages, poultry, processed meat, and flavored rice. This "healthy" pattern was inversely associated with body mass index (BMI; in kg/m2) (-0.26 per 1 SD of the pattern score; 95% CI: -0.36, -0.16), waist circumference (-0.57 cm; 95% CI: -0.82, -0.32), total cholesterol (-0.070 mmol/L; 95% CI: -0.091, -0.048), LDL cholesterol (-0.054 mmol/L; 95% CI: -0.074, -0.035), and fasting triglycerides (-0.22 mmol/L; 95% CI: -0.04, -0.004) and directly associated with HDL cholesterol (0.013 mmol/L; 95% CI: 0.006, 0.021). Generally, "healthy" pattern associations were at least as strong as a priori pattern associations with cardiovascular disease risk factors.

    CONCLUSION: A healthful dietary pattern that correlated well with a priori patterns and was associated with lower BMI, serum LDL cholesterol, total cholesterol, and fasting triglyceride concentrations was identified across 3 major Asian ethnic groups.

  8. Wariki WM, Mori R, Boo NY, Cheah IG, Fujimura M, Lee J, et al.
    J Paediatr Child Health, 2013 Jan;49(1):E23-7.
    PMID: 23282105 DOI: 10.1111/jpc.12054
    The study aims to determine the risk factors associated with mortality and necrotising enterocolitis (NEC) among very low birthweight infants in 95 neonatal intensive care units in the Asian Network on Maternal and Newborn Health.
  9. Wang Q, Liang Z, Li F, Lee J, Low LE, Ling D
    Exploration (Beijing), 2021 Oct;1(2):20210009.
    PMID: 37323214 DOI: 10.1002/EXP.20210009
    Contrast agents can improve the sensitivity and resolution of magnetic resonance imaging (MRI) by accelerating the relaxation times of surrounding water protons. The MRI performances of contrast agents are closely related to their structural characteristics, including size, shape, surface modification, and so on. Recently, dynamically switchable MRI contrast agents that can undergo structural changes and imaging functional activations upon reaching the disease microenvironment have been developed for high performance MRI. This perspective highlights the ingenious design, controllable structural transformation, and tunable imaging property of dynamic MRI contrast agents. Additionally, the current challenges of the dynamic MRI contrast agents for medical diagnosis are discussed. Furthermore, the future integration of high-resolution ultra-high field MRI technology and cutting-edge dynamic MRI contrast agents for non-invasive histopathological level accurate detection of microscopic lesions are commented.
  10. Wan Puteh SE, Manap RA, Hassan TM, Ahmad IS, Idris IB, Sham FM, et al.
    Tob Induc Dis, 2018;16:57.
    PMID: 31516454 DOI: 10.18332/tid/99539
    INTRODUCTION: E-cigarette use is an emerging phenomenon with increasing recognition and acceptance globally. This study aims to create a profile of e-cigarette users among university students in Malaysia.

    METHODS: The study was conducted using a cross-sectional research involving six universities in Malaysia. A semi-structured questionnaire was distributed to 1302 randomly selected students, who either smoked cigarettes and/or e-cigarettes. The 2011 version of Global Adult Tobacco Surveys (GATS) tool was used to record the respondents' sociodemographic data.

    RESULTS: The study revealed that 74.9% of the respondents smoked e-cigarettes; 40.3% used both cigarettes and e-cigarettes (dual users), and 34.5% were exclusive e-cigarette users. The exclusive use of e-cigarettes was related to gender (OR=0.18, 95% CI: 0.09-0.39). Also, male respondents were the majority users (95%). Of the respondents, 75.2 % were Malays, 98.0% single and most believed they have no health problems (92.1%). Further findings revealed the occurrence of adverse effects, dizziness 14.4%, cough 14.1%, and headaches 12.4%. Overall, 57.8% of the respondents used e-cigarettes as a smoking cessation tool, while others consider e-cigarettes a self-image enhancing tool or as part of social activities.

    CONCLUSIONS: Further research on the use of e-cigarettes should be conducted on a large number of respondents in other settings to augment the findings of this study, and also guide policy making on and prevention practice of e-cigarette use, among the general student population in Malaysia.
  11. Wan Mahari WA, Awang S, Zahariman NAZ, Peng W, Man M, Park YK, et al.
    J Hazard Mater, 2022 Feb 05;423(Pt A):127096.
    PMID: 34523477 DOI: 10.1016/j.jhazmat.2021.127096
    Microwave co-pyrolysis was examined as an approach for simultaneous reduction and treatment of environmentally hazardous hospital plastic waste (HPW), lignocellulosic (palm kernel shell, PKS) and triglycerides (waste vegetable oil, WVO) biowaste as co-feedstock. The co-pyrolysis demonstrated faster heating rate (16-43 °C/min) compared to microwave pyrolysis of single feedstock (9-17 °C/min). Microwave co-pyrolysis of HPW/WVO performed at 1:1 ratio produced a higher yield (80.5 wt%) of hydrocarbon liquid fuel compared to HPW/PKS (78.2 wt%). The liquid oil possessed a low nitrogen content (< 4 wt%) and free of sulfur that could reduce the release of hazardous pollutants during its use as fuel in combustion. In particular, the liquid oil obtained from co-pyrolysis of HPW/WVO has low oxygenated compounds (< 16%) leading to reduction in generation of potentially hazardous sludge or problematic acidic tar during oil storage. Insignificant amount of benzene derivatives (< 1%) was also found in the liquid oil, indicating the desirable feature of this pyrolysis approach to suppress the formation of toxic polycyclic aromatic hydrocarbons (PAHs). Microwave co-pyrolysis of HPW/WVO improved the yield and properties of liquid oil for potential use as a cleaner fuel, whereas the liquid oil from co-pyrolysis of HPW/PKS is applicable in the synthesis of phenolic resin.
  12. Wan Hanifah W, Lee J, Quah B
    Malays J Med Sci, 2000 Jan;7(1):33-40.
    PMID: 22844213
    Nosocomial infection is a common problem in the Neonatal Intensive Care Unit (NICU) and a knowledge of the pattern of nosocomial infection will contribute greatly to the intensification of infection control measures and the development of antibiotic policies in the NICU. This study aims to compare the incidence and clinical characteristics of neonates with nosocomial infection in NICU of both Kuala Terengganu Hospital (HKT) and Universiti Sains Malaysia Hospital (HUSM). Neonates who had both clinical signs of sepsis and positive blood cultures, 48 hours after admission to NICU, from 1(st) January to 31(st) December 1998, in both hospitals were retrospectively studied. Among neonates admitted to NICU, 30 (5.4%) in HKT and 65 (3.6%) in HUSM had nosocomial infection (p = 0.07). The mean duration of hospitalisation was shorter (HUSM 37 days, HKT 49 days; p = 0.02), and the number of neonates with predisposing factors for infection is higher (HUSM 100%, HKT 73.3%; p < 0.001) in HUSM compared with HKT. There were no differences in gestation, mean age of onset of infection and mortality between both hospitals. The most common organism isolated from the blood in HKT was Klebsiella pneumoniae (33.3%), and in HUSM Klebsiella aerogenes (24.6%). Half of Klebsiella pneumoniae isolates were resistant to cephalosporins and aminoglycosides in HKT and a similar number of Klebsiella aerogenes isolates were resistant to piperacillin and aminoglycosides in HUSM. In conclusion nosocomial infection is a common problem in both hospitals. Except for more frequent predisposing factors for infection in HUSM, and a longer duration of hospital stay among neonates in HKT, the clinical characteristics of neonates with nosocomial infection in both hospitals were similar.
  13. Wadhwa M, Kang HN, Jivapaisarnpong T, WHO implementation workshop on guidelines on procedures and data requirements for changes to approved biotherapeutic products, Andalucia LR, Blades CDRZ, et al.
    Biologicals, 2020 May;65:50-59.
    PMID: 31959504 DOI: 10.1016/j.biologicals.2019.12.008
    The first global workshop on implementation of the WHO guidelines on procedures and data requirements for changes to approved biotherapeutic products adopted by the WHO Expert Committee in 2018 was held in June 2019. The workshop participants recognized that the principles based on sound science and the potential for risk, as described in the WHO Guidelines on post-approval changes, which constitute the global standard for product life-cycle management are providing clarity and helping national regulatory authorities in establishing guidance while improving time-lines for an efficient regulation of products. Consequently, the regulatory situation for post-approval changes and guideline implementation is changing but there is a disparity between different countries. While the guidelines are gradually being implemented in some countries and also being considered in other countries, the need for regional workshops and further training on post-approval changes was a common theme reiterated by many participants. Given the complexities relating to post-approval changes in different regions/countries, there was a clear understanding among all participants that an efficient approach for product life-cycle management at a national level is needed to ensure faster availability of high standard, safe and efficacious medicines to patients as per the World Health Assembly Resolution 67.21.
  14. Venkataraman K, Kao SL, Thai AC, Salim A, Lee JJ, Heng D, et al.
    Diabet Med, 2012 Jul;29(7):911-7.
    PMID: 22283416 DOI: 10.1111/j.1464-5491.2012.03599.x
    AIMS: To study whether HbA(1c) , and its relationship with fasting plasma glucose, was significantly different among Chinese, Malays and Indians in Singapore.

    METHODS: A sample of 3895 individuals without known diabetes underwent detailed interview and health examination, including anthropometric and biochemical evaluation, between 2004 and 2007. Pearson's correlation, analysis of variance and multiple linear regression analyses were used to examine the influence of ethnicity on HbA(1c) .

    RESULTS: As fasting plasma glucose increased, HbA(1c) increased more in Malays and Indians compared with Chinese after adjustment for age, gender, waist circumference, serum cholesterol, serum triglyceride and homeostasis model assessment of insulin resistance (P-interaction < 0.001). This translates to an HbA(1c) difference of 1.1 mmol/mol (0.1%, Indians vs. Chinese), and 0.9 mmol/mol (0.08%, Malays vs. Chinese) at fasting plasma glucose 5.6 mmol/l (the American Diabetes Association criterion for impaired fasting glycaemia); and 2.1 mmol/mol (0.19%, Indians vs. Chinese) and 2.6 mmol/mol (0.24%, Malays vs. Chinese) at fasting plasma glucose 7.0 mmol/l, the diagnostic criterion for diabetes mellitus.

    CONCLUSIONS: Using HbA(1c) in place of fasting plasma glucose will reclassify different proportions of the population in different ethnic groups. This may have implications in interpretation of HbA(1c) results across ethnic groups and the use of HbA(1c) for diagnosing diabetes mellitus.

  15. Valizadeh S, Ko CH, Lee J, Lee SH, Yu YJ, Show PL, et al.
    J Environ Manage, 2021 Sep 15;294:112959.
    PMID: 34116308 DOI: 10.1016/j.jenvman.2021.112959
    This study highlights the potential of pyrolysis of food waste (FW) with Ni-based catalysts under CO2 atmosphere as an environmentally benign disposal technique. FW was pyrolyzed with homo-type Ni/Al2O3 (Ni-HO) or eggshell-type Ni/Al2O3 (Ni-EG) catalysts under flowing CO2 (50 mL/min) at temperatures from 500 to 700 °C for 1 h. A higher gas yield (42.05 wt%) and a lower condensable yield (36.28 wt%) were achieved for catalytic pyrolysis with Ni-EG than with Ni-HO (34.94 wt% and 40.06 wt%, respectively). In particular, the maximum volumetric content of H2 (21.48%) and CO (28.43%) and the lowest content of C2-C4 (19.22%) were obtained using the Ni-EG. The formation of cyclic species (e.g., benzene derivatives) in bio-oil was also effectively suppressed (24.87%) when the Ni-EG catalyst and CO2 medium were concurrently utilized for the FW pyrolysis. Accordingly, the simultaneous use of the Ni-EG catalyst and CO2 contributed to altering the carbon distribution of the pyrolytic products from condensable species to value-added gaseous products by facilitating ring-opening reactions and free radical mechanisms. This study should suggest that CO2-assisted catalytic pyrolysis over the Ni-EG catalyst would be an eco-friendly and sustainable strategy for disposal of FW which also provides a clean and high-quality source of energy.
  16. 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 .
  17. 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.
  18. 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.
  19. 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.
  20. 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}.
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