Displaying publications 1 - 20 of 242 in total

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  1. Zhu Y, Hu Z, Lv X, Huang R, Gu X, Zhang C, et al.
    Transbound Emerg Dis, 2022 Jul;69(4):1782-1793.
    PMID: 33993639 DOI: 10.1111/tbed.14155
    Since 2010, several duck Tembusu viruses (DTMUVs) have been isolated from infected ducks in China, and these virus strains have undergone extensive variation over the years. Although the infection rate is high, the mortality rate is usually relatively low-~5%-30%; however, since fall 2019, an infectious disease similar to DTMUV infection but with a high mortality rate of ~50% in goslings has been prevalent in Anhui Province, China. The present study identified a new Tembusu virus, designated DTMUV/Goose/China/2019/AQ-19 (AQ-19), that is believed to be responsible for the noticeably high mortality in goslings. To investigate the genetic variation of this strain, its entire genome was sequenced and analysed for specific variations, and goslings and mice were challenged with the isolated virus to investigate its pathogenicity. The AQ-19 genome shared only 94.3%-96.9% and 90.9% nucleotide identity with other Chinese and Malaysian DTMUVs, respectively; however, AQ-19 has high homology with Thailand DTMUVs (97.2%-98.1% nucleotide identity). Phylogenetic analysis of the E gene revealed that AQ-19 and most of Thailand DTMUVs form a branch separate from any of the previously reported DTMUV strains in China. After the challenge, some goslings and mice showed typical clinical signs of DTMUV, particularly severe neurological dysfunction. AQ-19 has high virulence in goslings and mice, resulting in 60% and 70% mortality through intramuscular and intracerebral routes, respectively. Pathological examination revealed severe histological lesions in the brain and liver of the infected goslings and mice. Taken together, these results demonstrated the emergence of a novel Tembusu virus with high virulence circulating in goslings in China for the first time, and our findings highlight the high genetic diversity of DTMUVs in China. Further study of the pathogenicity and host range of this novel Tembusu virus is particularly important.
  2. Wu R, Zou P, Tan G, Hu Z, Wang Y, Ning Z, et al.
    Ecol Evol, 2019 May;9(10):5766-5776.
    PMID: 31160997 DOI: 10.1002/ece3.5160
    Hybridization is very common in flowering plants and it plays a significant role in plant evolution and adaptation. Melastoma L. (Melastomataceae) comprises about 80-90 species in tropical Asia and Oceania, among which 41 species occur in Borneo. Natural hybridization is frequently reported in Melastoma in China, but so far there have been no confirmed cases of hybridization in Southeast Asia (including Borneo), where most species occur. Here, we identified a case of natural hybridization between Melastoma malabathricum L. and Melastoma beccarianum Cogn. in Sarawak, Malaysia, by using sequence data of three nuclear genes and one chloroplast intergenic spacer. Melastoma malabathricum is the most widespread species of this genus, occurring in almost the whole range of this genus, while M. beccarianum is a local species endemic to northern Borneo. Our results showed that natural hybridization and introgression occur between M. malabathricum and M. beccarianum, and the introgression was asymmetrical, mainly from M. malabathricum to M. beccarianum. As adaptive traits can be transferred by introgression, our study suggests that natural hybridization should be a significant mechanism for the evolution and adaptation of Melastoma in Southeast Asia. However, introgression from the common species M. malabathricum to the relatively rare species M. beccarianum may cause the decline of M. beccarianum, incurring conservation concern. With a large number of species of Melastoma and almost year-around flowering in Southeast Asia, more cases of natural hybridization are expected to be found and identified in near future.
  3. Wong LP, Wong PF, Megat Hashim MMAA, Han L, Lin Y, Hu Z, et al.
    Hum Vaccin Immunother, 2020 07 02;16(7):1611-1622.
    PMID: 32429731 DOI: 10.1080/21645515.2020.1756670
    HPV vaccine hesitancy in Asia is unique compared to Western countries due to multidimensional social-cultural norms that influence beliefs regarding vaccination. Reviews on HPV vaccine hesitancy in Asia lack of in-depth discussion regarding the traditional and social-cultural norms dimensions. This paper puts forward opinions in which culture, normative beliefs, and religion influence HPV vaccine hesitancy in Asian countries. Issues surrounding HPV hesitancy among parents, young adult women, adult women, men and the sexual and gender minority people in Asian countries were highlighted. The shortage of HPV vaccine supply would soon be reduced as some Asian countries are on the way to producing the HPV vaccine which production is currently dominated by Western European countries. The culture of favoring imported Western products among many in Asia and in addition to long-existing fake vaccine crisis pose a challenge for the newly emerging HPV vaccine produced in Asia. Some recommendations, research gaps, and future research needs were discussed.
  4. Wong LP, Alias H, Danaee M, Ahmed J, Lachyan A, Cai CZ, et al.
    Infect Dis Poverty, 2021 Oct 07;10(1):122.
    PMID: 34620243 DOI: 10.1186/s40249-021-00900-w
    BACKGROUND: The availability of various types of COVID-19 vaccines and diverse characteristics of the vaccines present a dilemma in vaccination choices, which may result in individuals refusing a particular COVID-19 vaccine offered, hence presenting a threat to immunisation coverage and reaching herd immunity. The study aimed to assess global COVID-19 vaccination intention, vaccine characteristics influencing vaccination acceptance and desirable vaccine characteristics influencing the choice of vaccines.

    METHODS: An anonymous cross-sectional survey was conducted between 4 January and 5 March 2021 in 17 countries worldwide. Proportions and the corresponding 95% confidence intervals (CI) of COVID-19 vaccine acceptance and vaccine characteristics influencing vaccination acceptance were generated and compared across countries and regions. Multivariable logistic regression analysis was used to determine the factors associated with COVID-19 vaccine hesitancy.

    RESULTS: Of the 19,714 responses received, 90.4% (95% CI 81.8-95.3) reported likely or extremely likely to receive COVID-19 vaccine. A high proportion of likely or extremely likely to receive the COVID-19 vaccine was reported in Australia (96.4%), China (95.3%) and Norway (95.3%), while a high proportion reported being unlikely or extremely unlikely to receive the vaccine in Japan (34.6%), the U.S. (29.4%) and Iran (27.9%). Males, those with a lower educational level and those of older age expressed a higher level of COVID-19 vaccine hesitancy. Less than two-thirds (59.7%; 95% CI 58.4-61.0) reported only being willing to accept a vaccine with an effectiveness of more than 90%, and 74.5% (95% CI 73.4-75.5) said they would accept a COVID-19 vaccine with minor adverse reactions. A total of 21.0% (95% CI 20.0-22.0) reported not accepting an mRNA vaccine and 51.8% (95% CI 50.3-53.1) reported that they would only accept a COVID-19 vaccine from a specific country-of-origin. Countries from the Southeast Asia region reported the highest proportion of not accepting mRNA technology. The highest proportion from Europe and the Americas would only accept a vaccine produced by certain countries. The foremost important vaccine characteristic influencing vaccine choice is adverse reactions (40.6%; 95% CI 39.3-41.9) of a vaccine and effectiveness threshold (35.1%; 95% CI 33.9-36.4).

    CONCLUSIONS: The inter-regional and individual country disparities in COVID-19 vaccine hesitancy highlight the importance of designing an efficient plan for the delivery of interventions dynamically tailored to the local population.

  5. Wong LP, Alias H, Danaee M, Lee HY, Tan KM, Tok PSK, et al.
    Front Public Health, 2021;9:787672.
    PMID: 35004587 DOI: 10.3389/fpubh.2021.787672
    Background: The confinement measures during COVID-19 had a massive effect on physical and psychological health in public. This study assessed the impact of containment and coping behaviour among the Malaysia public during the COVID-19 pandemic. Questions assessing the impact of containment and coping behaviours were developed and psychometrically tested. Methods: Exploratory factor analysis (EFA) was conducted with the items using principal component analysis extraction and Varimax rotation. Partial least squares structural equation modelling was used to determine the relationship between coping and impact. Results: The 13-item of impact and 10-item coping instruments were developed with three dimensions identified through EFA. Both scales demonstrated excellent composite reliability and good convergent validity. The survey findings revealed that the impact on individual psychological aspects was prominent, followed by well-being and lifestyle. Mindfulness and physical coping strategies were most commonly reported. Coping through seeking help from health professionals and hotlines had a positive direct effect on well-being and lifestyle (b = 0.231, p < 0.001), psychological (B = 0.132, p < 0.001), and employment-related (0.194, p < 0.001) impacts. Coping through mindfulness practise had a negative effect on well-being and lifestyle-related impact (B = -0.180, p < 0.001) and employment-related impact (B = -0.096, p = 0.008). Conclusions: Despite some limitation, the scales for measuring impact and coping behaviours have the potential to be used as a measurement tool in future studies. Findings highlight the enormous impact of the pandemic on psychological well-being and lifestyles. Health authorities should support individual coping as it was found to be an important resilience-related factor to mitigate the impacts of containment during the pandemic.
  6. Wong LP, Alias H, Tan KM, Wong PF, Murugan DD, Hu Z, et al.
    Front Pharmacol, 2023;14:1254470.
    PMID: 37869747 DOI: 10.3389/fphar.2023.1254470
    Objective: The field of targeting cellular senescence with drug candidates to address age-related comorbidities has witnessed a notable surge of interest and research and development. This study aimed to gather valuable insights from pharmaceutical experts and healthcare practitioners regarding the potential and challenges of translating senolytic drugs for treatment of vascular aging-related disorders. Methods: This study employed a qualitative approach by conducting in-depth interviews with healthcare practitioners and pharmaceutical experts. Participants were selected through purposeful sampling. Thematic analysis was used to identify themes from the interview transcripts. Results: A total of six individuals were interviewed, with three being pharmaceutical experts and the remaining three healthcare practitioners. The significant global burden of cardiovascular diseases presents a potentially large market size that offer an opportunity for the development and marketability of novel senolytic drugs. The pharmaceutical sector demonstrates a positive inclination towards the commercialization of new senolytic drugs targeting vascular aging-related disorders. However potential important concerns have been raised, and these include increasing specificity toward senescent cells to prevent off-site targeting, thus ensuring the safety and efficacy of these drugs. In addition, novel senolytic therapy for vascular aging-related disorders may encounter competition from existing drugs that treat or manage risk factors of cardiovascular diseases. Healthcare practitioners are also in favor of recommending the novel senolytic drugs for vascular aging-related disorders but cautioned that its high cost may hinder its acceptance among patients. Besides sharing the same outcome-related concerns as with the pharmaceutical experts, healthcare practitioners anticipated a lack of awareness among the general public regarding the concept of targeting cellular senescence to delay vascular aging-related disorders, and this knowledge gap extends to healthcare practitioner themselves as well. Conclusion: Senolytic therapy for vascular aging-related disorders holds great promise, provided that crucial concerns surrounding its outcomes and commercial hurdles are effectively addressed.
  7. Wong LP, Farid NDN, Alias H, Yusop SM, Musa Z, Hu Z, et al.
    Front Psychiatry, 2023;14:1165023.
    PMID: 37255690 DOI: 10.3389/fpsyt.2023.1165023
    INTRODUCTION: This study aimed to shed light on how young people from low-income families were responding to COVID-19.

    METHODS: This cross-sectional study recruited young people aged between 18 and 24 years from the low-income-group communities. A convenience sampling approach was used. Google Surveys were used to gather data from the survey. The questionnaire consisted of an assessment of demographic characteristics, lifestyle factors, parent-youth conflict (Parental Environment Questionnaire, PEQ), resilient coping (Brief Resilient Coping Scale, BRCS), and psychological distress (Depression, Anxiety, and Stress Scale-short form, DASS-21).

    RESULTS: A total of 561 complete responses were received. The results showed a low level of parent-child conflict in the overall study population, with a median PEQ of 48.0 [interquartile range (IQR) 36-48]. Higher parent-child conflicts were found in females than in males (OR = 1.75, 95% CI 1.19-2.57) and in youth from households with an income below MYR 2000 than those earning MYR 3,001-5,000 (OR = 4.39, 95% CI 2.40-8.03). A low prevalence of depression (12.5%), anxiety (15.2%), and stress (6.4%) was found. Parent-child conflict remains the strongest significant predictor for higher levels of depression (OR = 10.90, 95% CI 4.31-27.57), anxiety (OR = 11.92, 95% CI 5.05-28.14), and stress (OR = 4.79, 95% CI 1.41-16.33) symptoms. Poor resilient coping was the second strongest predictor for depression and anxiety symptoms. Regarding lifestyle factors, a lower level of physical exercise was associated with higher symptoms of depression. By demographics, females reported more severe symptoms of depression and anxiety than males. Young people from low-income households reported greater severity in symptoms of depression, anxiety, and stress than those from high-income households. Young people who are employed also reported greater severity of anxiety symptoms than those who are unemployed.

    DISCUSSION: The COVID-19 pandemic continues to have an unpredictable impact on the lives of vulnerable youth in low-income families that warrants attention in future advocacy efforts.

  8. Wong LP, Chiu CJ, Alias H, Lee TS, Hu Z, Lin Y
    Front Public Health, 2021;9:710508.
    PMID: 34497793 DOI: 10.3389/fpubh.2021.710508
    Background: The objectives of this study were to investigate risk perceptions and travel intention among the general public in Taiwan during the COVID-19 outbreak. Methods: This study used a cross-sectional online survey to collect data. The questionnaire was disseminated via the social media platform (LINE and Facebook) to the general public. Results: A total of 3,237 complete responses were received, of whom 5.8% (95% CI 5.1-6.7) of the participants reported intent to travel to overseas countries with an apparent community spread and 5.5% (95% CI 4.7-6.3) reported intent to travel to other overseas countries in the next 1 month. A relatively higher proportion (46.5%; 95% CI 44.7-48.2) reported intention for domestic travelling. Participants who viewed travelling to only be risky for older adults or those with medical conditions (OR = 2.19; 95% CI 1.38-3.47) and who perceived that one will not get infected if one takes recommended precautionary measures (OR = 3.12; 95% CI 1.85-5.27) reported higher travelling intention to overseas countries with an apparent community spread. Conclusions: Overall, the findings suggest that risk perceptions were depicted as a strong influence of travel intentions.
  9. Wong LP, Lee HY, Alias H, Zimet G, Liu T, Lin Y, et al.
    Hum Vaccin Immunother, 2024 Dec 31;20(1):2313860.
    PMID: 38359815 DOI: 10.1080/21645515.2024.2313860
    The primary objective of this paper is to serve as a valuable resource for policymakers who are confronted with the evolving landscape of the coronavirus disease 2019 (COVID-19), considering both free and cost-based vaccination approaches. The potential consequences of shifting from free to cost-based vaccination are explored, encompassing its impact on global vaccine equity and prioritization, economic well-being, healthcare systems and delivery, public health policies, and vaccine distribution strategies. Examining past studies on willingness to pay for the initial COVID-19 vaccine dose and booster shots provides insights into how individuals value COVID-19 vaccinations and underscores the significance of addressing issues related to affordability. If COVID-19 vaccinations incur expenses, using effective communication strategies that emphasize the importance of vaccination and personal health benefits can increase willingness to pay. Making COVID-19 vaccines accessible through public health programs or health insurance can help alleviate financial barriers and increase vaccination rates.
  10. Wong LP, Alias H, Farid NDN, Yusop SM, Musa Z, Hu Z, et al.
    Front Public Health, 2023;11:1158698.
    PMID: 37213607 DOI: 10.3389/fpubh.2023.1158698
    INTRODUCTION: This study aims to shed light on parent-child relationships and the psychological health of parents from low-income families after the easing of the COVID-19 pandemic restrictions.

    METHODS: This cross-sectional study recruited 553 parents of children aged 13-24 years in low-income community settings. The Parent-Child Conflict scale of the Parental Environment Questionnaire (PEQ) was used to measure parent-child conflict. Psychological distress was assessed using the Depression, Anxiety, and Stress Scale short form (DASS-21).

    RESULTS: The study revealed a low level of parent-child conflict in the overall study population, with a median PEQ of 48.0 (interquartile range [IQR] 36 to 48). Concerning demographics, married parents reported a likelihood of having a higher level of parent-child conflict over 3 times higher than single parents (OR = 3.18 95%, CI 1.30-7.75). More parent-child conflicts were also found in parents aged 60-72 years old who were unemployed, retired, or housewives and from lower-income groups. In regard to lifestyle factors, a higher level of physical activity and having enough sleep were associated with lower levels of parent-child conflict. Only approximately 1% of the participants reported symptoms of depression, anxiety, or stress.

    DISCUSSION: Low risk exists for parent-child conflict and psychological sequelae following the easing of the COVID-19 pandemic restrictions, which could be due to various support measures implemented by the government. Vulnerable parents identified as being at risk of parent-child conflict warrant attention in future advocacy efforts.

  11. Wong LP, Alias H, Lee HY, AbuBakar S, Lin Y, Hu Z
    BMC Womens Health, 2024 Mar 21;24(1):190.
    PMID: 38515067 DOI: 10.1186/s12905-024-02999-z
    BACKGROUND: Although Zika virus infection is rarely reported now, continuous prevention is needed to achieve sustained eradication. This study aimed to explore the knowledge gaps, risk perception and preventive measures against Zika virus infection (ZIKV) in pregnant women in Malaysia.

    METHODS: We conducted in-depth virtual interviews with pregnant women between February and April 2022. The interviews were recorded and transcribed, and data were analyzed by content analysis.

    RESULTS: The majority of the participants demonstrated a commendable level of awareness regarding the signs and symptoms associated with ZIKV infection. They also exhibited a clear understanding of preventive measures, particularly emphasizing the importance of avoiding mosquito bites to minimize the risk of ZIKV transmission. However, a noteworthy gap in knowledge surfaced as a subset of participants remained uninformed about the potential for sexual transmission of ZIKV, which could lead to congenital ZIKV in pregnant women. Even among women who were cognizant of ZIKV and its potential negative health outcomes, associated with the infection, many of them did not perceive themselves to be at risk, mainly because ZIKV infection is infrequently discussed or heard of, leading to a sense of infections' rarity. While the adoption of preventive measures such as mosquito bite prevention during pregnancy was a common practice, however, prevention of sexually transmitted infections (STIs) including mosquito-borne diseases such as Zika is low. A minority of women express concerns about the sensitivity surrounding discussions and prevention of STIs within the context of marriage. Most of the participants were supportive of the provision of awareness of ZIKV infection in women during pregnancy and the involvement of men, especially in initiatives aimed at preventing transmission through sexual contact.

    CONCLUSION: This study uncovered gaps in both knowledge and practices pertaining ZIKV infection among pregnant women in the aftermath of the ZIKV pandemic. The insights gleaned from our research are valuable for shaping future interventions geared towards preventing the resurgence or facilitating the sustainable eradication of ZIKV.

  12. Wong LP, Lin Y, Alias H, Bakar SA, Zhao Q, Hu Z
    Healthcare (Basel), 2021 Nov 09;9(11).
    PMID: 34828576 DOI: 10.3390/healthcare9111530
    PURPOSE: This study analyzed the insights and sentiments of COVID-19 anti-vaccine comments from Instagram feeds and Facebook postings. The sentiments related to the acceptance and effectiveness of the vaccines that were on the verge of being made available to the public.

    PATIENTS AND METHODS: The qualitative software QSR-NVivo 10 was used to manage, code, and analyse the data.

    RESULTS: The analyses uncovered several major issues concerning COVID-19 vaccine hesitancy. The production of the COVID-19 vaccine at an unprecedented speed evoked the fear of skipping steps that would compromise vaccine safety. The unknown long-term effects and duration of protection erode confidence in taking the vaccines. There were also persistent concerns with regard to vaccine compositions that could be harmful or contain aborted foetal cells. The rate of COVID-19 death was viewed as low. Many interpreted the 95% effectiveness of the COVID-19 vaccine as insufficient. Preference for immunity gains from having an infection was viewed as more effective. Peer-reviewed publication-based data were favoured as a source of trust in vaccination decision-making.

    CONCLUSIONS: The anti-COVID-19 vaccine sentiments found in this study provide important insights for the formulation of public health messages to instill confidence in the vaccines.

  13. Wang H, Liu K, He Z, Chen Y, Hu Z, Chen W, et al.
    Mar Pollut Bull, 2024 Apr;201:116198.
    PMID: 38428045 DOI: 10.1016/j.marpolbul.2024.116198
    Metabarcoding analysis is an effective technique for monitoring the domoic acid-producing Pseudo-nitzschia species in marine environments, uncovering high-levels of molecular diversity. However, such efforts may result in the overinterpretation of Pseudo-nitzschia species diversity, as molecular diversity not only encompasses interspecies and intraspecies diversities but also exhibits extensive intragenomic variations (IGVs). In this study, we analyzed the V4 region of the 18S rDNA of 30 strains of Pseudo-nitzschia multistriata collected from the coasts of China. The results showed that each P. multistriata strain harbored about a hundred of unique 18S rDNA V4 sequence varieties, of which each represented by a unique amplicon sequence variant (ASV). This study demonstrated the extensive degree of IGVs in P. multistriata strains, suggesting that IGVs may also present in other Pseudo-nitzschia species and other phytoplankton species. Understanding the scope and levels of IGVs is crucial for accurately interpreting the results of metabarcoding analysis.
  14. 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 .
  15. 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.
  16. 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.
  17. 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.
  18. 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}.
  19. 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.
  20. 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
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