Displaying publications 1 - 20 of 315 in total

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  1. Yue L, Xue D, Draz MU, Ahmad F, Li J, Shahzad F, et al.
    PMID: 31936543 DOI: 10.3390/ijerph17020446
    Urbanization has made tremendous contributions to China's economic development since its economic reforms and opening up. At the same time, population agglomeration has aggravated environmental pollution and posed serious challenges to China's environment. This article empirically investigates the impacts of China's urbanization on eco-efficiency, comprehensively reflecting economic growth, resource input, and waste discharge. We first measured the provincial eco-efficiency in China from 2005 to 2015 using the Super Slack-Based model (Super-SBM). We then constructed a spatial model to empirically analyze the effects of urbanization on eco-efficiency at the national level, and at four regional levels. The results indicated that the regional eco-efficiency in China has fluctuated, but is generally improving, and that a gap between regions was evident, with a trend toward further gap expansion. We observed an effect of spatial spillover in eco-efficiency, which was significant and positive for the whole country, except for the western region. The influence of urbanization on China's eco-efficiency exhibited a U-curve relationship. The changing trend in the eastern, central, and western regions was the same as that in the whole country; however, the trend exhibited an inverted U-curve relationship in the northeastern region. To the best of our knowledge, covering a time period of 2005-2015, this article is the first of its kind to study the impact of urbanization on eco-efficiency in China at both the national and regional levels. This study may help policy-makers to create sustainable policies that could be helpful in balancing urbanization and the ecological environment.
  2. Zelenev A, Li J, Mazhnaya A, Basu S, Altice FL
    Lancet Infect Dis, 2018 02;18(2):215-224.
    PMID: 29153265 DOI: 10.1016/S1473-3099(17)30676-X
    BACKGROUND: Chronic infections with hepatitis C virus (HCV) and HIV are highly prevalent in the USA and concentrated in people who inject drugs. Treatment as prevention with highly effective new direct-acting antivirals is a prospective HCV elimination strategy. We used network-based modelling to analyse the effect of this strategy in HCV-infected people who inject drugs in a US city.

    METHODS: Five graph models were fit using data from 1574 people who inject drugs in Hartford, CT, USA. We used a degree-corrected stochastic block model, based on goodness-of-fit, to model networks of injection drug users. We simulated transmission of HCV and HIV through this network with varying levels of HCV treatment coverage (0%, 3%, 6%, 12%, or 24%) and varying baseline HCV prevalence in people who inject drugs (30%, 60%, 75%, or 85%). We compared the effectiveness of seven treatment-as-prevention strategies on reducing HCV prevalence over 10 years and 20 years versus no treatment. The strategies consisted of treatment assigned to either a randomly chosen individual who injects drugs or to an individual with the highest number of injection partners. Additional strategies explored the effects of treating either none, half, or all of the injection partners of the selected individual, as well as a strategy based on respondent-driven recruitment into treatment.

    FINDINGS: Our model estimates show that at the highest baseline HCV prevalence in people who inject drugs (85%), expansion of treatment coverage does not substantially reduce HCV prevalence for any treatment-as-prevention strategy. However, when baseline HCV prevalence is 60% or lower, treating more than 120 (12%) individuals per 1000 people who inject drugs per year would probably eliminate HCV within 10 years. On average, assigning treatment randomly to individuals who inject drugs is better than targeting individuals with the most injection partners. Treatment-as-prevention strategies that treat additional network members are among the best performing strategies and can enhance less effective strategies that target the degree (ie, the highest number of injection partners) within the network.

    INTERPRETATION: Successful HCV treatment as prevention should incorporate the baseline HCV prevalence and will achieve the greatest benefit when coverage is sufficiently expanded.

    FUNDING: National Institute on Drug Abuse.

  3. Zelenev A, Michael L, Li J, Altice FL
    Int J Drug Policy, 2024 Jan;123:104250.
    PMID: 38088004 DOI: 10.1016/j.drugpo.2023.104250
    BACKGROUND: Opioid agonist therapies (OAT) and  harm reduction such as syringe service programs (SSP) have been shown to be effective in preventing adverse outcomes such as overdose deaths, HIV and Hepatitis C infections among people who inject drugs (PWID). The importance of social network influence on disease transmission is well established, yet the interplay between harm reduction and network structures is, generally, not well understood. This study aims to analyze how social networks can mediate the harm reduction effects associated with secondary exchange through syringe service programs (SSP) and opioid agonist therapies (OAT) among injection network members.

    METHODS: Sociometric data on networks on people who inject drugs from Hartford, CT, which were collected in 2012-2013, provided assessment of risk behaviors among 1574 injection network members, including participation in OAT and SSP. Subject's network characteristics were examined in relation to retention in OAT, as well as secondary syringe exchange using exponential random graph model (ERGM) and regression.

    RESULTS: Based on the analysis, we found that probability of individuals being retained in OAT was positively associated with the OAT retention status of their peers within the network. Using simulations, we found that higher levels of positive correlation of OAT retention among network members can result in reduced risk of transmission of HIV to network partners on OAT. In addition, we found that secondary syringe exchange engagement was associated with higher probability of sharing of paraphernalia and unsterile needles at the network level.

    CONCLUSIONS: Understanding how networks mediate risk behaviors is crucial for making progress toward ending the HIV epidemic.

  4. Zelenev A, Li J, Shea P, Hecht R, Altice FL
    Clin Infect Dis, 2021 Mar 01;72(5):755-763.
    PMID: 32060534 DOI: 10.1093/cid/ciaa142
    BACKGROUND: Hepatitis C virus (HCV) treatment as prevention (TasP) strategies can contribute to HCV microelimination, yet complimentary interventions such as opioid agonist therapies (OAT) with methadone or buprenorphine and syringe services programs (SSPs) may improve the prevention impact. This modeling study estimates the impact of scaling up the combination of OAT and SSPs with HCV TasP in a network of people who inject drugs (PWID) in the United States.

    METHODS: Using empirical data from Hartford, Connecticut, we deployed a stochastic block model to simulate an injection network of 1574 PWID. We used a susceptible-infected model for HCV and human immunodeficiency virus to evaluate the effectiveness of several HCV TasP strategies, including in combination with OAT and SSP scale-up, over 20 years.

    RESULTS: At the highest HCV prevalence (75%), when OAT coverage is increased from 10% to 40%, combined with HCV treatment of 10% per year and SSP scale up to 40%, the time to achieve microelimination is reduced from 18.4 to 11.6 years. At the current HCV prevalence (60%), HCV TasP strategies as low as 10% coverage per year may achieve HCV microelimination within 10 years, with minimal impact from additional OAT scale-up. Strategies based on mass initial HCV treatment (50 per 100 PWID the first year followed by 5 per 100 PWID thereafter) were most effective in settings with HCV prevalence of 60% or lower.

    CONCLUSIONS: Scale-up of HCV TasP is the most effective strategy for microelimination of HCV. OAT scale-up, however, scale-up may be synergistic toward achieving microelimination goals when HCV prevalence exceeds 60% and when HCV treatment coverage is 10 per 100 PWID per year or lower.

  5. Ong SK, Haruyama R, Yip CH, Ngan TT, Li J, Lai D, et al.
    EClinicalMedicine, 2024 Jan;67:102365.
    PMID: 38125964 DOI: 10.1016/j.eclinm.2023.102365
    BACKGROUND: The Global Breast Cancer Initiative (GBCI) Framework, launched by the World Health Organisation (WHO) in 2023, emphasises assessing, strengthening, and scaling up services for the early detection and management of breast cancer. This study aims to determine the feasibility of monitoring the status of breast cancer control in the 21 Asian National Cancer Centers Alliance (ANCCA) countries based on the three GBCI Framework key performance indicators (KPIs): stage at diagnosis, time to diagnosis, and treatment completion.

    METHODS: We reviewed published literature on breast cancer control among 21 ANCCA countries from May to July 2023 to establish data availability and compiled the latest descriptive statistics and sources of the indicators using a standardised data collection form. We performed bivariate Pearson's correlation analysis to measure the strength of correlation between stage at diagnosis, mortality and survival rates, and universal health coverage.

    FINDINGS: Only 12 (57%) ANCCA member countries published national cancer registry reports on breast cancer age-standardised incidence rate (ASIR) and age-standardised mortality rate (ASMR). Indonesia, Myanmar, and Nepal had provincial data and others relied on WHO's Global Cancer Observatory (GLOBOCAN) estimates. GLOBOCAN data differed from the reported national statistics by 5-10% in Bhutan, Indonesia, Iran, the Republic of Korea, Singapore, and Thailand and >10% in China, India, Malaysia, Mongolia, and Sri Lanka. The proportion of patients diagnosed in stages I and II strongly correlated with the five-year survival rate and with the universal health coverage (UHC) index. Three countries (14%) reported national data with >60% of invasive breast cancer patients diagnosed at stages I and II, and a five-year survival rate of >80%. Over 60% of the ANCCA countries had no published national data on breast cancer staging, the time interval from presentation to diagnosis, and diagnosis to treatment. Five (24%) countries reported data on treatment completion. The definition of delayed diagnosis and treatment completion varied across countries.

    INTERPRETATION: GBCI's Pillar 1 KPI correlates strongly with five-year survival rate and with the UHC index. Most ANCCA countries lacked national data on cancer staging, timely diagnosis, and treatment completion KPIs. While institutional-level data were available in some countries, they may not represent the nationwide status. Strengthening cancer surveillance is crucial for effective breast cancer control. The GBCI Framework indicators warrant more detailed definitions for standardised data collection. Surrogate indicators which are measurable and manageable in country-specific settings, could be considered for monitoring GBCI indicators. Ensuring UHC and addressing health inequalities are essential to early diagnosis and treatment of breast cancer.

    FUNDING: Funding for this research article's processing fee (APC) will be provided by the affiliated institution to support the open-access publication of this work. The funding body is not involved in the study design; collection, management, analysis and interpretation of data; or the decision to submit for publication. The funding body will be informed of any planned publications, and documentation provided.

  6. Ho WK, Tan MM, Mavaddat N, Tai MC, Mariapun S, Li J, et al.
    Nat Commun, 2020 07 31;11(1):3833.
    PMID: 32737321 DOI: 10.1038/s41467-020-17680-w
    Polygenic risk scores (PRS) have been shown to predict breast cancer risk in European women, but their utility in Asian women is unclear. Here we evaluate the best performing PRSs for European-ancestry women using data from 17,262 breast cancer cases and 17,695 controls of Asian ancestry from 13 case-control studies, and 10,255 Chinese women from a prospective cohort (413 incident breast cancers). Compared to women in the middle quintile of the risk distribution, women in the highest 1% of PRS distribution have a ~2.7-fold risk and women in the lowest 1% of PRS distribution has ~0.4-fold risk of developing breast cancer. There is no evidence of heterogeneity in PRS performance in Chinese, Malay and Indian women. A PRS developed for European-ancestry women is also predictive of breast cancer risk in Asian women and can help in developing risk-stratified screening programmes in Asia.
  7. Cheah PL, Li J, Looi LM, Teoh KH, Ong DB, Arends MJ
    PeerJ, 2018;6:e5530.
    PMID: 30221090 DOI: 10.7717/peerj.5530
    Background: Except for a few studies with contradictory observations, information is lacking on the possibility of association between DNA mismatch repair (MMR) status and the presence of cancer stem cells in colorectal carcinoma (CRC), two important aspects in colorectal carcinogenesis.

    Methods: Eighty (40 right-sided and 40 left-sided) formalin-fixed, paraffin-embedded primary CRC were immunohistochemically studied for CD133, a putative CRC stem cell marker, and MMR proteins MLH1, MSH2, MSH6 and PMS2. CD133 expression was semi-quantitated for proportion of tumor immunopositivity on a scale of 0-5 and staining intensity on a scale of 0-3 with a final score (units) being the product of proportion and intensity of tumor staining. The tumor was considered immunopositive only when the tumor demonstrated moderate to strong intensity of CD133 staining (a decision made after analysis of CD133 expression in normal colon). Deficient MMR (dMMR) was interpreted as unequivocal loss of tumor nuclear staining for any MMR protein despite immunoreactivity in the internal positive controls.

    Results: CD133 was expressed in 36 (90.0%) left-sided and 28 (70.0%) right-sided tumors (p  0.05).

    Conclusion: Proficient MMR correlated with high levels of CD133-marked putative cancer stem cells in both right- and left-sided tumors, whereas significantly lower levels of CD133-marked putative cancer stem cells were associated with deficient MMR status in colorectal carcinomas found on the right.

  8. Lee JK, Mitchell PJ, Ang SB, Mercado-Asis LB, Rey-Matias R, Li J, et al.
    Arch Osteoporos, 2024 Apr 02;19(1):24.
    PMID: 38565791 DOI: 10.1007/s11657-024-01375-6
    A survey of awareness and attitudes to the management of fragility fractures among the membership of the Asia Pacific Orthopaedic Association conducted in 2022 found considerable variation in care across the region. A Call to Action is proposed to improve acute care, rehabilitation and secondary fracture prevention across Asia Pacific.

    PURPOSE: Fragility fractures impose a substantial burden on older people and their families, healthcare systems and national economies. The current incidence of hip and other fragility fractures across the Asia Pacific region is enormous and set to escalate rapidly in the coming decades. This publication describes findings of a survey of awareness and attitudes to the management of fragility fractures among the membership of the Asia Pacific Orthopaedic Association (APOA) conducted in 2022.

    METHODS: The survey was developed as a collaboration between the Asia Pacific Osteoporosis and Fragility Fracture Society and the Asia Pacific Fragility Fracture Alliance, and included questions relating to aspects of care upon presentation, during surgery and mobilisation, secondary fracture prevention, and access to specific services.

    RESULTS: In total, 521 APOA members completed the survey and marked variation in delivery of care was evident. Notable findings included: Fifty-nine percent of respondents indicated that analgesia was routinely initiated in transit (by paramedics) or within 30 minutes of arrival in the Emergency Department. One-quarter of respondents stated that more than 80% of their patients underwent surgery within 48 hours of admission. One-third of respondents considered non-hip, non-vertebral fractures to merit assessment of future fracture risk. One-third of respondents reported the presence of an Orthogeriatric Service in their hospital, and less than a quarter reported the presence of a Fracture Liaison Service.

    CONCLUSION: A Call to Action for all National Orthopaedic Associations affiliated with APOA is proposed to improve the care of fragility fracture patients across the region.

  9. Ng SC, Tang W, Leong RW, Chen M, Ko Y, Studd C, et al.
    Gut, 2015 Jul;64(7):1063-71.
    PMID: 25217388 DOI: 10.1136/gutjnl-2014-307410
    The rising incidence of inflammatory bowel disease in Asia supports the importance of environmental risk factors in disease aetiology. This prospective population-based case-control study in Asia-Pacific examined risk factors prior to patients developing IBD.
  10. Chiu HM, Ching JY, Wu KC, Rerknimitr R, Li J, Wu DC, et al.
    Gastroenterology, 2016 Mar;150(3):617-625.e3.
    PMID: 26627608 DOI: 10.1053/j.gastro.2015.11.042
    BACKGROUND & AIMS: Age, sex, smoking, and family history are risk factors for colorectal cancer in Asia. The Asia-Pacific Colorectal Screening (APCS) scoring system was developed to identify subjects with a high risk for advanced neoplasm (AN). We tested an algorithm that combined APCS scores with fecal immunochemical test (FIT) in colorectal cancer screening.
    METHODS: We performed a multicenter prospective study, enrolling asymptomatic individuals older than 40 years old in 12 Asia-Pacific regions from December 2011 to December 2013. APCS scores were calculated for each individual (0-1 = low risk [LR], 2-3 = medium risk [MR], and 4-7 = high risk [HR] for AN). LR and MR subjects were offered FIT and referred for early colonoscopies if FIT results were positive. HR subjects were offered colonoscopies. The proportions of subjects with ANs were determined for each group based on colonoscopy findings; odd ratios for LR and MR subjects were calculated compared to LR individuals. We calculated the sensitivity of the APCS-FIT algorithm in identifying subjects with AN.
    RESULTS: A total of 5657 subjects were recruited: 646 subjects (11.4%) were considered LR, 3243 subjects (57.3%) were considered MR, and 1768 subjects (31.3%) were considered HR for AN. The proportions of individuals with an AN in these groups were 1.5%, 5.1%, and 10.9%, respectively. Compared with LR group, MR and HR subjects had a 3.4-fold increase and a 7.8-fold increase in risk for AN, respectively. A total of 70.6% subjects with AN (95% confidence interval: 65.6%-75.1%) and 95.1% subjects with invasive cancers (95% confidence interval: 82.2%-99.2%) were correctly instructed to undergo early colonoscopy examination.
    CONCLUSIONS: The APCS scoring system, which is based on age, sex, family history, and smoking, is a useful tool for determining risk for colorectal cancer and advanced adenoma in asymptomatic subjects. Use of the APCS score-based algorithm in triaging subjects for FIT or colonoscopy can substantially reduce colonoscopy workload.
  11. Ghoussaini M, Edwards SL, Michailidou K, Nord S, Cowper-Sal Lari R, Desai K, et al.
    Nat Commun, 2014 Sep 23;4:4999.
    PMID: 25248036 DOI: 10.1038/ncomms5999
    GWAS have identified a breast cancer susceptibility locus on 2q35. Here we report the fine mapping of this locus using data from 101,943 subjects from 50 case-control studies. We genotype 276 SNPs using the 'iCOGS' genotyping array and impute genotypes for a further 1,284 using 1000 Genomes Project data. All but two, strongly correlated SNPs (rs4442975 G/T and rs6721996 G/A) are excluded as candidate causal variants at odds against >100:1. The best functional candidate, rs4442975, is associated with oestrogen receptor positive (ER+) disease with an odds ratio (OR) in Europeans of 0.85 (95% confidence interval=0.84-0.87; P=1.7 × 10(-43)) per t-allele. This SNP flanks a transcriptional enhancer that physically interacts with the promoter of IGFBP5 (encoding insulin-like growth factor-binding protein 5) and displays allele-specific gene expression, FOXA1 binding and chromatin looping. Evidence suggests that the g-allele confers increased breast cancer susceptibility through relative downregulation of IGFBP5, a gene with known roles in breast cell biology.
  12. Orr N, Dudbridge F, Dryden N, Maguire S, Novo D, Perrakis E, et al.
    Hum Mol Genet, 2015 May 15;24(10):2966-84.
    PMID: 25652398 DOI: 10.1093/hmg/ddv035
    We recently identified a novel susceptibility variant, rs865686, for estrogen-receptor positive breast cancer at 9q31.2. Here, we report a fine-mapping analysis of the 9q31.2 susceptibility locus using 43 160 cases and 42 600 controls of European ancestry ascertained from 52 studies and a further 5795 cases and 6624 controls of Asian ancestry from nine studies. Single nucleotide polymorphism (SNP) rs676256 was most strongly associated with risk in Europeans (odds ratios [OR] = 0.90 [0.88-0.92]; P-value = 1.58 × 10(-25)). This SNP is one of a cluster of highly correlated variants, including rs865686, that spans ∼14.5 kb. We identified two additional independent association signals demarcated by SNPs rs10816625 (OR = 1.12 [1.08-1.17]; P-value = 7.89 × 10(-09)) and rs13294895 (OR = 1.09 [1.06-1.12]; P-value = 2.97 × 10(-11)). SNP rs10816625, but not rs13294895, was also associated with risk of breast cancer in Asian individuals (OR = 1.12 [1.06-1.18]; P-value = 2.77 × 10(-05)). Functional genomic annotation using data derived from breast cancer cell-line models indicates that these SNPs localise to putative enhancer elements that bind known drivers of hormone-dependent breast cancer, including ER-α, FOXA1 and GATA-3. In vitro analyses indicate that rs10816625 and rs13294895 have allele-specific effects on enhancer activity and suggest chromatin interactions with the KLF4 gene locus. These results demonstrate the power of dense genotyping in large studies to identify independent susceptibility variants. Analysis of associations using subjects with different ancestry, combined with bioinformatic and genomic characterisation, can provide strong evidence for the likely causative alleles and their functional basis.
  13. Cale EM, Gorman J, Radakovich NA, Crooks ET, Osawa K, Tong T, et al.
    Immunity, 2017 05 16;46(5):777-791.e10.
    PMID: 28514685 DOI: 10.1016/j.immuni.2017.04.011
    Most HIV-1-specific neutralizing antibodies isolated to date exhibit unusual characteristics that complicate their elicitation. Neutralizing antibodies that target the V1V2 apex of the HIV-1 envelope (Env) trimer feature unusually long protruding loops, which enable them to penetrate the HIV-1 glycan shield. As antibodies with loops of requisite length are created through uncommon recombination events, an alternative mode of apex binding has been sought. Here, we isolated a lineage of Env apex-directed neutralizing antibodies, N90-VRC38.01-11, by using virus-like particles and conformationally stabilized Env trimers as B cell probes. A crystal structure of N90-VRC38.01 with a scaffolded V1V2 revealed a binding mode involving side-chain-to-side-chain interactions that reduced the distance the antibody loop must traverse the glycan shield, thereby facilitating V1V2 binding via a non-protruding loop. The N90-VRC38 lineage thus identifies a solution for V1V2-apex binding that provides a more conventional B cell pathway for vaccine design.
  14. Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Asilar E, Bergauer T, et al.
    Phys Rev Lett, 2020 Sep 04;125(10):102001.
    PMID: 32955327 DOI: 10.1103/PhysRevLett.125.102001
    The first study of charm quark diffusion with respect to the jet axis in heavy ion collisions is presented. The measurement is performed using jets with p_{T}^{jet}>60  GeV/c and D^{0} mesons with p_{T}^{D}>4  GeV/c in lead-lead (Pb-Pb) and proton-proton (pp) collisions at a nucleon-nucleon center-of-mass energy of sqrt[s_{NN}]=5.02  TeV, recorded by the CMS detector at the LHC. The radial distribution of D^{0} mesons with respect to the jet axis is sensitive to the production mechanisms of the meson, as well as to the energy loss and diffusion processes undergone by its parent parton inside the strongly interacting medium produced in Pb-Pb collisions. When compared to Monte Carlo event generators, the radial distribution in pp collisions is found to be well described by pythia, while the slope of the distribution predicted by sherpa is steeper than that of the data. In Pb-Pb collisions, compared to the pp results, the D^{0} meson distribution for 4
  15. Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Bergauer T, Dragicevic M, et al.
    Phys Rev Lett, 2020 Oct 09;125(15):152001.
    PMID: 33095627 DOI: 10.1103/PhysRevLett.125.152001
    Using a data sample of proton-proton collisions at sqrt[s]=13  TeV, corresponding to an integrated luminosity of 140  fb^{-1} collected by the CMS experiment in 2016-2018, the B_{s}^{0}→X(3872)ϕ decay is observed. Decays into J/ψπ^{+}π^{-} and K^{+}K^{-} are used to reconstruct, respectively, the X(3872) and ϕ. The ratio of the product of branching fractions B[B_{s}^{0}→X(3872)ϕ]B[X(3872)→J/ψπ^{+}π^{-}] to the product B[B_{s}^{0}→ψ(2S)ϕ]B[ψ(2S)→J/ψπ^{+}π^{-}] is measured to be [2.21±0.29(stat)±0.17(syst)]%. The ratio B[B_{s}^{0}→X(3872)ϕ]/B[B^{0}→X(3872)K^{0}] is found to be consistent with one, while the ratio B[B_{s}^{0}→X(3872)ϕ]/B[B^{+}→X(3872)K^{+}] is two times smaller. This suggests a difference in the production dynamics of the X(3872) in B^{0} and B_{s}^{0} meson decays compared to B^{+}. The reported observation may shed new light on the nature of the X(3872) particle.
  16. Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Asilar E, Bergauer T, et al.
    Phys Rev Lett, 2018 May 18;120(20):202005.
    PMID: 29864318 DOI: 10.1103/PhysRevLett.120.202005
    A search for resonancelike structures in the B_{s}^{0}π^{±} invariant mass spectrum is performed using proton-proton collision data collected by the CMS experiment at the LHC at sqrt[s]=8  TeV, corresponding to an integrated luminosity of 19.7  fb^{-1}. The B_{s}^{0} mesons are reconstructed in the decay chain B_{s}^{0}→J/ψϕ, with J/ψ→μ^{+}μ^{-} and ϕ→K^{+}K^{-}. The B_{s}^{0}π^{±} invariant mass distribution shows no statistically significant peaks for different selection requirements on the reconstructed B_{s}^{0} and π^{±} candidates. Upper limits are set on the relative production rates of the X(5568) and B_{s}^{0} states times the branching fraction of the decay X(5568)^{±}→B_{s}^{0}π^{±}. In addition, upper limits are obtained as a function of the mass and the natural width of possible exotic states decaying into B_{s}^{0}π^{±}.
  17. Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Asilar E, Bergauer T, et al.
    Phys Rev Lett, 2018 May 18;120(20):201801.
    PMID: 29864370 DOI: 10.1103/PhysRevLett.120.201801
    A search for narrow resonances decaying to bottom quark-antiquark pairs is presented, using a data sample of proton-proton collisions at sqrt[s]=8  TeV corresponding to an integrated luminosity of 19.7  fb^{-1}. The search is extended to masses lower than those reached in typical searches for resonances decaying into jet pairs at the LHC, by taking advantage of triggers that identify jets originating from bottom quarks. No significant excess of events is observed above the background predictions. Limits are set on the product of cross section and branching fraction to bottom quarks for spin 0, 1, and 2 resonances in the mass range of 325-1200 GeV. These results improve on the limits for resonances decaying into jet pairs in the 325-500 GeV mass range.
  18. Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Asilar E, Bergauer T, et al.
    Phys Rev Lett, 2018 Dec 14;121(24):241802.
    PMID: 30608761 DOI: 10.1103/PhysRevLett.121.241802
    Three of the most significant measured deviations from standard model predictions, the enhanced decay rate for B→D^{(*)}τν, hints of lepton universality violation in B→K^{(*)}ℓℓ decays, and the anomalous magnetic moment of the muon, can be explained by the existence of leptoquarks (LQs) with large couplings to third-generation quarks and masses at the TeV scale. The existence of these states can be probed at the LHC in high energy proton-proton collisions. A novel search is presented for pair production of LQs coupled to a top quark and a muon using data at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 35.9  fb^{-1}, recorded by the CMS experiment. No deviation from the standard model prediction has been observed and scalar LQs decaying exclusively into tμ are excluded up to masses of 1420 GeV. The results of this search are combined with those from previous searches for LQ decays into tτ and bν, which excluded scalar LQs below masses of 900 and 1080 GeV. Vector LQs are excluded up to masses of 1190 GeV for all possible combinations of branching fractions to tμ, tτ and bν. With this analysis, all relevant couplings of LQs with an electric charge of -1/3 to third-generation quarks are probed for the first time.
  19. Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Asilar E, Bergauer T, et al.
    Phys Rev Lett, 2018 Dec 14;121(24):242301.
    PMID: 30608764 DOI: 10.1103/PhysRevLett.121.242301
    Measurements of fragmentation functions for jets associated with an isolated photon are presented for the first time in pp and Pb-Pb collisions. The analysis uses data collected with the CMS detector at the CERN LHC at a nucleon-nucleon center-of-mass energy of 5.02 TeV. Fragmentation functions are obtained for jets with p_{T}^{jet}>30  GeV/c in events containing an isolated photon with p_{T}^{γ}>60  GeV/c, using charged tracks with transverse momentum p_{T}^{trk}>1  GeV/c in a cone around the jet axis. The association with an isolated photon constrains the initial p_{T} and azimuthal angle of the parton whose shower produced the jet. For central Pb-Pb collisions, modifications of the jet fragmentation functions are observed when compared to those measured in pp collisions, while no significant differences are found in the 50% most peripheral collisions. Jets in central Pb-Pb events show an excess (depletion) of low (high) p_{T} particles, with a transition around 3  GeV/c. This measurement shows for the first time the in-medium shower modifications of partons (quark dominated) with well-defined initial kinematics. It constitutes a new well-controlled reference for testing theoretical models of the parton passage through the quark-gluon plasma.
  20. Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Asilar E, Bergauer T, et al.
    Phys Rev Lett, 2018 Nov 30;121(22):221802.
    PMID: 30547617 DOI: 10.1103/PhysRevLett.121.221802
    The first evidence of events consistent with the production of a single top quark in association with a photon is reported. The analysis is based on proton-proton collisions at sqrt[s]=13  TeV and recorded by the CMS experiment in 2016, corresponding to an integrated luminosity of 35.9  fb^{-1}. Events are selected by requiring the presence of a muon (μ), a photon (γ), an imbalance in transverse momentum from an undetected neutrino (ν), and at least two jets (j) of which exactly one is identified as associated with the hadronization of a b quark. A multivariate discriminant based on topological and kinematic event properties is employed to separate signal from background processes. An excess above the background-only hypothesis is observed, with a significance of 4.4 standard deviations. A fiducial cross section is measured for isolated photons with transverse momentum greater than 25 GeV in the central region of the detector. The measured product of the cross section and branching fraction is σ(pp→tγj)B(t→μνb)=115±17(stat)±30(syst)  fb, which is consistent with the standard model prediction.
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