Displaying publications 1 - 20 of 200 in total

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  1. Wu J, Cai G, Fan Y, Arima K, Lin Y, Wong L, et al.
    Vaccines (Basel), 2023 Jan 11;11(1).
    PMID: 36680002 DOI: 10.3390/vaccines11010157
    Background: This study aimed to survey the attitudes toward COVID-19 vaccines and their acceptability among the Japanese public as soon as the United States Food and Drug Administration (FDA) authorized vaccines and their rollouts started around the world. Methods: An anonymous cross-sectional survey was conducted in Japan between 4 January and 5 March 2021. A questionnaire was administered to evaluate attitudes toward COVID-19 vaccines according to demographic characteristics, vaccine characteristics, and vaccine production. Results: A total of 1037 completed responses were received. More than half (63.5%) of the participants responded positively (extremely likely/likely) toward COVID-19 vaccines. The highest acceptance to be vaccinated was discovered among the youngest age group. As expected, participants who had never delayed acceptance or refused the vaccine in their history of vaccination had a significantly higher willingness to be vaccinated against COVID-19 (p < 0.001). Females (OR = 2.66, 95% CI: 1.99−3.58) and participants who had ever delayed acceptance or refuse the vaccine (OR = 3.49, 95% CI: 2.42−5.05) had higher odds of COVID-19 vaccine hesitancy. Participants with a postgraduate degree (OR = 0.64, 95% CI: 0.40−1.00) presented the highest willingness to be vaccinated against COVID-19. More than two-thirds (72.9%, 95% CI: 70.4%−75.8%) of the participants did not mind a booster dose required following primary vaccination. A total of 63.2% (95% CI: 60.0%−66.0%) of the participants only accepted a nearly 90% effective or above vaccine at preventing COVID-19. At the same, 86.4% (95% CI: 84.4%−88.4%) of the participants reported only accepting a vaccine with minor side effects. Conclusions: The moderate levels of COVID-19 vaccine acceptance found in the early phase of the pandemic demonstrate that it is important to improve the implementation of effective management for vaccine promotion and the acceptability of the vaccine to slow or delay transmission.
  2. Zhao P, Wang Y, Zhang Y, Guo T, Zhang Z, Zhang WJ, et al.
    Saudi J Biol Sci, 2016 May;23(3):353-7.
    PMID: 27081360 DOI: 10.1016/j.sjbs.2015.08.007
    In this study, the selenium enriched peanuts and the different solubility proteins extracted from them were investigated. The dried defatted selenium enriched peanuts (SeP) powder (0.3147 μg/g) had a 2.5-fold higher mean total selenium concentration than general peanuts (GP) power (0.1233 μg/g). The SeP had higher concentration of selenium, manganese and zinc than that of GP, but less calcium. The rate of extraction of protein was 23.39% for peanuts and alkali soluble protein was the main component of protein in SeP, which accounted for 92.82% of total soluble protein and combined selenium was 77.33% of total selenium protein. In different forms of proteins from SeP, the WSePr due to higher concentration of selenium had higher DPPH free-radical scavenging activity, higher reducing activity and longer induction time than other proteins.
  3. Yeo AL, Kandane-Rathnayake R, Koelmeyer R, Golder V, Louthrenoo W, Chen YH, et al.
    Rheumatology (Oxford), 2024 Feb 01;63(2):525-533.
    PMID: 37208196 DOI: 10.1093/rheumatology/kead231
    OBJECTIVE: Disease activity monitoring in SLE includes serial measurement of anti-double stranded-DNA (dsDNA) antibodies, but in patients who are persistently anti-dsDNA positive, the utility of repeated measurement is unclear. We investigated the usefulness of serial anti-dsDNA testing in predicting flare in SLE patients who are persistently anti-dsDNA positive.

    METHODS: Data were analysed from patients in a multinational longitudinal cohort with known anti-dsDNA results from 2013 to 2021. Patients were categorized based on their anti-dsDNA results as persistently negative, fluctuating or persistently positive. Cox regression models were used to examine longitudinal associations of anti-dsDNA results with flare.

    RESULTS: Data from 37 582 visits of 3484 patients were analysed. Of the patients 1029 (29.5%) had persistently positive anti-dsDNA and 1195 (34.3%) had fluctuating results. Anti-dsDNA expressed as a ratio to the normal cut-off was associated with the risk of subsequent flare, including in the persistently positive cohort (adjusted hazard ratio [HR] 1.56; 95% CI: 1.30, 1.87; P 3. Both increases and decreases in anti-dsDNA more than 2-fold compared with the previous visit were associated with increased risk of flare in the fluctuating cohort (adjusted HR 1.33; 95% CI: 1.08, 1.65; P = 0.008) and the persistently positive cohort (adjusted HR 1.36; 95% CI: 1.08, 1.71; P = 0.009).

    CONCLUSION: Absolute value and change in anti-dsDNA titres predict flares, including in persistently anti-dsDNA positive patients. This indicates that repeat monitoring of dsDNA has value in routine testing.

  4. Kandane-Rathnayake R, Louthrenoo W, Golder V, Luo SF, Wu YJ, Lateef A, et al.
    Rheumatology (Oxford), 2021 Nov 03;60(11):5185-5193.
    PMID: 33693676 DOI: 10.1093/rheumatology/keab217
    OBJECTIVE: The prevalence and associations of leucopenia in SLE remain incompletely understood. We evaluated associations of disease activity and medication use with leucopenia (lymphopenia and neutropenia) in a multinational, prospectively followed SLE cohort.

    METHODS: Data from the Asia Pacific Lupus Collaboration cohort, in which disease activity and medications were prospectively captured from 2013 to 2018, were used. Predictors of lymphopenia (lymphocyte count <0.8 × 109/l) and neutropenia (neutrophil count <1.5 × 109/l) were examined using multiple failure, time-dependent survival analyses.

    RESULTS: Data from 2330 patients and 18 287 visits were analysed. One thousand and eighteen patients (43.7%) had at least one episode of leucopenia; 867 patients (37.2%) had lymphopenia, observed in 3065 (16.8%) visits, and 292 (12.5%) patients had neutropenia, in 622 (3.4%) visits. After multivariable analyses, lymphopenia was associated with overall disease activity, ESR, serology, prednisolone, AZA, MTX, tacrolimus, CYC and rituximab use. MTX and ciclosporin were negatively associated with neutropenia. Lupus low disease activity state was negatively associated with both lymphopenia and neutropenia.

    CONCLUSION: Both lymphopenia and neutropenia were common in SLE patients but were differentially associated with disease and treatment variables. Lymphopenia and neutropenia should be considered independently in studies in SLE.

  5. Golder V, Kandane-Rathnayake R, Louthrenoo W, Chen YH, Cho J, Lateef A, et al.
    J Rheumatol, 2024 May 01.
    PMID: 38490668 DOI: 10.3899/jrheum.2023-0900
    OBJECTIVE: To assess whether Lupus Low Disease Activity State (LLDAS) attainment is associated with favorable outcomes in patients with recent onset systemic lupus erythematosus (SLE).

    METHODS: Data from a 13-country longitudinal SLE cohort were collected prospectively between 2013 and 2020. An inception cohort was defined based on disease duration < 1 year at enrollment. Patient characteristics between inception and noninception cohorts were compared. Survival analyses were performed to examine the association between LLDAS attainment and damage accrual and flare.

    RESULTS: Of the total 4106 patients, 680 (16.6%) were recruited within 1 year of SLE diagnosis (inception cohort). Compared to the noninception cohort, inception cohort patients were significantly younger, had higher disease activity, and used more glucocorticoids, but had less organ damage at enrollment. Significantly fewer inception cohort patients were in LLDAS at enrollment than the noninception cohort (29.6% vs 52.3%, P < 0.001), but three-quarters of both groups achieved LLDAS at least once during follow-up. Limiting analysis only to patients not in LLDAS at enrollment, inception cohort patients were 60% more likely to attain LLDAS (hazard ratio 1.37, 95% CI 1.16-1.61, P < 0.001) than noninception cohort patients and attained LLDAS significantly faster. LLDAS attainment was significantly protective against flare in both the inception and noninception cohorts. A total of 88 (13.6%) inception cohort patients accrued organ damage during a median 2.2 years of follow-up.

    CONCLUSION: LLDAS attainment is protective from flare in recent onset SLE. Significant protection from damage accrual was not observed because of low rates of damage accrual in the first years after SLE diagnosis. (ClinicalTrials.gov: NCT03138941).

  6. Kandane-Rathnayake R, Louthrenoo W, Luo SF, Wu YJ, Chen YH, Golder V, et al.
    Arthritis Care Res (Hoboken), 2022 Dec;74(12):2033-2041.
    PMID: 34197023 DOI: 10.1002/acr.24740
    OBJECTIVE: Evidence for the utility of medications in settings lacking randomized trial data can come from studies of treatment persistence. The present study was undertaken to examine patterns of medication use in systemic lupus erythematosus (SLE) using data from a large multicenter longitudinal cohort.

    METHODS: Prospectively collected data from the Asia Pacific Lupus Collaboration cohort including disease activity (SLE Disease Activity Index 2000 [SLEDAI-2K]) and medication details, captured at every visit from 2013-2018, were used. Medications were categorized as glucocorticoids (GCs), antimalarials (AM), and immunosuppressants (IS). Cox regression analyses were performed to determine the time-to-discontinuation of medications, stratified by SLE disease activity.

    RESULTS: Data from 19,804 visits of 2,860 patients were analyzed. Eight medication categories were observed: no treatment; GC, AM, or IS only; GC plus AM; GC plus IS; AM plus IS; and GC plus AM plus IS (triple therapy). Triple therapy was the most frequent pattern (31.4% of visits); single agents were used in 21% of visits, and biologics in only 3%. Time-to-discontinuation analysis indicated that medication persistence varied widely, with the highest treatment persistence for AM and lowest for IS. Patients with a time-adjusted mean SLEDAI-2K score of ≥10 had lower discontinuation of GCs and higher discontinuation of IS.

    CONCLUSION: Most patients received combination treatment. GC persistence was high, while IS persistence was low. Patients with high disease activity received more medication combinations but had reduced IS persistence, consistent with limited utility. These data confirm unmet need for improved SLE treatments.

  7. Kandane-Rathnayake R, Golder V, Louthrenoo W, Chen YH, Cho J, Lateef A, et al.
    Lancet Rheumatol, 2022 Dec;4(12):e822-e830.
    PMID: 38261390 DOI: 10.1016/S2665-9913(22)00304-6
    BACKGROUND: Treat-to-target goals for patients with systemic lupus erythematosus (SLE) have been validated to protect against organ damage and to improve quality of life. We aimed to investigate the association between lupus low disease activity state (LLDAS) and remission and risk of mortality in patients with SLE. We hypothesised that LLDAS has a protective association with mortality risk.

    METHODS: In this prospective, multinational, longitudinal cohort study, we used data from patients with SLE in the Asia Pacific Lupus Collaboration cohort collected between May 1, 2013, and Dec 31, 2020. Eligible patients were adults (aged ≥18 years) who met either the 1997 American College of Rheumatology modified classification criteria for SLE or the 2012 Systemic Lupus International Collaborating Clinics classification criteria. The primary outcome was all-cause mortality, and LLDAS, remission, and variations of remission with lower glucocorticoid thresholds were the primary exposure variables. Survival analyses were used to examine longitudinal associations between these endpoints and risk of mortality. This study is registered with ClinicalTrials.gov, NCT03138941.

    FINDINGS: Among a total of 4106 patients in the cohort, 3811 (92·8%) patients were included in the final analysis (median follow-up 2·8 years [IQR 1·0-5·3]; 3509 [92·1%] women and 302 [7·9%] men), of whom 80 died during the observation period (crude mortality rate 6·4 deaths per 1000 person-years). LLDAS was attained at least once in 43 (53·8%) of 80 participants who died and in 3035 (81·3%) of 3731 participants who were alive at the end of the study (p<0·0001); 22 (27·5%) participants who died versus 1966 (52·7%) who were alive at the end of the study attained LLDAS for at least 50% of observed time (p<0·0001). Remission was attained by 32 (40·0%) of 80 who died and in 2403 (64·4%) of 3731 participants who were alive at the end of the study (p<0·0001); 14 (17·5%) participants who died versus 1389 (37·2%) who were alive at the end of the study attained remission for at least 50% of observed time (p<0·0001). LLDAS for at least 50% of observed time (adjusted hazard ratio 0·51 [95% CI 0·31-0·85]; p=0·010) and remission for at least 50% of observed time (0·52 [0·29-0·93]; p=0·027) were associated with reduced risk of mortality. Modifying the remission glucocorticoid threshold (<5·0 mg/day prednisolone) was more protective against mortality than current remission definitions (0·31 [0·12-0·77]; p=0·012), and glucocorticoid-free remission was the most protective (0·13 [0·02-0·96]; p=0·046).

    INTERPRETATION: LLDAS significantly reduced the risk of mortality in patients with SLE. Remission did not further reduce the risk of mortality compared with LLDAS, unless lower glucocorticoid thresholds were used.

    FUNDING: The Asia-Pacific Lupus Collaboration received funding from Janssen, Bristol Myers Squibb, Eli Lilly, and UCB for this study.

  8. Connelly K, Kandane-Rathnayake R, Hoi A, Louthrenoo W, Hamijoyo L, Cho J, et al.
    Lancet Rheumatol, 2022 Dec;4(12):e831-e841.
    PMID: 38261391 DOI: 10.1016/S2665-9913(22)00307-1
    BACKGROUND: The selection and categorisation of laboratory tests in disease activity measures used within systemic lupus erythematosus (SLE) trial endpoints lack strong evidence. We aimed to determine whether longitudinal improvements in routinely measured laboratory tests are associated with measures of clinical improvement in patients with baseline active SLE.

    METHODS: We included patients from a multicentre longitudinal cohort (recruited between May 1, 2013, and Dec 31, 2019) with active SLE (SLEDAI-2K ≥6) coinciding with an abnormality in at least one of 13 routine laboratory tests, at a visit designated as baseline. At 12 months, we analysed associations between thresholds of improvement in individual laboratory test results, measured as continuous variables, and five clinical outcomes using logistic regression. Primary outcomes were damage accrual and lupus low disease activity state (LLDAS), and secondary outcomes were modified SLE responder index (mSRI), physician global assessment (PGA) improvement of at least 0·3, and flare.

    FINDINGS: We included 1525 patients (1415 [93%] women and 110 [7%] men, 1328 [87%] Asian ethnicity) in separate subsets for each laboratory test. The strongest associations with LLDAS and damage protection were seen with improvements in proteinuria (complete response: adjusted odds ratio [OR] 62·48, 95% CI 18·79-208·31 for LLDAS, OR 0·22, 95% CI 0·10-0·49 for damage accrual), albumin (complete response: adjusted OR 6·46, 95% CI 2·20-18·98 for LLDAS, OR 0·42, 95% CI 0·20-1·22 for damage accrual), haemoglobin (complete response: adjusted OR 1·97, 95% CI 1·09-3·53 for LLDAS, OR 0·33, 95% CI 0·15-0·71 for damage accrual), erythrocyte sedimentation rate (complete response: adjusted OR 1·71, 95% CI 1·10-2·67 for LLDAS, OR 0·53, 95% CI 0·30-0·94 for damage accrual), and platelets (complete response: adjusted OR 4·82, 95% CI 1·54-15·07 for LLDAS, OR 0·49, 95% CI 0·20-1·19 for damage accrual). Improvement in serological tests were mainly associated with PGA and mSRI. White cell and lymphocyte count improvements were least predictive.

    INTERPRETATION: Improvements in several routine laboratory tests correspond with clinical outcomes in SLE over 12 months. Tests with the strongest associations were discrepant with laboratory tests included in current trial endpoints, and associations were observed across a range of improvement thresholds including incomplete resolution. These findings suggest the need to revise the use of laboratory test results in SLE trial endpoints.

    FUNDING: Abbvie.

  9. Cho J, Shen L, Huq M, Kandane-Rathnayake R, Golder V, Louthrenoo W, et al.
    Lancet Rheumatol, 2023 Oct;5(10):e584-e593.
    PMID: 38251484 DOI: 10.1016/S2665-9913(23)00209-6
    BACKGROUND: Targets of treatment for systemic lupus erythematosus (SLE) include the Lupus Low Disease Activity State (LLDAS), remission, and complete remission. Whether treatment can be tapered after attaining these targets and whether tapering is safer in patients in complete remission compared with LLDAS are unknown. We aimed to assess the odds of disease flares after treatment tapering in stable disease, versus continuing the same therapy. We also aimed to examine whether tapering in complete remission resulted in fewer flares or longer time to flare compared with tapering in LLDAS or remission.

    METHODS: This multinational cohort study was conducted at 25 sites across 13 Asia-Pacific countries. We included adult patients aged 18 years or older with stable SLE who were receiving routine clinical care, had two or more visits and had attained stable disease at one or more visits. We categorised stable disease into: LLDAS (Systemic Lupus Erythematosus Disease Activity Index 2000 [SLEDAI-2K] score ≤4, Physician Global Assessment [PGA] ≤1, and prednisolone ≤7·5 mg/day); Definitions of Remission in SLE (DORIS) remission (clinical SLEDAI-2K score 0, PGA <0·5, and prednisolone ≤5 mg/day); or complete remission on therapy (SLEDAI-2K score 0, PGA <0·5, and prednisolone ≤5 mg/day). Stable disease categories were mutually exclusive. Tapering was defined as any decrease in dose of corticosteroids or immunosuppressive therapy (mycophenolate mofetil, calcineurin inhibitors, azathioprine, leflunomide, or methotrexate). Using multivariable generalised estimating equations, we compared flares (SELENA-SLEDAI Flare Index) at the subsequent visit after drug tapering. We used generalised estimating equations and Cox proportional hazard models to compare tapering attempts that had begun in LLDAS, remission, and complete remission.

    FINDINGS: Between May 1, 2013, and Dec 31, 2020, 4106 patients were recruited to the cohort, 3002 (73·1%) of whom were included in our analysis. 2769 (92·2%) participants were female, 233 (7·8%) were male, and 2636 (88·1%) of 2993 with ethnicity data available were Asian. The median age was 39·5 years (IQR 29·0-50·0). There were 14 808 patient visits for patients in LLDAS, or remission or complete remission, of which 13 140 (88·7%) entered the final multivariable model after excluding missing data. Among the 9863 visits at which patients continued the same therapy, 1121 (11·4%) flared at the next visit, of which 221 (19·7%) were severe flares. Of the 3277 visits at which a patient received a tapering of therapy, 557 (17·0%) flared at the next visit, of which 120 (21·5%) were severe flares. Tapering was associated with higher odds of flare compared with continuing the same therapy (odds ratio [OR] 1·24 [95% CI 1·10-1·39]; p=0·0005). Of 2095 continuous tapering attempts, 860 (41·1%) were initiated in LLDAS, 596 (28·4%) in remission, and 639 (30·5%) in complete remission. Tapering initiated in LLDAS (OR 1·37 [95% CI 1·03-1·81]; p=0·029) or remission (1·45 [1·08-1·94]; p=0·013) had higher odds of flare in 1 year compared with complete remission. Tapering in LLDAS (hazard ratio 1·24 [95% CI 1·04-1·48]; p=0·016) or remission (1·30 [1·08-1·56]; p=0·0054) had a significantly shorter time to first flare than tapering initiated in complete remission. Attaining sustained LLDAS, remission, or complete remission for at least 6 months just before the time of taper was associated with lower odds of flare at next visit, flares in 1 year, and longer time to flare.

    INTERPRETATION: Tapering of corticosteroids or immunosuppressive therapy in patients with stable SLE was associated with excess flares. Our findings suggest that drug tapering should be carefully considered, weighing the risks and benefits, and is best exercised in complete (clinical and serological) remission and after maintaining stable disease for at least 6 months.

    FUNDING: AstraZeneca, BMS, Eli Lily, Janssen, Merck Serono, GSK, and UCB.

  10. Katsumata Y, Inoue E, Harigai M, Cho J, Louthrenoo W, Hoi A, et al.
    Ann Rheum Dis, 2024 Feb 29.
    PMID: 38423757 DOI: 10.1136/ard-2023-225369
    OBJECTIVES: To assess the risk of flare and damage accrual after tapering glucocorticoids (GCs) in modified serologically active clinically quiescent (mSACQ) patients with systemic lupus erythematosus (SLE).

    METHODS: Data from a 12-country longitudinal SLE cohort, collected prospectively between 2013 and 2020, were analysed. SLE patients with mSACQ defined as the state with serological activity (increased anti-dsDNA and/or hypocomplementemia) but without clinical activity, treated with ≤7.5 mg/day of prednisolone-equivalent GCs and not-considering duration, were studied. The risk of subsequent flare or damage accrual per 1 mg decrease of prednisolone was assessed using Cox proportional hazard models while adjusting for confounders. Observation periods were 2 years and censored if each event occurred.

    RESULTS: Data from 1850 mSACQ patients were analysed: 742, 271 and 180 patients experienced overall flare, severe flare and damage accrual, respectively. Tapering GCs by 1 mg/day of prednisolone was not associated with increased risk of overall or severe flare: adjusted HRs 1.02 (95% CI, 0.99 to 1.05) and 0.98 (95% CI, 0.96 to 1.004), respectively. Antimalarial use was associated with decreased flare risk. Tapering GCs was associated with decreased risk of damage accrual (adjusted HR 0.96, 95% CI, 0.93 to 0.99) in the patients whose initial prednisolone dosages were >5 mg/day.

    CONCLUSIONS: In mSACQ patients, tapering GCs was not associated with increased flare risk. Antimalarial use was associated with decreased flare risk. Tapering GCs protected mSACQ patients treated with >5 mg/day of prednisolone against damage accrual. These findings suggest that cautious GC tapering is feasible and can reduce GC use in mSACQ patients.

  11. Fulsom BG, Pedlar TK, Adachi I, Aihara H, Al Said S, Asner DM, et al.
    Phys Rev Lett, 2018 Dec 07;121(23):232001.
    PMID: 30576207 DOI: 10.1103/PhysRevLett.121.232001
    We report the observation of ϒ(2S)→γη_{b}(1S) decay based on an analysis of the inclusive photon spectrum of 24.7  fb^{-1} of e^{+}e^{-} collisions at the ϒ(2S) center-of-mass energy collected with the Belle detector at the KEKB asymmetric-energy e^{+}e^{-} collider. We measure a branching fraction of B[ϒ(2S)→γη_{b}(1S)]=(6.1_{-0.7-0.6}^{+0.6+0.9})×10^{-4} and derive an η_{b}(1S) mass of 9394.8_{-3.1-2.7}^{+2.7+4.5}  MeV/c^{2}, where the uncertainties are statistical and systematic, respectively. The significance of our measurement is greater than 7 standard deviations, constituting the first observation of this decay mode.
  12. Adachi I, Adye T, Ahmed H, Ahn JK, Aihara H, Akar S, et al.
    Phys Rev Lett, 2018 Dec 28;121(26):261801.
    PMID: 30636113 DOI: 10.1103/PhysRevLett.121.261801
    We present first evidence that the cosine of the CP-violating weak phase 2β is positive, and hence exclude trigonometric multifold solutions of the Cabibbo-Kobayashi-Maskawa (CKM) Unitarity Triangle using a time-dependent Dalitz plot analysis of B^{0}→D^{(*)}h^{0} with D→K_{S}^{0}π^{+}π^{-} decays, where h^{0}∈{π^{0},η,ω} denotes a light unflavored and neutral hadron. The measurement is performed combining the final data sets of the BABAR and Belle experiments collected at the ϒ(4S) resonance at the asymmetric-energy B factories PEP-II at SLAC and KEKB at KEK, respectively. The data samples contain (471±3)×10^{6}BB[over ¯] pairs recorded by the BABAR detector and (772±11)×10^{6}BB[over ¯] pairs recorded by the Belle detector. The results of the measurement are sin2β=0.80±0.14(stat)±0.06(syst)±0.03(model) and cos2β=0.91±0.22(stat)±0.09(syst)±0.07(model). The result for the direct measurement of the angle β of the CKM Unitarity Triangle is β=[22.5±4.4(stat)±1.2(syst)±0.6(model)]°. The measurement assumes no direct CP violation in B^{0}→D^{(*)}h^{0} decays. The quoted model uncertainties are due to the composition of the D^{0}→K_{S}^{0}π^{+}π^{-} decay amplitude model, which is newly established by performing a Dalitz plot amplitude analysis using a high-statistics e^{+}e^{-}→cc[over ¯] data sample. CP violation is observed in B^{0}→D^{(*)}h^{0} decays at the level of 5.1 standard deviations. The significance for cos2β>0 is 3.7 standard deviations. The trigonometric multifold solution π/2-β=(68.1±0.7)° is excluded at the level of 7.3 standard deviations. The measurement resolves an ambiguity in the determination of the apex of the CKM Unitarity Triangle.
  13. Li YB, Shen CP, Yuan CZ, Adachi I, Aihara H, Al Said S, et al.
    Phys Rev Lett, 2019 Mar 01;122(8):082001.
    PMID: 30932568 DOI: 10.1103/PhysRevLett.122.082001
    We present the first measurements of absolute branching fractions of Ξ_{c}^{0} decays into Ξ^{-}π^{+}, ΛK^{-}π^{+}, and pK^{-}K^{-}π^{+} final states. The measurements are made using a dataset comprising (772±11)×10^{6} BB[over ¯] pairs collected at the ϒ(4S) resonance with the Belle detector at the KEKB e^{+}e^{-} collider. We first measure the absolute branching fraction for B^{-}→Λ[over ¯]_{c}^{-}Ξ_{c}^{0} using a missing-mass technique; the result is B(B^{-}→Λ[over ¯]_{c}^{-}Ξ_{c}^{0})=(9.51±2.10±0.88)×10^{-4}. We subsequently measure the product branching fractions B(B^{-}→Λ[over ¯]_{c}^{-}Ξ_{c}^{0})B(Ξ_{c}^{0}→Ξ^{-}π^{+}), B(B^{-}→Λ[over ¯]_{c}^{-}Ξ_{c}^{0})B(Ξ_{c}^{0}→ΛK^{-}π^{+}), and B(B^{-}→Λ[over ¯]_{c}^{-}Ξ_{c}^{0})B(Ξ_{c}^{0}→pK^{-}K^{-}π^{+}) with improved precision. Dividing these product branching fractions by the result for B^{-}→Λ[over ¯]_{c}^{-}Ξ_{c}^{0} yields the following branching fractions: B(Ξ_{c}^{0}→Ξ^{-}π^{+})=(1.80±0.50±0.14)%, B(Ξ_{c}^{0}→ΛK^{-}π^{+})=(1.17±0.37±0.09)%, and B(Ξ_{c}^{0}→pK^{-}K^{-}π^{+})=(0.58±0.23±0.05)%. For the above branching fractions, the first uncertainties are statistical and the second are systematic. Our result for B(Ξ_{c}^{0}→Ξ^{-}π^{+}) can be combined with Ξ_{c}^{0} branching fractions measured relative to Ξ_{c}^{0}→Ξ^{-}π^{+} to yield other absolute Ξ_{c}^{0} branching fractions.
  14. Seong IS, Vahsen SE, Adachi I, Aihara H, Al Said S, Asner DM, et al.
    Phys Rev Lett, 2019 Jan 11;122(1):011801.
    PMID: 31012694 DOI: 10.1103/PhysRevLett.122.011801
    We report on the first Belle search for a light CP-odd Higgs boson, A^{0}, that decays into low mass dark matter, χ, in final states with a single photon and missing energy. We search for events produced via the dipion transition ϒ(2S)→ϒ(1S)π^{+}π^{-}, followed by the on-shell process ϒ(1S)→γA^{0} with A^{0}→χχ, or by the off-shell process ϒ(1S)→γχχ. Utilizing a data sample of 157.3×10^{6} ϒ(2S) decays, we find no evidence for a signal. We set limits on the branching fractions of such processes in the mass ranges M_{A^{0}}<8.97  GeV/c^{2} and M_{χ}<4.44  GeV/c^{2}. We then use the limits on the off-shell process to set competitive limits on WIMP-nucleon scattering in the WIMP mass range below 5  GeV/c^{2}.
  15. Sibidanov A, Varvell KE, Adachi I, Aihara H, Al Said S, Asner DM, et al.
    Phys Rev Lett, 2018 Jul 20;121(3):031801.
    PMID: 30085771 DOI: 10.1103/PhysRevLett.121.031801
    We report the results of a search for the rare, purely leptonic decay B^{-}→μ^{-}ν[over ¯]_{μ} performed with a 711  fb^{-1} data sample that contains 772×10^{6}  BB[over ¯] pairs, collected near the ϒ(4S) resonance with the Belle detector at the KEKB asymmetric-energy e^{+}e^{-} collider. The signal events are selected based on the presence of a high momentum muon and the topology of the rest of the event showing properties of a generic B-meson decay, as well as the missing energy and momentum being consistent with the hypothesis of a neutrino from the signal decay. We find a 2.4 standard deviation excess above background including systematic uncertainties, which corresponds to a branching fraction of B(B^{-}→μ^{-}ν[over ¯]_{μ})=(6.46±2.22±1.60)×10^{-7} or a frequentist 90% confidence level interval on the B^{-}→μ^{-}ν[over ¯]_{μ} branching fraction of [2.9,10.7]×10^{-7}.
  16. Guido E, Mussa R, Tamponi U, Aihara H, Al Said S, Asner DM, et al.
    Phys Rev Lett, 2018 Aug 10;121(6):062001.
    PMID: 30141661 DOI: 10.1103/PhysRevLett.121.062001
    We report the first observation of the hadronic transition ϒ(4S)→η^{'}ϒ(1S), using 496  fb^{-1} data collected at the ϒ(4S) resonance with the Belle detector at the KEKB asymmetric-energy e^{+}e^{-} collider. We reconstruct the η^{'} meson through its decays to ρ^{0}γ and to π^{+}π^{-}η, with η→γγ. We measure B(ϒ(4S)→η^{'}ϒ(1S))=[3.43±0.88(stat)±0.21(syst)]×10^{-5}, with a significance of 5.7σ.
  17. Guan Y, Vossen A, Adachi I, Adamczyk K, Ahn JK, Aihara H, et al.
    Phys Rev Lett, 2019 Feb 01;122(4):042001.
    PMID: 30768311 DOI: 10.1103/PhysRevLett.122.042001
    We report the first observation of the spontaneous polarization of Λ and Λ[over ¯] hyperons transverse to the production plane in e^{+}e^{-} annihilation, which is attributed to the effect arising from a polarizing fragmentation function. For inclusive Λ/Λ[over ¯] production, we also report results with subtracted feed-down contributions from Σ^{0} and charm. This measurement uses a dataset of 800.4  fb^{-1} collected by the Belle experiment at or near a center-of-mass energy of 10.58 GeV. We observe a significant polarization that rises with the fractional energy carried by the Λ/Λ[over ¯] hyperon.
  18. 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
  19. 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.
  20. 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^{±}.
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