Displaying publications 1 - 20 of 125 in total

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  1. Peng C
    Front Psychol, 2021;12:742970.
    PMID: 34539533 DOI: 10.3389/fpsyg.2021.742970
    The swift growth and progress of colleges and universities across China noticed a request for teaching and learning English as Foreign Language (EFL), and regarding the quality of higher education, student engagement has been at the center of attention which has a remarkable role due to the arrival of positive psychology in language learning recently. To this end, on the one hand, nurturing student engagement in EFL classes corresponds to requests from the recent national university English curriculum selected in 2015 in China. On the other hand, a bulk of studies has acknowledged difficulties that hinder the construction of a learner-centric learning situation. Moreover, there is a dearth of inquires which have focused on teachers' role in general and affective aspects namely enthusiasm, in particular. According to the literature review, the definition of these constructs, namely teacher enthusiasm and students' success and engagement are presented. In a nutshell, the implications for teachers, university administrators, teacher-trainers, and future researchers are presented, and new directions for future research are allocated.
  2. Peng C
    Front Psychol, 2021;12:778174.
    PMID: 34777184 DOI: 10.3389/fpsyg.2021.778174
    Given the undeniable role of English as a foreign language (EFL) students' academic motivation and engagement in L2 success, identifying the antecedents of these positive academic behaviors seems essential. Accordingly, many empirical studies have probed into the impact of students' personal factors on their motivation and engagement. Yet, not much attention has been paid to the role of teachers' communication behaviors, notably praise. Additionally, no review has been performed in this regard. The present review study intends to address these gaps by explaining teacher praise and its positive outcomes for EFL students' motivation and engagement. In light of the empirical and theoretical evidence, the role of teacher praise in improving students' academic motivation and engagement was proved. The paper concludes with some pedagogical implications.
  3. Tan PC, Omar SZ
    Curr Opin Obstet Gynecol, 2011 Apr;23(2):87-93.
    PMID: 21297474 DOI: 10.1097/GCO.0b013e328342d208
    PURPOSE OF REVIEW: Nausea and vomiting of pregnancy (NVP) affects 90% of pregnant women and its impact is often underappreciated. Hyperemesis gravidarum, the most severe end of the spectrum, affects 0.5-2% of pregnancies. The pathogenesis of this condition remains obscure and its management has largely been empirical. This review aims to provide an update on advances in pregnancy hyperemesis focusing on papers published within the past 2 years.

    RECENT FINDINGS: The cause of hyperemesis is continuing to be elaborated. Recent data attest to the effectiveness of the oral doxylamine-pyridoxine in NVP. Follow-up data of children exposed in early pregnancy to doxylamine-pyridoxine for NVP are reassuring. Evidence is increasing for ginger as an effective herbal remedy for NVP. Metoclopramide is effective in NVP and hyperemesis gravidarum, with a good balance of efficacy and tolerability. A recent large-scale study on first trimester exposure to metoclopramide is reassuring of its safety. Evidence is emerging for the treatment of acid reflux to ameliorate NVP. The role of corticosteroids for hyperemesis gravidarum remains controversial. Transpyloric feeding may be warranted for persistent weight loss, despite optimal antiemetic therapy.

    SUMMARY: Women with significant NVP should be identified so that they can be safely and effectively treated.

  4. Tan PC, Mubarak S, Omar SZ
    J Obstet Gynaecol Res, 2008 Aug;34(4):512-7.
    PMID: 18937705 DOI: 10.1111/j.1447-0756.2008.00815.x
    AIM:
    To evaluate the relationship between gamma-glutamyltransferase (GGT) level in pregnant women at oral glucose tolerance test (OGTT) and the diagnosis of gestational diabetes (GDM).

    METHODS:
    Blood was taken for analyzing GGT level from women at high risk of GDM at the time of their scheduled OGTT. GDM was diagnosed according to World Health Organization 1999 criteria.

    RESULTS:
    GGT level correlated positively with the 2-hour glucose level (Spearman's rho = 0.112: P < 0.05). GGT values that were stratified into quartiles demonstrated a significant trend with diagnosis of GDM (chi(2) for trend; P = 0.03). Multivariable logistic regression analysis taking into account maternal age, gestational age at OGTT, body mass index and a positive 50-g glucose challenge test (GCT) indicated that high GGT was an independent risk factor for GDM (adjusted odds ratio [AOR] 2.1 95% CI 1.2-3.8: P = 0.01). In the subset of women identified by a positive GCT, on multivariable logistic regression analysis, only high GGT was an independent risk factor for GDM (AOR 2.3 95% CI 1.3-4.2: P = 0.007).

    CONCLUSION:
    Raised GGT level is an independent risk factor for GDM in high risk pregnant women undergoing OGTT.
  5. Tan PC, Jacob R, Quek KF, Omar SZ
    J Obstet Gynaecol Res, 2007 Aug;33(4):457-64.
    PMID: 17688612
    To determine pregnancy outcome in hyperemesis gravidarum and the effect of metabolic, biochemical, hematological and clinical indicators of disease severity on outcome.
  6. Lim BK, Zakaria R, Hong JGS, Omar SZ, Sulaiman S, Tan PC
    J Obstet Gynaecol Res, 2022 Jan 23.
    PMID: 35068018 DOI: 10.1111/jog.15157
    AIM: To explore digital insertion in dorsal recumbent position of 16F, 22F, or 28F catheter bores on insertion failure, duration, and pain in unripe cervix labor induction.

    METHODS: A randomized trial was performed in a University hospital in Malaysia. Term women scheduled for labor induction, Bishop score ≤ 5, singleton, cephalic presentation, intact membrane, and reassuring pre-induction fetal heart rate tracing were recruited. Women with known gross fetal anomaly, allergy to latex and inability to consent or language difficulty were excluded. Participants were randomized to 16F, 22F, or 28F Foley catheter. Primary outcome was insertion failure and main secondary outcomes were insertion duration and pain (assessed by a Visual Numerical Rating Scale [VNRS] 0-10, higher score more pain). Analysis is done by analysis of variance (ANOVA), Kruskal-Wallis, and chi square test across the three arms and by t test and Mann-Whitney U test for pair wise comparisons.

    RESULTS: One hundred twenty-seven participants' data were analyzed. The insertion failure 7/43(16%) versus 4/42(10%) versus 5/42(12%), p = 0.64, insertion duration median [IQR] 2.8 [1.8-4.8] versus 2.8 [1.7-3.7] versus 2.8 [1.7-4.3] min, p = 0.68 and insertion pain VNRS mean {SD} 4.2 {2.5} versus 3.4 {2.3} versus 3.6 {2.2}, p = 0.26, insertion to delivery interval 26.0 {9.7} versus 25.6 {9.1} versus 22.8 {7.4} h, p = 0.45, and spontaneous vaginal delivery 20/43 (45%) versus 23/42(55%) versus 25/42(60%), p = 0.48 for 16F versus 22F versus 28F arms, respectively. Pairwise comparisons were not different.

    CONCLUSION: Foley catheter 16F versus 22F versus 28F resulted in similar digital insertion performance in the dorsal recumbent position for unripe cervix labor induction.

    CLINICAL TRIAL REGISTRATION: https://doi.org/10.1186/ISRCTN21224268.

  7. Tew MP, Tan PC, Saaid R, Hong JGS, Omar SZ
    Int J Gynaecol Obstet, 2022 Mar;156(3):508-515.
    PMID: 33890319 DOI: 10.1002/ijgo.13718
    OBJECTIVE: To evaluate the impact of preemptive metformin on the level of glycosylated hemoglobin (HbA1c) at 36 weeks of pregnancy in women with gestational diabetes mellitus controlled by diet change (GDMA1).

    METHODS: A randomized, double-blind, placebo-controlled trial was performed in a university hospital. Women with GDMA1 were recruited at 16-30 weeks of pregnancy and randomized to oral metformin 500 mg twice daily or identical placebo tablets to delivery. Level of HbA1c was taken at recruitment and at 36 weeks of pregnancy. The primary outcome was the change in level of HbA1c at recruitment and 36 weeks of pregnancy.

    RESULTS: Data from 106 participants were analyzed. The level of HbA1c during pregnancy increased significantly with a mean increase of 0.20% ± 0.31% (P 

  8. Ren D, Jiang H, Cheng J, Peng C, Zou Y
    Heliyon, 2023 Sep;9(9):e19200.
    PMID: 37662732 DOI: 10.1016/j.heliyon.2023.e19200
    Building on the upper echelons theory and demographic faultline theory, this paper investigates the role of the top management team (TMT) faultline as a mediator and explores the moderating effect of CEO power as an important contextual factor. We utilize a sample of A-share listed companies on the Shanghai and Shenzhen Stock Exchanges from 2009 to 2020. Our findings show that outside CEO successors are significantly and positively related to corporate strategic change. TMT faultline mediates the effect of CEO successor origins on corporate strategic change, while CEO power reinforces the relationship between the two. Heterogeneity tests reveal that the effect of outside CEO successors on strategic change is insignificant in state-owned enterprises (SOEs) but has a significant impact on firms at their growth and maturity stages. Furthermore, our findings suggest that outside CEO successors inhibit the positive role of strategic change in promoting firm value.
  9. Wong SC, Ooi MH, Abdullah AR, Wong SY, Krishnan S, Tio PH, et al.
    Trop Med Int Health, 2008 Jan;13(1):52-5.
    PMID: 18291002 DOI: 10.1111/j.1365-3156.2007.01967.x
    Japanese encephalitis virus (JEV) is an important encephalitis virus in Asia, but there are few data on Malaysia. A hospital-based surveillance system for Japanese encephalitis (JE) has been in operation in Sarawak, Malaysia, for the last 10 years. JEV is endemic in Sarawak, with cases occurring throughout the year and a seasonal peak in the last quarter (one-way anova, P < 0.0001). Ninety-two per cent of 133 cases were children aged 12 years or younger; the introduction of JE vaccination in July 2001 reduced the number of JE cases (84 in the four seasons prior to vs. 49 in the six seasons after, McNemar's test, P = 0.0001). After implementation of the programme, the mean age of infected children increased from 6.3 to 8.0 years (Student's t-test, P = 0.0037), suggesting the need for a catch-up programme.
  10. Peng C, Wu C, Gao L, Zhang J, Alvin Yau KL, Ji Y
    Sensors (Basel), 2020 Sep 07;20(18).
    PMID: 32906707 DOI: 10.3390/s20185079
    The vehicular Internet of Things (IoT) comprises enabling technologies for a large number of important applications including collaborative autonomous driving and advanced transportation systems. Due to the mobility of vehicles, strict application requirements, and limited communication resources, the conventional centralized control fails to provide sufficient quality of service for connected vehicles, so a decentralized approach is required in the vicinity to satisfy the requirements of delay-sensitive and mission-critical applications. A decentralized system is also more resistant to the single point of failure problem and malicious attacks. Blockchain technology has been attracting great interest due to its capability of achieving a decentralized, transparent, and tamper-resistant system. There are many studies focusing on the use of blockchain in managing data and transactions in vehicular environments. However, the application of blockchain in vehicular environments also faces some technical challenges. In this paper, we first explain the fundamentals of blockchain and vehicular IoT. Then, we conduct a literature review on the existing research efforts of the blockchain for vehicular IoT by discussing the research problems and technical issues. After that, we point out some future research issues considering the characteristics of both blockchain and vehicular IoT.
  11. Liu L, Sim SF, Lin S, Wan J, Zhang W, Li Q, et al.
    J Hazard Mater, 2021 Sep 05;417:126009.
    PMID: 34229376 DOI: 10.1016/j.jhazmat.2021.126009
    In this study, various HCl-supported hydrochar made from root powder of long-root Eichhornia crassipes were applied to adsorb aqueous sulfachloropyridazine (SCP). Adsorption capacity (qe μg g-1) was positively correlated with combined severity-CS. With CS increasing, carbonization degree, hydrophobicity, porosity and isoelectric point of hydrochar increased, but content of polar functional groups decreased. Hydrophobic interaction was important for SCP adsorption. A 24 × 36 peak area table was generated from 24 FT-IR absorbance spectra computed by peak detection algorithm. Afterwards, correlation analysis between qe μg g-1 and FT-IR peak area were conducted, indicating that wavenumbers at 555.4, 1227.47, 1374.51, 1604.5, 2901.4/2919.2 and 3514.63 cm-1 were helpful for SCP adsorption. Further, multivariate linear regression analyses showed that aromatic skeleton and phenolic hydroxyl were the two biggest contributors. Electrostatic attraction did not exist during the SCP adsorption process. Under strong acid condition, protonated amino groups in cationic SCP acting as a hydrogen donator interacted with electron-rich functional groups onto hydrochar by Hydrogen interaction. Under weak acid condition, neutral SCP served as an π electron donor to bond with hydrochar by π-π electron donator-acceptor interaction. This work could guide the functional groups modification strategy of hydrochar to make better use of it in water purification field.
  12. Wang Y, Li Y, Yang Y, Peng C, Fu X, Gu X, et al.
    Exp Ther Med, 2020 Jul;20(1):543-549.
    PMID: 32537012 DOI: 10.3892/etm.2020.8728
    The aim of the present study was to analyze the sequence of the VP1 gene in enterovirus 71 (EV71) isolates and to explore their genetic evolution, so as to provide a scientific basis for the clinical prevention and treatment of hand, foot and mouth disease. The fecal samples of 590 patients with suspected hand, foot and mouth disease treated at Yan'an Hospital (Kunming, China) between January 2015 and December 2016 were collected and EV71 nucleic acid was detected by fluorescence PCR. The viral RNA of EV71-positive samples was extracted, the VP1 gene was amplified by PCR and the products were sequenced. The VP1 gene sequence was analyzed using DNAMAN and MEGA (version 4.0) software and homologous modeling was performed using Pymol software. A total of 50 EV71-positive samples were identified and the detection rate was 8.47% (50/590 cases). All of the 50 EV71 strains were of the C4 subtype. The genetic distance between the strains detected in the present study and EV71 strains detected in Beijing, Anhui and Malaysia was 0.01-0.03, while that between the strains detected in the present study and Australian strains was 2.11. Homologous modeling indicated that the amino acid sequence of the VP1 gene of the detected strains had a H144Y mutation. There was no significant genetic variation in the EV71 strain within the 2-year period. In conclusion, the EV71 strains detected in the present study was similar to that detected in Beijing, Anhui and Malaysia but different to that from Australia. A point mutation was present in the amino acid sequence of the VP1 gene.
  13. Tian Y, Li P, Xiao Z, Zhou J, Xue X, Jiang N, et al.
    Transl Lung Cancer Res, 2021 Feb;10(2):1007-1019.
    PMID: 33718039 DOI: 10.21037/tlcr-21-145
    Background: Chemotherapy is one of the primary treatments for both small cell lung cancer (SCLC) and non-small cell lung cancer (NSCLC), however, chemoresistance develops over time and is a bottleneck to effective chemotherapy worldwide. Therefore, the development of new potent therapeutic agents to overcome chemoresistance is of utmost importance. Triptolide is a natural component extracted from Tripterygium Wilfordii, a Chinese plant; our study aimed to evaluate its anti-tumor effects in taxol-resistant human lung adenocarcinoma and investigate its molecular mechanisms of chemoresistance.

    Methods: Triptolide's inhibition of cell viability was detected by sulforhodamine B (SRB) assay. Cell cycle was measured by flow cytometry and cell apoptosis was assessed by flow cytometry and western blot. Expression of β-catenin was analyzed by western blot and immunofluorescence (IF). The anti-tumor effects of triptolide were determined using a subcutaneous in-vivo model. Cell proliferation and apoptosis were evaluated by immunohistochemistry (IHC) and terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) assay, respectively. The expression level of p-p70S6K and p-GSK-3α/β was evaluated by western blot and IHC.

    Results: Triptolide inhibited cell proliferation, induced S-phase cell cycle arrest and apoptosis in taxol-resistant A549 (A549/TaxR) cells. Moreover, intraperitoneal injection of triptolide resulted in a significant delay of tumor growth without obvious systemic toxicity in mice. Additionally, triptolide reversed epithelial-mesenchymal transition (EMT) through repression of the p70S6K/GSK3/β-catenin signaling pathway.

    Conclusions: Our study provides evidence that triptolide can reverse EMT in taxol-resistant lung adenocarcinoma cells and impairs tumor growth by inhibiting the p70S6K/GSK3/β-catenin pathway, indicating that triptolide has potential to be used as a new therapeutic agent for taxol-resistant lung adenocarcinoma.

  14. Huang Q, Gu L, Zhu J, Peng C, Du S, Liu Q, et al.
    Cancer, 2020 May 01;126 Suppl 9:2062-2072.
    PMID: 32293724 DOI: 10.1002/cncr.32748
    BACKGROUND: A quantitative nephrometry scoring system specifically for renal sinus tumors will assist in classifying surgical complexity and treatment planning.

    METHODS: By using preoperative computed tomography, magnetic resonance imaging, and 3-dimensional image reconstruction, 5 critical components were assessed: the ratio of the sinus area occupied by the tumor in relation to the whole sinus area (R), the compression of the renal segmental vessels or collection system by the tumor (O), the anteroposterior relation of the tumor relative to the segmental vessels or collection system (A), the tumor diameter (D), and whether the tumor affects a solitary kidney (S) ("ROADS"). The ROADS score, indicating low, moderate, or high surgical complexity, was then used to guide surgical strategy planning, including cooling techniques, surgical approaches, and parenchyma incision techniques. A cohort of 134 patients with renal sinus tumors was treated based on their ROADS score and was retrospectively analyzed.

    RESULTS: The authors successfully performed 113 nephron-sparing surgeries and 21 radical nephrectomies with a complication rate of 7.9%. During follow-up, 3 cases were classified according to surgical margin status because they lacked an intact tumor capsule. There was only 1 case of local recurrence, and there were no cases of metastasis. A high ROADS score was correlated with greater operative complexity, such as longer operation and ischemia times and higher estimated blood loss and complication rates. However, renal function and short-term oncologic outcomes were not related to the score.

    CONCLUSIONS: The ROADS scoring system provides a standardized, quantitative, 3-dimensional anatomic classification to guide surgical strategy in renal sinus tumors.

  15. Huang Q, Zhao G, Chen Y, Wu P, Li S, Peng C, et al.
    J Urol, 2023 Jan;209(1):99-110.
    PMID: 36194169 DOI: 10.1097/JU.0000000000002952
    PURPOSE: We introduce an intrapericardial control technique using a robotic approach in the surgical treatment of renal tumor with level IV inferior vena cava thrombus to decrease the severe complications associated with cardiopulmonary bypass and deep hypothermic circulatory arrest.

    MATERIALS AND METHODS: Eight patients with level IV inferior vena cava thrombi not extending into the atrium underwent transabdominal-transdiaphragmatic robot-assisted inferior vena cava thrombectomy obviating cardiopulmonary bypass/deep hypothermic circulatory arrest (cardiopulmonary bypass-free group) by an expert team comprising urological, hepatobiliary, and cardiovascular surgeons. The central diaphragm tendon and pericardium were transabdominally dissected until the intrapericardial inferior vena cava were exposed and looped proximal to the cranial end of the thrombi under intraoperative ultrasound guidance. As controls, 14 patients who underwent robot-assisted inferior vena cava thrombectomy with cardiopulmonary bypass (cardiopulmonary bypass group) and 25 patients who underwent open thrombectomy with cardiopulmonary bypass/deep hypothermic circulatory arrest (cardiopulmonary bypass/deep hypothermic circulatory arrest group) were included. Clinicopathological, operative, and survival outcomes were retrospectively analyzed.

    RESULTS: Eight robot-assisted inferior vena cava thrombectomies were successfully performed without cardiopulmonary bypass, with 1 open conversion. The median operation time and first porta hepatis occlusion time were shorter, and estimated blood loss was lower in the cardiopulmonary bypass-free group as compared to the cardiopulmonary bypass group (540 vs 586.5 minutes, 16.5 vs 38.5. minutes, and 2,050 vs 3,500 mL, respectively). Severe complications (level IV-V) were also lower in the cardiopulmonary bypass-free group than in cardiopulmonary bypass and cardiopulmonary bypass/deep hypothermic circulatory arrest groups (25% vs 50% vs 40%). Oncologic outcomes were comparable among the 3 groups in short-term follow-up.

    CONCLUSIONS: Pure transabdominal-transdiaphragmatic robot-assisted inferior vena cava thrombectomy without cardiopulmonary bypass/deep hypothermic circulatory arrest represents as an alternative minimally invasive approach for selected level IV inferior vena cava thrombi.

  16. Shi T, Huang Q, Liu K, Du S, Fan Y, Yang L, et al.
    Eur Urol, 2020 10;78(4):592-602.
    PMID: 32305170 DOI: 10.1016/j.eururo.2020.03.020
    BACKGROUND: Robot-assisted thrombectomy (RAT) for inferior vena cava (IVC) thrombus (RAT-IVCT) is being increasingly reported. However, the techniques and indications for robot-assisted cavectomy (RAC) for IVC thrombus are not well described.

    OBJECTIVE: To develop a decision-making program and analyze multi-institutional outcomes of RAC-IVCT versus RAT-IVCT.

    DESIGN, SETTING, AND PARTICIPANTS: Ninety patients with renal cell carcinoma (RCC) with level II IVCT were included from eight Chinese urological centers, and underwent RAC-IVCT (30 patients) or RAT-IVCT (60 patients) from June 2013 to January 2019.

    SURGICAL PROCEDURE: The surgical strategy was based on IVCT imaging characteristics. RAT-IVCT was performed with standardized cavotomy, thrombectomy, and IVC reconstruction. RAC-IVCT was mainly performed in patients with extensive IVC wall invasion when the collateral blood vessels were well-established. For right-sided RCC, the IVC from the infrarenal vein to the infrahepatic veins was stapled. For left-sided RCC, the IVC from the suprarenal vein to the infrahepatic veins was removed and caudal IVC reconstruction was performed to ensure the right renal vein returned through the IVC collaterals.

    MEASUREMENTS: Clinicopathological, operative, and survival outcomes were collected and analyzed.

    RESULTS AND LIMITATIONS: All procedures were successfully performed without open conversion. The median operation time (268 vs 190 min) and estimated blood loss (1500 vs 400 ml) were significantly greater for RAC-IVCT versus RAT-IVCT (both p < 0.001). IVC invasion was a risk factor for progression-free and overall survival at midterm follow-up. Large-volume and long-term follow-up studies are needed.

    CONCLUSIONS: RAC-IVCT or RAT-IVCT represents an alternative minimally invasive approach for selected RCC patients with level II IVCT. Selection of RAC-IVCT or RAT-IVCT is mainly based on preoperative IVCT imaging characteristics, including the presence of IVC wall invasion, the affected kidney, and establishment of the collateral circulation.

    PATIENT SUMMARY: In this study we found that robotic surgeries for level II inferior vena cava thrombus were feasible and safe. Preoperative imaging played an important role in establishing an appropriate surgical plan.

  17. 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 4c hints at a larger distance on average with respect to the jet axis, reflecting a diffusion of charm quarks in the medium created in heavy ion collisions. At higher p_{T}^{D}, the Pb-Pb and pp radial distributions are found to be similar.
  18. 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.
  19. 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^{±}.
  20. 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.
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