Displaying publications 1 - 20 of 210 in total

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  1. Saw KY, Anz AW, Jee CS, Low SF, Dawam A, Ramlan A
    Orthop Surg, 2024 Feb;16(2):506-513.
    PMID: 38087402 DOI: 10.1111/os.13949
    BACKGROUND: Treatment of osteochondral defects (OCDs) of the knee joint remains challenging. The purpose of this study was to evaluate the clinical and radiological results of osteochondral regeneration following intra-articular injections of autologous peripheral blood stem cells (PBSC) plus hyaluronic acid (HA) after arthroscopic subchondral drilling into OCDs of the knee joint.

    CASE PRESENTATION: Five patients with OCDs of the knee joint are presented. The etiology includes osteochondritis dissecans, traumatic knee injuries, previously failed cartilage repair procedures involving microfractures and OATS (osteochondral allograft transfer systems). PBSC were harvested 1 week after surgery. Patients received intra-articular injections at week 1, 2, 3, 4, and 5 after surgery. Then at 6 months after surgery, intra-articular injections were administered at a weekly interval for 3 consecutive weeks. These 3 weekly injections were repeated at 12, 18 and 24 months after surgery. Each patient received a total of 17 injections. Subjective International Knee Documentation Committee (IKDC) scores and MRI scans were obtained preoperatively and postoperatively at serial visits. At follow-ups of >5 years, the mean preoperative and postoperative IKDC scores were 47.2 and 80.7 respectively (p = 0.005). IKDC scores for all patients exceeded the minimal clinically important difference values of 8.3, indicating clinical significance. Serial MRI scans charted the repair and regeneration of the OCDs with evidence of bone growth filling-in the base of the defects, followed by reformation of the subchondral bone plate and regeneration of the overlying articular cartilage.

    CONCLUSION: These case studies showed that this treatment is able to repair and regenerate both the osseous and articular cartilage components of knee OCDs.

  2. Saw KY, Anz AW, Ng RC, Jee CS, Low SF, Dorvault C, et al.
    Arthroscopy, 2021 08;37(8):2502-2517.
    PMID: 34265388 DOI: 10.1016/j.arthro.2021.01.067
    PURPOSE: The purpose of this study was to evaluate the safety and efficacy of intra-articular injections of autologous peripheral blood stem cells (PBSCs) plus hyaluronic acid (HA) after arthroscopic subchondral drilling into massive chondral defects of the knee joint and to determine whether PBSC therapy can improve functional outcome and reduce pain of the knee joint better than HA plus physiotherapy.

    METHODS: This is a dual-center randomized controlled trial (RCT). Sixty-nine patients aged 18 to 55 years with International Cartilage Repair Society grade 3 and 4 chondral lesions (size ≥3 cm2) of the knee joint were randomized equally into (1) a control group receiving intra-articular injections of HA plus physiotherapy and (2) an intervention group receiving arthroscopic subchondral drilling into chondral defects and postoperative intra-articular injections of PBSCs plus HA. The coprimary efficacy endpoints were subjective International Knee Documentation Committee (IKDC) and Knee Injury and Osteoarthritis Outcome Score (KOOS)-pain subdomain measured at month 24. The secondary efficacy endpoints included all other KOOS subdomains, Numeric Rating Scale (NRS), and Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART) scores.

    RESULTS: At 24 months, the mean IKDC scores for the control and intervention groups were 48.1 and 65.6, respectively (P < .0001). The mean for KOOS-pain subdomain scores were 59.0 (control) and 86.0 (intervention) with P < .0001. All other KOOS subdomain, NRS, and MOCART scores were statistically significant (P < .0001) at month 24. Moreover, for the intervention group, 70.8% of patients had IKDC and KOOS-pain subdomain scores exceeding the minimal clinically important difference values, indicating clinical significance. There were no notable adverse events that were unexpected and related to the study drug or procedures.

    CONCLUSIONS: Arthroscopic marrow stimulation with subchondral drilling into massive chondral defects of the knee joint followed by postoperative intra-articular injections of autologous PBSCs plus HA is safe and showed a significant improvement of clinical and radiologic scores compared with HA plus physiotherapy.

    LEVEL OF EVIDENCE: Level I, RCT.

  3. Anz AW, Torres J, Plummer HA, Siew-Yoke Jee C, Dekker TJ, Johnson KB, et al.
    Arthroscopy, 2021 11;37(11):3347-3356.
    PMID: 33940122 DOI: 10.1016/j.arthro.2021.04.036
    PURPOSE: The primary objective of this study was to reproduce and validate the harvest, processing and storage of peripheral blood stem cells for a subsequent cartilage repair trial, evaluating safety, reliability, and potential to produce viable, sterile stem cells.

    METHODS: Ten healthy subjects (aged 19-44 years) received 3 consecutive daily doses of filgrastim followed by an apheresis harvest of mononuclear cells on a fourth day. In a clean room, the apheresis product was prepared for cryopreservation and processed into 4 mL aliquots. Sterility and qualification testing were performed pre-processing and post-processing at multiple time points out to 2 years. Eight samples were shipped internationally to validate cell transport potential. One sample from all participants was cultured to test proliferative potential with colony forming unit (CFU) assay. Five samples, from 5 participants were tested for differentiation potential, including chondrogenic, adipogenic, osteogenic, endoderm, and ectoderm assays.

    RESULTS: Fresh aliquots contained an average of 532.9 ± 166. × 106 total viable cells/4 mL vial and 2.1 ± 1.0 × 106 CD34+ cells/4 mL vial. After processing for cryopreservation, the average cell count decreased to 331.3 ± 79. × 106 total viable cells /4 mL vial and 1.5 ± 0.7 × 106 CD34+ cells/4 mL vial CD34+ cells. Preprocessing viability averaged 99% and postprocessing 88%. Viability remained constant after cryopreservation at all subsequent time points. All sterility testing was negative. All samples showed proliferative potential, with average CFU count 301.4 ± 63.9. All samples were pluripotent.

    CONCLUSIONS: Peripheral blood stem cells are pluripotent and can be safely harvested/stored with filgrastim, apheresis, clean-room processing, and cryopreservation. These cells can be stored for 2 years and shipped without loss of viability.

    CLINICAL RELEVANCE: This method represents an accessible stem cell therapy in development to augment cartilage repair.

  4. Ng WH, Johnston EK, Tan JJ, Bliley JM, Feinberg AW, Stolz DB, et al.
    Elife, 2022 01 12;11.
    PMID: 35018887 DOI: 10.7554/eLife.67872
    The extensive crosstalk between the developing heart and lung is critical to their proper morphogenesis and maturation. However, there remains a lack of models that investigate the critical cardio-pulmonary mutual interaction during human embryogenesis. Here, we reported a novel stepwise strategy for directing the simultaneous induction of both mesoderm-derived cardiac and endoderm-derived lung epithelial lineages within a single differentiation of human-induced pluripotent stem cells (hiPSCs) via temporal specific tuning of WNT and nodal signaling in the absence of exogenous growth factors. Using 3D suspension culture, we established concentric cardio-pulmonary micro-Tissues (μTs), and expedited alveolar maturation in the presence of cardiac accompaniment. Upon withdrawal of WNT agonist, the cardiac and pulmonary components within each dual-lineage μT effectively segregated from each other with concurrent initiation of cardiac contraction. We expect that our multilineage differentiation model will offer an experimentally tractable system for investigating human cardio-pulmonary interaction and tissue boundary formation during embryogenesis.
  5. Colella JP, Agwanda BR, Anwarali Khan FA, Bates J, Carrión Bonilla CA, de la Sancha NU, et al.
    Science, 2020 11 13;370(6518):773-774.
    PMID: 33184198 DOI: 10.1126/science.abe4813
  6. Bartlett AW, Mohamed TJ, Sudjaritruk T, Kurniati N, Nallusamy R, Hansudewechakul R, et al.
    Pediatr Infect Dis J, 2019 03;38(3):287-292.
    PMID: 30281549 DOI: 10.1097/INF.0000000000002208
    BACKGROUND: Perinatally HIV-infected adolescents (PHIVA) are exposed to a chronic systemic infection and long-term antiretroviral therapy (ART), leaving them susceptible to morbidities associated with inflammation, immunodeficiency and drug toxicity.

    METHODS: Data collected 2001 to 2016 from PHIVA 10-19 years of age within a regional Asian cohort were analyzed using competing risk time-to-event and Poisson regression analyses to describe the nature and incidence of morbidity events and hospitalizations and identify factors associated with disease-related, treatment-related and overall morbidity. Morbidity was defined according to World Health Organization clinical staging criteria and U.S. National Institutes of Health Division of AIDS criteria.

    RESULTS: A total 3,448 PHIVA contributed 17,778 person-years. Median age at HIV diagnosis was 5.5 years, and ART initiation was 6.9 years. There were 2,562 morbidity events and 307 hospitalizations. Cumulative incidence for any morbidity was 51.7%, and hospitalization was 10.0%. Early adolescence was dominated by disease-related infectious morbidity, with a trend toward noninfectious and treatment-related morbidity in later adolescence. Higher overall morbidity rates were associated with a CD4 count <350 cells/µL, HIV viral load ≥10,000 copies/mL and experiencing prior morbidity at age <10 years. Lower overall morbidity rates were found for those 15-19 years of age compared with 10-14 years and those who initiated ART at age 5-9 years compared with <5 or ≥10 years.

    CONCLUSIONS: Half of our PHIVA cohort experienced a morbidity event, with a trend from disease-related infectious events to treatment-related and noninfectious events as PHIVA age. ART initiation to prevent immune system damage, optimize virologic control and minimize childhood morbidity are key to limiting adolescent morbidity.

  7. Thompson CW, Phelps KL, Allard MW, Cook JA, Dunnum JL, Ferguson AW, et al.
    mBio, 2021 01 12;12(1).
    PMID: 33436435 DOI: 10.1128/mBio.02698-20
    Despite being nearly 10 months into the COVID-19 (coronavirus disease 2019) pandemic, the definitive animal host for SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2), the causal agent of COVID-19, remains unknown. Unfortunately, similar problems exist for other betacoronaviruses, and no vouchered specimens exist to corroborate host species identification for most of these pathogens. This most basic information is critical to the full understanding and mitigation of emerging zoonotic diseases. To overcome this hurdle, we recommend that host-pathogen researchers adopt vouchering practices and collaborate with natural history collections to permanently archive microbiological samples and host specimens. Vouchered specimens and associated samples provide both repeatability and extension to host-pathogen studies, and using them mobilizes a large workforce (i.e., biodiversity scientists) to assist in pandemic preparedness. We review several well-known examples that successfully integrate host-pathogen research with natural history collections (e.g., yellow fever, hantaviruses, helminths). However, vouchering remains an underutilized practice in such studies. Using an online survey, we assessed vouchering practices used by microbiologists (e.g., bacteriologists, parasitologists, virologists) in host-pathogen research. A much greater number of respondents permanently archive microbiological samples than archive host specimens, and less than half of respondents voucher host specimens from which microbiological samples were lethally collected. To foster collaborations between microbiologists and natural history collections, we provide recommendations for integrating vouchering techniques and archiving of microbiological samples into host-pathogen studies. This integrative approach exemplifies the premise underlying One Health initiatives, providing critical infrastructure for addressing related issues ranging from public health to global climate change and the biodiversity crisis.
  8. Bartlett AW, Truong KH, Songtaweesin WN, Chokephaibulkit K, Hansudewechakul R, Ly PS, et al.
    AIDS, 2018 07 31;32(12):1689-1697.
    PMID: 29794827 DOI: 10.1097/QAD.0000000000001883
    OBJECTIVES: The aim of this study was to describe characteristics of perinatally HIV-infected adolescents (PHIVAs), factors associated with mortality, and outcomes at transition.

    DESIGN: Ongoing observational database collating clinical data on HIV-infected children and adolescents in Asia.

    METHODS: Data from 2001 to 2016 relating to adolescents (10-19 years) with perinatal HIV infection were analysed to describe characteristics at adolescent entry and transition and combination antiretroviral therapy (cART) regimens across adolescence. A competing risk regression analysis was used to determine characteristics at adolescent entry associated with mortality. Outcomes at transition were compared on the basis of age at cART initiation.

    RESULTS: Of 3448 PHIVA, 644 had reached transition. Median age at HIV diagnosis was 5.5 years, cART initiation 7.2 years and transition 17.9 years. At adolescent entry, 35.0% had CD4+ cell count less than 500 cells/μl and 51.1% had experienced a WHO stage III/IV clinical event. At transition, 38.9% had CD4+ cell count less than 500 copies/ml, and 53.4% had experienced a WHO stage III/IV clinical event. Mortality rate was 0.71 per 100 person-years, with HIV RNA ≥1000 copies/ml, CD4+ cell count less than 500 cells/μl, height-for-age or weight-for-age z-score less than -2, history of a WHO stage III/IV clinical event or hospitalization and at least second cART associated with mortality. For transitioning PHIVA, those who commenced cART age less than 5 years had better virologic and immunologic outcomes, though were more likely to be on at least second cART.

    CONCLUSION: Delayed HIV diagnosis and cART initiation resulted in considerable morbidity and poor immune status by adolescent entry. Durable first-line cART regimens to optimize disease control are key to minimizing mortality. Early cART initiation provides the best virologic and immunologic outcomes at transition.

  9. Bartlett AW, Sudjaritruk T, Mohamed TJ, Anugulruengkit S, Kumarasamy N, Phongsamart W, et al.
    Clin Infect Dis, 2021 Oct 05;73(7):e1919-e1926.
    PMID: 32589711 DOI: 10.1093/cid/ciaa872
    BACKGROUND: Combination antiretroviral therapy (cART) failure is a major threat to human immunodeficiency virus (HIV) programs, with implications for individual- and population-level outcomes. Adolescents with perinatally acquired HIV infection (PHIVA) should be a focus for treatment failure given their poorer outcomes compared to children and adults.

    METHODS: Data (2014-2018) from a regional cohort of Asian PHIVA who received at least 6 months of continuous cART were analyzed. Treatment failure was defined according to World Health Organization criteria. Descriptive analyses were used to report treatment failure and subsequent management and evaluate postfailure CD4 count and viral load trends. Kaplan-Meier survival analyses were used to compare the cumulative incidence of death and loss to follow-up (LTFU) by treatment failure status.

    RESULTS: A total 3196 PHIVA were included in the analysis with a median follow-up period of 3.0 years, of whom 230 (7.2%) had experienced 292 treatment failure events (161 virologic, 128 immunologic, 11 clinical) at a rate of 3.78 per 100 person-years. Of the 292 treatment failure events, 31 (10.6%) had a subsequent cART switch within 6 months, which resulted in better immunologic and virologic outcomes compared to those who did not switch cART. The 5-year cumulative incidence of death and LTFU following treatment failure was 18.5% compared to 10.1% without treatment failure.

    CONCLUSIONS: Improved implementation of virologic monitoring is required to realize the benefits of virologic determination of cART failure. There is a need to address issues related to accessibility to subsequent cART regimens, poor adherence limiting scope to switch regimens, and the role of antiretroviral resistance testing.

  10. Bradbury K, Steele M, Corbett T, Geraghty AWA, Krusche A, Heber E, et al.
    NPJ Digit Med, 2019;2:85.
    PMID: 31508496 DOI: 10.1038/s41746-019-0163-4
    This paper illustrates a rigorous approach to developing digital interventions using an evidence-, theory- and person-based approach. Intervention planning included a rapid scoping review that identified cancer survivors' needs, including barriers and facilitators to intervention success. Review evidence (N = 49 papers) informed the intervention's Guiding Principles, theory-based behavioural analysis and logic model. The intervention was optimised based on feedback on a prototype intervention through interviews (N = 96) with cancer survivors and focus groups with NHS staff and cancer charity workers (N = 31). Interviews with cancer survivors highlighted barriers to engagement, such as concerns about physical activity worsening fatigue. Focus groups highlighted concerns about support appointment length and how to support distressed participants. Feedback informed intervention modifications, to maximise acceptability, feasibility and likelihood of behaviour change. Our systematic method for understanding user views enabled us to anticipate and address important barriers to engagement. This methodology may be useful to others developing digital interventions.
  11. Mu W, Bartlett AW, Bunupuradah T, Chokephaibulkit K, Kumarasamy N, Ly PS, et al.
    J Acquir Immune Defic Syndr, 2019 03 01;80(3):308-315.
    PMID: 30531299 DOI: 10.1097/QAI.0000000000001921
    BACKGROUND: Virologic failure is a major threat to maintaining effective combination antiretroviral therapy, especially for children in need of lifelong treatment. With efforts to expand access to HIV viral load testing, our understanding of pediatric virologic failure is evolving.

    SETTING: An Asian cohort in 16 pediatric HIV services across 6 countries.

    METHODS: From 2005 to 2014, patients younger than 20 years who achieved virologic suppression and had subsequent viral load testing were included. Early virologic failure was defined as a HIV RNA ≥1000 copies per milliliter within 12 months of virologic suppression, and late virologic as a HIV RNA ≥1000 copies per milliliter after 12 months following virologic suppression. Characteristics at combination antiretroviral therapy initiation and virologic suppression were described, and a competing risk time-to-event analysis was used to determine cumulative incidence of virologic failure and factors at virologic suppression associated with early and late virologic failure.

    RESULTS: Of 1105 included in the analysis, 182 (17.9%) experienced virologic failure. The median age at virologic suppression was 6.9 years, and the median time to virologic failure was 24.6 months after virologic suppression. The incidence rate for a first virologic failure event was 3.3 per 100 person-years. Factors at virologic suppression associated with late virologic failure included older age, mostly rural clinic setting, tuberculosis, protease inhibitor-based regimens, and early virologic failure. No risk factors were identified for early virologic failure.

    CONCLUSIONS: Around 1 in 5 experienced virologic failure in our cohort after achieving virologic suppression. Targeted interventions to manage complex treatment scenarios, including adolescents, tuberculosis coinfection, and those with poor virologic control are required.

  12. Bartlett AW, Lumbiganon P, Kurniati N, Sudjaritruk T, Mohamed TJ, Hansudewechakul R, et al.
    J Adolesc Health, 2019 11;65(5):651-659.
    PMID: 31395514 DOI: 10.1016/j.jadohealth.2019.05.025
    PURPOSE: Antiretroviral monotherapy and treatment interruption are potential strategies for perinatally HIV-infected adolescents (PHIVA) who face challenges maintaining effective combination antiretroviral therapy (ART). We assessed the use and outcomes for adolescents receiving monotherapy or undergoing treatment interruption in a regional Asian cohort.

    METHODS: Regional Asian data (2001-2016) were analyzed to describe PHIVA who experienced ≥2 weeks of lamivudine or emtricitabine monotherapy or treatment interruption and trends in CD4 count and HIV viral load during and after episodes. Survival analyses were used for World Health Organization (WHO) stage III/IV clinical and immunologic event-free survival during monotherapy or treatment interruption, and a Poisson regression to determine factors associated with monotherapy or treatment interruption.

    RESULTS: Of 3,448 PHIVA, 84 (2.4%) experienced 94 monotherapy episodes, and 147 (4.3%) experienced 174 treatment interruptions. Monotherapy was associated with older age, HIV RNA >400 copies/mL, younger age at ART initiation, and exposure to ≥2 combination ART regimens. Treatment interruption was associated with CD4 count <350 cells/μL, HIV RNA ≥1,000 copies/mL, ART adverse event, and commencing ART age ≥10 years compared with age <3 years. WHO clinical stage III/IV 1-year event-free survival was 96% and 85% for monotherapy and treatment interruption cohorts, respectively. WHO immunologic stage III/IV 1-year event-free survival was 52% for both cohorts. Those who experienced monotherapy or treatment interruption for more than 6 months had worse immunologic and virologic outcomes.

    CONCLUSIONS: Until challenges of treatment adherence, engagement in care, and combination ART durability/tolerability are met, monotherapy and treatment interruption will lead to poor long-term outcomes.

  13. Bartlett AW, Lumbiganon P, Jamal Mohamed TA, Lapphra K, Muktiarti D, Du QT, et al.
    J Acquir Immune Defic Syndr, 2019 12 15;82(5):431-438.
    PMID: 31714422 DOI: 10.1097/QAI.0000000000002184
    BACKGROUND: Perinatally HIV-infected adolescents (PHIVA) are an expanding population vulnerable to loss to follow-up (LTFU). Understanding the epidemiology and factors for LTFU is complicated by varying LTFU definitions.

    SETTING: Asian regional cohort incorporating 16 pediatric HIV services across 6 countries.

    METHODS: Data from PHIVA (aged 10-19 years) who received combination antiretroviral therapy 2007-2016 were used to analyze LTFU through (1) an International epidemiology Databases to Evaluate AIDS (IeDEA) method that determined LTFU as >90 days late for an estimated next scheduled appointment without returning to care and (2) the absence of patient-level data for >365 days before the last data transfer from clinic sites. Descriptive analyses and competing-risk survival and regression analyses were used to evaluate LTFU epidemiology and associated factors when analyzed using each method.

    RESULTS: Of 3509 included PHIVA, 275 (7.8%) met IeDEA and 149 (4.3%) met 365-day absence LTFU criteria. Cumulative incidence of LTFU was 19.9% and 11.8% using IeDEA and 365-day absence criteria, respectively. Risk factors for LTFU across both criteria included the following: age at combination antiretroviral therapy initiation <5 years compared with age ≥5 years, rural clinic settings compared with urban clinic settings, and high viral loads compared with undetectable viral loads. Age 10-14 years compared with age 15-19 years was another risk factor identified using 365-day absence criteria but not IeDEA LTFU criteria.

    CONCLUSIONS: Between 12% and 20% of PHIVA were determined LTFU with treatment fatigue and rural treatment settings consistent risk factors. Better tracking of adolescents is required to provide a definitive understanding of LTFU and optimize evidence-based models of care.

  14. Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Bergauer T, Dragicevic M, et al.
    Phys Rev Lett, 2015 Feb 13;114(6):061801.
    PMID: 25723204
    A search for new long-lived particles decaying to leptons is presented using proton-proton collisions produced by the LHC at √[s]=8  TeV. Data used for the analysis were collected by the CMS detector and correspond to an integrated luminosity of 19.7  fb(-1). Events are selected with an electron and muon with opposite charges that both have transverse impact parameter values between 0.02 and 2 cm. The search has been designed to be sensitive to a wide range of models with nonprompt e-μ final states. Limits are set on the "displaced supersymmetry" model, with pair production of top squarks decaying into an e-μ final state via R-parity-violating interactions. The results are the most restrictive to date on this model, with the most stringent limit being obtained for a top squark lifetime corresponding to cτ=2  cm, excluding masses below 790 GeV at 95% confidence level.
  15. Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Bergauer T, Dragicevic M, et al.
    Phys Rev Lett, 2015 Feb 6;114(5):051801.
    PMID: 25699433
    A study of vector boson scattering in pp collisions at a center-of-mass energy of 8 TeV is presented. The data sample corresponds to an integrated luminosity of 19.4  fb(-1) collected with the CMS detector. Candidate events are selected with exactly two leptons of the same charge, two jets with large rapidity separation and high dijet mass, and moderate missing transverse energy. The signal region is expected to be dominated by electroweak same-sign W-boson pair production. The observation agrees with the standard model prediction. The observed significance is 2.0 standard deviations, where a significance of 3.1 standard deviations is expected based on the standard model. Cross section measurements for W(±)W(±) and WZ processes in the fiducial region are reported. Bounds on the structure of quartic vector-boson interactions are given in the framework of dimension-eight effective field theory operators, as well as limits on the production of doubly charged Higgs bosons.
  16. Chatrchyan S, Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Bergauer T, et al.
    Phys Rev Lett, 2014 Apr 25;112(16):161802.
    PMID: 24815637
    Results are presented of a search for a "natural" supersymmetry scenario with gauge mediated symmetry breaking. It is assumed that only the supersymmetric partners of the top quark (the top squark) and the Higgs boson (Higgsino) are accessible. Events are examined in which there are two photons forming a Higgs boson candidate, and at least two b-quark jets. In 19.7  fb-1 of proton-proton collision data at s=8  TeV, recorded in the CMS experiment, no evidence of a signal is found and lower limits at the 95% confidence level are set, excluding the top squark mass below 360 to 410 GeV, depending on the Higgsino mass.
  17. CMS Collaboration, Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Bergauer T, et al.
    Eur Phys J C Part Fields, 2014 09 26;74(9):3036.
    PMID: 25814912
    Searches for the direct electroweak production of supersymmetric charginos, neutralinos, and sleptons in a variety of signatures with leptons and [Formula: see text], [Formula: see text], and Higgs bosons are presented. Results are based on a sample of proton-proton collision data collected at center-of-mass energy [Formula: see text] with the CMS detector in 2012, corresponding to an integrated luminosity of 19.5 [Formula: see text]. The observed event rates are in agreement with expectations from the standard model. These results probe charginos and neutralinos with masses up to 720 [Formula: see text], and sleptons up to 260 [Formula: see text], depending on the model details.
  18. Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Bergauer T, Dragicevic M, et al.
    Eur Phys J C Part Fields, 2014 10 15;74(10):3076.
    PMID: 25814871
    Observation of the diphoton decay mode of the recently discovered Higgs boson and measurement of some of its properties are reported. The analysis uses the entire dataset collected by the CMS experiment in proton-proton collisions during the 2011 and 2012 LHC running periods. The data samples correspond to integrated luminosities of 5.1[Formula: see text]at [Formula: see text] and 19.7[Formula: see text]at 8[Formula: see text] . A clear signal is observed in the diphoton channel at a mass close to 125[Formula: see text] with a local significance of [Formula: see text], where a significance of [Formula: see text] is expected for the standard model Higgs boson. The mass is measured to be [Formula: see text] , and the best-fit signal strength relative to the standard model prediction is [Formula: see text][Formula: see text][Formula: see text]. Additional measurements include the signal strength modifiers associated with different production mechanisms, and hypothesis tests between spin-0 and spin-2 models.
  19. Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Asilar E, Bergauer T, et al.
    Phys Rev Lett, 2016 Feb 19;116(7):071801.
    PMID: 26943527 DOI: 10.1103/PhysRevLett.116.071801
    A search for narrow resonances in proton-proton collisions at sqrt[s]=13  TeV is presented. The invariant mass distribution of the two leading jets is measured with the CMS detector using a data set corresponding to an integrated luminosity of 2.4  fb^{-1}. The highest observed dijet mass is 6.1 TeV. The distribution is smooth and no evidence for resonant particles is observed. Upper limits at 95% confidence level are set on the production cross section for narrow resonances with masses above 1.5 TeV. When interpreted in the context of specific models, the limits exclude string resonances with masses below 7.0 TeV, scalar diquarks below 6.0 TeV, axigluons and colorons below 5.1 TeV, excited quarks below 5.0 TeV, color-octet scalars below 3.1 TeV, and W^{'} bosons below 2.6 TeV. These results significantly extend previously published limits.
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