Displaying publications 1 - 20 of 217 in total

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  1. Fulltext Dietary inadequacy in Tanzania is linked to the rising cost of nutritious foods and consumption of food-away-from-home
    Ignowski L, Belton B, Tran N, Ameye H
    Glob Food Sec, 2023 Jun;37:100679.
    PMID: 37351553 DOI: 10.1016/j.gfs.2023.100679
    This study contributes to the growing literature on dietary quality and accessibility in the Global South. We analyze the nutrition implications of changing dietary patterns between 2008 and 2019 in one of Africa's largest and fastest growing economies, Tanzania, and compare patterns at national and sub-national scales. We find that: (1) Rising incomes have not been associated with marked increases in the diversity of food consumed at home; (2) Consumption of food away from home has increased dramatically; (3) Most food consumed in Tanzanian homes is purchased instead of self-produced; (4) There have not been clear improvements in the adequacy of micronutrient consumption obtained from food eaten at home; (5) The most affordable sources of key micronutrients, including nutrient dense foods such as dried fish, have become more expensive. Our findings indicate that in Tanzania the amount and diversity of nutritious foods eaten at home have not improved with rising incomes, but consumption of energy-dense processed foods eaten away from home has increased rapidly, likely reflecting differences in convenience and relative prices. To improve Tanzanian diets in coming years, coordinated nutrition-sensitive policy actions will be required on both the supply- and demand-sides.
  2. Sustainable aquaculture development in sub-Saharan Africa
    Ragasa C, Charo-Karisa H, Rurangwa E, Tran N, Shikuku KM
    Nat Food, 2022 Feb;3(2):92-94.
    PMID: 37117967 DOI: 10.1038/s43016-022-00467-1
  3. Fulltext Experimental and survey-based data on willingness to pay for seafood safety and environmental sustainability certification in Nigeria
    Shikuku KM, Tran N, Pincus L, Hoffmann V, Lagerkvist CJ, Akintola SL, et al.
    Data Brief, 2020 Jun;30:105540.
    PMID: 32346573 DOI: 10.1016/j.dib.2020.105540
    Aquatic foods, including fish, are a substantial component of animal source foods globally, and make a critical nutritional contribution to diets in many contexts. In the global North, concern among consumers and regulators over the safety and environmental sustainability of seafood, particularly in developed nations, has led to the development of increasingly stringent seafood safety standards. While such standards may constitute regularity, logistical, and economic barriers to participation in export markets by small-scale producers, they have in other contexts catalysed upgrades to production and post-harvest handling practices within value chains associated with both capture fisheries and aquaculture. The health burden of foodborne illnesses is a major concern in developing countries. As incomes rise, consumers in developing countries are increasingly willing to pay a premium for safer and environmentally sustainable foods. However, there is little empirical evidence on consumers' willingness to pay for seafood safety in developing countries, particularly in sub-Saharan Africa. Data on demand for seafood safety and environmental sustainability certification in African countries are largely unavailable in the public domain. In this paper, we describe data collected in Lagos State, Nigeria in October and November 2019. Experiments in the form of Becker-DeGroote-Marschak (BDM) auction mechanism, and post experiment surveys were conducted with 200 fish consumers in fish markets. These data can be used to assess whether consumers' demand for safe and healthy seafood from local markets can be harnessed to generate positive economic returns to producers.
  4. Fulltext The future of fish in Africa: Employment and investment opportunities
    Chan CY, Tran N, Cheong KC, Sulser TB, Cohen PJ, Wiebe K, et al.
    PLoS One, 2021;16(12):e0261615.
    PMID: 34936682 DOI: 10.1371/journal.pone.0261615
    One of the most pressing challenges facing food systems in Africa is ensuring availability of a healthy and sustainable diet to 2.4 billion people by 2050. The continent has struggled with development challenges, particularly chronic food insecurity and pervasive poverty. In Africa's food systems, fish and other aquatic foods play a multifaceted role in generating income, and providing a critical source of essential micronutrients. To date, there are no estimates of investment and potential returns for domestic fish production in Africa. To contribute to policy debates about the future of fish in Africa, we applied the International Model for Policy Analysis of Agriculture Commodities and Trade (IMPACT) to explore two Pan-African scenarios for fish sector growth: a business-as-usual (BAU) scenario and a high-growth scenario for capture fisheries and aquaculture with accompanying strong gross domestic product growth (HIGH). Post-model analysis was used to estimate employment and aquaculture investment requirements for the sector in Africa. Africa's fish sector is estimated to support 20.7 million jobs in 2030, and 21.6 million by 2050 under the BAU. Approximately 2.6 people will be employed indirectly along fisheries and aquaculture value chains for every person directly employed in the fish production stage. Under the HIGH scenario, total employment in Africa's fish food system will reach 58.0 million jobs, representing 2.4% of total projected population in Africa by 2050. Aquaculture production value is estimated to achieve US$ 3.3 billion and US$ 20.4 billion per year under the BAU and HIGH scenarios by 2050, respectively. Farm-gate investment costs for the three key inputs (fish feeds, farm labor, and fish seed) to achieve the aquaculture volumes projected by 2050 are estimated at US$ 1.8 billion per year under the BAU and US$ 11.6 billion per year under the HIGH scenario. Sustained investments are critical to sustain capture fisheries and support aquaculture growth for food system transformation towards healthier diets.
  5. Three Decades of Dengue Surveillance in Five Highly Endemic South East Asian Countries
    Wartel TA, Prayitno A, Hadinegoro SR, Capeding MR, Thisyakorn U, Tran NH, et al.
    Asia Pac J Public Health, 2017 Jan;29(1):7-16.
    PMID: 28198645 DOI: 10.1177/1010539516675701
    We described and quantified epidemiologic trends in dengue disease burden in 5 Asian countries (Indonesia, Thailand, Malaysia, Philippines, and Vietnam) and identified and estimated outbreaks impact over the last 3 decades. Dengue surveillance data from 1980 to 2010 were retrieved from DengueNet and from World Health Organization sources. Trends in incidence, mortality, and case fatality rate (CFR) were systematically analyzed using annual average percent change (AAPC), and the contribution of epidemic years identified over the observation period was quantified. Over the 30-year period, incidence increased in all countries (AAPC 1980-2010: 6.7% in Thailand, 10.4% in Vietnam, 12.0% in Indonesia, 18.1% in Malaysia, 24.4% in Philippines). Mortality also increased in Indonesia, Malaysia, and Philippines (AAPC: 6.8%, 7.0%, and 29.2%, respectively), but slightly decreased in Thailand and Vietnam (AAPC: -1.3% and -2.5%), and CFR decreased in all countries (AAPC: -4.2% to -8.3%). Epidemic years, despite representing less than a third of the observation period, contributed from 1 to 3 times more cases versus nonepidemic years. Implementation of more sensitive surveillance methods over the study period may have contributed to a reporting or ascertainment bias in some countries. Nonetheless, these data support the urgent need for novel, integrated, or otherwise effective dengue prevention and control tools and approaches.
  6. Fulltext Dengue and other common causes of acute febrile illness in Asia: an active surveillance study in children
    Capeding MR, Chua MN, Hadinegoro SR, Hussain II, Nallusamy R, Pitisuttithum P, et al.
    PLoS Negl Trop Dis, 2013;7(7):e2331.
    PMID: 23936565 DOI: 10.1371/journal.pntd.0002331
    Common causes of acute febrile illness in tropical countries have similar symptoms, which often mimic those of dengue. Accurate clinical diagnosis can be difficult without laboratory confirmation and disease burden is generally under-reported. Accurate, population-based, laboratory-confirmed incidence data on dengue and other causes of acute fever in dengue-endemic Asian countries are needed.
  7. Fulltext Early diagnostic indicators of dengue versus other febrile illnesses in Asia and Latin America (IDAMS study): a multicentre, prospective, observational study
    Rosenberger KD, Phung Khanh L, Tobian F, Chanpheaktra N, Kumar V, Lum LCS, et al.
    Lancet Glob Health, 2023 Mar;11(3):e361-e372.
    PMID: 36796983 DOI: 10.1016/S2214-109X(22)00514-9
    BACKGROUND: Improvements in the early diagnosis of dengue are urgently needed, especially in resource-limited settings where the distinction between dengue and other febrile illnesses is crucial for patient management.

    METHODS: In this prospective, observational study (IDAMS), we included patients aged 5 years and older with undifferentiated fever at presentation from 26 outpatient facilities in eight countries (Bangladesh, Brazil, Cambodia, El Salvador, Indonesia, Malaysia, Venezuela, and Viet Nam). We used multivariable logistic regression to investigate the association between clinical symptoms and laboratory tests with dengue versus other febrile illnesses between day 2 and day 5 after onset of fever (ie, illness days). We built a set of candidate regression models including clinical and laboratory variables to reflect the need of a comprehensive versus parsimonious approach. We assessed performance of these models via standard measures of diagnostic values.

    FINDINGS: Between Oct 18, 2011, and Aug 4, 2016, we recruited 7428 patients, of whom 2694 (36%) were diagnosed with laboratory-confirmed dengue and 2495 (34%) with (non-dengue) other febrile illnesses and met inclusion criteria, and were included in the analysis. 2703 (52%) of 5189 included patients were younger than 15 years, 2486 (48%) were aged 15 years or older, 2179 (42%) were female and 3010 (58%) were male. Platelet count, white blood cell count, and the change in these variables from the previous day of illness had a strong association with dengue. Cough and rhinitis had strong associations with other febrile illnesses, whereas bleeding, anorexia, and skin flush were generally associated with dengue. Model performance increased between day 2 and 5 of illness. The comprehensive model (18 clinical and laboratory predictors) had sensitivities of 0·80 to 0·87 and specificities of 0·80 to 0·91, whereas the parsimonious model (eight clinical and laboratory predictors) had sensitivities of 0·80 to 0·88 and specificities of 0·81 to 0·89. A model that includes laboratory markers that are easy to measure (eg, platelet count or white blood cell count) outperformed the models based on clinical variables only.

    INTERPRETATION: Our results confirm the important role of platelet and white blood cell counts in diagnosing dengue, and the importance of serial measurements over subsequent days. We successfully quantified the performance of clinical and laboratory markers covering the early period of dengue. Resulting algorithms performed better than published schemes for distinction of dengue from other febrile illnesses, and take into account the dynamic changes over time. Our results provide crucial information needed for the update of guidelines, including the Integrated Management of Childhood Illness handbook.

    FUNDING: EU's Seventh Framework Programme.

    TRANSLATIONS: For the Bangla, Bahasa Indonesia, Portuguese, Khmer, Spanish and Vietnamese translations of the abstract see Supplementary Materials section.

  8. Fulltext Improving early prediction for adverse dengue outcomes using data from the IDAMS prospective multicentre study
    Phung Khanh L, Rosenberger KD, Dong Thi Hoai T, Nguyen Tan Thanh K, Tran Van N, Nguyen Tran N, et al.
    Nat Commun, 2026 Aug 21;17(1).
    PMID: 42764339 DOI: 10.1038/s41467-026-76450-2
    Early identification of individuals at risk of complications is important to improve dengue case-management and promote appropriate use of limited resources in high burden settings. In this prospective observational cohort, 7428 febrile outpatients were enrolled across 8 countries in Asia and Latin America and followed daily; 2230 individuals with confirmed dengue were included in the analysis, among whom 304 (14%) progressed to moderate/severe dengue and 38 (2%) to severe dengue during follow-up. We demonstrate evolving relationships between common clinical features, WHO clinical warning signs, and simple haematological parameters, with progression. Key predictors of moderate/severe dengue include low lymphocyte percentage, low total white blood cell count, low platelet count, and persistent vomiting and significant abdominal pain/tenderness. Multivariable models incorporating these variables predict the risk of moderate/severe dengue, initially with modest performance (AUC ~ 0.68), but improving subsequently as new daily data is included into the predictions (AUC ~ 0.73-0.85). We also demonstrate that using these models in combination with clinical decision-making pathways could facilitate earlier admission of high-risk patients without markedly increasing admissions of uncomplicated cases. These results should prove instrumental for updating guidelines on dengue triage and management, potentially providing major public health benefits in resource poor settings.
  9. Fulltext Searches for pair production of third-generation squarks in [Formula: see text][Formula: see text] pp collisions
    Sirunyan AM, Tumasyan A, Adam W, Asilar E, Bergauer T, Brandstetter J, et al.
    Eur Phys J C Part Fields, 2017;77(5):327.
    PMID: 28943785 DOI: 10.1140/epjc/s10052-017-4853-2
    Searches are presented for direct production of top or bottom squark pairs in proton-proton collisions at the CERN LHC. Two searches, based on complementary techniques, are performed in all-jet final states that are characterized by a significant imbalance in transverse momentum. An additional search requires the presence of a charged lepton isolated from other activity in the event. The data were collected in 2015 at a centre-of-mass energy of 13[Formula: see text] with the CMS detector and correspond to an integrated luminosity of 2.3[Formula: see text]. No statistically significant excess of events is found beyond the expected contribution from standard model processes. Exclusion limits are set in the context of simplified models of top or bottom squark pair production. Models with top and bottom squark masses up to 830 and 890[Formula: see text], respectively, are probed for light neutralinos. For models with top squark masses of 675[Formula: see text], neutralino masses up to 260[Formula: see text] are excluded at 95% confidence level.
  10. Study of Jet Quenching with Z+jet Correlations in Pb-Pb and pp Collisions at sqrt[s]_{NN}=5.02  TeV
    Sirunyan AM, Tumasyan A, Adam W, Asilar E, Bergauer T, Brandstetter J, et al.
    Phys Rev Lett, 2017 Aug 25;119(8):082301.
    PMID: 28952777 DOI: 10.1103/PhysRevLett.119.082301
    The production of jets in association with Z bosons, reconstructed via the μ^{+}μ^{-} and e^{+}e^{-} decay channels, is studied in pp and, for the first time, in Pb-Pb collisions. Both data samples were collected by the CMS experiment at the LHC, at a nucleon-nucleon center-of-mass energy of 5.02 TeV. The Pb-Pb collisions were analyzed in the 0%-30% centrality range. The back-to-back azimuthal alignment was studied in both pp and Pb-Pb collisions for Z bosons with transverse momentum p_{T}^{Z}>60  GeV/c and a recoiling jet with p_{T}^{jet}>30  GeV/c. The p_{T} imbalance x_{jZ}=p_{T}^{jet}/p_{T}^{Z}, as well as the average number of jet partners per Z, R_{jZ}, was studied in intervals of p_{T}^{Z}. The R_{jZ} is found to be smaller in Pb-Pb than in pp collisions, which suggests that in Pb-Pb collisions a larger fraction of partons associated with the Z bosons fall below the 30  GeV/c p_{T}^{jet} threshold because they lose energy.
  11. Fulltext Measurement of double-differential cross sections for top quark pair production in pp collisions at [Formula: see text][Formula: see text] and impact on parton distribution functions
    Sirunyan AM, Tumasyan A, Adam W, Asilar E, Bergauer T, Brandstetter J, et al.
    Eur Phys J C Part Fields, 2017;77(7):459.
    PMID: 28943791 DOI: 10.1140/epjc/s10052-017-4984-5
    Normalized double-differential cross sections for top quark pair ([Formula: see text]) production are measured in pp collisions at a centre-of-mass energy of 8[Formula: see text] with the CMS experiment at the LHC. The analyzed data correspond to an integrated luminosity of 19.7[Formula: see text]. The measurement is performed in the dilepton [Formula: see text] final state. The [Formula: see text] cross section is determined as a function of various pairs of observables characterizing the kinematics of the top quark and [Formula: see text] system. The data are compared to calculations using perturbative quantum chromodynamics at next-to-leading and approximate next-to-next-to-leading orders. They are also compared to predictions of Monte Carlo event generators that complement fixed-order computations with parton showers, hadronization, and multiple-parton interactions. Overall agreement is observed with the predictions, which is improved when the latest global sets of proton parton distribution functions are used. The inclusion of the measured [Formula: see text] cross sections in a fit of parametrized parton distribution functions is shown to have significant impact on the gluon distribution.
  12. Fulltext Measurement of the jet mass in highly boosted [Formula: see text] events from pp collisions at [Formula: see text][Formula: see text]
    Sirunyan AM, Tumasyan A, Adam W, Asilar E, Bergauer T, Brandstetter J, et al.
    Eur Phys J C Part Fields, 2017;77(7):467.
    PMID: 28943793 DOI: 10.1140/epjc/s10052-017-5030-3
    The first measurement of the jet mass [Formula: see text] of top quark jets produced in [Formula: see text] events from pp collisions at [Formula: see text] [Formula: see text] is reported for the jet with the largest transverse momentum [Formula: see text] in highly boosted hadronic top quark decays. The data sample, collected with the CMS detector, corresponds to an integrated luminosity of 19.7[Formula: see text]. The measurement is performed in the lepton+jets channel in which the products of the semileptonic decay [Formula: see text] with [Formula: see text] where [Formula: see text] is an electron or muon, are used to select [Formula: see text] events with large Lorentz boosts. The products of the fully hadronic decay [Formula: see text] with [Formula: see text] are reconstructed using a single Cambridge-Aachen jet with distance parameter [Formula: see text], and [Formula: see text] [Formula: see text]. The [Formula: see text] cross section as a function of [Formula: see text] is unfolded at the particle level and is used to test the modelling of highly boosted top quark production. The peak position of the [Formula: see text] distribution is sensitive to the top quark mass [Formula: see text], and the data are used to extract a value of [Formula: see text] to assess this sensitivity.
  13. Fulltext Measurement of the top quark mass using single top quark events in proton-proton collisions at [Formula: see text] TeV
    Sirunyan AM, Tumasyan A, Adam W, Asilar E, Bergauer T, Brandstetter J, et al.
    Eur Phys J C Part Fields, 2017;77(5):354.
    PMID: 28943789 DOI: 10.1140/epjc/s10052-017-4912-8
    A measurement of the top quark mass is reported in events containing a single top quark produced via the electroweak t channel. The analysis is performed using data from proton-proton collisions collected with the CMS detector at the LHC at a centre-of-mass energy of 8 TeV, corresponding to an integrated luminosity of 19.7 fb[Formula: see text]. Top quark candidates are reconstructed from their decay to a [Formula: see text] boson and a b quark, with the [Formula: see text] boson decaying leptonically to a muon and a neutrino. The final state signature and kinematic properties of single top quark events in the t channel are used to enhance the purity of the sample, suppressing the contribution from top quark pair production. A fit to the invariant mass distribution of reconstructed top quark candidates yields a value of the top quark mass of [Formula: see text]. This result is in agreement with the current world average, and represents the first measurement of the top quark mass in event topologies not dominated by top quark pair production, therefore contributing to future averages with partially uncorrelated systematic uncertainties and a largely uncorrelated statistical uncertainty.
  14. Search for Low Mass Vector Resonances Decaying to Quark-Antiquark Pairs in Proton-Proton Collisions at sqrt[s]=13  TeV
    Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Asilar E, Bergauer T, et al.
    Phys Rev Lett, 2017 Sep 15;119(11):111802.
    PMID: 28949210 DOI: 10.1103/PhysRevLett.119.111802
    A search is reported for a narrow vector resonance decaying to quark-antiquark pairs in proton-proton collisions at sqrt[s]=13  TeV, collected with the CMS detector at the LHC. The data sample corresponds to an integrated luminosity of 2.7   fb^{-1}. The vector resonance is produced at large transverse momenta, with its decay products merged into a single jet. The resulting signature is a peak over background in the distribution of the invariant mass of the jet. The results are interpreted in the framework of a leptophobic vector resonance and no evidence is found for such particles in the mass range of 100-300 GeV. Upper limits at 95% confidence level on the production cross section are presented in a region of mass-coupling phase space previously unexplored at the LHC. The region below 140 GeV has not been explored by any previous experiments.
  15. Fulltext Search for lepton flavour violating decays of heavy resonances and quantum black holes to an [Formula: see text] pair in proton-proton collisions at [Formula: see text]
    Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Asilar E, Bergauer T, et al.
    Eur Phys J C Part Fields, 2016;76(6):317.
    PMID: 28775662 DOI: 10.1140/epjc/s10052-016-4149-y
    A search for narrow resonances decaying to an electron and a muon is presented. The [Formula: see text] [Formula: see text] mass spectrum is also investigated for non-resonant contributions from the production of quantum black holes (QBHs). The analysis is performed using data corresponding to an integrated luminosity of 19.7[Formula: see text] collected in proton-proton collisions at a centre-of-mass energy of 8[Formula: see text] with the CMS detector at the LHC. With no evidence for physics beyond the standard model in the invariant mass spectrum of selected [Formula: see text] pairs, upper limits are set at 95 [Formula: see text] confidence level on the product of cross section and branching fraction for signals arising in theories with charged lepton flavour violation. In the search for narrow resonances, the resonant production of a [Formula: see text] sneutrino in R-parity violating supersymmetry is considered. The [Formula: see text] sneutrino is excluded for masses below 1.28[Formula: see text] for couplings [Formula: see text], and below 2.30[Formula: see text] for [Formula: see text] and [Formula: see text]. These are the most stringent limits to date from direct searches at high-energy colliders. In addition, the resonance searches are interpreted in terms of a model with heavy partners of the [Formula: see text] boson and the photon. In a framework of TeV-scale quantum gravity based on a renormalization of Newton's constant, the search for non-resonant contributions to the [Formula: see text] [Formula: see text] mass spectrum excludes QBH production below a threshold mass [Formula: see text] of 1.99[Formula: see text]. In models that invoke extra dimensions, the bounds range from 2.36[Formula: see text] for one extra dimension to 3.63[Formula: see text] for six extra dimensions. This is the first search for QBHs decaying into the [Formula: see text] [Formula: see text] final state.
  16. Search for Supersymmetry in pp Collisions at sqrt[s]=13  TeV in the Single-Lepton Final State Using the Sum of Masses of Large-Radius Jets
    Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Asilar E, Bergauer T, et al.
    Phys Rev Lett, 2017 Oct 13;119(15):151802.
    PMID: 29077436 DOI: 10.1103/PhysRevLett.119.151802
    Results are reported from a search for supersymmetric particles in proton-proton collisions in the final state with a single lepton, multiple jets, including at least one b-tagged jet, and large missing transverse momentum. The search uses a sample of proton-proton collision data at sqrt[s]=13  TeV recorded by the CMS experiment at the LHC, corresponding to an integrated luminosity of 35.9  fb^{-1}. The observed event yields in the signal regions are consistent with those expected from standard model backgrounds. The results are interpreted in the context of simplified models of supersymmetry involving gluino pair production, with gluino decay into either on- or off-mass-shell top squarks. Assuming that the top squarks decay into a top quark plus a stable, weakly interacting neutralino, scenarios with gluino masses up to about 1.9 TeV are excluded at 95% confidence level for neutralino masses up to about 1 TeV.
  17. Measurement of the B^{±} Meson Nuclear Modification Factor in Pb-Pb Collisions at sqrt[s_{NN}]=5.02  TeV
    Sirunyan AM, Tumasyan A, Adam W, Asilar E, Bergauer T, Brandstetter J, et al.
    Phys Rev Lett, 2017 Oct 13;119(15):152301.
    PMID: 29077459 DOI: 10.1103/PhysRevLett.119.152301
    The differential production cross sections of B^{±} mesons are measured via the exclusive decay channels B^{±}→J/ψK^{±}→μ^{+}μ^{-}K^{±} as a function of transverse momentum in pp and Pb-Pb collisions at a center-of-mass energy sqrt[s_{NN}]=5.02  TeV per nucleon pair with the CMS detector at the LHC. The pp(Pb-Pb) data set used for this analysis corresponds to an integrated luminosity of 28.0  pb^{-1} (351  μb^{-1}). The measurement is performed in the B^{±} meson transverse momentum range of 7 to 50  GeV/c, in the rapidity interval |y|<2.4. In this kinematic range, a strong suppression of the production cross section by about a factor of 2 is observed in the Pb-Pb system in comparison to the expectation from pp reference data. These results are found to be roughly compatible with theoretical calculations incorporating beauty quark diffusion and energy loss in a quark-gluon plasma.
  18. Fulltext A search for new phenomena in pp collisions at [Formula: see text] in final states with missing transverse momentum and at least one jet using the [Formula: see text] variable
    Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Asilar E, Bergauer T, et al.
    Eur Phys J C Part Fields, 2017;77(5):294.
    PMID: 28579921 DOI: 10.1140/epjc/s10052-017-4787-8
    A search for new phenomena is performed in final states containing one or more jets and an imbalance in transverse momentum in pp collisions at a centre-of-mass energy of 13[Formula: see text]. The analysed data sample, recorded with the CMS detector at the CERN LHC, corresponds to an integrated luminosity of 2.3[Formula: see text]. Several kinematic variables are employed to suppress the dominant background, multijet production, as well as to discriminate between other standard model and new physics processes. The search provides sensitivity to a broad range of new-physics models that yield a stable weakly interacting massive particle. The number of observed candidate events is found to agree with the expected contributions from standard model processes, and the result is interpreted in the mass parameter space of fourteen simplified supersymmetric models that assume the pair production of gluinos or squarks and a range of decay modes. For models that assume gluino pair production, masses up to 1575 and 975[Formula: see text] are excluded for gluinos and neutralinos, respectively. For models involving the pair production of top squarks and compressed mass spectra, top squark masses up to 400[Formula: see text] are excluded.
  19. Fulltext Search for direct pair production of supersymmetric top quarks decaying to all-hadronic final states in pp collisions at [Formula: see text]
    Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Asilar E, Bergauer T, et al.
    Eur Phys J C Part Fields, 2016;76(8):460.
    PMID: 28747851 DOI: 10.1140/epjc/s10052-016-4292-5
    Results are reported from a search for the pair production of top squarks, the supersymmetric partners of top quarks, in final states with jets and missing transverse momentum. The data sample used in this search was collected by the CMS detector and corresponds to an integrated luminosity of 18.9[Formula: see text] of proton-proton collisions at a centre-of-mass energy of 8[Formula: see text] produced by the LHC. The search features novel background suppression and prediction methods, including a dedicated top quark pair reconstruction algorithm. The data are found to be in agreement with the predicted backgrounds. Exclusion limits are set in simplified supersymmetry models with the top squark decaying to jets and an undetected neutralino, either through a top quark or through a bottom quark and chargino. Models with the top squark decaying via a top quark are excluded for top squark masses up to 755[Formula: see text] in the case of neutralino masses below 200[Formula: see text]. For decays via a chargino, top squark masses up to 620[Formula: see text] are excluded, depending on the masses of the chargino and neutralino.
  20. Search for Charged Higgs Bosons Produced via Vector Boson Fusion and Decaying into a Pair of W and Z Bosons Using pp Collisions at sqrt[s]=13  TeV
    Sirunyan AM, Tumasyan A, Adam W, Asilar E, Bergauer T, Brandstetter J, et al.
    Phys Rev Lett, 2017 Oct 06;119(14):141802.
    PMID: 29053305 DOI: 10.1103/PhysRevLett.119.141802
    A search for charged Higgs bosons produced via vector boson fusion and decaying into W and Z bosons using proton-proton collisions at sqrt[s]=13  TeV is presented. The data sample corresponds to an integrated luminosity of 15.2  fb^{-1} collected with the CMS detector in 2015 and 2016. The event selection requires three leptons (electrons or muons), two jets with large pseudorapidity separation and high dijet mass, and missing transverse momentum. The observation agrees with the standard model prediction. Limits on the vector boson fusion production cross section times branching fraction for new charged physical states are reported as a function of mass from 200 to 2000 GeV and interpreted in the context of Higgs triplet models.
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