Displaying publications 1 - 20 of 38 in total

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  1. Fulltext Spatial correlation network characteristics of embodied carbon transfer in global agricultural trade
    Wang G, Guo Q, Zhou X, Zhang F
    Environ Sci Pollut Res Int, 2023 Jan;30(1):2315-2328.
    PMID: 35930151 DOI: 10.1007/s11356-022-22337-w
    Agricultural carbon emission is an important cause of climate change, and the carbon transfer caused by agricultural trade is a key area related to carbon emissions of all countries. Based on the Eora database, this paper aims to constructs a multi-region input-output database of 185 countries or regions, analyzes a spatial correlation network of embodied net carbon transfer in global agricultural trade by using UCINET, selects multi-dimensional network measurement indicators, and comprehensively studies the global evolution characteristics and functional features of network plate role of embodied carbon transfer in the global agricultural trade. The result shows that the embodied net carbon transfer network of global agricultural trade is densely connected, the spatial correlation spillover effect is significant, and the edge of the network core structure is clear. On the one hand, the top four countries or regions in terms of embodied carbon outflow in agricultural trade are the USA, Australia, Vietnam, and China. On the other hand, the top four countries or regions of embodied carbon inflow are Malaysia, Central Africa, Singapore, and Serbia. From the perspective of outdegree, indegree, proximity centrality, and intermediary centrality, Cambodia, the Netherlands, Vietnam, Ghana, and South Africa, with the high frequency of the shortest path of the globally embodied net carbon transfer network, have a strong influence and linking facility in spatial correlation and have a strong control ability to the spatial correlation of other countries or regions. The embodied carbon emission network of global agricultural trade can be divided into four sectors: main spillover, two-way spillover, broker, and main benefit. The main spillover segment, constituted by the USA, India, Germany, and China, has significant embodied carbon spillover effects on the internal segment and other segments. It is the main embodied carbon spillover sector of embodied net carbon transfer of global agricultural trade. Countries should reasonably allocate the responsibility of carbon reduction according to the trading embodied carbon transfer and made efforts to optimize the export structure of agricultural products.
  2. Development of regenerated cellulose/halloysites nanocomposites via ionic liquids
    Hanid NA, Wahit MU, Guo Q, Mahmoodian S, Soheilmoghaddam M
    Carbohydr Polym, 2014 Jan;99:91-7.
    PMID: 24274483 DOI: 10.1016/j.carbpol.2013.07.080
    In this study, regenerated cellulose/halloysites (RC/HNT) nanocomposites with different nanofillers loading were fabricated by dissolving the cellulose in 1-ethyl-3-methylimidazolium chloride (EMIMCl) ionic liquid. The films were prepared via solution casting method and were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The mechanical properties were investigated by tensile testing. It clearly displayed a good enhancement of both tensile strength and Young's modulus with HNT loading up to 5 wt%. As the HNT loadings increased to 5 wt%, the thermal behaviour and water resistance rate was also increased. The TEM and SEM images also depicted even dispersion of the HNT and a good intertubular interaction between the HNT and the cellulose matrix.
  3. Antioxidant and antihypertensive effects of garlic protein and its hydrolysates and the related mechanism
    Gao X, Xue Z, Ma Q, Guo Q, Xing L, Santhanam RK, et al.
    J Food Biochem, 2020 02;44(2):e13126.
    PMID: 31877235 DOI: 10.1111/jfbc.13126
    Garlic protein (GP) was enzymatically hydrolyzed using pepsin and trypsin followed by the evaluation of antioxidant and angiotensin-converting enzyme (ACE) inhibitory activities of GP and its hydrolysates. The antihypertensive effects of GP and its hydrolysates were determined in vivo. The results showed that GP and its hydrolysates namely GPH-P (pepsin) and GPH-T (trypsin) possessed appreciable antioxidant and ACE inhibitory activities. The ACE inhibitory activity of GP, GPH-T, and GPH-P was in consistent with their antioxidant activities. GP and its hydrolysates offered significant protective effects against H2 O2 -induced oxidative damage (p 
  4. Can environmentally friendly technology help China to achieve a carbon neutrality target by 2060? An asymmetrical based study in China
    Nurgazina Z, Guo Q, Ali U, Sharif A, Khan ZA, Kartal MT, et al.
    Environ Sci Pollut Res Int, 2023 Jun 13.
    PMID: 37308627 DOI: 10.1007/s11356-023-27904-3
    Climate change-related environmental challenges are prompting an increasing number of countries to set carbon-neutral targets. Since 2007, China has pursued numerous initiatives to attain carbon neutrality by 2060, including increasing the percentage of non-fossil energy, developing zero-emission and low-emission technologies, and taking actions that reduce CO2 emissions or boost carbon sinks. As a result, utilizing quarterly data from 2008/Q1 to 2021/Q4, and applying the nonlinear autoregressive distributed lag (NARDL) approach, this study evaluates the effectiveness of the measures taken by China to improve the ecological situation. The results of the study show that the measures enacted to reduce CO2 emissions did not accomplish their ultimate purpose. Specifically: (i) high-speed railways and new energy vehicles do not improve the environment in the long run; (ii) investments and patents in the energy sector, as well as low-carbon sources, will degrade the environment; (iii) only investments in the treatment of environmental pollution will improve the ecological situation. Various policy implications are suggested based on the empirical results in order to attain environmental sustainability.
  5. Expression pattern of AGPATs isoforms indicate different functions during the triacylglyceride synthesis in Chinese mitten crab, Eriocheir sinensis
    Pan K, Zhu B, Wang L, Guo Q, Shu-Chien AC, Wu X
    Comp Biochem Physiol A Mol Integr Physiol, 2024 Jan;287:111535.
    PMID: 37852318 DOI: 10.1016/j.cbpa.2023.111535
    The 1-acylglycerol-3-phosphate acyltransferase (AGPAT) acts as a crucial enzyme in the process of triacylglycerol (TAG) synthesis, enabling the acylation of lysophosphatidic acid (LPA) into phosphatidic acid (PA). In order to decode the distinctive roles of AGPAT isoforms in the TAG production pathway, three AGPAT isoforms were detected for the first time in the Chinese mitten crab Eriocheir sinensis (Es-agpat2, Es-agpat3, and Es-agpat4). The mRNA levels of Es-agpat2 and Es-agpat4 demonstrated a conspicuous presence in the hepatopancreas, with subsequent high levels in the heart, muscle, and thoracic ganglion. On the other hand, the thoracic ganglion exhibited abundant levels of Es-agpat3, while other tissues recorded relatively low expression levels. Observing the molting cycle of E. sinensis, the hepatopancreas showed minimum expression levels of Es-agpat2 and Es-agpat4 at stage A/B. A peak at stage C was noted, which was then followed by a gradual drop until stage E. For the ovarian development cycle, stage II witnessed the maximum expression level of Es-agpat2 and Es-agpat4, succeeded by a sharp fall in stage III. After this, there was an increasing trend from stage III up to stage V. Expression of Es-agpat3 in the hepatopancreas was consistently lower than Es-agpat2 and Es-agpat4 during either the molting or ovarian development. However, in terms of ovarian expression, Es-agpat3 outperformed Es-agpat2 and Es-agpat4. It exhibited a steep increase in expression, peaking at stage II and subsequently diminishing. In situ hybridization (ISH) revealed that in stages II and IV hepatopancreas, Es-agpat4-mRNA was primarily located in fibrillar cells (F cell) and resorptive cells (R cell), with no signal from Es-agpat3. During stage II of ovarian development, both Es-agpat3-mRNA and Es-agpat4-mRNA were located in the cytoplasm of previtellogenic oocyte (PRO) and endogenous vitellogenic oocyte (EN), with no expression at stage IV. Additionally, the silencing of Es-agpat2 and Es-agpat4 caused a downward trend in the expression levels of all subsequent genes in the E. sinensis TAG synthesis pathway. To sum up, these findings suggest that the three Es-agpats may have unique functions in TAG synthesis during either the molting process or ovarian maturation of E. sinensis.
  6. Effect of carnosine supplementation on lipid profile, fasting blood glucose, HbA1C and insulin resistance: A systematic review and meta-analysis of long-term randomized controlled trials
    Peng W, Mao P, Liu L, Chen K, Zhong Y, Xia W, et al.
    Complement Ther Med, 2020 Jan;48:102241.
    PMID: 31987255 DOI: 10.1016/j.ctim.2019.102241
    OBJECTIVE: Glucose disorders and dyslipidemia are closely associated with obesity and metabolic disease. The purpose of this study was to investigate the effect of Carnosine supplementation on lipid profile, fasting blood glucose, HbA1C and Insulin resistance.

    METHOD: MEDLINE/PubMed, Scopus and Web of sciences were investigated to identify relevant articles up to June 2019. The search strategy combined the Medical Subject Heading and Title and/or abstract keywords. The combined effect sizes were calculated as weight mean difference (WMD) using the random-effects model. Between study heterogeneity was evaluated by the Cochran's Q test and I2.

    RESULTS: Four RCTs studies investigated Carnosine use versus any control for at least 2 weeks were identified and analyzed. Overall results from the random-effects model on included studies, with 184 participants, indicated that carnosine intervention reduced HbA1C levels in intervention vs control groups (WMD: -0.92 %, 95 % CI: -1.20, -0.63, I2:69 %). Four studies, including a total of 183 participants, reported TG changes as an outcome measure variable, but combined results did not show significant reduction in this outcome (WMD: -14.46 mg/dl, 95 % CI: -29.11, 0.19, I2:94 %). Furthermore, combined results did not show any significant change in HOMA-IR, Cholesterol, fasting blood sugar, or HDL-C.

    CONCLUSION: Carnosine supplementation results in a decrease in HbA1C, but elicits no effect on HOMA-IR, Cholesterol, fasting blood sugar, TG and HDL-C. Future studies with a larger sample sizes, varied doses of carnosine, and population-specific sub-groups are warranted to confirm, and enhance, the veracity of our findings.

  7. Guideline for the diagnosis, treatment and long-term management of cutaneous lupus erythematosus
    Lu Q, Long H, Chow S, Hidayat S, Danarti R, Listiawan Y, et al.
    J Autoimmun, 2021 09;123:102707.
    PMID: 34364171 DOI: 10.1016/j.jaut.2021.102707
    Cutaneous lupus erythematosus (CLE) is an inflammatory, autoimmune disease encompassing a broad spectrum of subtypes including acute, subacute, chronic and intermittent CLE. Among these, chronic CLE can be further classified into several subclasses of lupus erythematosus (LE) such as discoid LE, verrucous LE, LE profundus, chilblain LE and Blaschko linear LE. To provide all dermatologists and rheumatologists with a practical guideline for the diagnosis, treatment and long-term management of CLE, this evidence- and consensus-based guideline was developed following the checklist established by the international Reporting Items for Practice Guidelines in Healthcare (RIGHT) Working Group and was registered at the International Practice Guideline Registry Platform. With the joint efforts of the Asian Dermatological Association (ADA), the Asian Academy of Dermatology and Venereology (AADV) and the Lupus Erythematosus Research Center of Chinese Society of Dermatology (CSD), a total of 25 dermatologists, 7 rheumatologists, one research scientist on lupus and 2 methodologists, from 16 countries/regions in Asia, America and Europe, participated in the development of this guideline. All recommendations were agreed on by at least 80% of the 32 voting physicians. As a consensus, diagnosis of CLE is mainly based on the evaluation of clinical and histopathological manifestations, with an exclusion of SLE by assessment of systemic involvement. For localized CLE lesions, topical corticosteroids and topical calcineurin inhibitors are first-line treatment. For widespread or severe CLE lesions and (or) cases resistant to topical treatment, systemic treatment including antimalarials and (or) short-term corticosteroids can be added. Notably, antimalarials are the first-line systemic treatment for all types of CLE, and can also be used in pregnant patients and pediatric patients. Second-line choices include thalidomide, retinoids, dapsone and MTX, whereas MMF is third-line treatment. Finally, pulsed-dye laser or surgery can be added as fourth-line treatment for localized, refractory lesions of CCLE in cosmetically unacceptable areas, whereas belimumab may be used as fourth-line treatment for widespread CLE lesions in patients with active SLE, or recurrence of ACLE during tapering of corticosteroids. As for management of the disease, patient education and a long-term follow-up are necessary. Disease activity, damage of skin and other organs, quality of life, comorbidities and possible adverse events are suggested to be assessed in every follow-up visit, when appropriate.
  8. Fulltext Evidence that breast cancer risk at the 2q35 locus is mediated through IGFBP5 regulation
    Ghoussaini M, Edwards SL, Michailidou K, Nord S, Cowper-Sal Lari R, Desai K, et al.
    Nat Commun, 2014 Sep 23;4:4999.
    PMID: 25248036 DOI: 10.1038/ncomms5999
    GWAS have identified a breast cancer susceptibility locus on 2q35. Here we report the fine mapping of this locus using data from 101,943 subjects from 50 case-control studies. We genotype 276 SNPs using the 'iCOGS' genotyping array and impute genotypes for a further 1,284 using 1000 Genomes Project data. All but two, strongly correlated SNPs (rs4442975 G/T and rs6721996 G/A) are excluded as candidate causal variants at odds against >100:1. The best functional candidate, rs4442975, is associated with oestrogen receptor positive (ER+) disease with an odds ratio (OR) in Europeans of 0.85 (95% confidence interval=0.84-0.87; P=1.7 × 10(-43)) per t-allele. This SNP flanks a transcriptional enhancer that physically interacts with the promoter of IGFBP5 (encoding insulin-like growth factor-binding protein 5) and displays allele-specific gene expression, FOXA1 binding and chromatin looping. Evidence suggests that the g-allele confers increased breast cancer susceptibility through relative downregulation of IGFBP5, a gene with known roles in breast cell biology.
  9. Fulltext Identification of ten variants associated with risk of estrogen-receptor-negative breast cancer
    Milne RL, Kuchenbaecker KB, Michailidou K, Beesley J, Kar S, Lindström S, et al.
    Nat Genet, 2017 Dec;49(12):1767-1778.
    PMID: 29058716 DOI: 10.1038/ng.3785
    Most common breast cancer susceptibility variants have been identified through genome-wide association studies (GWAS) of predominantly estrogen receptor (ER)-positive disease. We conducted a GWAS using 21,468 ER-negative cases and 100,594 controls combined with 18,908 BRCA1 mutation carriers (9,414 with breast cancer), all of European origin. We identified independent associations at P < 5 × 10-8 with ten variants at nine new loci. At P < 0.05, we replicated associations with 10 of 11 variants previously reported in ER-negative disease or BRCA1 mutation carrier GWAS and observed consistent associations with ER-negative disease for 105 susceptibility variants identified by other studies. These 125 variants explain approximately 16% of the familial risk of this breast cancer subtype. There was high genetic correlation (0.72) between risk of ER-negative breast cancer and breast cancer risk for BRCA1 mutation carriers. These findings may lead to improved risk prediction and inform further fine-mapping and functional work to better understand the biological basis of ER-negative breast cancer.
  10. Observation of the B_{s}^{0}→X(3872)ϕ Decay
    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.
  11. Observation of the Production of Three Massive Gauge Bosons at sqrt[s]=13  TeV
    Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Bergauer T, Dragicevic M, et al.
    Phys Rev Lett, 2020 Oct 09;125(15):151802.
    PMID: 33095594 DOI: 10.1103/PhysRevLett.125.151802
    The first observation is reported of the combined production of three massive gauge bosons (VVV with V=W, Z) in proton-proton collisions at a center-of-mass energy of 13 TeV. The analysis is based on a data sample recorded by the CMS experiment at the CERN LHC corresponding to an integrated luminosity of 137  fb^{-1}. The searches for individual WWW, WWZ, WZZ, and ZZZ production are performed in final states with three, four, five, and six leptons (electrons or muons), or with two same-sign leptons plus one or two jets. The observed (expected) significance of the combined VVV production signal is 5.7 (5.9) standard deviations and the corresponding measured cross section relative to the standard model prediction is 1.02_{-0.23}^{+0.26}. The significances of the individual WWW and WWZ production are 3.3 and 3.4 standard deviations, respectively. Measured production cross sections for the individual triboson processes are also reported.
  12. Evidence for Top Quark Production in Nucleus-Nucleus Collisions
    Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Bergauer T, Dragicevic M, et al.
    Phys Rev Lett, 2020 Nov 27;125(22):222001.
    PMID: 33315428 DOI: 10.1103/PhysRevLett.125.222001
    Ultrarelativistic heavy ion collisions recreate in the laboratory the thermodynamical conditions prevailing in the early universe up to 10^{-6}  sec, thereby allowing the study of the quark-gluon plasma (QGP), a state of quantum chromodynamics (QCD) matter with deconfined partons. The top quark, the heaviest elementary particle known, is accessible in nucleus-nucleus collisions at the CERN LHC, and constitutes a novel probe of the QGP. Here, we report the first evidence for the production of top quarks in nucleus-nucleus collisions, using lead-lead collision data at a nucleon-nucleon center-of-mass energy of 5.02 TeV recorded by the CMS experiment. Two methods are used to measure the cross section for top quark pair production (σ_{tt[over ¯]}) via the selection of charged leptons (electrons or muons) and bottom quarks. One method relies on the leptonic information alone, and the second one exploits, in addition, the presence of bottom quarks. The measured cross sections, σ_{tt[over ¯]}=2.54_{-0.74}^{+0.84} and 2.03_{-0.64}^{+0.71}  μb, respectively, are compatible with expectations from scaled proton-proton data and QCD predictions.
  13. Observation of a New Excited Beauty Strange Baryon Decaying to Ξ_{b}^{-}π^{+}π^{-}
    Sirunyan AM, Tumasyan A, Adam W, Andrejkovic JW, Bergauer T, Chatterjee S, et al.
    Phys Rev Lett, 2021 Jun 25;126(25):252003.
    PMID: 34241504 DOI: 10.1103/PhysRevLett.126.252003
    The Ξ_{b}^{-}π^{+}π^{-} invariant mass spectrum is investigated with an event sample of proton-proton collisions at sqrt[s]=13  TeV, collected by the CMS experiment at the LHC in 2016-2018 and corresponding to an integrated luminosity of 140  fb^{-1}. The ground state Ξ_{b}^{-} is reconstructed via its decays to J/ψΞ^{-} and J/ψΛK^{-}. A narrow resonance, labeled Ξ_{b}(6100)^{-}, is observed at a Ξ_{b}^{-}π^{+}π^{-} invariant mass of 6100.3±0.2(stat)±0.1(syst)±0.6(Ξ_{b}^{-})  MeV, where the last uncertainty reflects the precision of the Ξ_{b}^{-} baryon mass. The upper limit on the Ξ_{b}(6100)^{-} natural width is determined to be 1.9  MeV at 95% confidence level. The low Ξ_{b}(6100)^{-} signal yield observed in data does not allow a measurement of the quantum numbers of the new state. However, following analogies with the established excited Ξ_{c} baryon states, the new Ξ_{b}(6100)^{-} resonance and its decay sequence are consistent with the orbitally excited Ξ_{b}^{-} baryon, with spin and parity quantum numbers J^{P}=3/2^{-}.
  14. Measurement of the Wγ Production Cross Section in Proton-Proton Collisions at sqrt[s]=13  TeV and Constraints on Effective Field Theory Coefficients
    Sirunyan AM, Tumasyan A, Adam W, Andrejkovic JW, Bergauer T, Chatterjee S, et al.
    Phys Rev Lett, 2021 Jun 25;126(25):252002.
    PMID: 34241533 DOI: 10.1103/PhysRevLett.126.252002
    A fiducial cross section for Wγ production in proton-proton collisions is measured at a center-of-mass energy of 13 TeV in 137  fb^{-1} of data collected using the CMS detector at the LHC. The W→eν and μν decay modes are used in a maximum-likelihood fit to the lepton-photon invariant mass distribution to extract the combined cross section. The measured cross section is compared with theoretical expectations at next-to-leading order in quantum chromodynamics. In addition, 95% confidence level intervals are reported for anomalous triple-gauge couplings within the framework of effective field theory.
  15. Constraints on the Initial State of Pb-Pb Collisions via Measurements of Z-Boson Yields and Azimuthal Anisotropy at sqrt[s_{NN}]=5.02  TeV
    Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Bergauer T, Dragicevic M, et al.
    Phys Rev Lett, 2021 Sep 03;127(10):102002.
    PMID: 34533355 DOI: 10.1103/PhysRevLett.127.102002
    The CMS experiment at the LHC has measured the differential cross sections of Z bosons decaying to pairs of leptons, as functions of transverse momentum and rapidity, in lead-lead collisions at a nucleon-nucleon center-of-mass energy of 5.02  TeV. The measured Z boson elliptic azimuthal anisotropy coefficient is compatible with zero, showing that Z bosons do not experience significant final-state interactions in the medium produced in the collision. Yields of Z bosons are compared to Glauber model predictions and are found to deviate from these expectations in peripheral collisions, indicating the presence of initial collision geometry and centrality selection effects. The precision of the measurement allows, for the first time, for a data-driven determination of the nucleon-nucleon integrated luminosity as a function of lead-lead centrality, thereby eliminating the need for its estimation based on a Glauber model.
  16. Observation of Forward Neutron Multiplicity Dependence of Dimuon Acoplanarity in Ultraperipheral Pb-Pb Collisions at sqrt[s_{NN}]=5.02  TeV
    Sirunyan AM, Tumasyan A, Adam W, Bergauer T, Dragicevic M, Erö J, et al.
    Phys Rev Lett, 2021 Sep 17;127(12):122001.
    PMID: 34597080 DOI: 10.1103/PhysRevLett.127.122001
    The first measurement of the dependence of γγ→μ^{+}μ^{-} production on the multiplicity of neutrons emitted very close to the beam direction in ultraperipheral heavy ion collisions is reported. Data for lead-lead interactions at sqrt[s_{NN}]=5.02  TeV, with an integrated luminosity of approximately 1.5  nb^{-1}, are collected using the CMS detector at the LHC. The azimuthal correlations between the two muons in the invariant mass region 88.3. The back-to-back correlation structure from leading-order photon-photon scattering is found to be significantly broader for events with a larger number of emitted neutrons from each nucleus, corresponding to interactions with a smaller impact parameter. This observation provides a data-driven demonstration that the average transverse momentum of photons emitted from relativistic heavy ions has an impact parameter dependence. These results provide new constraints on models of photon-induced interactions in ultraperipheral collisions. They also provide a baseline to search for possible final-state effects on lepton pairs caused by traversing a quark-gluon plasma produced in hadronic heavy ion collisions.
  17. Fulltext Development and validation of HERWIG 7 tunes from CMS underlying-event measurements
    Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Bergauer T, Dragicevic M, et al.
    Eur Phys J C Part Fields, 2021;81(4):312.
    PMID: 34727148 DOI: 10.1140/epjc/s10052-021-08949-5
    This paper presents new sets of parameters ("tunes") for the underlying-event model of the H E R W I G 7 event generator. These parameters control the description of multiple-parton interactions (MPI) and colour reconnection in H E R W I G 7 , and are obtained from a fit to minimum-bias data collected by the CMS experiment at s = 0.9 , 7, and 13 Te . The tunes are based on the NNPDF 3.1 next-to-next-to-leading-order parton distribution function (PDF) set for the parton shower, and either a leading-order or next-to-next-to-leading-order PDF set for the simulation of MPI and the beam remnants. Predictions utilizing the tunes are produced for event shape observables in electron-positron collisions, and for minimum-bias, inclusive jet, top quark pair, and Z and W boson events in proton-proton collisions, and are compared with data. Each of the new tunes describes the data at a reasonable level, and the tunes using a leading-order PDF for the simulation of MPI provide the best description of the data.
  18. Fulltext MUSiC: a model-unspecific search for new physics in proton-proton collisions at s = 13 TeV
    CMS Collaboration, Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Bergauer T, et al.
    Eur Phys J C Part Fields, 2021;81(7):629.
    PMID: 34727144 DOI: 10.1140/epjc/s10052-021-09236-z
    Results of the Model Unspecific Search in CMS (MUSiC), using proton-proton collision data recorded at the LHC at a centre-of-mass energy of 13 TeV , corresponding to an integrated luminosity of 35.9 fb - 1 , are presented. The MUSiC analysis searches for anomalies that could be signatures of physics beyond the standard model. The analysis is based on the comparison of observed data with the standard model prediction, as determined from simulation, in several hundred final states and multiple kinematic distributions. Events containing at least one electron or muon are classified based on their final state topology, and an automated search algorithm surveys the observed data for deviations from the prediction. The sensitivity of the search is validated using multiple methods. No significant deviations from the predictions have been observed. For a wide range of final state topologies, agreement is found between the data and the standard model simulation. This analysis complements dedicated search analyses by significantly expanding the range of final states covered using a model independent approach with the largest data set to date to probe phase space regions beyond the reach of previous general searches.
  19. Fulltext Combined searches for the production of supersymmetric top quark partners in proton-proton collisions at s = 13 Te
    Tumasyan A, Adam W, Andrejkovic JW, Bergauer T, Chatterjee S, Dragicevic M, et al.
    Eur Phys J C Part Fields, 2021;81(11):970.
    PMID: 34793584 DOI: 10.1140/epjc/s10052-021-09721-5
    A combination of searches for top squark pair production using proton-proton collision data at a center-of-mass energy of 13 Te at the CERN LHC, corresponding to an integrated luminosity of 137 fb - 1 collected by the CMS experiment, is presented. Signatures with at least 2 jets and large missing transverse momentum are categorized into events with 0, 1, or 2 leptons. New results for regions of parameter space where the kinematical properties of top squark pair production and top quark pair production are very similar are presented. Depending on the model, the combined result excludes a top squark mass up to 1325 Ge for a massless neutralino, and a neutralino mass up to 700 Ge for a top squark mass of 1150 Ge . Top squarks with masses from 145 to 295 Ge , for neutralino masses from 0 to 100 Ge , with a mass difference between the top squark and the neutralino in a window of 30 Ge around the mass of the top quark, are excluded for the first time with CMS data. The results of theses searches are also interpreted in an alternative signal model of dark matter production via a spin-0 mediator in association with a top quark pair. Upper limits are set on the cross section for mediator particle masses of up to 420 Ge .
  20. Fulltext Precision luminosity measurement in proton-proton collisions at s = 13 TeV in 2015 and 2016 at CMS
    Sirunyan AM, Tumasyan A, Adam W, Andrejkovic JW, Bergauer T, Chatterjee S, et al.
    Eur Phys J C Part Fields, 2021;81(9):800.
    PMID: 34781320 DOI: 10.1140/epjc/s10052-021-09538-2
    The measurement of the luminosity recorded by the CMS detector installed at LHC interaction point 5, using proton-proton collisions at s = 13 TeV in 2015 and 2016, is reported. The absolute luminosity scale is measured for individual bunch crossings using beam-separation scans (the van der Meer method), with a relative precision of 1.3 and 1.0% in 2015 and 2016, respectively. The dominant sources of uncertainty are related to residual differences between the measured beam positions and the ones provided by the operational settings of the LHC magnets, the factorizability of the proton bunch spatial density functions in the coordinates transverse to the beam direction, and the modeling of the effect of electromagnetic interactions among protons in the colliding bunches. When applying the van der Meer calibration to the entire run periods, the integrated luminosities when CMS was fully operational are 2.27 and 36.3 fb - 1 in 2015 and 2016, with a relative precision of 1.6 and 1.2%, respectively. These are among the most precise luminosity measurements at bunched-beam hadron colliders.
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