Displaying publications 1 - 20 of 113 in total

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  1. Cheng Y, Lai OM, Tan CP, Panpipat W, Cheong LZ, Shen C
    ACS Appl Mater Interfaces, 2021 Jan 27;13(3):4146-4155.
    PMID: 33440928 DOI: 10.1021/acsami.0c17134
    Immobilization can be used to improve the stability of lipases and enhances lipase recovery and reusability, which increases its commercial value and industrial applications. Nevertheless, immobilization frequently causes conformational changes of the lipases, which decrease lipase catalytic activity. in the present work, we synthesized UIO-66 and grafted UIO-66 crystals with proline for immobilization of Candida rugosa lipase (CRL). As indicated by steady-state fluorescence microscopy, grafting of proline onto UIO-66 crystals induced beneficial conformational change in CRL. CRL immobilized on UIO-66/Pro (CRL@UIO-66/Pro) demonstrated higher enzyme activity and better recyclability than that immobilized on UIO-66 (CRL@UIO-66) in both hydrolysis (CRL@UIO-66/Pro: 0.34 U; CRL@UIO-66: 0.15 U) and transesterification (CRL@UIO-66/Pro: 0.93 U; CRL@UIO-66: 0.25 U) reactions. The higher values of kcat and kcat/Km of CRL@UIO-66/Pro also showed that it had better catalytic efficiency as compared to CRL@UIO-66. It is also worth noting that CRL@UIO-66/Pro (0.93 U) demonstrated a much higher transesterification activity as compared to free CRL (0.11 U), indicating that UIO-66/Pro has increased the solvent stability of CRL. Both CRL@UIO-66 and CRL@UIO-66/Pro were also used for the fabrication of biosensors for nitrofen with a wide linear range (0-100 μM), lower limit of detection, and good recovery rate.
  2. Wu YL, Zhou C, Liam CK, Wu G, Liu X, Zhong Z, et al.
    Ann Oncol, 2015 Sep;26(9):1883-1889.
    PMID: 26105600 DOI: 10.1093/annonc/mdv270
    BACKGROUND: The phase III, randomized, open-label ENSURE study (NCT01342965) evaluated first-line erlotinib versus gemcitabine/cisplatin (GP) in patients from China, Malaysia and the Philippines with epidermal growth factor receptor (EGFR) mutation-positive non-small-cell lung cancer (NSCLC).

    PATIENTS AND METHODS: Patients ≥18 years old with histologically/cytologically confirmed stage IIIB/IV EGFR mutation-positive NSCLC and Eastern Cooperative Oncology Group performance status 0-2 were randomized 1:1 to receive erlotinib (oral; 150 mg once daily until progression/unacceptable toxicity) or GP [G 1250 mg/m(2) i.v. days 1 and 8 (3-weekly cycle); P 75 mg/m(2) i.v. day 1, (3-weekly cycle) for up to four cycles]. Primary end point: investigator-assessed progression-free survival (PFS). Other end points include objective response rate (ORR), overall survival (OS), and safety.

    RESULTS: A total of 217 patients were randomized: 110 to erlotinib and 107 to GP. Investigator-assessed median PFS was 11.0 months versus 5.5 months, erlotinib versus GP, respectively [hazard ratio (HR), 0.34, 95% confidence interval (CI) 0.22-0.51; log-rank P < 0.0001]. Independent Review Committee-assessed median PFS was consistent (HR, 0.42). Median OS was 26.3 versus 25.5 months, erlotinib versus GP, respectively (HR, 0.91, 95% CI 0.63-1.31; log-rank P = .607). ORR was 62.7% for erlotinib and 33.6% for GP. Treatment-related serious adverse events (AEs) occurred in 2.7% versus 10.6% of erlotinib and GP patients, respectively. The most common grade ≥3 AEs were rash (6.4%) with erlotinib, and neutropenia (25.0%), leukopenia (14.4%), and anemia (12.5%) with GP.

    CONCLUSION: These analyses demonstrate that first-line erlotinib provides a statistically significant improvement in PFS versus GP in Asian patients with EGFR mutation-positive NSCLC (NCT01342965).

  3. Klionsky DJ, Abdel-Aziz AK, Abdelfatah S, Abdellatif M, Abdoli A, Abel S, et al.
    Autophagy, 2021 Jan;17(1):1-382.
    PMID: 33634751 DOI: 10.1080/15548627.2020.1797280
    In 2008, we published the first set of guidelines for standardizing research in autophagy. Since then, this topic has received increasing attention, and many scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Thus, it is important to formulate on a regular basis updated guidelines for monitoring autophagy in different organisms. Despite numerous reviews, there continues to be confusion regarding acceptable methods to evaluate autophagy, especially in multicellular eukaryotes. Here, we present a set of guidelines for investigators to select and interpret methods to examine autophagy and related processes, and for reviewers to provide realistic and reasonable critiques of reports that are focused on these processes. These guidelines are not meant to be a dogmatic set of rules, because the appropriateness of any assay largely depends on the question being asked and the system being used. Moreover, no individual assay is perfect for every situation, calling for the use of multiple techniques to properly monitor autophagy in each experimental setting. Finally, several core components of the autophagy machinery have been implicated in distinct autophagic processes (canonical and noncanonical autophagy), implying that genetic approaches to block autophagy should rely on targeting two or more autophagy-related genes that ideally participate in distinct steps of the pathway. Along similar lines, because multiple proteins involved in autophagy also regulate other cellular pathways including apoptosis, not all of them can be used as a specific marker for bona fide autophagic responses. Here, we critically discuss current methods of assessing autophagy and the information they can, or cannot, provide. Our ultimate goal is to encourage intellectual and technical innovation in the field.
  4. Li S, Li W, Cheng Y, Liu J, Wei G, Wang B
    Biodivers Data J, 2024;12:e113427.
    PMID: 38235166 DOI: 10.3897/BDJ.12.e113427
    BACKGROUND: The Asian leaf litter toads of the genus Leptobrachella Smith, 1925 (Anura, Megophryidae) inhabit the forest floor and rocky streams in hilly evergreen forests and are widely distributed from southern China, west to north-eastern India and Myanmar, through mainland Indochina to Peninsular Malaysia and the Island of Borneo.

    NEW INFORMATION: A new species of the Asian leaf litter toad genus Leptobrachella from Guizhou Province, China is described. Molecular phylogenetic analyses, based on mitochondrial 16S rRNA and COI genes and nuclear RAG1 gene sequences indicated that the new species is genetically divergent from its congeners. The new species could be distinguished from its congeners by a combination of the following characters: (1) body of medium size in males (SVL 31.9 - 32.9 mm); (2) distinct black spots present on flanks; (3) toes rudimentarily webbed, with wide lateral fringes; (4) skin on dorsum shagreened with fine tiny granules and short ridges; (5) heels overlapped when thighs are positioned at right angles to the body; (6) tibia-tarsal articulation reaching interior corner of the eye.A new species of the Asian leaf litter toad genus Leptobrachella from Guizhou Province, China is described. Molecular phylogenetic analyses, based on mitochondrial 16S rRNA and COI genes and nuclear RAG1 gene sequences indicated that the new species is genetically divergent from its congeners. The new species could be distinguished from its congeners by a combination of the following characters: (1) body of medium size in males (SVL 31.9 - 32.9 mm); (2) distinct black spots present on flanks; (3) toes rudimentarily webbed, with wide lateral fringes; (4) skin on dorsum shagreened with fine tiny granules and short ridges; (5) heels overlapped when thighs are positioned at right angles to the body; (6) tibia-tarsal articulation reaching interior corner of the eye.

  5. Liam CK, Ahmad AR, Hsia TC, Zhou J, Kim DW, Soo RA, et al.
    Clin Cancer Res, 2023 May 15;29(10):1879-1886.
    PMID: 36971777 DOI: 10.1158/1078-0432.CCR-22-3318
    PURPOSE: The final analyses of the INSIGHT phase II study evaluating tepotinib (a selective MET inhibitor) plus gefitinib versus chemotherapy in patients with MET-altered EGFR-mutant NSCLC (data cut-off: September 3, 2021).

    PATIENTS AND METHODS: Adults with advanced/metastatic EGFR-mutant NSCLC, acquired resistance to first-/second-generation EGFR inhibitors, and MET gene copy number (GCN) ≥5, MET:CEP7 ≥2, or MET IHC 2+/3+ were randomized to tepotinib 500 mg (450 mg active moiety) plus gefitinib 250 mg once daily, or chemotherapy. Primary endpoint was investigator-assessed progression-free survival (PFS). MET-amplified subgroup analysis was preplanned.

    RESULTS: Overall (N = 55), median PFS was 4.9 months versus 4.4 months [stratified HR, 0.67; 90% CI, 0.35-1.28] with tepotinib plus gefitinib versus chemotherapy. In 19 patients with MET amplification (median age 60.4 years; 68.4% never-smokers; median GCN 8.8; median MET/CEP7 2.8; 89.5% with MET IHC 3+), tepotinib plus gefitinib improved PFS (HR, 0.13; 90% CI, 0.04-0.43) and overall survival (OS; HR, 0.10; 90% CI, 0.02-0.36) versus chemotherapy. Objective response rate was 66.7% with tepotinib plus gefitinib versus 42.9% with chemotherapy; median duration of response was 19.9 months versus 2.8 months. Median duration of tepotinib plus gefitinib was 11.3 months (range, 1.1-56.5), with treatment >1 year in six (50.0%) and >4 years in three patients (25.0%). Seven patients (58.3%) had treatment-related grade ≥3 adverse events with tepotinib plus gefitinib and five (71.4%) had chemotherapy.

    CONCLUSIONS: Final analysis of INSIGHT suggests improved PFS and OS with tepotinib plus gefitinib versus chemotherapy in a subgroup of patients with MET-amplified EGFR-mutant NSCLC, after progression on EGFR inhibitors.

  6. Gray JE, Okamoto I, Sriuranpong V, Vansteenkiste J, Imamura F, Lee JS, et al.
    Clin Cancer Res, 2019 Nov 15;25(22):6644-6652.
    PMID: 31439584 DOI: 10.1158/1078-0432.CCR-19-1126
    PURPOSE: To assess the utility of the cobas EGFR Mutation Test, with tissue and plasma, for first-line osimertinib therapy for patients with EGFR-mutated (EGFRm; Ex19del and/or L858R) advanced or metastatic non-small cell lung cancer (NSCLC) from the FLAURA study (NCT02296125).

    EXPERIMENTAL DESIGN: Tumor tissue EGFRm status was determined at screening using the central cobas tissue test or a local tissue test. Baseline circulating tumor (ct)DNA EGFRm status was retrospectively determined with the central cobas plasma test.

    RESULTS: Of 994 patients screened, 556 were randomized (289 and 267 with central and local EGFR test results, respectively) and 438 failed screening. Of those randomized from local EGFR test results, 217 patients had available central test results; 211/217 (97%) were retrospectively confirmed EGFRm positive by central cobas tissue test. Using reference central cobas tissue test results, positive percent agreements with cobas plasma test results for Ex19del and L858R detection were 79% [95% confidence interval (CI), 74-84] and 68% (95% CI, 61-75), respectively. Progression-free survival (PFS) superiority with osimertinib over comparator EGFR-TKI remained consistent irrespective of randomization route (central/local EGFRm-positive tissue test). In both treatment arms, PFS was prolonged in plasma ctDNA EGFRm-negative (23.5 and 15.0 months) versus -positive patients (15.2 and 9.7 months).

    CONCLUSIONS: Our results support utility of cobas tissue and plasma testing to aid selection of patients with EGFRm advanced NSCLC for first-line osimertinib treatment. Lack of EGFRm detection in plasma was associated with prolonged PFS versus patients plasma EGFRm positive, potentially due to patients having lower tumor burden.

  7. Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Bergauer T, Dragicevic M, et al.
    Comput Softw Big Sci, 2020;4(1):10.
    PMID: 33196702 DOI: 10.1007/s41781-020-00041-z
    We describe a method to obtain point and dispersion estimates for the energies of jets arising from b quarks produced in proton-proton collisions at an energy of s = 13 TeV at the CERN LHC. The algorithm is trained on a large sample of simulated b jets and validated on data recorded by the CMS detector in 2017 corresponding to an integrated luminosity of 41 fb - 1 . A multivariate regression algorithm based on a deep feed-forward neural network employs jet composition and shape information, and the properties of reconstructed secondary vertices associated with the jet. The results of the algorithm are used to improve the sensitivity of analyses that make use of b jets in the final state, such as the observation of Higgs boson decay to b b ¯ .
  8. Yang Y, Li X, Li B, Mu L, Wang J, Cheng Y, et al.
    Immunol Invest, 2021 Feb;50(2-3):184-200.
    PMID: 32208776 DOI: 10.1080/08820139.2020.1718693
    BACKGROUND: Tumor necrosis factor superfamily member 4 (TNFSF4) has significant role in modulating autoimmune diseases (ADs) and single nucleotide polymorphism (SNP) is also related with the susceptibility to some diseases. So a meta-analysis aimed at systematically assessing the associations between TNFSF4 polymorphisms (rs2205960 G > A, rs704840 T > G and rs844648 G > A) and ADs risk was performed in Asians.

    METHODS: Total 14 eligible articles published before March 2019 involving 35 studies, of which 21 studies (16,109 cases and 26,378 controls) for rs2205960 G > A, 8 studies (2,424 cases and 3,692 controls) for rs704840 T > G, and 6 studies (3,839 cases and 5,867 controls) for rs844648 G > A were included. Effects of the three respective polymorphisms on the susceptibility to ADs were estimated by pooling the odds ratios (ORs) with their corresponding 95% confidence interval (95% CI) in allelic, dominant, recessive, heterozygous and homozygous models.

    RESULTS: The overall analysis revealed that all the rs2205960 G > A, rs704840 T > G and rs844648 G > A polymorphisms could increase the risk of ADs in allelic, dominant, recessive, heterozygous and homozygous models. Furthermore, subgroup analysis showed that both rs2205960 G > A and rs704840 T > G were significantly associated with the susceptibility to systemic lupus erythematosus (SLE). What's more, statistically significant association between rs2205960 G > A polymorphism and primary Sjögren's syndrome (pSS) susceptibility was also observed in allelic, dominant and heterozygous models.

    CONCLUSIONS: This current meta-analysis suggested that all of the three TNFSF4 polymorphisms may be associated with ADs susceptibility in Asians.

  9. Cho BC, Chewaskulyong B, Lee KH, Dechaphunkul A, Sriuranpong V, Imamura F, et al.
    J Thorac Oncol, 2019 01;14(1):99-106.
    PMID: 30240852 DOI: 10.1016/j.jtho.2018.09.004
    INTRODUCTION: Here we report efficacy and safety data of an Asian subset of the phase III FLAURA trial (NCT02296125), which compares osimertinib with standard of care (SoC) EGFR tyrosine kinase inhibitors (TKIs) in patients with previously untreated advanced NSCLC with tumors harboring exon 19 deletion (Ex19del)/L858R EGFR TKI-sensitizing mutations.

    METHODS: Eligible Asian patients (enrolled at Asian sites) who were at least 18 years of age (≥20 years in Japan) and had untreated EGFR-mutated advanced NSCLC were randomized 1:1 to receive osimertinib (80 mg, orally once daily) or an SoC EGFR TKI (gefitinib, 250 mg, or erlotinib, 150 mg, orally once daily). The primary end point was investigator-assessed progression-free survival (PFS). The key secondary end points were overall survival, objective response rate, central nervous system efficacy, and safety.

    RESULTS: The median PFS was 16.5 versus 11.0 months for the osimertinib and SoC EGFR TKI groups, respectively (hazard ratio = 0.54, 95% confidence interval: 0.41-0.72, p < 0.0001). The overall survival data were immature (24% maturity). The objective response rates were 80% for osimertinib and 75% for an SoC EGFR TKI. The median central nervous system PFS was not calculable for the osimertinib group and was 13.8 months for the SoC EGFR TKI group (hazard ratio = 0.55, 95% confidence interval: 0.25-1.17, p = 0.118). Fewer adverse events of grade 3 or higher (40% versus 48%) and fewer adverse events leading to treatment discontinuation (15% versus 21%) were reported with osimertinib versus with an SoC EGFR TKI, respectively.

    CONCLUSION: In this Asian population, first-line osimertinib demonstrated a clinically meaningful improvement in PFS over an SoC EGFR TKI, with a safety profile consistent with that for the overall FLAURA study population.

  10. Yang X, Ikhwanuddin M, Li X, Lin F, Wu Q, Zhang Y, et al.
    Mar Biotechnol (NY), 2018 Feb;20(1):20-34.
    PMID: 29152671 DOI: 10.1007/s10126-017-9784-2
    The molecular mechanism underlying sex determination and gonadal differentiation of the mud crab (Scylla paramamosain) has received considerable attention, due to the remarkably biological and economic differences between sexes. However, sex-biased genes, especially non-coding genes, which account for these differences, remain elusive in this crustacean species. In this study, the first de novo gonad transcriptome sequencing was performed to identify both differentially expressed genes and long non-coding RNAs (lncRNAs) between male and female S. paramamosain by using Illumina Hiseq2500. A total of 79,282,758 and 79,854,234 reads were generated from ovarian and testicular cDNA libraries, respectively. After filtrating and de novo assembly, 262,688 unigenes were produced from both libraries. Of these unigenes, 41,125 were annotated with known protein sequences in public databases. Homologous genes involved in sex determination and gonadal development pathways (Sxl-Tra/Tra-2-Dsx/Fru, Wnt4, thyroid hormone synthesis pathway, etc.) were identified. Three hundred and sixteen differentially expressed unigenes were further identified between both transcriptomes. Meanwhile, a total of 233,078 putative lncRNAs were predicted. Of these lncRNAs, 147 were differentially expressed between sexes. qRT-PCR results showed that nine lncRNAs negatively regulated the expression of eight genes, suggesting a potential role in sex differentiation. These findings will provide fundamental resources for further investigation on sex differentiation and regulatory mechanism in crustaceans.
  11. Shahrizaila N, Goh KJ, Kokubun N, Tan AH, Tan CY, Yuki N
    Muscle Nerve, 2014 Apr;49(4):558-63.
    PMID: 23893512 DOI: 10.1002/mus.23973
    Differing patterns of neurophysiological abnormalities have been reported in patients with Fisher syndrome. Fisher syndrome is rare, and few series have incorporated prospective serial studies to define the natural history of nerve conduction studies in Guillain-Barré syndrome.
  12. Zhang XC, Wang J, Shao GG, Wang Q, Qu X, Wang B, et al.
    Nat Commun, 2019 04 16;10(1):1772.
    PMID: 30992440 DOI: 10.1038/s41467-019-09762-1
    Deep understanding of the genomic and immunological differences between Chinese and Western lung cancer patients is of great importance for target therapy selection and development for Chinese patients. Here we report an extensive molecular and immune profiling study of 245 Chinese patients with non-small cell lung cancer. Tumor-infiltrating lymphocyte estimated using immune cell signatures is found to be significantly higher in adenocarcinoma (ADC, 72.5%) compared with squamous cell carcinoma (SQCC, 54.4%). The correlation of genomic alterations with immune signatures reveals that low immune infiltration was associated with EGFR mutations in ADC samples, PI3K and/or WNT pathway activation in SQCC. While KRAS mutations are found to be significantly associated with T cell infiltration in ADC samples. The SQCC patients with high antigen presentation machinery and cytotoxic T cell signature scores are found to have a prolonged overall survival time.
  13. Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Asilar E, Bergauer T, et al.
    Phys Rev Lett, 2020 Sep 04;125(10):102001.
    PMID: 32955327 DOI: 10.1103/PhysRevLett.125.102001
    The first study of charm quark diffusion with respect to the jet axis in heavy ion collisions is presented. The measurement is performed using jets with p_{T}^{jet}>60  GeV/c and D^{0} mesons with p_{T}^{D}>4  GeV/c in lead-lead (Pb-Pb) and proton-proton (pp) collisions at a nucleon-nucleon center-of-mass energy of sqrt[s_{NN}]=5.02  TeV, recorded by the CMS detector at the LHC. The radial distribution of D^{0} mesons with respect to the jet axis is sensitive to the production mechanisms of the meson, as well as to the energy loss and diffusion processes undergone by its parent parton inside the strongly interacting medium produced in Pb-Pb collisions. When compared to Monte Carlo event generators, the radial distribution in pp collisions is found to be well described by pythia, while the slope of the distribution predicted by sherpa is steeper than that of the data. In Pb-Pb collisions, compared to the pp results, the D^{0} meson distribution for 4
  14. 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.
  15. Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Asilar E, Bergauer T, et al.
    Phys Rev Lett, 2018 May 18;120(20):201801.
    PMID: 29864370 DOI: 10.1103/PhysRevLett.120.201801
    A search for narrow resonances decaying to bottom quark-antiquark pairs is presented, using a data sample of proton-proton collisions at sqrt[s]=8  TeV corresponding to an integrated luminosity of 19.7  fb^{-1}. The search is extended to masses lower than those reached in typical searches for resonances decaying into jet pairs at the LHC, by taking advantage of triggers that identify jets originating from bottom quarks. No significant excess of events is observed above the background predictions. Limits are set on the product of cross section and branching fraction to bottom quarks for spin 0, 1, and 2 resonances in the mass range of 325-1200 GeV. These results improve on the limits for resonances decaying into jet pairs in the 325-500 GeV mass range.
  16. Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Asilar E, Bergauer T, et al.
    Phys Rev Lett, 2018 Dec 14;121(24):241802.
    PMID: 30608761 DOI: 10.1103/PhysRevLett.121.241802
    Three of the most significant measured deviations from standard model predictions, the enhanced decay rate for B→D^{(*)}τν, hints of lepton universality violation in B→K^{(*)}ℓℓ decays, and the anomalous magnetic moment of the muon, can be explained by the existence of leptoquarks (LQs) with large couplings to third-generation quarks and masses at the TeV scale. The existence of these states can be probed at the LHC in high energy proton-proton collisions. A novel search is presented for pair production of LQs coupled to a top quark and a muon using data at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 35.9  fb^{-1}, recorded by the CMS experiment. No deviation from the standard model prediction has been observed and scalar LQs decaying exclusively into tμ are excluded up to masses of 1420 GeV. The results of this search are combined with those from previous searches for LQ decays into tτ and bν, which excluded scalar LQs below masses of 900 and 1080 GeV. Vector LQs are excluded up to masses of 1190 GeV for all possible combinations of branching fractions to tμ, tτ and bν. With this analysis, all relevant couplings of LQs with an electric charge of -1/3 to third-generation quarks are probed for the first time.
  17. Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Asilar E, Bergauer T, et al.
    Phys Rev Lett, 2018 Dec 14;121(24):242301.
    PMID: 30608764 DOI: 10.1103/PhysRevLett.121.242301
    Measurements of fragmentation functions for jets associated with an isolated photon are presented for the first time in pp and Pb-Pb collisions. The analysis uses data collected with the CMS detector at the CERN LHC at a nucleon-nucleon center-of-mass energy of 5.02 TeV. Fragmentation functions are obtained for jets with p_{T}^{jet}>30  GeV/c in events containing an isolated photon with p_{T}^{γ}>60  GeV/c, using charged tracks with transverse momentum p_{T}^{trk}>1  GeV/c in a cone around the jet axis. The association with an isolated photon constrains the initial p_{T} and azimuthal angle of the parton whose shower produced the jet. For central Pb-Pb collisions, modifications of the jet fragmentation functions are observed when compared to those measured in pp collisions, while no significant differences are found in the 50% most peripheral collisions. Jets in central Pb-Pb events show an excess (depletion) of low (high) p_{T} particles, with a transition around 3  GeV/c. This measurement shows for the first time the in-medium shower modifications of partons (quark dominated) with well-defined initial kinematics. It constitutes a new well-controlled reference for testing theoretical models of the parton passage through the quark-gluon plasma.
  18. Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Asilar E, Bergauer T, et al.
    Phys Rev Lett, 2018 Nov 30;121(22):221802.
    PMID: 30547617 DOI: 10.1103/PhysRevLett.121.221802
    The first evidence of events consistent with the production of a single top quark in association with a photon is reported. The analysis is based on proton-proton collisions at sqrt[s]=13  TeV and recorded by the CMS experiment in 2016, corresponding to an integrated luminosity of 35.9  fb^{-1}. Events are selected by requiring the presence of a muon (μ), a photon (γ), an imbalance in transverse momentum from an undetected neutrino (ν), and at least two jets (j) of which exactly one is identified as associated with the hadronization of a b quark. A multivariate discriminant based on topological and kinematic event properties is employed to separate signal from background processes. An excess above the background-only hypothesis is observed, with a significance of 4.4 standard deviations. A fiducial cross section is measured for isolated photons with transverse momentum greater than 25 GeV in the central region of the detector. The measured product of the cross section and branching fraction is σ(pp→tγj)B(t→μνb)=115±17(stat)±30(syst)  fb, which is consistent with the standard model prediction.
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