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Fulltext Guidelines for the use and interpretation of assays for monitoring autophagy (4th edition)1

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.
High seroprevalence of anti-Fasciola antibody among cattle farm workers and dwellers in Kelantan

Najib MA, Noor-Izani NJ, Wan-Nor-Amilah WAW, Wong WK, Faez AM

Trop Biomed, 2020 Jun 01;37(2):389-396.
PMID: 33612808

Human fascioliasis is a public health problem particularly in areas where ruminants are raised. The aims of this study were to determine the seroprevalence of anti-Fasciola antibody and the associated risk factors among cattle farm workers and dwellers in Kelantan. A total of 90 blood samples were collected in this cross-sectional study. A set of validated questionnaire was used to obtain information on socio-demographic profiles and dietary habits of participants. The sera were subjected to enzyme linked immunosorbent assay (ELISA) for the detection of anti-Fasciola IgG antibody. The association between seropositivity and the significant risk factors were determined via logistic regression. From the result, serological screening revealed 60 (67%) participants positive for anti-Fasciola IgG antibody. The factors found to be significantly associated with seropositivity against anti-Fasciola IgG antibody were the age group of 18 years old and above with calculated odds ratio of 3.2 times (p=0.032) and the duration of farming activities of more than 5 years with calculated odds ratio of 2.6 times (p=0.036). In conclusion, Fasciola infection is prevalent among cattle farm workers and dwellers in Kelantan.
Fulltext Identification of Entamoeba histolytica trophozoites in fresh stool sample: comparison of three staining techniques and study on the viability period of the trophozoites

Tan ZN, Wong WK, Nik Zairi Z, Abdullah B, Rahmah N, Zeehaida M, et al.

Trop Biomed, 2010 Apr;27(1):79-88.
PMID: 20562817 MyJurnal

Entamoeba histolytica causes about 50 million infections worldwide with a death rate of over 100,000 annually. In endemic developing countries where resources are limited, microscopic examinations based on Wheatley trichrome staining is commonly used for diagnosis of intestinal amoebiasis. Other than being a time-consuming method, it must be performed promptly after stool collection as trophozoites disintegrate rapidly in faeces. The aim of this study was to compare the efficacies of Eosin-Y, Wheatley trichrome and Iodine stains in delineating the diagnostic features of the parasite, and subsequently to determine the suitable microscopy observation period for detection of erythrophagocytic and non-erythrophagocytic trophozoites spiked in semi-solid stool sample. Wheatley trichrome staining technique was performed using the standard method while the other two techniques were performed on the slides by mixing the respective staining solution with the spiked stool sample. One million of axenically cultured non-erythrophagocytic E. histolytica and erythrophagocytic E. histolytica were separately spiked into 2 g of fresh semisolid faeces. Percentage viability of the trophozoites in the spiked stool sample was determined at 30 minute intervals for eight hours using the 0.4% Trypan blue exclusion method. The results showed that Eosin-Y and Wheatley trichrome stained the karyosome and chromatin granules better as compared to Iodine stain. The percentage viability of non-erythrophagocytic trophozoites decreased faster than the erythrophagocytic form in the first 5 hours and both dropped to ~10% in the 6th hour spiked sample. In conclusion, Eosin-Y staining technique was found to be the easiest to perform, most rapid and as accurate as the commonly used Wheatley trichrome technique; Eosin-Y stained slide sealed with DPX could also be kept as a permanent record. A period not exceeding 6 hours after stool collection was found to be the most suitable in order to obtain good microscopy results of viable trophozoites.
Idiopathic Internal Thoracic Artery (ITA) Pseudoaneurysm treated with Endovascular Embolization

Wong WJ, Leong BDK, Mak CH

Med J Malaysia, 2017 04;72(2):144-146.
PMID: 28473685 MyJurnal

A 44-year-old female was diagnosed with an ITA pseudoaneurysm in the right supraclavicular fossa. She was successfully treated with endovascular embolization. The challenges of diagnosis and treatment are discussed.
Fulltext Implementation and Operational Research: Effects of CD4 Monitoring Frequency on Clinical End Points in Clinically Stable HIV-Infected Patients With Viral Suppression

Ahn JY, Boettiger D, Law M, Kumarasamy N, Yunihastuti E, Chaiwarith R, et al.

J Acquir Immune Defic Syndr, 2015 Jul 01;69(3):e85-92.
PMID: 25850606 DOI: 10.1097/QAI.0000000000000634

BACKGROUND: Current treatment guidelines for HIV infection recommend routine CD4 lymphocyte (CD4) count monitoring in patients with viral suppression. This may have a limited impact on influencing care as clinically meaningful CD4 decline rarely occurs during viral suppression.
METHODS: In a regional HIV observational cohort in the Asia-Pacific region, patients with viral suppression (2 consecutive viral loads <400 copies/mL) and a CD4 count ≥200 cells per microliter who had CD4 testing 6 monthly were analyzed. Main study end points were occurrence of 1 CD4 count <200 cells per microliter (single CD4 <200) and 2 CD4 counts <200 cells per microliter within a 6-month period (confirmed CD4 <200). A comparison of time with single and confirmed CD4 <200 with biannual or annual CD4 assessment was performed by generating a hypothetical group comprising the same patients with annual CD4 testing by removing every second CD4 count.
RESULTS: Among 1538 patients, the rate of single CD4 <200 was 3.45/100 patient-years and of confirmed CD4 <200 was 0.77/100 patient-years. During 5 years of viral suppression, patients with baseline CD4 200-249 cells per microliter were significantly more likely to experience confirmed CD4 <200 compared with patients with higher baseline CD4 [hazard ratio, 55.47 (95% confidence interval: 7.36 to 418.20), P < 0.001 versus baseline CD4 ≥500 cells/μL]. Cumulative probabilities of confirmed CD4 <200 was also higher in patients with baseline CD4 200-249 cells per microliter compared with patients with higher baseline CD4. There was no significant difference in time to confirmed CD4 <200 between biannual and annual CD4 measurement (P = 0.336).
CONCLUSIONS: Annual CD4 monitoring in virally suppressed HIV patients with a baseline CD4 ≥250 cells per microliter may be sufficient for clinical management.
Fulltext Isobolographic analysis of the hypnotic interaction between propofol and thiopental

Wong, W. H., Lim, T. A., Lim, K. Y.

Malaysian Journal of Medicine and Health Sciences, 2010;6(1):83-89.
MyJurnal

Introduction: Giving two intravenous anaesthetic agents simultaneously generally results in an additive effect. The aim of this study was to investigate the interaction between propofol and thiopental when given to patients who have had sedative premedication. Methods: Fifty patients were admitted into the study. All patients received oral midazolam 3.75 mg and intravenous fentanyl 100 mg before induction of anaesthesia. Twenty patients received an infusion of either propofol or thiopental while 30 patients received an infusion of an admixture of both drugs. Isobolographic analysis was used to determine the interaction between the two drugs. Results: The interaction between propofol and thiopental was
additive. The average dose at loss of the eyelash reflex for propofol and thiopental was 0.71 mg kg-1 and 1.54 mg kg-1 respectively. Premedication decreased the induction dose by 38.2%. Conclusion: Propofol and thiopental interact in an additive fashion when given at induction of anaesthesia.
Larval development of the pedunculate barnacles Octolasmis angulata Aurivillius 1894 and Octolasmis cor Aurivillius 1892 (Cirripedia: Thoracica: Poecilasmatidae) from the gills of the mud crab, Scylla tranquebarica Fabricius, 1798

Yap FC, Wong WL, Maule AG, Brennan GP, Lim LH

Arthropod Struct Dev, 2015 May;44(3):253-79.
PMID: 25770075 DOI: 10.1016/j.asd.2015.02.001

Detailed studies of larval development of Octolasmis angulata and Octolasmis cor are pivotal in understanding the larval morphological evolution as well as enhancing the functional ecology. Six planktotrophic naupliar stages and one non-feeding cyprid stage are documented in details for the first time for the two species of Octolasmis. Morphologically, the larvae of O. angulata and O. cor are similar in body size, setation patterns on the naupliar appendages, labrum, dorsal setae-pores, frontal horns, cyprid carapace, fronto-lateral gland pores, and lattice organs. Numbers of peculiarities were observed on the gnathobases of the antennae and mandible throughout the naupliar life-cycle. The setation pattern on the naupliar appendages are classified based on the segmentation on the naupliar appendages. The nauplius VI of both species undergoes a conspicuous change before metamorphosis into cyprid stage. The cyprid structures begin to form and modify beneath the naupliar body towards the end of stage VI. This study emphasises the importance of the pedunculate barnacle larval developmental studies not only to comprehend the larval morphological evolution but also to fill in the gaps in understanding the modification of the naupliar structures to adapt into the cyprid life-style.
Fulltext Late Presentation into Care of HIV Disease and Its Associated Factors in Asia: Results of TAHOD

Jeong SJ, Italiano C, Chaiwarith R, Ng OT, Vanar S, Jiamsakul A, et al.

AIDS Res Hum Retroviruses, 2016 Mar;32(3):255-61.
PMID: 26414065 DOI: 10.1089/AID.2015.0058

Many HIV-infected individuals do not enter health care until late in the infection course. Despite encouraging earlier testing, this situation has continued for several years. We investigated the prevalence of late presenters and factors associated with late presentation among HIV-infected patients in an Asian regional cohort. This cohort study included HIV-infected patients with their first positive HIV test during 2003-2012 and CD4 count and clinical status data within 3 months of that test. Factors associated with late presentation into care (CD4 count <200 cells/μl or an AIDS-defining event within ±3 months of first positive HIV test) were analyzed in a random effects logistic regression model. Among 3,744 patients, 2,681 (72%) were late presenters. In the multivariable model, older patients were more likely to be late presenters than younger (≤30 years) patients [31-40, 41-50, and ≥51 years: odds ratio (OR) = 1.57, 95% confidence interval (CI) 1.31-1.88; OR = 2.01, 95% CI 1.58-2.56; and OR = 1.69, 95% CI 1.23-2.31, respectively; all p ≤ 0.001]. Injecting drug users (IDU) were more likely (OR = 2.15, 95% CI 1.42-3.27, p < 0.001) and those with homosexual HIV exposure were less likely (OR = 0.45, 95% CI 0.35-0.58, p < 0.001) to be late presenters compared to those with heterosexual HIV exposure. Females were less likely to be late presenters (OR = 0.44, 95% CI 0.36-0.53, p < 0.001). The year of first positive HIV test was not associated with late presentation. Efforts to reduce the patients who first seek HIV care at the late stage are needed. The identified risk factors associated with late presentation should be utilized in formulating targeted public health intervention to improve earlier entry into HIV care.
Long-term loss to follow-up in the TREAT Asia HIV Observational Database (TAHOD)

Jiamsakul A, Kiertiburanakul S, Ng OT, Chaiwarith R, Wong W, Ditangco R, et al.

HIV Med, 2019 08;20(7):439-449.
PMID: 30980495 DOI: 10.1111/hiv.12734

OBJECTIVES: With earlier antiretroviral therapy (ART) initiation, time spent in HIV care is expected to increase. We aimed to investigate loss to follow-up (LTFU) in Asian patients who remained in care 5 years after ART initiation.
METHODS: Long-term LTFU was defined as LTFU occurring after 5 years on ART. LTFU was defined as (1) patients not seen in the previous 12 months; and (2) patients not seen in the previous 6 months. Factors associated with LTFU were analysed using competing risk regression.
RESULTS: Under the 12-month definition, the LTFU rate was 2.0 per 100 person-years (PY) [95% confidence interval (CI) 1.8-2.2 among 4889 patients included in the study. LTFU was associated with age > 50 years [sub-hazard ratio (SHR) 1.64; 95% CI 1.17-2.31] compared with 31-40 years, viral load ≥ 1000 copies/mL (SHR 1.86; 95% CI 1.16-2.97) compared with viral load < 1000 copies/mL, and hepatitis C coinfection (SHR 1.48; 95% CI 1.06-2.05). LTFU was less likely to occur in females, in individuals with higher CD4 counts, in those with self-reported adherence ≥ 95%, and in those living in high-income countries. The 6-month LTFU definition produced an incidence rate of 3.2 per 100 PY (95% CI 2.9-3.4 and had similar associations but with greater risks of LTFU for ART initiation in later years (2006-2009: SHR 2.38; 95% CI 1.93-2.94; and 2010-2011: SHR 4.26; 95% CI 3.17-5.73) compared with 2003-2005.
CONCLUSIONS: The long-term LTFU rate in our cohort was low, with older age being associated with LTFU. The increased risk of LTFU with later years of ART initiation in the 6-month analysis, but not the 12-month analysis, implies that there was a possible move towards longer HIV clinic scheduling in Asia.
Low Breast Conserving Surgery (BCS) rates in public hospitals in Malaysia: The effect of stage and ethnicity

Wong WJ, Mosiun JA, Hidayati Z, Balkis R, Sharif SZ, Lee D, et al.

Breast, 2019 Aug;46:136-143.
PMID: 31176055 DOI: 10.1016/j.breast.2019.05.016

INTRODUCTION: Breast-conserving surgery (BCS) with radiation therapy is the procedure of choice for early-stage breast cancer. Survival and locoregional recurrence is non-inferior to mastectomy, with superior cosmetic and psycho-social outcomes. Differing health systems have demonstrated a wide variation in the rate of BCS. Little is known about the rate of BCS and factors influencing its practice in middle resource countries. This study aims to examine the BCS rates in Malaysia and to identify factors influencing its uptake.
METHODOLOGY: This is a multi-centre, cross-sectional study involving the University of Malaya Medical Centre (UMMC), Queen Elizabeth II Hospital (QEH), and Tengku Ampuan Rahimah Hospital (TARH). Patients diagnosed with invasive breast cancer from January 2014 to December 2015 were included, excluding stromal cancers and lymphomas. Univariate and multivariate analyses identified factors influencing BCS.
RESULTS: A total of 1005 patients were diagnosed with breast cancer in the allocated time frame. Excluding incomplete records and those who did not have surgery, 730 patients were analysed. Overall BCS rate was 32.9%. The BCS rate was highest at QEH (54.1%), followed by UMMC (29.5%), and TARH (17.4%). 16.9% had BCS after neoadjuvant therapy. Factors influencing BCS uptake included age, ethnic group, breast-surgeon led services, AJCC Stage, tumour size, HER-2 expression, and tumour grade.
CONCLUSIONS: The rate of BCS in Malaysia is low. A wide variation of rate exists among the studied hospitals. Younger age, earlier AJCC stage, and the presence of a Breast sub-specialist surgeon, would make it more likely that the patient has her breast conserved.
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.
Measurement of the Dependence of the Hadron Production Fraction Ratios f_{s}/f_{u} and f_{d}/f_{u} on B Meson Kinematic Variables in Proton-Proton Collisions at sqrt[s]=13 TeV

Tumasyan A, Adam W, Andrejkovic JW, Bergauer T, Chatterjee S, Damanakis K, et al.

Phys Rev Lett, 2023 Sep 22;131(12):121901.
PMID: 37802954 DOI: 10.1103/PhysRevLett.131.121901

The dependence of the ratio between the B_{s}^{0} and B^{+} hadron production fractions, f_{s}/f_{u}, on the transverse momentum (p_{T}) and rapidity of the B mesons is studied using the decay channels B_{s}^{0}→J/ψϕ and B^{+}→J/ψK^{+}. The analysis uses a data sample of proton-proton collisions at a center-of-mass energy of 13 TeV, collected by the CMS experiment in 2018 and corresponding to an integrated luminosity of 61.6 fb^{-1}. The f_{s}/f_{u} ratio is observed to depend on the B p_{T} and to be consistent with becoming asymptotically constant at large p_{T}. No rapidity dependence is observed. The ratio of the B^{0} to B^{+} meson production fractions, f_{d}/f_{u}, is also measured, for the first time in proton-proton collisions, using the B^{0}→J/ψK^{*0} decay channel. The result is found to be within 1 standard deviation of unity and independent of p_{T} and rapidity, as expected from isospin invariance.
Fulltext Measurement of the Higgs boson production rate in association with top quarks in final states with electrons, muons, and hadronically decaying tau leptons at s = 13 TeV

Sirunyan AM, Tumasyan A, Adam W, Bergauer T, Dragicevic M, Erö J, et al.

Eur Phys J C Part Fields, 2021;81(4):378.
PMID: 34727142 DOI: 10.1140/epjc/s10052-021-09014-x

The rate for Higgs ( H ) bosons production in association with either one ( t H ) or two ( t t ¯ H ) top quarks is measured in final states containing multiple electrons, muons, or tau leptons decaying to hadrons and a neutrino, using proton-proton collisions recorded at a center-of-mass energy of 13 TeV by the CMS experiment. The analyzed data correspond to an integrated luminosity of 137 fb - 1 . The analysis is aimed at events that contain H → W W , H → τ τ , or H → Z Z decays and each of the top quark(s) decays either to lepton+jets or all-jet channels. Sensitivity to signal is maximized by including ten signatures in the analysis, depending on the lepton multiplicity. The separation among t H , t t ¯ H , and the backgrounds is enhanced through machine-learning techniques and matrix-element methods. The measured production rates for the t t ¯ H and t H signals correspond to 0.92 ± 0.19 (stat) - 0.13 + 0.17 (syst) and 5.7 ± 2.7 (stat) ± 3.0 (syst) of their respective standard model (SM) expectations. The corresponding observed (expected) significance amounts to 4.7 (5.2) standard deviations for t t ¯ H , and to 1.4 (0.3) for t H production. Assuming that the Higgs boson coupling to the tau lepton is equal in strength to its expectation in the SM, the coupling y t of the Higgs boson to the top quark divided by its SM expectation, κ t = y t / y t SM , is constrained to be within - 0.9 < κ t < - 0.7 or 0.7 < κ t < 1.1 , at 95% confidence level. This result is the most sensitive measurement of the t t ¯ H production rate to date.
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.
Measurement of the mass dependence of the transverse momentum of lepton pairs in Drell-Yan production in proton-proton collisions at s=13TeV

Tumasyan A, Adam W, Andrejkovic JW, Bergauer T, Chatterjee S, Dragicevic M, et al.

Eur Phys J C Part Fields, 2023;83(7):628.
PMID: 37471210 DOI: 10.1140/epjc/s10052-023-11631-7

The double differential cross sections of the Drell-Yan lepton pair (ℓ+ℓ-, dielectron or dimuon) production are measured as functions of the invariant mass mℓℓ, transverse momentum pT(ℓℓ), and φη∗. The φη∗ observable, derived from angular measurements of the leptons and highly correlated with pT(ℓℓ), is used to probe the low-pT(ℓℓ) region in a complementary way. Dilepton masses up to 1TeV are investigated. Additionally, a measurement is performed requiring at least one jet in the final state. To benefit from partial cancellation of the systematic uncertainty, the ratios of the differential cross sections for various mℓℓ ranges to those in the Z mass peak interval are presented. The collected data correspond to an integrated luminosity of 36.3fb-1 of proton-proton collisions recorded with the CMS detector at the LHC at a centre-of-mass energy of 13TeV. Measurements are compared with predictions based on perturbative quantum chromodynamics, including soft-gluon resummation.
Measurement of the top quark mass using a profile likelihood approach with the lepton + jets final states in proton-proton collisions at s=13TeV

Tumasyan A, Adam W, Andrejkovic JW, Bergauer T, Chatterjee S, Damanakis K, et al.

Eur Phys J C Part Fields, 2023;83(10):963.
PMID: 37906635 DOI: 10.1140/epjc/s10052-023-12050-4

The mass of the top quark is measured in 36.3fb-1 of LHC proton-proton collision data collected with the CMS detector at s=13TeV. The measurement uses a sample of top quark pair candidate events containing one isolated electron or muon and at least four jets in the final state. For each event, the mass is reconstructed from a kinematic fit of the decay products to a top quark pair hypothesis. A profile likelihood method is applied using up to four observables per event to extract the top quark mass. The top quark mass is measured to be 171.77±0.37GeV. This approach significantly improves the precision over previous measurements.
Fulltext Measurements of angular distance and momentum ratio distributions in three-jet and Z + two-jet final states in pp collisions

Sirunyan AM, Tumasyan A, Adam W, Bergauer T, Dragicevic M, Erö J, et al.

Eur Phys J C Part Fields, 2021;81(9):852.
PMID: 34727147 DOI: 10.1140/epjc/s10052-021-09570-2

Collinear (small-angle) and large-angle, as well as soft and hard radiations are investigated in three-jet and Z + two-jet events collected in proton-proton collisions at the LHC. The normalized production cross sections are measured as a function of the ratio of transverse momenta of two jets and their angular separation. The measurements in the three-jet and Z + two-jet events are based on data collected at a center-of-mass energy of 8 TeV , corresponding to an integrated luminosity of 19.8 fb - 1 . The Z + two-jet events are reconstructed in the dimuon decay channel of the Z boson. The three-jet measurement is extended to include s = 13 TeV data corresponding to an integrated luminosity of 2.3 fb - 1 . The results are compared to predictions from event generators that include parton showers, multiple parton interactions, and hadronization. The collinear and soft regions are in general well described by parton showers, whereas the regions of large angular separation are often best described by calculations using higher-order matrix elements.
Fulltext Measurements of p p → Z Z production cross sections and constraints on anomalous triple gauge couplings at s = 13 TeV

Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Bergauer T, Dragicevic M, et al.

Eur Phys J C Part Fields, 2021;81(3):200.
PMID: 33750993 DOI: 10.1140/epjc/s10052-020-08817-8

The production of Z boson pairs in proton-proton ( p p ) collisions, p p → ( Z / γ ∗ ) ( Z / γ ∗ ) → 2 ℓ 2 ℓ ' , where ℓ , ℓ ' = e or μ , is studied at a center-of-mass energy of 13 TeV with the CMS detector at the CERN LHC. The data sample corresponds to an integrated luminosity of 137 fb - 1 , collected during 2016-2018. The Z Z production cross section, σ tot ( p p → Z Z ) = 17.4 ± 0.3 (stat) ± 0.5 (syst) ± 0.4 (theo) ± 0.3 (lumi) pb , measured for events with two pairs of opposite-sign, same-flavor leptons produced in the mass region 60 < m ℓ + ℓ - < 120 GeV is consistent with standard model predictions. Differential cross sections are also measured and agree with theoretical predictions. The invariant mass distribution of the four-lepton system is used to set limits on anomalous Z Z Z and Z Z γ couplings.
Fulltext Measurements of production cross sections of the Higgs boson in the four-lepton final state in proton-proton collisions at s = 13 TeV

CMS Collaboration, Sirunyan AM, Tumasyan A, Adam W, Andrejkovic JW, Bergauer T, et al.

Eur Phys J C Part Fields, 2021;81(6):488.
PMID: 34727143 DOI: 10.1140/epjc/s10052-021-09200-x

Production cross sections of the Higgs boson are measured in the H → Z Z → 4 ℓ ( ℓ = e , μ ) decay channel. A data sample of proton-proton collisions at a center-of-mass energy of 13 TeV , collected by the CMS detector at the LHC and corresponding to an integrated luminosity of 137 fb - 1 is used. The signal strength modifier μ , defined as the ratio of the Higgs boson production rate in the 4 ℓ channel to the standard model (SM) expectation, is measured to be μ = 0.94 ± 0.07 (stat) - 0.08 + 0.09 (syst) at a fixed value of m H = 125.38 GeV . The signal strength modifiers for the individual Higgs boson production modes are also reported. The inclusive fiducial cross section for the H → 4 ℓ process is measured to be 2 . 84 - 0.22 + 0.23 (stat) - 0.21 + 0.26 (syst) fb , which is compatible with the SM prediction of 2.84 ± 0.15 fb for the same fiducial region. Differential cross sections as a function of the transverse momentum and rapidity of the Higgs boson, the number of associated jets, and the transverse momentum of the leading associated jet are measured. A new set of cross section measurements in mutually exclusive categories targeted to identify production mechanisms and kinematical features of the events is presented. The results are in agreement with the SM predictions.
Measurements of the Electroweak Diboson Production Cross Sections in Proton-Proton Collisions at sqrt[s]=5.02 TeV Using Leptonic Decays

Tumasyan A, Adam W, Andrejkovic JW, Bergauer T, Chatterjee S, Dragicevic M, et al.

Phys Rev Lett, 2021 Nov 05;127(19):191801.
PMID: 34797136 DOI: 10.1103/PhysRevLett.127.191801

The first measurements of diboson production cross sections in proton-proton interactions at a center-of-mass energy of 5.02 TeV are reported. They are based on data collected with the CMS detector at the LHC, corresponding to an integrated luminosity of 302 pb^{-1}. Events with two, three, or four charged light leptons (electrons or muons) in the final state are analyzed. The WW, WZ, and ZZ total cross sections are measured as σ_{WW}=37.0_{-5.2}^{+5.5}(stat)_{-2.6}^{+2.7}(syst) pb, σ_{WZ}=6.4_{-2.1}^{+2.5}(stat)_{-0.3}^{+0.5}(syst) pb, and σ_{ZZ}=5.3_{-2.1}^{+2.5}(stat)_{-0.4}^{+0.5}(syst) pb. All measurements are in good agreement with theoretical calculations at combined next-to-next-to-leading order quantum chromodynamics and next-to-leading order electroweak accuracy.

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