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  1. Rapid Thermochromic and Highly Thermally Conductive Nanocomposite Based on Silicone Rubber for Temperature Visualization Thermal Management in Electronic Devices
    Yan J, Cai Y, Zhang H, Han M, Liu X, Chen H, et al.
    ACS Appl Mater Interfaces, 2024 Feb 14;16(6):7883-7893.
    PMID: 38299449 DOI: 10.1021/acsami.3c17947
    Effective heat dissipation and real-time temperature monitoring are crucial for ensuring the long-term stable operation of modern, high-performance electronic products. This study proposes a silicon rubber polydimethylsiloxane (PDMS)-based nanocomposite with a rapid thermal response and high thermal conductivity. This nanocomposite enables both rapid heat dissipation and real-time temperature monitoring for high-performance electronic products. The reported material primarily consists of a thermally conductive layer (Al2O3/PDMS composites) and a reversible thermochromic layer (organic thermochromic material, graphene oxide, and PDMS nanocoating; OTM-GO/PDMS). The thermal conductivity of OTM-GO/Al2O3/PDMS nanocomposites reached 4.14 W m-1 K-1, reflecting an increase of 2200% relative to that of pure PDMS. When the operating temperature reached 35, 45, and 65 °C, the surface of OTM-GO/Al2O3/PDMS nanocomposites turned green, yellow, and red, respectively, and the thermal response time was only 30 s. The OTM-GO/Al2O3/PDMS nanocomposites also exhibited outstanding repeatability and maintained excellent color stability over 20 repeated applications.
  2. Blood-based dynamic genomic signature for obsessive-compulsive disorder
    Wang Y, Cheng C, Zhang Z, Wang J, Wang Y, Li X, et al.
    Am J Med Genet B Neuropsychiatr Genet, 2018 12;177(8):709-716.
    PMID: 30350918 DOI: 10.1002/ajmg.b.32675
    No biologically based diagnostic criteria are in clinical use today for obsessive-compulsive disorder (OCD), schizophrenia, and major depressive disorder (MDD), which are defined with reference to Diagnostic and Statistical Manual clinical symptoms alone. However, these disorders cannot always be well distinguished on clinical grounds and may also be comorbid. A biological blood-based dynamic genomic signature that can differentiate among OCD, MDD, and schizophrenia would therefore be of great utility. This study enrolled 77 patients with OCD, 67 controls with no psychiatric illness, 39 patients with MDD, and 40 with schizophrenia. An OCD-specific gene signature was identified using blood gene expression analysis to construct a predictive model of OCD that can differentiate this disorder from healthy controls, MDD, and schizophrenia using a logistic regression algorithm. To verify that the genes selected were not derived as a result of chance, the algorithm was tested twice. First, the algorithm was used to predict the cohort with true disease/control status and second, the algorithm predicted the cohort with disease/control status randomly reassigned (null set). A six-gene panel (COPS7A, FKBP1A, FIBP, TP73-AS1, SDF4, and GOLGA8A) discriminated patients with OCD from healthy controls, MDD, and schizophrenia in the training set (with an area under the receiver-operating-characteristic curve of 0.938; accuracy, 86%; sensitivity, 88%; and specificity, 85%). Our findings indicate that a blood transcriptomic signature can distinguish OCD from healthy controls, MDD, and schizophrenia. This finding further confirms the feasibility of using dynamic blood-based genomic signatures in psychiatric disorders and may provide a useful tool for clinical staff engaged in OCD diagnosis and decision making.
  3. Biomimetic self-assembly of lipase-zeolitic imidazolate frameworks with enhanced biosensing of protox inhibiting herbicides
    Cheng C, Shen C, Lai OM, Tan CP, Cheong LZ
    Anal Methods, 2021 Nov 04;13(42):4974-4984.
    PMID: 34661208 DOI: 10.1039/d1ay01307f
    Protox inhibiting herbicides such as nitrofen have detrimental effects on the environment and human health. The current work aims to fabricate a Candida rugosa lipase (CRL)-based electrochemical sensor for rapid and sensitive detection of protox inhibiting herbicides (nitrofen). We proposed the use of poly(vinylpyrrolidone) (PVP) and amino-acids to promote accumulation of Zn2+ ions at the surfaces of Candida rugosa lipase (CRL) and subsequently induce self-assembly of a CRL-zeolitic imidazolate framework (ZIF) structure. This process can be easily and rapidly achieved via a one-pot facile self-assembly method. Steady-state fluorescence spectroscopy indicated that CRL has undergone a conformational change following encapsulation within the ZIF structure. This conformational change is beneficial as the prepared PVP/Glu/CRL@ZIF-8 exhibited enhanced catalytic activity (207% of native CRL), and higher substrate affinity (lower Km than native CRL) and showed high stability under harsh denaturing conditions. PVP/Glu/CRL@ZIF-8 was finally used for electrochemical biosensing of nitrofen. The fabricated biosensor has a wide linear detection range (0-100 μM), a lower limit of detection and a good recovery rate.
  4. Sun exposure and the risk of prostate cancer in the Singapore Prostate Cancer Study: a case-control study
    Chia SE, Wong KY, Cheng C, Lau W, Tan PH
    Asian Pac J Cancer Prev, 2012;13(7):3179-85.
    PMID: 22994730
    BACKGROUND: Most of the epidemiology studies on the effects of sun exposure and prostate cancer were conducted among the temperate countries of North America and Europe. Little is known about the influence on Asian populations. The purpose of current study was to evaluate any association of sun exposure with risk of prostate cancer in Chinese, Malays and Indians who reside in the tropics.

    METHODS: The Singapore Prostate Cancer Study is a hospital-based case-control study of 240 prostate cancer incident cases and 268 controls conducted in Singapore between April 2007 and May 2009. Detailed information on outdoor activities in the sun, skin colour, sun sensitivity and other possible risk factors were collected in personal interviews. Cases were further classified by Gleason scores and TNM staging. Odds ratios (OR) and 95% confidence intervals (CI) were calculated using unconditional logistic regression analysis, adjusted for age, ethnicity, education, family history of any cancers, BMI and skin colour.

    RESULTS: We found that prostate cancer risk was increased in subjects with black/dark-brown eyes (OR 5.88, 95%CI 3.17-10.9), darker skin colour e.g. tan/dark brown/black (OR 7.62, 95%CI 3.41-17.0), frequent sunburn in lifetime (OR 4.30, 95%CI 1.7-11.2) and increased general sun exposure in adulthood per week (OR 2.03, 95%CI 1.09-3.81). The increased risk was consistent for high grade tumours and advanced stage prostate cancers.

    CONCLUSION: The findings from this study suggest that excessive sun exposure is a risk factor for prostate cancer in Asians.

  5. Fulltext Prostate-specific antigen levels among Chinese, Malays and Indians in Singapore from a community-based study
    Chia SE, Lau WK, Cheng C, Chin CM, Tan J, Ho SH
    Asian Pac J Cancer Prev, 2007 Jul-Sep;8(3):375-8.
    PMID: 18159971
    The purpose of this study was to examine the distribution of prostate-specific antigen levels among Chinese, Malays and Indians in Singapore, taking the effect of age into consideration. The study was carried out as part of the Singapore Prostate Awareness Week from 23-26th February 2004. Men above 50 years old went to four government-restructured hospitals to participate in the study. Participants filled up a questionnaire and provided 5 ml of blood for measurement of PSA levels using the Abbott IMx Total PSA assay (Abbott Laboratories). 3,486 men responded to the study, comprising 92.8% Chinese, 3.0% Malays, 2.5% Indians and 1.8% Others. 92.7% of them had PSA levels of 4 microg/L or less. There were no significant differences (p<0.05) between the mean PSA levels of Chinese (1.60 microg/L), Malays (1.39 microg/L), Indians (1.23 microg/L) and Others (1.70 microg/L). PSA levels were significantly associated with age (Spearman's r= 0.27, p<0.01). PSA levels increased with each 10-year age group and these trends were significant (p<0.0001) across both PSA group levels and age groupings. In the 50-60 years age groups, the prevalence of PSA levels >4 mug/L were 1.1% and 3.7% respectively. This rose rapidly to 11.3% and 23.5% for age groups >60-70 and >80 years respectively. Our study shows that the median PSA levels in the Caucasian population in the USA are higher than those of Chinese, Malays and Indians in Singapore. PSA levels were positively associated with age. It may be more appropriate to offer PSA testing to men who are >60 years old rather than the current >50 years.
  6. Fulltext Electroencephalographic changes associated with antinociceptive actions of lidocaine, ketamine, meloxicam, and morphine administration in minimally anaesthetized dogs
    Kaka U, Hui Cheng C, Meng GY, Fakurazi S, Kaka A, Behan AA, et al.
    Biomed Res Int, 2015;2015:305367.
    PMID: 25695060 DOI: 10.1155/2015/305367
    Effects of ketamine and lidocaine on electroencephalographic (EEG) changes were evaluated in minimally anaesthetized dogs, subjected to electric stimulus. Six dogs were subjected to six treatments in a crossover design with a washout period of one week. Dogs were subjected to intravenous boluses of lidocaine 2 mg/kg, ketamine 3 mg/kg, meloxicam 0.2 mg/kg, morphine 0.2 mg/kg and loading doses of lidocaine 2 mg/kg followed by continuous rate infusion (CRI) of 50 and 100 mcg/kg/min, and ketamine 3 mg/kg followed by CRI of 10 and 50 mcg/kg/min. Electroencephalogram was recorded during electrical stimulation prior to any drug treatment (before treatment) and during electrical stimulation following treatment with the drugs (after treatment) under anaesthesia. Anaesthesia was induced with propofol and maintained with halothane at a stable concentration between 0.85 and 0.95%. Pretreatment median frequency was evidently increased (P < 0.05) for all treatment groups. Lidocaine, ketamine, and morphine depressed the median frequency resulting from the posttreatment stimulation. The depression of median frequency suggested evident antinociceptive effects of these treatments in dogs. It is therefore concluded that lidocaine and ketamine can be used in the analgesic protocol for the postoperative pain management in dogs.
  7. Fulltext Carcinoma of stomach detected by routine transabdominal ultrasound
    Wong M, Shum S, Chau W, Cheng C
    Biomed Imaging Interv J, 2010 10 01;6(4):e39.
    PMID: 21611075 DOI: 10.2349/biij.6.4.e39
    Assessment of the stomach is not commonly included in routine scanning protocol of upper abdominal ultrasound (USG). However, assessment of the stomach in patients presenting with epigastric pain can yield invaluable results. This paper presents, as an illustration, a case of carcinoma of stomach detected by transabdominal ultrasound. The diagnosis is confirmed by subsequent CT, upper endoscopy and operation.
  8. Current perspectives, future challenges and key technologies of biohydrogen production for building a carbon-neutral future: A review
    Tasnim Sahrin N, Shiong Khoo K, Wei Lim J, Shamsuddin R, Musa Ardo F, Rawindran H, et al.
    Bioresour Technol, 2022 Nov;364:128088.
    PMID: 36216282 DOI: 10.1016/j.biortech.2022.128088
    The ever-increasing quantity of greenhouse gases in the atmosphere can be attributed to the rapid increase in the world population as well as the expansion of globalization. Hence, achieving carbon neutrality by 2050 stands as a challenging task to accomplish. Global industrialization had necessitated the need to enhance the current production systems to reduce greenhouse gases emission, whilst promoting the capture of carbon dioxide from atmosphere. Hydrogen is often touted as the fuel of future via substituting fossil-based fuels. In this regard, renewable hydrogen happens to be a niche sector of novel technologies in achieving carbon neutrality. Microalgae-based biohydrogen technologies could be a sustainable and economical approach to produce hydrogen from a renewable source, while simultaneously promoting the absorption of carbon dioxide. This review highlights the current perspectives of biohydrogen production as an alternate source of energy. In addition, future challenges associated with biohydrogen production at large-scale application, storage and transportation are included. Key technologies in producing biohydrogen are finally described in building a carbon-neutral future.
  9. Progress and Advances in Porous Silica-based Scaffolds for Enhanced Solid-state Hydrogen Storage: A Systematic Literature Review
    Abdulkadir BA, Jalil AA, Cheng CK, Setiabudi HD
    Chem Asian J, 2024 Jan 15;19(2):e202300833.
    PMID: 37997488 DOI: 10.1002/asia.202300833
    Hydrogen plays a crucial role in the future energy landscape owing to its high energy density. However, finding an ideal storage material is the key challenge to the success of the hydrogen economy. Various solid-state hydrogen storage materials, such as metal hydrides, have been developed to realize safe, effective, and compact hydrogen storage. However, low kinetics and thermodynamic stability lead to a high working temperature and a low hydrogen sorption rate of the metal hydrides. Using scaffolds made from porous materials like silica to confine the metal hydrides is necessary for better and improved hydrogen storage. Therefore, this article reviews porous silica-based scaffolds as an ideal material for improved hydrogen storage. The outcome showed that confining the metal hydrides using scaffolds based on porous silica significantly increases their storage capacities. It was also found that the structural modifications of the silica-based scaffold into a hollow structure further improved the storage capacity and increased the affinity and confinement ability of the metal hydrides, which prevents the agglomeration of metal particles during the adsorption/desorption process. Hence, the structural modifications of the silica material into a fibrous and hollow material are recommended to be crucial for further enhancing the metal hydride storage capacity.
  10. Epidemiology of internet behaviors and addiction among adolescents in six Asian countries
    Mak KK, Lai CM, Watanabe H, Kim DI, Bahar N, Ramos M, et al.
    Cyberpsychol Behav Soc Netw, 2014 Nov;17(11):720-8.
    PMID: 25405785 DOI: 10.1089/cyber.2014.0139
    Internet addiction has become a serious behavioral health problem in Asia. However, there are no up-to-date country comparisons. The Asian Adolescent Risk Behavior Survey (AARBS) screens and compares the prevalence of Internet behaviors and addiction in adolescents in six Asian countries. A total of 5,366 adolescents aged 12-18 years were recruited from six Asian countries: China, Hong Kong, Japan, South Korea, Malaysia, and the Philippines. Participants completed a structured questionnaire on their Internet use in the 2012-2013 school year. Internet addiction was assessed using the Internet Addiction Test (IAT) and the Revised Chen Internet Addiction Scale (CIAS-R). The variations in Internet behaviors and addiction across countries were examined. The overall prevalence of smartphone ownership is 62%, ranging from 41% in China to 84% in South Korea. Moreover, participation in online gaming ranges from 11% in China to 39% in Japan. Hong Kong has the highest number of adolescents reporting daily or above Internet use (68%). Internet addiction is highest in the Philippines, according to both the IAT (5%) and the CIAS-R (21%). Internet addictive behavior is common among adolescents in Asian countries. Problematic Internet use is prevalent and characterized by risky cyberbehaviors.
  11. Measurement Invariance of the Internet Addiction Test Among Hong Kong, Japanese, and Malaysian Adolescents
    Lai CM, Mak KK, Cheng C, Watanabe H, Nomachi S, Bahar N, et al.
    Cyberpsychol Behav Soc Netw, 2015 Oct;18(10):609-17.
    PMID: 26468915 DOI: 10.1089/cyber.2015.0069
    There has been increased research examining the psychometric properties on the Internet Addiction Test (IAT) in different populations. This population-based study examined the psychometric properties and measurement invariance of the IAT in adolescents from three Asian countries. In the Asian Adolescent Risk Behavior Survey (AARBS), 2,535 secondary school students (55.9% girls) aged 12-18 years from Hong Kong (n=844), Japan (n=744), and Malaysia (n=947) completed a survey in 2012-2013 school year. A nested hierarchy of hypotheses concerning the IAT cross-country invariance was tested using multigroup confirmatory factor analyses. Replicating past findings in Hong Kong adolescents, the construct of the IAT is best represented by a second-order three-factor structure in Malaysian and Japanese adolescents. Configural, metric, scalar, and partial strict factorial invariance was established across the three samples. No cross-country differences on Internet addiction were detected at the latent mean level. This study provided empirical support for the IAT as a reliable and factorially stable instrument, and valid to be used across Asian adolescent populations.
  12. Analysis of surface water area dynamics and driving forces in the Bosten Lake basin based on GEE and SEM for the period 2000 to 2021
    Li X, Zhang F, Shi J, Chan NW, Cai Y, Cheng C, et al.
    Environ Sci Pollut Res Int, 2024 Feb;31(6):9333-9346.
    PMID: 38191729 DOI: 10.1007/s11356-023-31702-2
    As an inland dryland lake basin, the rivers and lakes within the Lake Bosten basin provide scarce but valuable water resources for a fragile environment and play a vital role in the development and sustainability of the local societies. Based on the Google Earth Engine (GEE) platform, combined with the geographic information system (GIS) and remote sensing (RS) technology, we used the index WI2019 to extract and analyze the water body area changes of the Bosten Lake basin from 2000 to 2021 when the threshold value is -0.25 and the slope mask is 8°. The driving factors of water body area changes were also analyzed using the partial least squares-structural equation model (PLS-SEM). The result shows that in the last 20 years, the area of water bodies in the Bosten Lake basin generally fluctuated during the dry, wet, and permanent seasons, with a decreasing trend from 2000 to 2015 and an increasing trend between 2015 and 2019 followed by a steadily decreasing trend afterward. The main driver of the change in wet season water bodies in the Bosten Lake basin is the climatic factors, with anthropogenic factors having a greater influence on the water body area of dry season and permanent season than that of wet season. Our study achieved an accurate and convenient extraction of water body area and drivers, providing up-to-date information to fully understand the spatial and temporal variation of surface water body area and its drivers in the basin, which can be used to effectively manage water resources.
  13. Fulltext Association of Genetic Ancestry With the Molecular Subtypes and Prognosis of Childhood Acute Lymphoblastic Leukemia
    Lee SHR, Antillon-Klussmann F, Pei D, Yang W, Roberts KG, Li Z, et al.
    JAMA Oncol, 2022 Mar 01;8(3):354-363.
    PMID: 35084434 DOI: 10.1001/jamaoncol.2021.6826
    IMPORTANCE: Racial and ethnic disparities persist in the incidence and treatment outcomes of childhood acute lymphoblastic leukemia (ALL). However, there is a paucity of data describing the genetic basis of these disparities, especially in association with modern ALL molecular taxonomy and in the context of contemporary treatment regimens.

    OBJECTIVE: To evaluate the association of genetic ancestry with childhood ALL molecular subtypes and outcomes of modern ALL therapy.

    DESIGN, SETTING, AND PARTICIPANTS: This multinational, multicenter genetic association study was conducted from March 1, 2000, to November 20, 2020, among 2428 children and adolescents with ALL enrolled in frontline trials from the United States, South East Asia (Singapore and Malaysia), and Latin America (Guatemala), representing diverse populations of European, African, Native American, East Asian, and South Asian descent. Statistical analysis was conducted from February 3, 2020, to April 19, 2021.

    MAIN OUTCOMES AND MEASURES: Molecular subtypes of ALL and genetic ancestry were comprehensively characterized by performing RNA sequencing. Associations of genetic ancestries with ALL molecular subtypes and treatment outcomes were then evaluated.

    RESULTS: Among the participants in the study, 1340 of 2318 (57.8%) were male, and the mean (SD) age was 7.8 (5.3) years. Of 21 ALL subtypes identified, 8 were associated with ancestry. East Asian ancestry was positively associated with the frequency of somatic DUX4 (odds ratio [OR], 1.30 [95% CI, 1.16-1.45]; P 

  14. Contributions of climate change and human activities to grassland degradation and improvement from 2001 to 2020 in Zhaosu County, China
    Zhang M, Zhang F, Guo L, Dong P, Cheng C, Kumar P, et al.
    J Environ Manage, 2023 Dec 15;348:119465.
    PMID: 37924697 DOI: 10.1016/j.jenvman.2023.119465
    Grassland degradation poses a serious threat to biodiversity, ecosystem services, and human well-being. In this study, we investigated grassland degradation in Zhaosu County, China, between 2001 and 2020, and analyzed the impacts of climate change and human activities using the Miami model. The actual net primary productivity (ANPP) obtained with CASA (Carnegie-Ames-Stanford Approach) modeling, showed a decreasing trend, reflecting the significant degradation that the grasslands in Zhaosu County have experienced in the past 20 years. Grassland degradation was found to be highest in 2018, while the degraded area continuously decreased in the last 3 years (2018-2020). Climatic factors for found to be the dominant factor affecting grassland degradation, particularly the decrease in precipitation. On the other hand, human activities were found to be the main factor affecting improvement of grasslands, especially in recent years. This finding profoundly elucidates the underlying causes of grassland degradation and improvement and helps implement ecological conservation and restoration measures. From a practical perspective, the research results provide an important reference for the formulation of policies and management strategies for sustainable land use.
  15. Remote sensing for chromophoric dissolved organic matter (CDOM) monitoring research 2003-2022: A bibliometric analysis based on the web of science core database
    Li Z, Zhang F, Shi J, Chan NW, Tan ML, Kung HT, et al.
    Mar Pollut Bull, 2023 Nov;196:115653.
    PMID: 37879130 DOI: 10.1016/j.marpolbul.2023.115653
    Chromophoric dissolved organic matter (CDOM) occupies a critical part in biogeochemistry and energy flux of aquatic ecosystems. CDOM research spans in many fields, including chemistry, marine environment, biomass cycling, physics, hydrology, and climate change. In recent years, a series of remarkable research milestone have been achieved. On the basis of reviewing the research process of CDOM, combined with a bibliometric analysis, this study aims to provide a comprehensive review of the development and applications of remote sensing in monitoring CDOM from 2003 to 2022. The findings show that remote sensing data plays an important role in CDOM research as proven with the increasing number of publications since 2003, particularly in China and the United States. Primary research areas have gradually changed from studying absorption and fluorescence properties to optimization of remote sensing inversion models in recent years. Since the composition of oceanic and freshwater bodies differs significantly, it is important to choose the appropriate inversion method for different types of water body. At present, the monitoring of CDOM mainly relies on a single sensor, but the fusion of images from different sensors can be considered a major research direction due to the complex characteristics of CDOM. Therefore, in the future, the characteristics of CDOM will be studied in depth inn combination with multi-source data and other application models, where inversion algorithms will be optimized, inversion algorithms with low dependence on measured data will be developed, and a transportable inversion model will be built to break the regional limitations of the model and to promote the development of CDOM research in a deeper and more comprehensive direction.
  16. Automated extraction of retinal vasculature
    Tan JH, Acharya UR, Chua KC, Cheng C, Laude A
    Med Phys, 2016 May;43(5):2311.
    PMID: 27147343 DOI: 10.1118/1.4945413
    The authors propose an algorithm that automatically extracts retinal vasculature and provides a simple measure to correct the extraction. The output of the method is a network of salient points, and blood vessels are drawn by connecting the salient points using a centripetal parameterized Catmull-Rom spline.
  17. First Evidence for cos2β>0 and Resolution of the Cabibbo-Kobayashi-Maskawa Quark-Mixing Unitarity Triangle Ambiguity
    Adachi I, Adye T, Ahmed H, Ahn JK, Aihara H, Akar S, et al.
    Phys Rev Lett, 2018 Dec 28;121(26):261801.
    PMID: 30636113 DOI: 10.1103/PhysRevLett.121.261801
    We present first evidence that the cosine of the CP-violating weak phase 2β is positive, and hence exclude trigonometric multifold solutions of the Cabibbo-Kobayashi-Maskawa (CKM) Unitarity Triangle using a time-dependent Dalitz plot analysis of B^{0}→D^{(*)}h^{0} with D→K_{S}^{0}π^{+}π^{-} decays, where h^{0}∈{π^{0},η,ω} denotes a light unflavored and neutral hadron. The measurement is performed combining the final data sets of the BABAR and Belle experiments collected at the ϒ(4S) resonance at the asymmetric-energy B factories PEP-II at SLAC and KEKB at KEK, respectively. The data samples contain (471±3)×10^{6}BB[over ¯] pairs recorded by the BABAR detector and (772±11)×10^{6}BB[over ¯] pairs recorded by the Belle detector. The results of the measurement are sin2β=0.80±0.14(stat)±0.06(syst)±0.03(model) and cos2β=0.91±0.22(stat)±0.09(syst)±0.07(model). The result for the direct measurement of the angle β of the CKM Unitarity Triangle is β=[22.5±4.4(stat)±1.2(syst)±0.6(model)]°. The measurement assumes no direct CP violation in B^{0}→D^{(*)}h^{0} decays. The quoted model uncertainties are due to the composition of the D^{0}→K_{S}^{0}π^{+}π^{-} decay amplitude model, which is newly established by performing a Dalitz plot amplitude analysis using a high-statistics e^{+}e^{-}→cc[over ¯] data sample. CP violation is observed in B^{0}→D^{(*)}h^{0} decays at the level of 5.1 standard deviations. The significance for cos2β>0 is 3.7 standard deviations. The trigonometric multifold solution π/2-β=(68.1±0.7)° is excluded at the level of 7.3 standard deviations. The measurement resolves an ambiguity in the determination of the apex of the CKM Unitarity Triangle.
  18. 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^{-}.
  19. 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.
  20. Search for Long-Lived Particles Decaying in the CMS End Cap Muon Detectors in Proton-Proton Collisions at sqrt[s]=13  TeV
    Tumasyan A, Adam W, Andrejkovic JW, Bergauer T, Chatterjee S, Dragicevic M, et al.
    Phys Rev Lett, 2021 Dec 24;127(26):261804.
    PMID: 35029469 DOI: 10.1103/PhysRevLett.127.261804
    A search for long-lived particles (LLPs) produced in decays of standard model (SM) Higgs bosons is presented. The data sample consists of 137  fb^{-1} of proton-proton collisions at sqrt[s]=13  TeV, recorded at the LHC in 2016-2018. A novel technique is employed to reconstruct decays of LLPs in the end cap muon detectors. The search is sensitive to a broad range of LLP decay modes and to masses as low as a few GeV. No excess of events above the SM background is observed. The most stringent limits to date on the branching fraction of the Higgs boson to LLPs subsequently decaying to quarks and τ^{+}τ^{-} are found for proper decay lengths greater than 6, 20, and 40 m, for LLP masses of 7, 15, and 40 GeV, respectively.
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