Displaying publications 101 - 120 of 268 in total

Abstract:
Sort:
  1. Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Asilar E, Bergauer T, et al.
    Eur Phys J C Part Fields, 2016;76(6):317.
    PMID: 28775662 DOI: 10.1140/epjc/s10052-016-4149-y
    A search for narrow resonances decaying to an electron and a muon is presented. The [Formula: see text] [Formula: see text] mass spectrum is also investigated for non-resonant contributions from the production of quantum black holes (QBHs). The analysis is performed using data corresponding to an integrated luminosity of 19.7[Formula: see text] collected in proton-proton collisions at a centre-of-mass energy of 8[Formula: see text] with the CMS detector at the LHC. With no evidence for physics beyond the standard model in the invariant mass spectrum of selected [Formula: see text] pairs, upper limits are set at 95 [Formula: see text] confidence level on the product of cross section and branching fraction for signals arising in theories with charged lepton flavour violation. In the search for narrow resonances, the resonant production of a [Formula: see text] sneutrino in R-parity violating supersymmetry is considered. The [Formula: see text] sneutrino is excluded for masses below 1.28[Formula: see text] for couplings [Formula: see text], and below 2.30[Formula: see text] for [Formula: see text] and [Formula: see text]. These are the most stringent limits to date from direct searches at high-energy colliders. In addition, the resonance searches are interpreted in terms of a model with heavy partners of the [Formula: see text] boson and the photon. In a framework of TeV-scale quantum gravity based on a renormalization of Newton's constant, the search for non-resonant contributions to the [Formula: see text] [Formula: see text] mass spectrum excludes QBH production below a threshold mass [Formula: see text] of 1.99[Formula: see text]. In models that invoke extra dimensions, the bounds range from 2.36[Formula: see text] for one extra dimension to 3.63[Formula: see text] for six extra dimensions. This is the first search for QBHs decaying into the [Formula: see text] [Formula: see text] final state.
  2. Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Asilar E, Bergauer T, et al.
    Eur Phys J C Part Fields, 2016;76(7):371.
    PMID: 28280444 DOI: 10.1140/epjc/s10052-016-4206-6
    A search is presented for narrow heavy resonances X decaying into pairs of Higgs bosons ([Formula: see text]) in proton-proton collisions collected by the CMS experiment at the LHC at [Formula: see text]. The data correspond to an integrated luminosity of 19.7[Formula: see text]. The search considers [Formula: see text] resonances with masses between 1 and 3[Formula: see text], having final states of two b quark pairs. Each Higgs boson is produced with large momentum, and the hadronization products of the pair of b quarks can usually be reconstructed as single large jets. The background from multijet and [Formula: see text] events is significantly reduced by applying requirements related to the flavor of the jet, its mass, and its substructure. The signal would be identified as a peak on top of the dijet invariant mass spectrum of the remaining background events. No evidence is observed for such a signal. Upper limits obtained at 95 % confidence level for the product of the production cross section and branching fraction [Formula: see text] range from 10 to 1.5[Formula: see text] for the mass of X from 1.15 to 2.0[Formula: see text], significantly extending previous searches. For a warped extra dimension theory with a mass scale [Formula: see text] [Formula: see text], the data exclude radion scalar masses between 1.15 and 1.55[Formula: see text].
  3. 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.
  4. Sirunyan AM, Tumasyan A, Adam W, Bergauer T, Dragicevic M, Erö J, et al.
    Eur Phys J C Part Fields, 2021;81(8):688.
    PMID: 34780582 DOI: 10.1140/epjc/s10052-021-09348-6
    A search is presented for a heavy vector resonance decaying into a Z boson and the standard model Higgs boson, where the Z boson is identified through its leptonic decays to electrons, muons, or neutrinos, and the Higgs boson is identified through its hadronic decays. The search is performed in a Lorentz-boosted regime and is based on data collected from 2016 to 2018 at the CERN LHC, corresponding to an integrated luminosity of 137 fb - 1 . Upper limits are derived on the production of a narrow heavy resonance Z ' , and a mass below 3.5 and 3.7 Te is excluded at 95% confidence level in models where the heavy vector boson couples predominantly to fermions and to bosons, respectively. These are the most stringent limits placed on the Heavy Vector Triplet Z ' model to date. If the heavy vector boson couples exclusively to standard model bosons, upper limits on the product of the cross section and branching fraction are set between 23 and 0.3 fb for a Z ' mass between 0.8 and 4.6 Te , respectively. This is the first limit set on a heavy vector boson coupling exclusively to standard model bosons in its production and decay.
  5. Sirunyan AM, Tumasyan A, Adam W, Andrejkovic JW, Bergauer T, Chatterjee S, et al.
    Eur Phys J C Part Fields, 2021;81(8):723.
    PMID: 34780581 DOI: 10.1140/epjc/s10052-021-09472-3
    A search for charged Higgs bosons produced in vector boson fusion processes and decaying into vector bosons, using proton-proton collisions at s = 13 TeV at the LHC, is reported. The data sample corresponds to an integrated luminosity of 137 fb - 1 collected with the CMS detector. Events are selected by requiring two or three electrons or muons, moderate missing transverse momentum, and two jets with a large rapidity separation and a large dijet mass. No excess of events with respect to the standard model background predictions is observed. Model independent upper limits at 95% confidence level are reported on the product of the cross section and branching fraction for vector boson fusion production of charged Higgs bosons as a function of mass, from 200 to 3000 GeV . The results are interpreted in the context of the Georgi-Machacek model.
  6. Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Bergauer T, Brandstetter J, et al.
    PMID: 31976987 DOI: 10.1140/epjc/s10052-019-7493-x
    Two related searches for phenomena beyond the standard model (BSM) are performed using events with hadronic jets and significant transverse momentum imbalance. The results are based on a sample of proton-proton collisions at a center-of-mass energy of 13 Te , collected by the CMS experiment at the LHC in 2016-2018 and corresponding to an integrated luminosity of 137 fb - 1 . The first search is inclusive, based on signal regions defined by the hadronic energy in the event, the jet multiplicity, the number of jets identified as originating from bottom quarks, and the value of the kinematic variable M T 2 for events with at least two jets. For events with exactly one jet, the transverse momentum of the jet is used instead. The second search looks in addition for disappearing tracks produced by BSM long-lived charged particles that decay within the volume of the tracking detector. No excess event yield is observed above the predicted standard model background. This is used to constrain a range of BSM models that predict the following: the pair production of gluinos and squarks in the context of supersymmetry models conserving R-parity, with or without intermediate long-lived charginos produced in the decay chain; the resonant production of a colored scalar state decaying to a massive Dirac fermion and a quark; or the pair production of scalar and vector leptoquarks each decaying to a neutrino and a top, bottom, or light-flavor quark. In most of the cases, the results obtained are the most stringent constraints to date.
  7. Soh EB, Lim JM
    Aust N Z J Obstet Gynaecol, 1999 Aug;39(3):389-90.
    PMID: 10554965
    This is a rare case of antepartum haemorrhage arising from the nonpregnant uterus in a woman with uterine didelphys. The bleeding and subsequent passage of a decidual cast did not have any adverse effect on the ongoing pregnancy.
  8. Lim JM, Soh EB, Raman S
    Aust N Z J Obstet Gynaecol, 1995 Feb;35(1):54-5.
    PMID: 7772001
    Misoprostol seems to be a drug with many potential uses apart from the treatment of gastric and duodenal ulcers. The oral tablet appears to be effective for termination of midtrimester pregnancy when administered intravaginally. Further research should be carried out to determine its full range of action in order that the drug can be utilized to its maximum potential.
  9. Ng TK, Hassan K, Lim JB, Lye MS, Ishak R
    Am J Clin Nutr, 1991 04;53(4 Suppl):1015S-1020S.
    PMID: 2012009 DOI: 10.1093/ajcn/53.4.1015S
    The effects on serum lipids of diets prepared with palm olein, corn oil, and coconut oil supplying approximately 75% of the fat calories were compared in three matched groups of healthy volunteers (61 males, 22 females, aged 20-34 y). Group I received a coconut-palm-coconut dietary sequence; group II, coconut-corn-coconut; and group III, coconut oil during all three 5-wk dietary periods. Compared with entry-level values, coconut oil raised the serum total cholesterol concentration greater than 10% in all three groups. Subsequent feeding of palm olein or corn oil significantly reduced the total cholesterol (-19%, -36%), the LDL cholesterol (-20%, -42%%) and the HDL cholesterol (-20%, -26%) concentrations, respectively. Whereas the entry level of the ratio of LDL to HDL was not appreciably altered by coconut oil, this ratio was decreased 8% by palm olein and 25% by corn oil. Serum triglycerides were unaffected during the palm-olein period but were significantly reduced during the corn-oil period.
  10. Leong SS, Ahmad Z, Lim J
    Soft Matter, 2015 Oct 14;11(38):7696.
    PMID: 26365252 DOI: 10.1039/c5sm90159f
    Correction for 'Magnetophoresis of superparamagnetic nanoparticles at low field gradient: hydrodynamic effect' by Sim Siong Leong et al., Soft Matter, 2015, 11, 6968-6980.
  11. Leong SS, Ahmad Z, Lim J
    Soft Matter, 2015 Sep 21;11(35):6968-80.
    PMID: 26234726 DOI: 10.1039/c5sm01422k
    Convective current driven by momentum transfer between magnetic nanoparticles (MNPs) and their surrounding fluid during magnetophoresis process under a low gradient magnetic field (<100 T m(-1)) is presented. This magnetophoresis induced convective flow, which imposed direct hydrodynamic effects onto the separation kinetics of the MNPs under low gradient magnetic separation (LGMS), is analogous to the natural convection found in heat transportation. Herein, we show the significance of the induced convection in controlling the transport behavior of MNPs, even at a very low particle concentration of 5 mg L(-1), and this feature can be characterized by the newly defined magnetic Grashof number. By incorporating fluid flow equations into the existing magnetophoresis model, we reveal two unique features of this convective flow associated with low gradient magnetophoresis, namely, (1) the continuous homogenization of the MNPs solution and (2) accompanying sweeping flow that accelerates the collection of MNPs. According to both simulation and experimental data, the induced convection boosts the magnetophoretic capture of MNPs by approximately 30 times compared to the situation with no convection.
  12. Loke MF, Ng CG, Vilashni Y, Lim J, Ho B
    Sci Rep, 2016 05 25;6:26784.
    PMID: 27222005 DOI: 10.1038/srep26784
    Helicobacter pylori may reside in the human stomach as two morphological forms: the culturable spiral form and the viable but non-culturable (VBNC) coccoid form. This bacterium transforms from spiral to coccoid under in vitro suboptimal conditions. However, both spiral and coccoid have demonstrated its infectivity in laboratory animals, suggesting that coccoid may potentially be involved in the transmission of H. pylori. To determine the relevance of the coccoid form in viability and infectivity, we compared the protein profiles of H. pylori coccoids obtained from prolonged (3-month-old) culture with that of 3-day-old spirals of two H. pylori standard strains using SWATH (Sequential Window Acquisition of all Theoretical mass spectra)-based approach. The protein profiles reveal that the coccoids retained basal level of metabolic proteins and also high level of proteins that participate in DNA replication, cell division and biosynthesis demonstrating that coccoids are viable. Most interestingly, these data also indicate that the H. pylori coccoids possess higher level of proteins that are involved in virulence and carcinogenesis than their spiral counterparts. Taken together, these findings have important implications in the understanding on the pathogenesis of H. pylori-induced gastroduodenal diseases, as well as the probable transmission mode of this bacterium.
  13. Mohd-Zahid MH, Zulkifli SN, Che Abdullah CA, Lim J, Fakurazi S, Wong KK, et al.
    RSC Adv, 2021 Apr 26;11(26):16131-16141.
    PMID: 35481195 DOI: 10.1039/d1ra01093j
    The enhanced permeability and retention effect allows for passive targeting of solid tumours by nanoparticles carrying anticancer drugs. However, active targeting by incorporation of various ligands onto nanoparticles can provide for a more selective and enhanced chemotherapeutic effect and complement the deficiencies of the passive targeting approach. Here we report on the design of the carboxyl-terminated PEGylated gold nanoparticles (AuNPs), their functionalization with anti-CD133 monoclonal antibody (mAb) via a crosslinking reaction, and subsequent 5-fluorouracil (5-FU) drug loading. The synthesized products in the form of stable colloids were characterised using a range of physicochemical techniques, including X-ray diffraction (XRD), UV-Vis spectroscopy, transmission electron microscopy (TEM), and dynamic light scattering (DLS). Conjugation of anti-CD133 mAb onto PEGylated AuNPs was confirmed with the use of UV-Vis, BCA protein assay and fluorescence microscopy. HCT116 colorectal cancer cells abundantly expressed CD133: 92.4 ± 1.3%, as measured by flow cytometry. Whereas PEGylated AuNPs not conjugated with anti-CD133 mAb accumulated mainly at the cellular membrane, nanoparticles conjugated with anti-CD133 mAb were contained within the nuclear region of the cells. Anti-CD133 mAb conjugation facilitated the specific intracellular uptake due to specific antigen-antibody binding interaction. In vitro cytotoxicity studies on HCT116 cells showed that PEGylated AuNPs and PEGylated AuNPs-CD133 did not elicit any toxicity at any of the tested concentrations. Meanwhile, 5-FU-PEGylated AuNPs-CD133 significantly reduced the cell viability relative to the treatment with 5-FU-PEGylated AuNPs without anti-CD133 mAb conjugates (p < 0.0001). This study shows that the conjugation of nanocarriers with the anti-CD133 antibody improves the specific targeting of 5-FU against colorectal cancer cells. These results demonstrate that simultaneous functionalisation of PEGylated AuNPs with antibodies and chemotherapeutic drugs is a viable strategy to combat cancer through targeted drug delivery.
  14. Lojanapiwat B, Lee JY, Gang Z, Kim CS, Fai NC, Hakim L, et al.
    Prostate Int, 2019 Jun;7(2):60-67.
    PMID: 31384607 DOI: 10.1016/j.prnil.2018.06.001
    The Asian Prostate Cancer (A-CaP) study is an Asia-wide initiative that was launched in December 2015 in Tokyo, Japan, with the objective of surveying information about patients who have received a histopathological diagnosis of prostate cancer (PCa) and are undergoing treatment and clarifying distribution of staging, the actual status of treatment choices, and treatment outcomes. The study aims to clarify the clinical situation for PCa in Asia and use the outcomes for the purposes of international comparison. Following the first meeting in Tokyo in December 2015, the second A-CaP meeting was held in Seoul, Korea, in September 2016. This, the third A-CaP meeting, was held on October 14, 2017, in Chiang Mai, Thailand, with the participation of members and collaborators from 12 countries and regions. In the meeting, participating countries and regions presented the current status of data collection, and the A-CaP office presented a preliminary analysis of the registered cases received from each country and region. Participants discussed ongoing challenges relating to data input and collection, institutional, and legislative issues that may present barriers to data sharing, and the outlook for further patient registrations through to the end of the registration period in December 2018. In addition to A-CaP-specific discussions, a series of special lectures were also delivered on the situation for health insurance in the United States, the correlation between insurance coverage and PCa outcomes, and the outlook for robotic surgery in the Asia-Pacific region. Members also confirmed the principles of authorship in collaborative studies, with a view to publishing original articles based on A-CaP data in the future.
  15. Kim CS, Lee JY, Chung BH, Kim WJ, Fai NC, Hakim L, et al.
    Prostate Int, 2017 Sep;5(3):95-103.
    PMID: 28828352 DOI: 10.1016/j.prnil.2017.03.006
    The Asian Prostate Cancer (A-CaP) Study is an Asia-wide initiative that has been developed over the course of 2 years. The study was launched in December 2015 in Tokyo, Japan, and the participating countries and regions engaged in preparations for the study during the course of 2016, including patient registration and creation of databases for the purpose of the study. The Second A-CaP Meeting was held on September 8, 2016 in Seoul, Korea, with the participation of members and collaborators from 12 countries and regions. Under the study, each participating country or region will begin registration of newly diagnosed prostate cancer patients and conduct prognostic investigations. From the data gathered, common research themes will be identified, such as comparisons among Asian countries of background factors in newly diagnosed prostate cancer patients. This is the first Asia-wide study of prostate cancer and has developed from single country research efforts in this field, including in Japan and Korea. At the Second Meeting, participating countries and regions discussed the status of preparations and discussed various issues that are being faced. These issues include technical challenges in creating databases, promoting participation in each country or region, clarifying issues relating to data input, addressing institutional issues such as institutional review board requirements, and the need for dedicated data managers. The meeting was positioned as an opportunity to share information and address outstanding issues prior to the initiation of the study. In addition to A-CaP-specific discussions, a series of special lectures was also delivered as a means of providing international perspectives on the latest developments in prostate cancer and the use of databases and registration studies around the world.
  16. Leong KW, Teh A, Bosco JJ, Lim J
    Postgrad Med J, 1995 Oct;71(840):625-7.
    PMID: 8545293
    Pregnancy following idiopathic aplastic anaemia is rare and is difficult to manage because of life-threatening episodes of bleeding and infections. Only a handful of cases has been reported in the literature. The pregnancies were unsuccessful in the majority. The present report describes a patient with moderately severe idiopathic aplastic anaemia who was managed with intensive haematological support leading to delivery of a healthy infant by caesarean section. Despite platelet transfusion refractoriness as a result of transfusions prior to pregnancy, adequate platelet transfusions prevented excessive bleeding. The literature is reviewed and management with platelet transfusions is discussed.
  17. Lim J, Bhoo-Pathy N, Sothilingam S, Malek R, Sundram M, Hisham Bahadzor B, et al.
    PLoS One, 2014;9(8):e104917.
    PMID: 25111507 DOI: 10.1371/journal.pone.0104917
    OBJECTIVES: To study the baseline PSA profile and determine the factors influencing the PSA levels within a multiethnic Asian setting.
    MATERIALS AND METHODS: We conducted a cross-sectional study of 1054 men with no clinical evidence of prostate cancer, prostate surgery or 5α-reductase inhibitor treatment of known prostate conditions. The serum PSA concentration of each subject was assayed. Potential factors associated with PSA level including age, ethnicity, height, weight, family history of prostate cancer, lower urinary tract voiding symptoms (LUTS), prostate volume and digital rectal examination (DRE) were evaluated using univariable and multivariable analysis.
    RESULTS: There were 38 men (3.6%) found to have a PSA level above 4 ng/ml and 1016 (96.4%) with a healthy PSA (≤4 ng/ml). The median PSA level of Malay, Chinese and Indian men was 1.00 ng/ml, 1.16 ng/ml and 0.83 ng/ml, respectively. Indians had a relatively lower median PSA level and prostate volume than Malays and Chinese, who shared a comparable median PSA value across all 10-years age groups. The PSA density was fairly similar amongst all ethnicities. Further analysis showed that ethnicity, weight and prostate volume were independent factors associated with age specific PSA level in the multivariable analysis (p<0.05).
    CONCLUSION: These findings support the concept that the baseline PSA level varies between different ethnicities across all age groups. In addition to age and prostate volume, ethnicity may also need to be taken into account when investigating serum PSA concentrations in the multiethnic Asian population.
  18. Lim J, Bhoo-Pathy N, Sothilingam S, Malek R, Sundram M, Tan GH, et al.
    PLoS One, 2015;10(6):e0130820.
    PMID: 26098884 DOI: 10.1371/journal.pone.0130820
    To determine the lower urinary tract symptoms (LUTS) profile and factors affecting its degree of severity including cardiovascular risk profile, age, ethnicity, education level and prostate volume in a multiethnic Asian setting.
  19. Padmanabhan H, Hassan NT, Wong SW, Lee YQ, Lim J, Hasan SN, et al.
    PLoS One, 2022;17(2):e0263675.
    PMID: 35167615 DOI: 10.1371/journal.pone.0263675
    There is an increasing number of cancer patients undertaking treatment-focused genetic testing despite not having a strong family history or high a priori risk of being carriers because of the decreasing cost of genetic testing and development of new therapies. There are limited studies on the psychosocial outcome of a positive result among breast cancer patients who are at low a priori risk, particularly in women of Asian descent. Breast cancer patients enrolled under the Malaysian Breast Cancer Genetic Study between October 2002 and February 2018 were tested for BRCA1, BRCA2 and PALB2 genes. All 104 carriers identified were invited by a research genetic counsellor for result disclosure. Of the 104 carriers, 64% (N = 66) had low a priori risk as determined by PENN II scores. Psychosocial, risk perception and health behaviour measures survey were conducted at baseline (pre-result disclosure), and at two to six weeks after result disclosure. At baseline, younger carriers with high a priori risk had higher Cancer Worry Scale scores than those with low a priori risk but all scores were within acceptable range. Around 75% and 55% of high a priori risk carriers as well as 80% and 67% of low a priori risk carriers had problems in the "living with cancer" and "children" psychosocial domains respectively. All carriers regardless of their a priori risk demonstrated an improved risk perception that also positively influenced their intent to undergo risk management procedures. This study has shown that with sufficient counselling and support, low a priori risk carriers are able to cope psychologically, have improved perceived risk and increased intent for positive health behaviour despite having less anticipation from a family history prior to knowing their germline carrier status.
  20. Sirunyan AM, Tumasyan A, Adam W, Asilar E, Bergauer T, Brandstetter J, et al.
    Phys Rev Lett, 2018 Apr 06;120(14):142301.
    PMID: 29694144 DOI: 10.1103/PhysRevLett.120.142301
    The relative yields of ϒ mesons produced in pp and Pb-Pb collisions at sqrt[s_{NN}]=5.02  TeV and reconstructed via the dimuon decay channel are measured using data collected by the CMS experiment. Double ratios are formed by comparing the yields of the excited states, ϒ(2S) and ϒ(3S), to the ground state, ϒ(1S), in both Pb-Pb and pp collisions at the same center-of-mass energy. The double ratios, [ϒ(nS)/ϒ(1S)]_{Pb-Pb}/[ϒ(nS)/ϒ(1S)]_{pp}, are measured to be 0.308±0.055(stat)±0.019(syst) for the ϒ(2S) and less than 0.26 at 95% confidence level for the ϒ(3S). No significant ϒ(3S) signal is found in the Pb-Pb data. The double ratios are studied as a function of collision centrality, as well as ϒ transverse momentum and rapidity. No significant dependencies are observed.
Filters
Contact Us

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links