Displaying publications 21 - 40 of 120 in total

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  1. Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Bergauer T, Dragicevic M, et al.
    Phys Rev Lett, 2015 Feb 13;114(6):061801.
    PMID: 25723204
    A search for new long-lived particles decaying to leptons is presented using proton-proton collisions produced by the LHC at √[s]=8  TeV. Data used for the analysis were collected by the CMS detector and correspond to an integrated luminosity of 19.7  fb(-1). Events are selected with an electron and muon with opposite charges that both have transverse impact parameter values between 0.02 and 2 cm. The search has been designed to be sensitive to a wide range of models with nonprompt e-μ final states. Limits are set on the "displaced supersymmetry" model, with pair production of top squarks decaying into an e-μ final state via R-parity-violating interactions. The results are the most restrictive to date on this model, with the most stringent limit being obtained for a top squark lifetime corresponding to cτ=2  cm, excluding masses below 790 GeV at 95% confidence level.
    Matched MeSH terms: Protons
  2. Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Bergauer T, Dragicevic M, et al.
    Phys Rev Lett, 2015 Mar 13;114(10):101801.
    PMID: 25815923
    Results are presented from a search for new decaying massive particles whose presence is inferred from an imbalance in transverse momentum and which are produced in association with a single top quark that decays into a bottom quark and two light quarks. The measurement is performed using 19.7  fb^{-1} of data from proton-proton collisions at a center-of-mass energy of 8 TeV, collected with the CMS detector at the CERN LHC. No deviations from the standard model predictions are observed and lower limits are set on the masses of new invisible bosons. In particular, scalar and vector particles, with masses below 330 and 650 GeV, respectively, are excluded at 95% confidence level, thereby substantially extending a previous limit published by the CDF Collaboration.
    Matched MeSH terms: Protons
  3. Oh AL, Tan AG, Phan HS, Lee BC, Jumaat N, Chew SP, et al.
    Pharm Pract (Granada), 2015 Apr-Jun;13(3):633.
    PMID: 26445624 DOI: 10.18549/PharmPract.2015.03.633
    Proton-pump inhibitors (PPI) and histamine-2 receptor antagonists (H2RA) are common acid suppressants used in gastrointestinal disorders. The trend of usage in Malaysia has changed from predominantly H2RA to PPI from 2007 to 2008, 3.46 versus 2.87 and 2.99 versus 3.24 DDD (Defined Daily Dose)/1000 population/day respectively. This raises concerns as PPI overutilization amounts to higher cost expenditure and are associated with various untoward consequences such as Clostridium difficile-associated diarrhea, pneumonia, and osteoporosis.
    Matched MeSH terms: Protons
  4. Perumal, V., Khoo, W.C., Abdul-Hamid, A., Ismail, A., Saari, K., Murugesu, S., et al.
    MyJurnal
    Momordica charantia, also known as bitter melon or ‘peria katak’ in Malaysia, is a member of the family Cucurbitaceae. Bitter melon is an excellent source of vitamins and minerals that made it extensively nutritious. Moreover, the seed, fruit and leave of the plant contain bioactive compounds with a wide range of biological activities that have been used in traditional medicines in the treatment of several diseases, including inflammation, infections, obesity and diabetes. The aim of this study was to evaluate changes in urinary metabolite profile of the normal, streptozotocin-induced type 1 diabetes and M. charantia treated diabetic rats using proton nuclear magnetic resonance (1H-NMR) -based metabolomics profiling. Study had been carried out by inducing diabetes in the rats through injection of streptozotocin, which exhibited type 1 diabetes. M. charantia extract (100 and 200 mg/kg body weight) was administrated to the streptozotocin-induced diabetic rats for one week. Blood glucose level after administration was measured to examine hypoglycemic effect of the extract. The results obtained indicated that M. charantia was effective in lowering blood glucose level of the diabetic rats. The loading plot of Partial Least Square (PLS) component 1 showed that diabetic rats had increased levels of lactate and glucose in urine whereas normal and the extract treated diabetic rats had higher levels of succinate, creatine, creatinine, urea and phenylacetylglycine in urine. While the loading plot of PLS component 2 showed a higher levels of succinate, citrate, creatine, creatinine, sugars, and hippurate in urine of normal rat compared to the extract treated diabetic rat. Administration of M. charantia extract was found to be able to regulate the altered metabolic processes. Thus, it could be potentially used to treat the diabetic patients.
    
    Matched MeSH terms: Protons
  5. Xu J, Cheng KK, Yang Z, Wang C, Shen G, Wang Y, et al.
    PMID: 26170882 DOI: 10.1155/2015/801691
    Gastric mucosal lesion (GML) is a common gastrointestinal disorder with multiple pathogenic mechanisms in clinical practice. In traditional Chinese medicine (TCM), electroacupuncture (EA) treatment has been proven as an effective therapy for GML, although the underlying healing mechanism is not yet clear. Here, we used proton nuclear magnetic resonance- ((1)H NMR-) based metabolomic method to investigate the metabolic perturbation induced by GML and the therapeutic effect of EA treatment on stomach meridian (SM) acupoints. Clear metabolic differences were observed between GML and control groups, and related metabolic pathways were discussed by means of online metabolic network analysis toolbox. By comparing the endogenous metabolites from GML and GML-SM groups, the disturbed pathways were partly recovered towards healthy state via EA treated on SM acupoints. Further comparison of the metabolic variations induced by EA stimulated on SM and the control gallbladder meridian (GM) acupoints showed a quite similar metabolite composition except for increased phenylacetylglycine, 3,4-dihydroxymandelate, and meta-hydroxyphenylacetate and decreased N-methylnicotinamide in urine from rats with EA treated on SM acupoints. The current study showed the potential application of metabolomics in providing further insight into the molecular mechanism of acupuncture.
    Matched MeSH terms: Protons
  6. Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Asilar E, Bergauer T, et al.
    Phys Rev Lett, 2016 Jan 22;116(3):032301.
    PMID: 26849587 DOI: 10.1103/PhysRevLett.116.032301
    The production cross sections of the B^{+}, B^{0}, and B_{s}^{0} mesons, and of their charge conjugates, are measured via exclusive hadronic decays in p+Pb collisions at the center-of-mass energy sqrt[s_{NN}]=5.02  TeV with the CMS detector at the CERN LHC. The data set used for this analysis corresponds to an integrated luminosity of 34.6  nb^{-1}. The production cross sections are measured in the transverse momentum range between 10 and 60  GeV/c. No significant modification is observed compared to proton-proton perturbative QCD calculations scaled by the number of incoherent nucleon-nucleon collisions. These results provide a baseline for the study of in-medium b quark energy loss in Pb+Pb collisions.
    Matched MeSH terms: Protons
  7. Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Asilar E, Bergauer T, et al.
    Phys Rev Lett, 2016 Feb 19;116(7):071801.
    PMID: 26943527 DOI: 10.1103/PhysRevLett.116.071801
    A search for narrow resonances in proton-proton collisions at sqrt[s]=13  TeV is presented. The invariant mass distribution of the two leading jets is measured with the CMS detector using a data set corresponding to an integrated luminosity of 2.4  fb^{-1}. The highest observed dijet mass is 6.1 TeV. The distribution is smooth and no evidence for resonant particles is observed. Upper limits at 95% confidence level are set on the production cross section for narrow resonances with masses above 1.5 TeV. When interpreted in the context of specific models, the limits exclude string resonances with masses below 7.0 TeV, scalar diquarks below 6.0 TeV, axigluons and colorons below 5.1 TeV, excited quarks below 5.0 TeV, color-octet scalars below 3.1 TeV, and W^{'} bosons below 2.6 TeV. These results significantly extend previously published limits.
    Matched MeSH terms: Protons
  8. Shahabudin N, Yahya R, Gan SN
    Polymers (Basel), 2016 Apr 06;8(4).
    PMID: 30979216 DOI: 10.3390/polym8040125
    One of the approaches to prolong the service lifespan of polymeric material is the development of self-healing ability by means of embedded microcapsules containing a healing agent. In this work, poly(melamine-urea-formaldehyde) (PMUF) microcapsules containing a palm oil-based alkyd were produced by polymerization of melamine resin, urea and formaldehyde that encapsulated droplets of the suspended alkyd particles. A series of spherical and free-flowing microcapsules were obtained. The chemical properties of core and shell materials were characterized by Attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR) and proton nuclear magnetic resonance spectroscopy (¹H-NMR). Differential scanning calorimetry (DSC) analysis showed a glass transition around -15 °C due to the alkyd, and a melting temperature at around 200 °C due to the shell. Thermogravimetric analysis (TGA) results showed that the core and shell thermally degraded within the temperature range of 200⁻600 °C. Field emission scanning electron microscope (FESEM) examination of the ruptured microcapsule showed smooth inner and rough outer surfaces of the shell. Flexural strength and microhardness (Vickers) of the cured epoxy compound were not affected with the incorporation of 1%⁻3% of the microcapsules. The viability of the healing reactions was demonstrated by blending small amounts of alkyd with epoxy and hardener at different ratios. The blends could readily cure to non-sticky hard solids at room temperature and the reactions could be verified by ATR-FTIR.
    Matched MeSH terms: Protons
  9. Brela MZ, Wójcik MJ, Witek ŁJ, Boczar M, Wrona E, Hashim R, et al.
    J Phys Chem B, 2016 04 28;120(16):3854-62.
    PMID: 27045959 DOI: 10.1021/acs.jpcb.6b01601
    In this study, the proton dynamics of hydrogen bonds for two forms of crystalline aspirin was investigated by the Born-Oppenheimer molecular dynamics (BOMD) method. Analysis of the geometrical parameters of hydrogen bonds using BOMD reveals significant differences in hydrogen bonding between the two crystalline forms of aspirin, Form I and Form II. Analysis of the trajectory for Form I shows spontaneous proton transfer in cyclic dimers, which is absent in Form II. Quantization of the O-H stretching modes allows a detailed discussion on the strength of hydrogen-bonding interactions. The focal point of our study is examination of the hydrogen bond characteristics in the crystal structure and clarification of the influence of hydrogen bonding on the presence of the two crystalline forms of aspirin. In the BOMD method, thermal motions were taken into account. Solving the Schrödinger equation for the snapshots of 2D proton potentials, extracted from MD, gives the best agreement with IR spectra. The character of medium-strong hydrogen bonds in Form I of aspirin was compared with that of weaker hydrogen bonds in aspirin Form II. Two proton minima are present in the potential function for the hydrogen bonds in Form I. The band contours, calculated by using one- and two-dimensional O-H quantization, reflect the differences in the hydrogen bond strengths between the two crystalline forms of aspirin, as well as the strong hydrogen bonding in the cyclic dimers of Form I and the medium-strong hydrogen bonding in Form II.
    Matched MeSH terms: Protons*
  10. Chai MN, Isa MI
    Sci Rep, 2016 Jun 06;6:27328.
    PMID: 27265642 DOI: 10.1038/srep27328
    The plasticized solid bio-polymer electrolytes (SBEs) system has been formed by introducing glycerol (Gly) as the plasticizer into the carboxymethyl cellulose (CMC) doped with oleic acid (OA) via solution casting techniques. The ionic conductivity of the plasticized SBEs has been studied using Electrical Impedance Spectroscopy. The highest conductivity achieved is 1.64 × 10(-4) S cm(-1) for system containing 40 wt. % of glycerol. FTIR deconvolution technique had shown that the conductivity of CMC-OA-Gly SBEs is primarily influenced by the number density of mobile ions. Transference number measurement has shown that the cation diffusion coefficient and ionic mobility is higher than anion which proved the plasticized polymer system is a proton conductor.
    Matched MeSH terms: Protons*
  11. Al-Hardan NH, Abdul Hamid MA, Ahmed NM, Jalar A, Shamsudin R, Othman NK, et al.
    Sensors (Basel), 2016 Jun 07;16(6).
    PMID: 27338381 DOI: 10.3390/s16060839
    In this study, porous silicon (PSi) was prepared and tested as an extended gate field-effect transistor (EGFET) for pH sensing. The prepared PSi has pore sizes in the range of 500 to 750 nm with a depth of approximately 42 µm. The results of testing PSi for hydrogen ion sensing in different pH buffer solutions reveal that the PSi has a sensitivity value of 66 mV/pH that is considered a super Nernstian value. The sensor considers stability to be in the pH range of 2 to 12. The hysteresis values of the prepared PSi sensor were approximately 8.2 and 10.5 mV in the low and high pH loop, respectively. The result of this study reveals a promising application of PSi in the field for detecting hydrogen ions in different solutions.
    Matched MeSH terms: Protons
  12. Kamari A, Aljafree NF, Yusoff SN
    Int J Biol Macromol, 2016 Jul;88:263-72.
    PMID: 27041651 DOI: 10.1016/j.ijbiomac.2016.03.071
    In this study, an amphiphilic chitosan derivative namely N,N-dimethylhexadecyl carboxymethyl chitosan (DCMC) was synthesised and applied for the first time as a carrier agent for rotenone. The physical and chemical properties of DCMC were characterised by using Fourier Transform Infrared Spectrometer (FTIR), Proton Nuclear Magnetic Resonance Spectrometer ((1)H NMR), CHN-O Elemental Analyser, Thermogravimetric Analyser (TGA) and Differential Scanning Calorimeter (DSC). DCMC was soluble in acidic (except pH 4), neutral and basic media with percent of transmittance (%T) values ranged from 67.2 to 99.4%. The critical micelle concentration (CMC) was determined as 0.095mg/mL. Transmission Electron Microscopy (TEM) analysis confirmed that DCMC has formed self-aggregates and exhibited spherical shape with the size of 65.5-137.0nm. The encapsulation efficiency (EE) and loading capacity (LC) of DCMC micelles with different weight ratios (DCMC:rotenone; 5:1, 50:1 and 100:1) were determined by using High Performance Liquid Chromatography (HPLC). The weight ratio of 100:1 gave the best EE with the value of more than 95.0%. DCMC micelles performed an excellent ability to control the release of rotenone, of which 99.0% of rotenone was released within 48h. Overall, DCMC has several key features to be an effective carrier agent for pesticide formulations.
    Matched MeSH terms: Protons
  13. Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Asilar E, Bergauer T, et al.
    Phys Rev Lett, 2016 Jul 15;117(3):031802.
    PMID: 27472109 DOI: 10.1103/PhysRevLett.117.031802
    A search for narrow resonances decaying into dijet final states is performed on data from proton-proton collisions at a center-of-mass energy of 8 TeV, corresponding to an integrated luminosity of 18.8  fb^{-1}. The data were collected with the CMS detector using a novel technique called data scouting, in which the information associated with these selected events is much reduced, permitting collection of larger data samples. This technique enables CMS to record events containing jets at a rate of 1 kHz, by collecting the data from the high-level-trigger system. In this way, the sensitivity to low-mass resonances is increased significantly, allowing previously inaccessible couplings of new resonances to quarks and gluons to be probed. The resulting dijet mass distribution yields no evidence of narrow resonances. Upper limits are presented on the resonance cross sections as a function of mass, and compared with a variety of models predicting narrow resonances. The limits are translated into upper limits on the coupling of a leptophobic resonance Z_{B}^{'} to quarks, improving on the results obtained by previous experiments for the mass range from 500 to 800 GeV.
    Matched MeSH terms: Protons
  14. Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Asilar E, Bergauer T, et al.
    Phys Rev Lett, 2016 Jul 29;117(5):051802.
    PMID: 27517765 DOI: 10.1103/PhysRevLett.117.051802
    A search for the resonant production of high-mass photon pairs is presented. The analysis is based on samples of proton-proton collision data collected by the CMS experiment at center-of-mass energies of 8 and 13 TeV, corresponding to integrated luminosities of 19.7 and 3.3  fb^{-1}, respectively. The interpretation of the search results focuses on spin-0 and spin-2 resonances with masses between 0.5 and 4 TeV and with widths, relative to the mass, between 1.4×10^{-4} and 5.6×10^{-2}. Limits are set on scalar resonances produced through gluon-gluon fusion, and on Randall-Sundrum gravitons. A modest excess of events compatible with a narrow resonance with a mass of about 750 GeV is observed. The local significance of the excess is approximately 3.4 standard deviations. The significance is reduced to 1.6 standard deviations once the effect of searching under multiple signal hypotheses is considered. More data are required to determine the origin of this excess.
    Matched MeSH terms: Protons
  15. Ramlli MA, Isa MI
    J Phys Chem B, 2016 11 10;120(44):11567-11573.
    PMID: 27723333
    Fourier transform infrared (FT-IR), X-ray diffraction (XRD), and transference number measurement (TNM) techniques were applied to investigate the complexation, structural, and ionic transport properties of and the dominant charge-carrier species in a solid biopolymer electrolyte (SBE) system based on carboxymethyl cellulose (CMC) doped with ammonium fluoride (NH4F), which was prepared via a solution casting technique. The SBEs were partially opaque in appearance, with no phase separation. The presence of interactions between the host polymer (CMC) and the ionic dopant (NH4F) was proven by FT-IR analysis at the C-O band. XRD spectra analyzed using Origin 8 software disclose that the degree of crystallinity (χc%) of the SBEs decreased with the addition of NH4F, indicating an increase in the amorphous nature of the SBEs. Analysis of the ionic transport properties reveals that the ionic conductivity of the SBEs is dependent on the ionic mobility (μ) and diffusion of ions (D). TNM analysis confirms that the SBEs are proton conductors.
    Matched MeSH terms: Protons*
  16. Darfizzi Derawi, Jumat Salimon
    Sains Malaysiana, 2016;45:817-823.
    Sebatian hidroksi-eter-POo
    (80% hasil) disintesis melalui pembukaan gelang oksirana minyak sawit olein terepoksida
    (EPOo
    ) secara alkoholisis. Hasil optimum pembukaan gelang oksirana (99.2%) dicapai dengan menggunakan asid
    sulfurik 3% v/bt pada suhu tindak balas yang tinggi (80o
    C) selama 30 minit masa tindak balas. Spektrum resonan
    magnetik nukleus-proton (1
    H-NMR) hidroksi-eter-POo
    telah menunjukkan kehadiran puncak proton pada karbon eter
    (3.2, 3.5 ppm) dan proton pada kumpulan hidroksil (4.8 ppm). Spektrum resonan magnetik nukleus-karbon (13C-NMR)
    hidroksi-eter-POo
    telah menunjukkan kehadiran puncak karbon yang terikat dengan kumpulan hidroksil (75 ppm) dan
    karbon pada karbonil kumpulan eter (72 ppm). Kelikatan kinematik hidroksi-eter-POo
    adalah 234.4 cSt (40o
    C) dan 28.1
    cSt (100o
    C) dengan indeks kelikatan 156.
    Matched MeSH terms: Protons
  17. Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Asilar E, Bergauer T, et al.
    Eur Phys J C Part Fields, 2016;76(8):439.
    PMID: 28303081 DOI: 10.1140/epjc/s10052-016-4261-z
    A search for new physics is performed using events with two isolated same-sign leptons, two or more jets, and missing transverse momentum. The results are based on a sample of proton-proton collisions at a center-of-mass energy of 13[Formula: see text] recorded with the CMS detector at the LHC, corresponding to an integrated luminosity of 2.3 [Formula: see text]. Multiple search regions are defined by classifying events in terms of missing transverse momentum, the scalar sum of jet transverse momenta, the transverse mass associated with a [Formula: see text] boson candidate, the number of jets, the number of [Formula: see text] quark jets, and the transverse momenta of the leptons in the event. The analysis is sensitive to a wide variety of possible signals beyond the standard model. No excess above the standard model background expectation is observed. Constraints are set on various supersymmetric models, with gluinos and bottom squarks excluded for masses up to 1300 and 680[Formula: see text], respectively, at the 95 % confidence level. Upper limits on the cross sections for the production of two top quark-antiquark pairs (119[Formula: see text]) and two same-sign top quarks (1.7[Formula: see text]) are also obtained. Selection efficiencies and model independent limits are provided to allow further interpretations of the results.
    Matched MeSH terms: Protons
  18. Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Asilar E, Bergauer T, et al.
    Phys Rev Lett, 2017 Jan 13;118(2):021802.
    PMID: 28128610 DOI: 10.1103/PhysRevLett.118.021802
    A first search for pair production of dark matter candidates through vector boson fusion in proton-proton collisions at sqrt[s]=8  TeV is performed with the CMS detector. The vector boson fusion topology enhances missing transverse momentum, providing a way to probe supersymmetry, even in the case of a compressed mass spectrum. The data sample corresponds to an integrated luminosity of 18.5  fb^{-1}, recorded by the CMS experiment. The observed dijet mass spectrum is consistent with the standard model expectation. In an effective field theory, dark matter masses are explored as a function of contact interaction strength. The most stringent limit on bottom squark production with mass below 315 GeV is also reported, assuming a 5 GeV mass difference with respect to the lightest neutralino.
    Matched MeSH terms: Protons
  19. Oon YS, Ong SA, Ho LN, Wong YS, Oon YL, Lehl HK, et al.
    J Hazard Mater, 2017 Mar 05;325:170-177.
    PMID: 27931001 DOI: 10.1016/j.jhazmat.2016.11.074
    Monoazo and diazo dyes [New coccine (NC), Acid orange 7 (AO7), Reactive red 120 (RR120) and Reactive green 19 (RG19)] were employed as electron acceptors in the abiotic cathode of microbial fuel cell. The electrons and protons generated from microbial organic oxidation at the anode which were utilized for electrochemical azo dye reduction at the cathodic chamber was successfully demonstrated. When NC was employed as the electron acceptor, the chemical oxygen demand (COD) removal and dye decolourisation efficiencies obtained at the anodic and cathodic chamber were 73±3% and 95.1±1.1%, respectively. This study demonstrated that the decolourisation rates of monoazo dyes were ∼50% higher than diazo dyes. The maximum power density in relation to NC decolourisation was 20.64mW/m2, corresponding to current density of 120.24mA/m2. The decolourisation rate and power output of different azo dyes were in the order of NC>AO7>RR120>RG19. The findings revealed that the structure of dye influenced the decolourisation and power performance of MFC. Azo dye with electron-withdrawing group at para substituent to azo bond would draw electrons from azo bond; hence the azo dye became more electrophilic and more favourable for dye reduction.
    Matched MeSH terms: Protons
  20. Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Asilar E, Bergauer T, et al.
    Phys Rev Lett, 2017 Sep 15;119(11):111802.
    PMID: 28949210 DOI: 10.1103/PhysRevLett.119.111802
    A search is reported for a narrow vector resonance decaying to quark-antiquark pairs in proton-proton collisions at sqrt[s]=13  TeV, collected with the CMS detector at the LHC. The data sample corresponds to an integrated luminosity of 2.7   fb^{-1}. The vector resonance is produced at large transverse momenta, with its decay products merged into a single jet. The resulting signature is a peak over background in the distribution of the invariant mass of the jet. The results are interpreted in the framework of a leptophobic vector resonance and no evidence is found for such particles in the mass range of 100-300 GeV. Upper limits at 95% confidence level on the production cross section are presented in a region of mass-coupling phase space previously unexplored at the LHC. The region below 140 GeV has not been explored by any previous experiments.
    Matched MeSH terms: Protons
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