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Special functions with mod n symmetry and kaleidoscope of quantum coherent states
No full text32nd International Colloquium on Group Theoretical Methods in Physics (ICGTMP Group); JUL 09-13, 2018; Czech Tech Univ, Prague, Czech RepublicWOS:000537619600058The set of mod n functions associated with primitive roots of unity and discrete Fourier transform is introduced. These functions naturally appear in description of superposition of coherent states related with regular polygon, which we call kaleidoscope of quantum coherent states. Displacement operators for kaleidoscope states are obtained by mod n exponential functions with operator argument and non-commutative addition formulas. Normalization constants, average number of photons, Heinsenberg uncertainty relations and coordinate representation of wave functions with mod n symmetry are expressed in a compact form by these functions
Search for new physics in final states with a single photon and missing transverse momentum in proton-proton collisions at √s=13 TeV
No full textA search is conducted for new physics in final states containing a photon and missing transverse momentum in proton-proton collisions at s=13 TeV, using the data collected in 2016 by the CMS experiment at the LHC, corresponding to an integrated luminosity of 35.9 fb(-1). No deviations from the predictions of the standard model are observed. The results are interpreted in the context of dark matter production and models containing extra spatial dimensions, and limits on new physics parameters are calculated at 95% confidence level. For the two simplified dark matter production models considered, the observed (expected) lower limits on the mediator masses are both 950 (1150) GeV for 1 GeV dark matter mass. For an effective electroweak-dark matter contact interaction, the observed (expected) lower limit on the suppression parameter is 850 (950) GeV. Values of the effective Planck scale up to 2.85-2.90 TeV are excluded for between 3 and 6 extra spatial dimensions
Search for contact interactions and large extra dimensions in the dilepton mass spectra from proton-proton collisions at √s=13 TeV
No full textA search for nonresonant excesses in the invariant mass spectra of electron and muon pairs is presented. The analysis is based on data from proton-proton collisions at a center-of-mass energy of 13 TeV recorded by the CMS experiment in 2016, corresponding to a total integrated luminosity of 36 fb(-1). No significant deviation from the standard model is observed. Limits are set at 95% confidence level on energy scales for two general classes of nonresonant models. For a class of fermion contact interaction models, lower limits ranging from 20 to 32 TeV are set on the characteristic compositeness scale . For the Arkani-Hamed, Dimopoulos, and Dvali model of large extra dimensions, the first results in the dilepton final state at 13 TeV are reported, and values of the ultraviolet cutoff parameter (T) below 6.9 TeV are excluded. A combination with recent CMS diphoton results improves this exclusion to (T) below 7.7 TeV, providing the most sensitive limits to date in nonhadronic final states
Search for dark matter particles produced in association with a top quark pair at √s=13 TeV
No full textPubMed: 31012697A search is performed for dark matter particles produced in association with a top quark pair in proton-proton collisions at root s = 13 TeV. The data correspond to an integrated luminosity of 35.9 fb(-1) recorded by the CMS detector at the LHC. No significant excess over the standard model expectation is observed. The results are interpreted using simplified models of dark matter production via spin-0 mediators that couple to dark matter particles and to standard model quarks, providing constraints on the coupling strength between the mediator and the quarks. These are the most stringent collider limits to date for scalar mediators, and the most stringent for pseudoscalar mediators at low masses
Development of a simulation tool for vibration sensors based on Ф-OTDR interrogator
No full text2019 Innovations in Intelligent Systems and Applications Conference, ASYU 2019; Izmir; Turkey; 31 October 2019 through 2 November 2019This paper implements a recently reported modular approach to develop a simulation tool for the signals received in optical fiber vibration sensors interrogated by phase-sensitive optical time domain reflectometer. The phase fading effect on the demodulated phase information has been studied by using the developed model. © 2019 IEEE.Bu çalışmada, faza duyarlı zaman bölgesinde optik
yansıtıcı ünitesi tarafından sorgulanan fiber optik titreşim
sensörü simülasyon aracı geliştirilmesi amacıyla, literatürde yakın zamanda önerilen modüler bir yaklaşım uygulanmıştır. Geliştirilen model kullanılarak, demodüle edilen faz bilgisi üzerindeki faz sönümleme etkisi incelenmiştir
Prevalence, virulence characterization, and genetic relatedness of Listeria monocytogenes isolated from chicken retail points and poultry slaughterhouses in Turkey
No full textPubMed: 31478167Listeria monocytogenes is one of the most important foodborne pathogens and is a causal agent of listeriosis in humans and animals. The aim of this study was to determine the prevalence, serogroups, antibiotic susceptibility, virulence factor genes, and genetic relatedness of L. monocytogenes strains isolated from 500 poultry samples in Turkey. The isolation sources of 103 L. monocytogenes strains were retail markets (n = 100) and slaughterhouses (n = 3). L. monocytogenes strains were identified as serogroups 1/2a-3a (75.7%, lineage I), 1/2c-3c (14.56%, lineage I), 1/2b-3b-7 (5.82%, lineage II), 4a-4c (2.91%, lineage III), and 4b-4d-4e (0.97%, lineage III). Most of the L. monocytogenes strains (93.2%) were susceptible to the antibiotics tested. PCR analysis indicated that the majority of the strains (95% to 100%) contained most of the virulence genes (hylA, plcA, plcB, prfA, mpl, actA, dltA, fri, flaA inlA, inlC, and inlJ). Pulsed-field gel electrophoresis (PFGE) demonstrated that there were 18 pulsotypes grouped at a similarity of >90% among the strains. These results indicate that it is necessary to prevent the presence of L. monocytogenes in the poultry-processing environments to help prevent outbreaks of listeriosis and protect public health
Çökeltme yöntemi kullanılarak bor karbür tozlarının içindeki oksit katkılarının optimizasyonu
No full textThesis (Master)--Izmir Institute of Technology, Mechanical Engineering, Izmir, 2019Includes bibliographical references (leaves: 57-61)Text in English; Abstract: Turkish and EnglishThis study aims to precipitate oxides to boron carbide powders to achieve
homogeneous dispersion of additive which is essential for sintering. Fine boron carbide
powders were suspended in distilled water, then nitrate salts were solved in alcohol.
Solved nitrate salts were fed to mixture in high pH levels. Mixing stage of the
precipitation was done with both magnetic stirrer and ultrasonic treatment to investigate
the effect of the mixing method. After the precipitation, synthesized powders were
calcined under various atmospheres to eliminate the inorganic residues from the
precipitation process. The examination of the XRD graphs showed that the calcination
atmosphere is important for the oxide layer of the boron carbide powders. Inert
atmosphere restrained the formation of the boron oxide layer due to the lack of oxygen.
Methanol washing also eliminated the boron oxide layer. According to the zeta potential
analysis, surface characteristics were obtained better when the ultrasonic treatment was
applied during the precipitation. Ultrasonic treatment increased the dispersion of the
additives between the particles during the suspension stage of the precipitation.
Calcination time also affected the dispersion of the yttrium oxide at the sintered compacts
when the SEM images were observed. When the calcination time increased, dispersion
of the yttria was getting more agglomerated.Bu çalışmada, bor karbür tozları tane sınırları arasında sıvı faz sinterlemesi
sayesinde homojen dağılım elde etmek amacıyla oksit sinterleme katkıları kullanılarak
çökeltme yöntemi ile katkılanmıştır. Çökeltme yöntemi sırasında mikro ölçekli bor karbür
tozları sıvı içerisinde oksit katkıların nitrat tuzları ile askıda bırakılmıştır. Bu yöntemin
karıştırma aşaması hem manyetik karıştırıcı ile hem de ultrasonik karıştırıcı ile
gerçekleştirilmiştir. Çökeltmeden sonra elde edilen tozlar farklı atmosferlerde kalsine
edilecek inorganik kalıntıların giderilmesi amaçlanmıştır. XRD grafikleri gözlendiğinde
kalsinasyon atmosferinin bor karbür üzerindeki oksit tabakası için önemli olduğu
görülmüştür. Asal gazdan oluşan atmosferdeki oksijen azlığı sebebiyle boron oksit
tabakası gözlenmemiştir. Metanol ile yıkama işlemi de ayrıca oksit tabakasını
gidermektedir. Zeta potansiyel analizine göre, çökeltme sırasındaki ultrasonik karıştırma
işlemi daha iyi bir yüzey karakteristiği göstermiştir. Ultrasonik karıştırma askıda kalma
esnasında parçacıklar arasındaki dağılımın daha homojen olmasını sağlamıştır. Ayrıca
SEM görüntülerine bakıldığında kalsinasyon süresi sinterlenen peletlerdeki itriyum oksit
dağılımını da etkilemektedir. Kalsinasyon süresi arttıkça itriyum oksidin bor karbür
içerisinde öbeklendiği görülmüştür
Measurement of differential cross sections for inclusive isolated-photon and photon plus jet production in proton-proton collisions at √s=13TeV
No full textPubMed: 30872964Measurements of inclusive isolated-photon and photon+jet production in proton-proton collisions at =13TeV are presented. The analysis uses data collected by the CMS experiment in 2015, corresponding to an integrated luminosity of 2.26fb-1. The cross section for inclusive isolated photon production is measured as a function of the photon transverse energy in a fiducial region. The cross section for photon+jet production is measured as a function of the photon transverse energy in the same fiducial region with identical photon requirements and with the highest transverse momentum jet. All measurements are in agreement with predictions from next-to-leading-order perturbative QCD
Antibiotic-resistant staphylococcus aureus does not develop resistance to vanillic acid and 2-hydroxycinnamic acid after continuous exposure in vitro
No full textPubMed: 31572838Development of resistance to antibiotics is one of the major reasons of difficulties in treatments of diseases caused by antibiotic-resistant bacteria, and this resistance makes the investigation of alternative antimicrobials a key priority. Phenolic acids are plant- and fungi-originating natural antimicrobial products, and there is no known bacterial resistance after exposure to them. The purpose of this study was to investigate the resistance ability of bacteria against phenolic acids. Therefore, the ability of methicillin-resistant Staphylococcus aureus and methicillin-susceptible S. aureus to gain resistance against two phenolic acids and an antibiotic upon exposure to subinhibitory concentrations was tested. Herein, we evaluated the minimum inhibitory concentrations (MICs) of vanillic acid (VA), 2-hydroxycinnamic acid (2-HCA), and vancomycin in the beginning of the experiment and the MICs were found to be 2.5 mg/mL VA, 1.6 mg/mL 2-HCA, and 0.01 mg/mL vancomycin for both bacteria. Following continuous treatments with increasing subinhibitory concentrations, MICs were evaluated once more. Exposure to subinhibitory concentrations of vancomycin induced the development of resistance immediately; however, resistance to both phenolic acids could not be induced. These data indicated the potential of phenolic acids to be used as effective antimicrobials in the inhibition of antibiotic-resistant pathogenic bacteria
Search for a W′ boson decaying to a vector-like quark and a top or bottom quark in the all-jets final state
No full textA search for a heavy W resonance decaying to one B or T vector-like quark and a top or bottom quark, respectively, is presented. The search uses proton-proton collision data collected in 2016 with the CMS detector at the LHC, corresponding to an integrated luminosity of 35.9 fb(-1) at 13 TeV. Both decay channels result in a final state with a top quark, a Higgs boson, and a b quark, each produced with significant energy. The all-hadronic decays of both the Higgs boson and the top quark are considered. The final-state jets, some of which correspond to merged decay products of a boosted top quark and a Higgs boson, are selected using jet substructure techniques, which help to suppress standard model backgrounds. A W boson signal would appear as a narrow peak in the invariant mass distribution of these jets. No significant deviation in data with respect to the standard model background predictions is observed. Cross section upper limits on W boson production in the top quark, Higgs boson, and b quark decay mode are set as a function of the W mass, for several vector-like quark mass hypotheses. These are the first limits for W boson production in this decay channel, and cover a range of 0.01 to 0.43 pb in the W mass range between 1.5 and 4.0 TeV