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Search for dark photons in decays of Higgs bosons produced in association with Z bosons in proton-proton collisions at √s=13 TeV
No full textA search is presented for a Higgs boson that is produced in association with a Z boson and that decays to an undetected particle together with an isolated photon. The search is performed by the CMS Collaboration at the Large Hadron Collider using a data set corresponding to an integrated luminosity of 137 fb(-1) recorded at a center-of-mass energy of 13 TeV. No significant excess of events above the expectation from the standard model background is found. The results are interpreted in the context of a theoretical model in which the undetected particle is a massless dark photon. An upper limit is set on the product of the cross section for associated Higgs and Z boson production and the branching fraction for such a Higgs boson decay, as a function of the Higgs boson mass. For a mass of 125 GeV, assuming the standard model production cross section, this corresponds to an observed (expected) upper limit on this branching fraction of 4.6 (3.6)% at 95% confidence level. These are the first limits on Higgs boson decays to final states that include an undetected massless dark photon
Performance of missing transverse momentum reconstruction in proton-proton collisions at √s=13 TeV using the CMS detector
No full textThe performance of missing transverse momentum ((p) over right arrow (miss)(T)) reconstruction algorithms for the CMS experiment is presented, using proton-proton collisions at a center-of-mass energy of 13 TeV, collected at the CERN LHC in 2016. The data sample corresponds to an integrated luminosity of 35.9 fb(-1). The results include measurements of the scale and resolution of (p) over right arrow (miss)(T), and detailed studies of events identified with anomalous (p) over right arrow (miss)(T). The performance is presented of a (p) over right arrow (miss)(T) reconstruction algorithm that mitigates the effects of multiple proton-proton interactions, using the "pileup per particle identification" method. The performance is shown of an algorithm used to estimate the compatibility of the reconstructed (p) over right arrow (miss)(T) with the hypothesis that it originates from resolution effects
Biyomalzeme uygulamaları için kitosan film ve ağların yüzey modifikasyonu
No full textThesis (Master)--Izmir Institute of Technology, Biotechnology and Bioengineering, Izmir, 2019Includes bibliographical references (leaves: 70-87)Text in English; Abstract: Turkish and EnglishModification of surface of biomaterials is a great interest for many years due to first contact of surface of materials with the biological fluids. This thesis aims to investigate surface modification effect on the chemical, surface wettability, protein adsorption as well biodegradability properties of dense chitosan (Ch) and asymmetric chitosan films (ACh). The surfaces of chitosan dense and asymmetric films were modified by ion implantation technique using carbon and carbon-nitrogen hybrid ions at a fluence of 1x1015 ions/cm2 and ion energy of 20kV. Chemical compositions of the film surfaces were analyzed by Fourier transform infrared spectroscopy (FTIR-ATR). Surface hydrophobicity measurements were conducted by static contact angle measurements. Protein adsorption on unmodified and modified surfaces on films was investigated as a function of time at various pH conditions. After ion implantation on chitosan films, both C and C-Nitrogen ion implantation, the surfaces become rougher and hydrophobic having moderate wettability (����� values in the range of 72-85°) and in good agreement with FTIR-ATR data findings. It was found pH dependence of the amount of protein adsorbed on the dense chitosan films as a function of time for both un-implanted and implanted films. BSA and fibrinogen were more adsorbed on the chitosan films at pH 5. The amount of BSA and fibrinogen protein adsorption was 0.97 and 1.33 gprotein/gfilm, respectively for 60 min incubation period. Protein adsorption enhanced for C and C+N2 ion implanted samples for BSA and fibrinogen, respectively due to the hydrophobic protein surface interaction effect. In vitro degradation results showed that ACh films degrade much faster (mass loss 57 %) than Ch films (40 %) due to the porous structure at the end of 3 weeks. However, the ion implanted Ch samples degraded much slower having mass loss of 30% and 17.7% for C+N2 and C implanted samples, respectively at the end of 3 weeks compared to un-implanted Ch films as 40 %. The results are in good agreement with water sorption and surface hydrophobicity of the implanted films. This study demonstrated that surface modification, as well as structure, changes the protein sorption, wettability and biodegradation properties of the chitosan films.Biyomalzemelerin yüzeylerinin değiştirilmesi, biyolojik ortam ile ilk teması malzeme yüzeyinin yapması nedeniyle büyük ilgi görmektedir. Bu tez, yoğun ve asimetrik kitosan filmlerin kimyasal, yüzey ıslanabilirliği, protein adsorpsiyonu ve biyolojik olarak parçalanabilirlik özellikleri üzerindeki yüzey modifikasyon etkisini araştırmayı amaçlamaktadır. Kitosan (Ch) yoğun ve asimetrik (ACh) filmlerin yüzeyleri, 20kV iyon enerjisi ve 1x1015ions/cm2 yonlukta karbon ve karbon-azot hibrit iyonları ile iyon implantasyon tekniği ile geliştirildi. Film yüzeylerinin kimyasal bileşimleri, Fourier dönüşümü kızılötesi spektroskopisi (FTIR-ATR) ile analiz edildi. Statik kontak açısı ölçümleri ile yüzey hidrofobikliği ölçümleri yapıldı. Modifiye edilmiş ve edilmemiş filmlerde protein adsorpsiyonu çeşitli pH koşullarında zamanın bir fonksiyonu olarak incelenmiştir. Kitosan filmlere, hem C hem de C-Azot iyon iyon implantasyonundan sonra, yüzeyler daha pürüzlü ve hidrofobik hale gelmiş olup, kontak açıları orta ıslanabilirliğe (72������85°) çıkmıştır. Bu veriler ile FTIR-ATR bulguları uyum içindedir. Yoğun kitosan filmlerine adsorbe edilen protein miktarının, hem implante edilmemiş hem de implante edilmiş filmler için zamanın bir fonksiyonu olarak pH etkisi çalışılmış, pH 5'te tutunmanın daha fazla olduğu görülmüştür. BSA ve Fibrinogen protein adsorpsiyon miktarı, 60 dakika inkübasyon sonrası 0,97 ve 1,33 gprotein/gfilm olarak bulunmuştur. Protein, hidrofobik yüzey etkile��iminden dolayı BSA ve Fibrinogen için C ve C+N2 iyonuyla implante edilmiş örnekler için protein adsorpsiyonu artmıştır. ��n vitro bozunma sonuçlarına göre, ACh filmler 3 hafta sonunda gözenekli yapıları nedeniyle yoğun kitosan filmlerden (%40) daha hızlı kütle kaybı gösterdi. Bununla birlikte, implante edilen C+N2 ve C ile implante edilen Ch filmler 3 hafta da %30 ve %17,7'lik kütle kaybı yaşamıştır. Implante edilmemiş Ch film numuneleri ise, çok daha yavaş bir şekilde, 3 hafta sonunda %40 bozulma görülmüştür. Bu sonuçlar, implante edilmiş filmlerin su emilimi ve yüzey hidrofobikliği sonuçları ile iyi bir uyum içindedir. Bu çalışma yüzey modifikasyonunun, yapının yanı sıra, kitosan filmlerinin protein emilimini, ıslanabilirliğini ve biyolojik bozunma özelliklerini etkilediğini göstermiştir.TUBITAK (108M391
Search for top quark partners with charge 5/3 in the same-sign dilepton and single-lepton final states in proton-proton collisions at √s=13 TeV
No full textA search for the pair production of heavy fermionic partners of the top quark with charge 5/3 (X 5/3 ) is performed in proton-proton collisions at a center-of-mass energy of 13 TeV with the CMS detector at the CERN LHC. The data sample analyzed corresponds to an integrated luminosity of 35.9 fb ?1 . The X 5/3 quark is assumed always to decay into a top quark and a W boson. Both the right-handed and left-handed X 5/3 couplings to the W boson are considered. Final states with either a pair of same-sign leptons or a single lepton are studied. No significant excess of events is observed above the expected standard model background. Lower limits at 95% confidence level on the X 5/3 quark mass are set at 1.33 and 1.30 TeV respectively for the case of right-handed and left-handed couplings to W bosons in a combination of the same-sign dilepton and single-lepton final states.[Figure not available: see fulltext.] © 2019, The Author(s)
Host genetics of cytomegalovirus pathogenesis
No full textPubMed: 31396258Human cytomegalovirus (HCMV) is a ubiquitous herpes virus (human herpes virus 5) with the highest morbidity and mortality rates compared to other herpes viruses. Risk groups include very young, elderly, transplant recipient, and immunocompromised individuals. HCMV may cause retinitis, encephalitis, hepatitis, esophagitis, colitis, pneumonia, neonatal infection sequelae, inflammatory, and age-related diseases. With an arsenal of genes in its large genome dedicated to host immune evasion, HCMV can block intrinsic cellular defenses and interfere with cellular immune responses. HCMV also encodes chemokines, chemokine receptors, and cytokines. Therefore, genes involved in human viral defense mechanisms and those encoding proteins targeted by the CMV proteins are candidates for host control of CMV infection and reactivation. Although still few in number, host genetic studies are producing valuable insights into biological processes involved in HCMV pathogenesis and HCMV-related diseases. For example, genetic variants in the immunoglobulin GM light chain can influence the antibody responsiveness to CMV glycoprotein B and modify risk of HCMV-related diseases. Moreover, CMV infection following organ transplantation has been associated with variants in genes encoding toll-like receptors (TLRs), programmed death-1 (PD-1), and interleukin-12p40 (IL-12B). A KIR haplotype (2DS4+) is proposed to be protective for CMV activation among hematopoietic stem cell transplant patients. Polymorphisms in the interferon lambda 3/4 (IFNL3/4) region are shown to influence susceptibility to CMV replication among solid organ transplant patients. Interestingly, the IFNL3/4 region is also associated with AIDS-related CMV retinitis susceptibility in HIV-infected patients. Likewise, interleukin-10 receptor 1 (IL-10R1) variants are shown to influence CMV retinitis development in patients with AIDS. Results from genome-wide association studies suggest a possible role for microtubule network and retinol metabolism in anti-CMV antibody response. Nevertheless, further genetic epidemiological studies with large cohorts, functional studies on the numerous HCMV genes, and immune response to chronic and latent states of infection that contribute to HCMV persistence are clearly necessary to elucidate the genetic mechanisms of CMV infection, reactivation, and pathogenesis
Search for a W ′ boson decaying to a τ lepton and a neutrino in proton-proton collisions at √s=13TeV
No full textA search for a new high-mass resonance decaying to a tau lepton and a neutrino is reported. The analysis uses proton-proton collision data collected by the CMS experiment at the LHC at root s= 13 TeV, corresponding to an integrated luminosity of 35.9 fb(-1). The search utilizes hadronically decaying tau leptons. No excess in the event yield is observed at high transverse masses of the tau and missing transverse momentum. An interpretation of results within the sequential standard model excludes W' boson masses below 4.0 TeV at 95% confidence level. Existing limits are also improved on models in which the W' boson decays preferentially to fermions of the third generation. Heavy W' bosons with masses less than 1.7-3.9 TeV, depending on the coupling in the non-universal G(221) model, are excluded at 95% confidence level. These are the most stringent limits on this model to date. (C) 2019 The Author(s). Published by Elsevier B.V
Search for pair-produced three-jet resonances in proton-proton collisions at √s=13 TeV
No full textA search has been performed for pair-produced resonances decaying into three jets. The proton-proton collision data used for this analysis were collected with the CMS detector in 2016 at a center-of-mass energy of 13 TeV and correspond to an integrated luminosity of 35.9 fb(-1). The mass range from 200 to 2000 GeV is explored in four separate mass regions. The observations show agreement with standard model expectations. The results are interpreted within the framework of R-parity violating SUSY, where pair-produced gluinos decay to a six quark final state. Gluino masses below 1500 GeV are excluded at 95% confidence level. An analysis based on data with multijet events reconstructed at the trigger level extends the reach to masses as low as 200 GeV. Improved analysis techniques have led to enhanced sensitivity, allowing the most stringent limits to date to be set on gluino pair production
Vertical van der Waals heterostructure of single layer InSe and SiGe
No full textWe present a first-principles investigation on the stability, electronic structure, and mechanical response of ultrathin heterostructures composed of single layers of InSe and SiGe. First, by performing total energy optimization and phonon calculations, we show that single layers of InSe and SiGe can form dynamically stable heterostructures in 12 different stacking types. Valence and conduction band edges of the heterobilayers form a type-I heterojunction having a tiny band gap ranging between 0.09 and 0.48 eV. Calculations on elastic-stiffness tensor reveal that two mechanically soft single layers form a heterostructure which is stiffer than the constituent layers because of relatively strong interlayer interaction. Moreover, phonon analysis shows that the bilayer heterostructure has highly Raman active modes at 205.3 and 43.7 cm(-1), stemming from the out-of-plane interlayer mode and layer breathing mode, respectively. Our results show that, as a stable type-I heterojunction, ultrathin heterobilayer of InSe/SiGe holds promise for nanoscale device applications
Towards uniform modeling and holistic testing of hardware and software
No full text1st International Informatics and Software Engineering Conference, IISEC 2019; 6 November 2019 through 7 November 2019This paper introduces an approach to uniform modeling and testing of hardware and software systems and their faults. As an example, for hardware under consideration, designs at a behavioral level will be used, implemented in Hardware Description Language (HDL). For software, an example will be borrowed from a graphical user interface design. Both examples will be modeled by finite state machines. The mutation of these models leads to lucid hardware and software fault models, respectively. Original models and their mutants will then be used to generate test cases for positive testing and negative testing, respectively, forming a holistic test strategy. A positive test is supposed to validate the system under legal (expected, regular) circumstances, whereas a negative test checks the behavior of the system under illegal (unexpected, irregular) situations. Non-trivial examples are used to validate and analyze the approach with respect to uniform modeling and testing capability. © 2019 IEEE
A digital interaction framework for managing knowledge intensive business processes
No full text7th Australasian Symposium on Service Research and Innovation, ASSRI 2018; 14 December 2018 through 14 December 2018Many business processes present in modern enterprises are loosely defined, highly interactive, involve frequent human interventions and coupled with a multitude of abstract entities defined within an enterprise architecture. Further, they demand agility and responsiveness to address the frequently changing business requirements. Traditional business process modelling and knowledge management technologies are not adequate to represent and support those processes. In this paper, we propose a framework for modelling such processes in a service-oriented fashion, extending an ontology-based enterprise architecture modelling platform. Finally, we discuss how our solution can be used as a stepping stone to cater for the management and execution of knowledge-intensive business processes in a broader context. © 2019, Springer Nature Switzerland AG