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Search for an L μ − L τ gauge boson using Z → 4μ events in proton-proton collisions at √s=13 TeV
No full textA search for a narrow Z' gauge boson with a mass between 5 and 70 GeV resulting from an L-mu - L-tau U (1) local gauge symmetry is reported. Theories that predict such a particle have been proposed as an explanation of various experimental discrepancies, including the lack of a dark matter signal in direct-detection experiments, tension in the measurement of the anomalous magnetic moment of the muon, and reports of possible lepton flavor universality violation in B meson decays. A data sample of proton-proton collisions at a center-of-mass energy of 13 TeV is used, corresponding to an integrated luminosity of 77.3 fb(-1) recorded in 2016 and 2017 by the CMS detector at the LHC. Events containing four muons with an invariant mass near the standard model Z boson mass are analyzed, and the selection is further optimized to be sensitive to the events that may contain Z -> Z'mu mu -> 4 mu decays. The event yields are consistent with the standard model predictions. Upper limits of 10(-8)-10(-7) at 95% confidence level are set on the product of branching fractions B(Z -> Z'mu mu)B(Z' -> mu mu), depending on the Z' mass, which excludes a Z' boson coupling strength to muons above 0.004-0.3. These are the first dedicated limits on L-mu - L-tau models at the LHC and result in a significant increase in the excluded model parameter space. The results of this search may also be used to constrain the coupling strength of any light Z' gauge boson to muons. (C) 2019 The Author(s). Published by Elsevier B.V
Search for a standard model-like Higgs boson in the mass range between 70 and 110 GeV in the diphoton final state in proton-proton collisions at √s=8 and 13 TeV
No full textThe results of a search for a standard model-like Higgs boson in the mass range between 70 and 110 GeV decaying into two photons are presented. The analysis uses the data set collected with the CMS experiment in proton-proton collisions during the 2012 and 2016 LHC running periods. The data sample corresponds to an integrated luminosity of 19.7 (35.9) fb(-1) at root s = 8 (13) TeV. The expected and observed 95% confidence level upper limits on the product of the cross section and branching fraction into two photons are presented. The observed upper limit for the 2012 (2016) data set ranges from 129 (161) fb to 31 (26) fb. The statistical combination of the results from the analyses of the two data sets in the common mass range between 80 and 110 GeV yields an upper limit on the product of the cross section and branching fraction, normalized to that for a standard model-like Higgs boson, ranging from 0.7 to 0.2, with two notable exceptions: one in the region around the Z boson peak, where the limit rises to 1.1, which may be due to the presence of Drell-Yan dielectron production where electrons could be misidentified as isolated photons, and a second due to an observed excess with respect to the standard model prediction, which is maximal for a mass hypothesis of 95.3 GeV with a local (global) significance of 2.8 (1.3) standard deviations. (C) 2019 The Author(s). Published by Elsevier B.V
Doğa esinli tasarımı anlamak ve tasarım müfredatına etkisini yorumlamak üzerine bir model
No full textThesis (Master)--Izmir Institute of Technology, Architecture, Izmir, 2019Includes bibliographical references (leaves: 98-106)Text in English; Abstract: Turkish and EnglishInspirations from nature is widely used in the field of design. Rising concerns about the irreversible and hazardous effects of humankind, direct the developments in the field of design and technology once again to nature. Biomimicry is a term that connotes the life and imitation of nature and this imitation can be applied also in the context of design as in many areas of life. Nowadays, design has started to use not only the simulation of the shapes of nature but also the structural and systemic features of the nature. In the field of architecture, there is a rising interest towards buildings designed by bio-inspired processes together with the seek for sustainable solutions. Architecture schools which are following the advancements in contemporary built environment and building technologies started to include bio-inspired design courses into their curriculums. Within the scope of this thesis the prominent bio-inspired architectural products are examined in order to; (1) a categorization proposal is developed to read bioinspired design approaches, (2) the impact and the place of bio-inspired design approaches in leading architectural school’s curriculum.Tasarım alanında doğadan esinlenmeler oldukça yaygın olarak kullanılmaktadır.
İnsanoğlunun doğa üzerindeki geri döndürülemez etkileri ve bunların yarattığı endişeler
tasarım ve teknoloji alanındaki gelişmelerin yönü doğayı korumaya yönelik üretimlere
çevrildi. Biyomimikri köklerine bakıldığında yaşam ve takliti bir arada bünyesinde
barındırmaktadır ve bu taklit hayatın pek çok alanında olduğu gibi tasarım bağlamında
da uygulanabilmektedir. Günümüzde tasarım, daha önceki doğayı taklit eden
yaklaşımların ötesinde doğanın sadece şekillerinin simülasyonunu içermekle kalmayıp
aynı zamanda yapısal ve sistemsel özelliklerini de tasarım ilkesi olarak kullanmaya
başlamıştır. Mimarlık camiasında doğadan esinlenerek tasarlanmış binalar ve bunlara
duyulan ilgi sürdürülebilirlik arayışlarıyla da giderek artmaktadır. Yapılı çevre ve yeni
teknolojilerle entegre olan mimarlık okulları müfredatlarına doğayı taklit eden tasarım
derslerini dahil etmeye başlamışlardır. Bu tezin amacı kapsamında doğadan esinlenen
mimarlık ürünlerinin başlıca örnekleri incelenerek; (1) doğa esinli tasarım
yaklaşımlarını okumak için bir sınıflandırma önerisi geliştirilmiştir, (2) doğa esinlin
tasarım yaklaşımlarının önde gelen mimarlık okullarının müfredatına ve önde gelen
mimarlık okullarının müfredatındaki yeri incelenmiştir
Search for resonant tt¯ production in proton-proton collisions at s√=13 TeV
No full textA search for a heavy resonance decaying into a top quark and antiquark (tt) pair is performed using proton-proton collisions at p s = 13TeV. The search uses the data set collected with the CMS detector in 2016, which corresponds to an integrated luminosity of 35.9 fb. The analysis considers three exclusive fi nal states and uses reconstruction techniques that are optimized for top quarks with high Lorentz boosts, which requires the use of nonisolated leptons and jet substructure techniques. No signi fi cant excess of events relative to the expected yield from standard model processes is observed. Upper limits on the production cross section of heavy resonances decaying to a tt pair are calculated. Limits are derived for a leptophobic topcolor Z 0 resonance with widths of 1, 10, and 30%, relative to the mass of the resonance, and exclude masses up to 3.80, 5.25, and 6.65TeV, respectively. Kaluza-Klein excitations of the gluon in the Randall-Sundrum model are excluded up to 4.55TeV. To date, these are the most stringent limits on tt resonances
Measurement and interpretation of differential cross sections for Higgs boson production at √s=13 TeV
No full textDifferential Higgs boson (H) production cross sections are sensitive probes for physics beyond the standard model. New physics may contribute in the gluon-gluon fusion loop, the dominant Higgs boson production mechanism at the LHC, and manifest itself through deviations from the distributions predicted by the standard model. Combined spectra for the H -> gamma gamma, H -> ZZ, and H -> b (b) over bar decay channels and the inclusive Higgs boson production cross section are presented, based on proton-proton collision data recorded with the CMS detector at root s = 13 TeV corresponding to an integrated luminosity of 35.9 fb(-1). The transverse momentum spectrum is used to place limits on the Higgs boson couplings to the top, bottom, and charm quarks, as well as its direct coupling to the gluon field. No significant deviations from the standard model are observed in any differential distribution. The measured total cross section is 61.1 +/- 6.0 (stat) +/- 3.7 (syst) pb, and the precision of the measurement of the differential cross section of the Higgs boson transverse momentum is improved by about 15% with respect to the H -> gamma gamma channel alone. (C) 2019 The Author(s). Published by Elsevier B.V
Peroksidasyon aktivitesini artırmak için sitokrom P450 enziminin yönlendirilmiş evrimi
No full textThesis (Master)--Izmir Institute of Technology, Bioengineering, Izmir, 2019Includes bibliographical references (leaves: 57-61)Text in English; Abstract: Turkish and EnglishDirected evolution, mimicking the natural selection, is a powerful tool to create novel enzymes. Evolution of natural enzymes to achieve desired properties are performed in iterative rounds of random mutagenesis followed by a screening/selection method. Enzyme activity can be enhanced with substituting the active site amino acids in the enzyme. CYP119, a member of cytochrome P450 protein family, is a thermophilic enzyme extracted from Sulfolobus acidocaldarius that exhibits monooxygenase, peroxidase and oxidoreductase activity. These properties give CYP119 a potential to be used in production of fine chemicals and pharmaceuticals. Herein, two different mutant libraries of CYP119, containing substituted amino acids at Thr213-Thr214 and Val151- Phe153 positions, constructed via combinatorial active site saturation test (CAST), and screened for improved peroxidation activity. Additionally, fluorescence based Amplex Red peroxidation activity assay using hydrogen peroxide as cofactor of CYP119 was optimized. Screening of mutant libraries resulted four improved CYP119 mutant enzymes from Thr213-Thr214 mutant library. Val151-Phe153 mutant library did not yield any improved peroxidation activity mutants which indicated amino acid substitutions at 151- 153 positions do not have any effect on peroxidation activity of CYP119. Furthermore, effect of substituted amino acids at predetermined positions were analyzed. Substrate, Amplex Red, makes single or double hydrogen bond when molecular docking was performed on improved mutant enzymes also distance of nitrogen atom in Amplex Red to heme iron is closer than wild type CYP119 in improved mutant enzymes. Thus, increasing the peroxidation activity of mutant CYP119 enzymes.Yönlendirilmiş evrim, doğal seçilimden esinlenilmiş ve yeni enzimler tasarlamak
için kullanılan etkili bir yöntemdir. Doğada bulunan enzimlere, istenilen özellikleri
eklemek ya da geliştirmek için, ötelemeli rastgele mutasyon ve devamında tarama/seçme
metodu uygulanır. Enzim aktiviteleri, enzimin aktif kısmında bulunan amino asitlerin
değiştirilmesi ile yükseltilebilir. Sitokrom P450 protein ailesinin üyesi olan CYP119,
Sulfolobus acidocaldarius’tan izole edilmiştir ve termofilik bir enzimdir. Buna ek olarak
CYP119 enzimi monooksijenaz, peroksidaz ve oksidoredüktaz aktivitesi göstermektedir.
Bu özellikleri ile CYP119 enzimi saf kimyasalların ve farmasötiklerin üretiminde
kullanılmak üzere potansiyel taşımaktadır. Bu çalışmada, Thr213.-Thr214 ve Val151-
Phe153 pozisyonlarında değişiklik yapılmış iki farklı CYP119 mutant kütüphanesi
artırılmış peroksidaz aktivitesi için taranmıştır. Buna ek olarak, hidrojen peroksiti
CYP119’un kofaktörü olarak kullanan, floresan tabanlı Amplex Red testi optimize
edilmiştir. Mutant kütüphanelerinin taranması, Thr213-Thr214 mutant kütüphanesinden
dört adet peroksidasyon aktivitesi geliştirilmiş mutanın açığa çıkarılmasını sağlamıştır.
Val151-Phe153 kütüphanesinden peroksidasyon aktivitesi geliştirilmiş mutant
bulunamamıştır ve 151-153 pozisyonlarındanki amino asit değişikliklerinin aktiviteye
herhangi bir etkisi olmadığı gözlemlenmiştir. Ek olarak, önceden belirlenmiş
pozisyonlardaki amino asitlerin değiştirilmesinin etkileri de incelenmiştir. Moleküler
doking uygulandığında, Amplex Red substratı, özellikle geliştirilmiş mutant enzimler ile
tekli veya ikili hidrojen bağı yapmaktadır. Bununla birlikte, geliştirilmiş mutant
enzimlerde, Amplex Red’de bulunan azot atomunun heme grubunda bulunan demir
atomuna, yabanıl tipe göre, daha yakın olduğu gözlemlenmiştir. Böylece, seçilen mutant
CYP119 enzimler geliştirilmiş peroksidasyon aktivitesine sahip olmuştur.TÜBİTAK (116Z380
Computation time efficient stiffness analysis of the modified R-CUBE mechanism
No full textParallel manipulators are known to be more stiff than the serial manipulators. However, modeling the stiffness for parallel manipulators are difficult compared to serial manipulators due to the constrained structure and passive joints. In addition, computation of the stiffness model for parallel manipulators are exhausting since it requires an iterative solution algorithm due requirement of force-position convergence of all serial chains connecting to the same mobile platform. Direct solutions are faster however, they lack in accuracy. In this study, direct solution is preferred for real-time application and analytic stiffness model of the modified R-CUBE mechanism is obtained by using Virtual Joint Method (VJM). The finite element (FE) model is constructed and simulated to validate the analytical model. Then, a combination of external wrenches N in various directions are applied on the mobile platform in both FE and VJM in some critical poses. Finally, the computed numerical results are listed and compared along with their computation times. © Springer Nature Switzerland AG 201
Joint routing and resource allocation for software defined mobile networks
No full text30th IEEE Annual International Symposium on Personal, Indoor and Mobile Radio Communications, PIMRC 2019; 8 September 2019 through 11 September 2019The need for software defined mobile networking (SDMN) increases to manage the complexity in communication networks for the fifth generation mobile networks and beyond, with increasing diverse demand on data traffic in wireless environments. The separation of the data and control planes offers flexibility in future networks with SDMN by taking into account to the wireless access problem in complex radio environments. In this paper, we propose an efficient joint routing and resource allocation algorithm to minimize the cost based on power consumption while satisfying both throughput and delay requirement of the flows under a given capacity of links in night time traffic through SDMN. The power consumption is determined based on the number of active OpenFlow switches and active ports in the network. In the proposed joint algorithm, we put the selected network components to sleep mode in order to reduce overall network power consumption. The performances of the proposed algorithm are illustrated under different throughput constraints in various network topologies and scenarios in night-time traffic. © 2019 IEEE
From requirements to data analytics process: An ontology-based approach
No full text16th International Conference on Business Process Management, BPM International Workshops 2018; 9 September 2018 through 14 September 2018 -Comprehensively describing data analytics requirements is becoming an integral part of developing enterprise information systems. It is a challenging task for analysts to completely elicit all requirements shared by the organization’s decision makers. With a multitude of data available from e-commerce sites, social media and data warehouses selecting the correct set of data and suitable techniques for an analysis itself is difficult and time-consuming. The reason is that analysts have to comprehend multiple dimensions such as existing analytics techniques, background knowledge in the domain of interest and the quality of available data. In this paper, we propose to use semantic models to represent different spheres of knowledge related to data analytics space and use them to assist in analytics requirements definition. By following this approach users can create a sound analytics requirements specification, linked with concepts from the operation domain, available data, analytics techniques and their implementations. Such requirements specifications can be used to drive the creation and management of analytics solutions, well aligned with organizational objectives. We demonstrate the capabilities of the proposed method by applying on a data analytics project for house price prediction. © 2019, Springer Nature Switzerland AG
Genetic determinants of musculoskeletal adaptations to unloading and reloading
No full text9th International Conference on Recent Advances in Space Technologies (RAST); JUN 11-14, 2019; Istanbul, TurkeyLack of weight bearing is one of the most critical limitations for long term health of bone tissue in space missions. In this study, we performed a series of Quantitative Trait Locus (QTL) analysis of musculoskeletal traits to define genomic modulators adaptations to mechanical unloading and subsequent reloading using a genetically heterogeneous (F2 BALBxC3H) female mouse population. The identified regions on genome contain genes that regulate musculoskeletal adaptations to weightlessness and further studies may help to categorize individuals that are at risk for greater tissue loss during weightlessness and/or low tissue recovery during reambulation