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Xenograft Tumor Volume Measurement in Nude Mice: Estimation of 3D Ultrasound Volume Measurements Based on Manual Caliper Measurements
No full textObjectives: Volume measurement of subcutaneous xenograft tumors in nude mice models is an important metric to assess tumor growth or response to therapy. Manual calipers are widely used for this purpose. But the measurements with manual calipers may be inaccurate. Contrarily, three-dimensional (3D) ultrasonographic measurements give reliable and accurate tumor volume calculation. We aim to; evaluate the accuracy of common four formulas given in the literature to estimate xenograft tumor volumes based on manual caliper measurements and offer a new coefficient for a better estimation of the tumor volumes. Patients and Methods: Detailed manual diameter measurements of xenograft tumors were in 14 nude mice performed using Vernier caliper. Tumor volumes were calculated using the suggested formulas in the literature based on manual measurements. 3D ultrasound volume measurements were performed on same xenograft tumors using high resolution Vevo 2100 imaging system. To propose a new coefficient; means of ratio between manual and ultrasound volume measurement values were used. Also, data set was divided into two subgroups as tumor volume under 800 mm3 and over 800 mm3. New coefficients for each subgroup were defined. Results: Only with prolate ellipsoid formula there was no statistically significant difference between volume measurements with two methods (p=0,24). Our proposed formula (0,45 L*W*H) could estimate tumor volumes as good as prolate ellipsoid formula. Coefficient 0,35 and 0,81 in the same formula were found efficient in the selected subgroups. Conclusion: Using one common coefficient/formula for tumor volume estimation in any tumor size can be inaccurate. Appropriate coefficient should be chosen according to the dataset worked with
Effects of Framing Errors on the Performance of Molecular Communications With Memory
No full textGalmes, Sebastia/0000-0003-0505-9741; Atakan, Baris/0000-0002-2310-8175In conventional digital communication systems, synchronous transmission is achieved by embedding the clocking information into the data signal. However, the implementation of this technique in molecular communication systems, which rely on the diffusion of molecules as information carriers, becomes very complex due to the randomness of the diffusion process. Hence, in this paper we consider the molecular communication between two nanoscale devices with no exchange of any clock signal. To initiate the communication, the transmitter sends a special molecular symbol called beacon in order to trigger the detection process in the receiver. Therefore, this beacon symbol is equivalent to the start bit used for framing in asynchronous serial communication systems. We assume that both transmitter and receiver clocks are perfect, but not synchronized. Accordingly, the analysis focuses on the effects of framing errors on the performance of the molecular channel, measured via the symbol error probability. These errors are inherent to the random nature of the beacon arrival instant, which tends to degrade the alignment between the transmitter and receiver frames. We also assume a molecular channel with any level of inter-symbol interference and the use of different types of molecules to encode information symbols. We validate the derived SEP expression by means of extensive simulation experiments, and finally we develop a design scheme for the beacon symbol that satisfactorily mitigates the effects of framing errors.Scientific and Technological Research Council of Turkey (TUBITAK)Turkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [119E041]This work was supported by the Scientific and Technological Research Council of Turkey (TUBITAK) under Grant 119E041
MeV ölçeğinde ayarlı ve geometrik vektör alanlar
No full textThesis (Doctoral)--Izmir Institute of Technology, Physics, Izmir, 2020Includes bibliographical references (leaves: 38-47)Text in English; Abstract: Turkish and EnglishIn this thesis, we have studied gauged and geometric vector fields at the MeV scale in two main parts. The basic framework of these two parts are given briefly as follows. In the first part (Chapter \ref{chapter-U(1)}), we have built a family-nonuniversal model populated by an MeV-scale sector with a minimal new field content which explains the recent anomalous beryllium decays. Excited beryllium has been observed to decay into electron-positron pairs with a anomaly. The process is properly explained by a MeV proto-phobic vector boson. In this thesis, we consider a family-nonuniversal that is populated by the gauge boson and a scalar field . The kinetic mixing of with the hypercharge gauge boson, as we show by a detailed analysis, generates the observed beryllium anomaly. We show that beryllium anomaly can be explained by an MeV-scale sector with a minimal new field content. In the second part (Chapter \ref{chapter-GDM}), we have shown how a light vector particle can arise from metric-affine gravity and how this particle fits the current data and constraints on the dark matter. We show that, metric-affine gravity , which involves metric tensor and affine connection as two independent fields, dynamically reduces, in its minimal form, to the usual gravity plus a massive vector field. The vector is neutral and long-living when its mass range lies in the range . Its scattering cross section from nucleons, which is some 60 orders of magnitude below the current bounds, is too small to facilitate direct detection of the dark matter. This property provides an explanation for whys and hows of dark matter searches. We show that due to its geometrical origin the couples only to fermions. This very feature of the makes it fundamentally different than all the other vector dark matter candidates in the literature. The geometrical dark matter we present is minimal and self-consistent not only theoretically but also astrophysically in that its feebly interacting nature is all that is needed for its longevity.Bu tezde MeV ölçeğinde ayarlı ve geometrik vektör alanları iki ana bölümde çalıştık. Bu iki bölümün ana hatları kısaca aşağıdaki gibidir. İlk kısımda (Bölüm 2) , yakın zamandaki olağan dışı berilyum bozunumlarını her yönüyle açıklayan, minimum yeni alan içeren MeV ölçeğindeki bir sektör ile desteklemiş bir model oluşturduk. Uyarılmış berilyumun elektron-positron çiftine olağan dışı bozunumu düzeyinde gözlemlendi. Bu proses 17-MeV'lik proto-phobic bir vektör bozonla açıklanmıştır. Bu tezde, bir ayar bozonu ve altında yüklü Standard Model (SM) ayar simetrisi altında singlet olan bir skaler alanından oluşan, fermion ailelerinde evrensel olmayan bir ele alıyoruz. SM kiral fermiyon ve skaler alaları altında yüklüdür ve biz bu yüklerin anomaliden ari olmalarını sağlıyoruz. Cabibbo-Kobayashi-Maskawa (CKM) matrisi, tarafından sağlanan yüksek boyutlu Yukawa etkileşimleri ile doğru bir şekilde üretilmektedir. 'ın birinci fermiyon jenerasyonuna olan vektör ve aksiyal-vektör akım kuplajları çeşitli deneylerden gelen tüm kısıtlamaları sağlamaktadır. bozonu hiperyük ayar bozonu ile kinetik karışım yapabilir ve SM benzeri Higgs alanına doğrudan kuplaj yapabilir. Detaylı bir analiz ile gösterceğimiz üzere, 'ın hiperyük ayar bozonu ile kinetik karışımı gözlemlenmiş olan berilyum anomalisini meydana getirir. Bulduğumuz o ki, berilyum anomalisi minimal yeni alan içeren MeV ölçeğindeki bir sektör ile her yönüyle açıklanabilir. Oluşturduğumuz bu minimal model çeşitli olağan dışı SM bozunumlarının tartışılabileceği bir yapıdadır. İkinci kısımda (Bölüm 3), hafif bir vektör parçacığın metrik-afin kütleçekiminden nasıl elde edilebileceğini ve eldeki karanlık madde verilerine ve kısıtlamalarına nasıl fit ettiğini gösterdik. Düz rotasyon eğrilerinden yapı oluşumuna kadar çeşitli olaylar için gerekli olan karanlık madde sadece nötral ve uzun ömürlü değil aynı zamanda bilinen maddeden oldukça izole gibi görünüyor. Burada gösteriyoruz ki metrik tensörü ve afin bağlantısını iki bağımsız alan olarak içeren minimal formdaki metrik-afin kütleçekimi dinamik olarak bilinen kütleçekim artı kütleli bir vektör alana indirgenir. Yalnızca quark, lepton ve kütleçekimle etkileşen vektörü kütle aralığı aralığında iken nötral ve uzun ömürlüdür (evrenin yaşından daha uzun). Karanlık maddenin günümüz kıstlamalarından mertebe daha aşağıda olan nükleonlardan saçılma tesir kesiti doğrudan keşfedilmeye olanak sağlaması için çok fazla küçüktür. Bu özellik karanlık madde araştırmalarının nedenleri ve nasıllarına bir açıklama sağlamaktadır. Gösteriyoruz ki geometrik doğasından dolayı skaler ve bozonlara kuplaj yapmamaktadır. yalnızca fermiyonlara kuplaj yapmaktadır. 'nün bu belirgin özelliği kendisini litertürdeki diğer tüm vektör karanlık madde adaylarından farklı kılar. Sunduğumuz geometrik karanlık madde sadece teorik açıdan minimal ve kendi içinde uyumlu değil aynı zamanda astrofiziksel olarak da öyledir, öyle ki zayıf etkileşen doğası uzun ömürlü olması için gerekli olan tek şeydir
Enerji uygulamaları için çoklu metal oksit foto-elektrotların geliştirilmesi
No full textThesis (Master)--Izmir Institute of Technology, Chemistry, Izmir, 2020Includes bibliographical references (leaves: 75-82)Text in English; Abstract: Turkish and EnglishWater splitting via artificial photosynthesis uses only sunlight and water to produce hydrogen and oxygen. Hydrogen can be used as a green energy source. To be able this reaction to occur there is a catalyst needed as reaction center. Platinum and Iridium are the state-of-art catalyst used for water splitting reactions. The goal of this study is to develop an earth abundant, highly stable and efficient catalyst as an alternative to noble metal catalysts. For this purpose, ABO3 type perovskites was chosen to study for their abundancy and proven electrochemical efficiencies. BSCF was chosen as the starting point of this study because it is known for its great catalytic activity compared to state-of-art catalysts such as Iridium Oxide. To enhance the stability and catalytic activity of synthesized perovskite oxides, several foreign atoms (dopants) were introduced to their structure from B-site. Each perovskite was synthesized by the EDTA-Citrate complexing Sol-Gel method. Also, for dopants, cost-efficient and electron conductive elements was chosen in each study. As HER catalysts, manganese, zinc, and copper were introduced to BSCF structure as dopant, while for OER, silver was used as a dopant. In this study, catalytic activities and stabilities were tested by electrochemical methods. All electrochemical measurements were performed in alkaline media by three-electrode configurations. Perovskite oxides were prepared by the coating of their inks on Ni foam substrates by drop coating for HER and OER activity measurements by electrochemical methods. For the bulk and surface characterization of synthesized perovskite oxide powders, SEM, XRD, XPS, and BET analysis was performed.Yapay fotosentez ile suyun ayrıştırılması yöntemi, su ve güneş ışığı enerjisini kullanarak yenilenebilir enerji kaynağı olan hidrojen elde edilmesini sağlar. Suyun elektrolitik ayrıştırılması yöntemi mekanizma olarak yavaş ve verimi düşük olduğundan markette halihazırda kullanılmakta olan fosil yakıtlarla yarışmakta yetersiz kalır. Bu sebepten dolayı, katalizörler kullanılmaktadır. Bu çalışmanın amacı katalizör olarak kullanılan iridyum ve platin gibi soy metaller yerine yer yüzünde bulunma yüzdesi fazla olan ve düşük maliyetli katalizörler sentezlemektir. ABO3 tipi perovskit yapıları bu kritere uymakla birlikte elektrokimyasal aktiviteleri açısından da daha önceki çalışmalarda kendilerini kanıtlamışlardır. Özellikle Ba0.5Sr0.5Co0.8Fe0.2O3-δ (BSCF), su ayrışması katalizörleri arasında en verimlisi olarak kabul edilen iridyum oksitten daha yüksek verim sağladığından dolayı bu çalışmanın ana konusu olarak tercih edilmiştir. BSCF'nin kararlılık ve katalitik aktivitesini arttırmak için, kristalin B atom grubuna yabancı atomlar eklenmiştir. Hidrojen çıkış reaksiyonlarına yönelik aktivitenin arttırılması için yapıya mangan, çinko ve bakır eklenirken, oksijen çıkış reaksiyonlarına yönelik aktivite çalışmalarında gümüş atomları eklenmiştir. Çalışmada kullanılan bütün perovskitler Sol-Jel metoduna göre sentezlenip, kompleksleştirici olarak EDTA – Sitrat kullanılmıştır. Elektrokimyasal karakterizasyonlar için, sentezlenen toz yapıları mürekkep haline getirildikten sonra nikel köpüğün üzerine damlatılarak kaplanmıştır. Elektrokimyasal ölçümler alkali ortamda alınırken üçlü elektrot konfigürasyonu kullanılmıştır. Yapısal ve yüzeysel karakterizasyonlar için XRD, XPS BET ve SEM analizleri kullanılmıştır
Chitosan-hybrid poss nanocomposites for bone regeneration: The effect of poss nanocage on surface, morphology, structure and in vitro bioactivity
No full textPubMed: 31622724POSS, regarded as the smallest silica particle, is widely used as nanofiller in polymer systems. POSS-based nanocomposites are deduced as novel materials having potency for biomedical applications owing to the enhanced biocompatibility and physicochemical characteristics. The aim of this work was to integrate the beneficial features of chitosan (CS) and OctaTMA-POSS nanoparticle to design nanocomposite for bone tissue regeneration. The nanocomposite scaffolds were fabricated by freeze-drying. The effects of POSS incorporation on morphology and structure of CS matrix were examined. Bioactivity and osteogenic effects of the POSS nanoparticles were investigated with cytocompatibility, cell proliferation, alkaline phosphatase activity, osteocalcin production and biomineralization assays. PUSS incorporation altered the surface morphology by increasing surface roughness. Nanocomposite scaffolds with 82-90% porosity exhibited an increase in compression modulus of scaffolds (78-107 kPa) compared to control CS group (56 kPa). Results indicated that CS-POSS scaffolds were found cytocompatible with 3T3, MG-63 and Saos-2 cell lines. POSS incorporation showed promising effects on osteoblast adhesion and proliferation as well as increasing ALP activity, octeocalcin secretion and biomineralization of cells. (C) 2019 Elsevier B.V. All rights reserved
Searches for physics beyond the standard model with the MT2 variable in hadronic final states with and without disappearing tracks in proton-proton collisions at √s=13Te
No full textPubMed: 31976987Two 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 13Te, collected by the CMS experiment at the LHC in 2016-2018 and corresponding to an integrated luminosity of 137fb-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 MT2 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
Search for a heavy pseudoscalar Higgs boson decaying into a 125 GeV Higgs boson and a Z boson in final states with two tau and two light leptons at √s=13 TeV
No full textA search is performed for a pseudoscalar Higgs boson, A, decaying into a 125 GeV Higgs boson h and a Z boson. The h boson is specifically targeted in its decay into a pair of tau leptons, while the Z boson decays into a pair of electrons or muons. A data sample of proton-proton collisions collected by the CMS experiment at the LHC at root s = 13 TeV is used, corresponding to an integrated luminosity of 35.9 fb(-1). No excess above the standard model background expectations is observed in data. A model-independent upper limit is set on the product of the gluon fusion production cross section for the A boson and the branching fraction to Zh -> ll tau tau. The observed upper limit at 95% confidence level ranges from 27 to 5 fb for A boson masses from 220 to 400 GeV, respectively. The results are used to constrain the extended Higgs sector parameters for two benchmark scenarios of the minimal supersymmetric standard model
Observation of the Λb 0→J/ψΛϕ decay in proton-proton collisions at √s=13TeV
No full textThe observation of the Lambda(0)(b) -> J/psi Lambda phi decay is reported using proton-proton collision data collected at root s = 13TeV by the CMS experiment at the LHC in 2018, corresponding to an integrated luminosity of 60fb(-1). The ratio of the branching fractions B(Lambda(0)(b) -> J/psi Lambda phi)/B(Lambda(0)(b) > psi(2S)Lambda) is measured to be (8.26 +/- 0.90 (stat) +/- 0.68 (syst) +/- 0.11 (B)) x 10(-2), where the first uncertainty is statistical, the second is systematic, and the last uncertainty reflects the uncertainties in the world-average branching fractions of phi and psi(2S) decays to the reconstructed final states. (C) 2020 The Author. Published by Elsevier B.V
Mixed higher-order anisotropic flow and nonlinear response coefficients of charged particles in PbPb collisions at √s(NN)=2.76 and 5.02 TeV
No full textPubMed:32589167Anisotropies in the initial energy density distribution of the quark-gluon plasma created in high energy heavy ion collisions lead to anisotropies in the azimuthal distributions of the final-state particles known as collective anisotropic flow. Fourier harmonic decomposition is used to quantify these anisotropies. The higher-order harmonics can be induced by the same order anisotropies (linear response) or by the combined influence of several lower order anisotropies (nonlinear response) in the initial state. The mixed highe-rorder anisotropic flow and nonlinear response coefficients of charged particles are measured as functions of transverse momentum and centrality in PbPb collisions at nucleon-nucleon center-of-mass energies root s(NN) = 2.76 and 5.02 TeV with the CMS detector. The results are compared with viscous hydrodynamic calculations using several different initial conditions, aswell asmicroscopic transport model calculations. None of the models provides a simultaneous description of the mixed higher-order flow harmonics and nonlinear response coefficients
The influence of using collapsed sub-processes and groups on the understandability of business process models
No full textMany factors influence the creation of business process models which are understandable for a target audience. Understandability of process models becomes more critical when size and complexity of the models increase. Using vertical modularization to decompose such models hierarchically into modules is considered to improve their understandability. To investigate this assumption, two experiments were conducted. The experiments involved 2 large-scale real-life business process models that were modeled using BPMN v2.0 (Business Process Model and Notation) in the form of collaboration diagrams. Each process was modeled in 3 modularity forms: fully-flattened, flattened where activities are clustered using BPMN groups, and modularized using separately viewed BPMN sub-processes. The objective was to investigate if and how different forms of modularity representation (used for vertical modularization) in BPMN collaboration diagrams influence the understandability of process models. In addition to the forms of modularity representation, the presentation medium (paper vs. computer) and model reader's level of business process modeling competency were investigated as factors that potentially influence model comprehension. 60 business practitioners from a large organization and 140 graduate students participated in our experiments. The results indicate that, when these three modularity representations are considered, it is best to present the model in a 'flattened' form (with or without the use of groups) and in the 'paper' format in order to optimally understand a BPMN model. The results also show that the model reader's business process modeling competency is an important factor of process model comprehension