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A deterministic and stochastic assessment for exposure and risk of arsenic via ingestion of edible crops
No full textNatural arsenic contamination is a critical problem for various places around the world. Simav Plain (Kutahya, Turkey) is one such area that was shown to have natural arsenic contamination in its waters and soils. Arsenic exposure through ingestion of edible crops cultivated in Simav Plain and associated health risks were assessed in this study. To achieve this objective, arsenic levels in 18 crop species were estimated based on measured soil arsenic concentrations. Individual and aggregate non-carcinogenic and carcinogenic risks associated with ingestion of arsenic-contaminated crops were then assessed with scenario-based deterministic point estimates and stochastic population estimates. Monte Carlo simulation was used for the estimation of population health risks. Accordingly, wheat was found as the highest-ranked crop specie for the both types of health risks, followed by tomato and potato, which are three of the most consumed crops in the region. The risk levels estimated in this study were relatively high, indicating consumption of crops grown in the plain may be posing significant health risks even at lower-bound estimates. Consuming wheat, tomato, potato, and their products from uncontaminated sources was found to reduce the aggregate risks up to 88% implicating the importance of proposing suitable management measures for similar risk-prone areas
Pomza ve nSDD-Pomza ile sabit yataklı kolon reaktörde metilen mavisi giderimi: Deneysel ve modelleme çalışması
No full textNano zero-valent iron (nZVI) emerges as a low cost and eco-friendly adsorbent to treat textile wastewater, which is rich in dye content. However nZVI particles can easily agglomerate in aqueous environment due to electrostatic interaction, decreasing their treatment efficiency. Therefore pumice, a low-cost and naturally found porous material with lower specific surface area (2m2/gr), can be used as support material to reduce agglomeration of nZVI. Treatment efficiencies of pumice/nZVI packing (10:0 and 9:1 (w/w)) in column reactor for specified initial methylene blue concentrations (25, 50, 75 and 100 mg/L) were investigated in this study. Adsorption capacities of the adsorbents were calculated as 2.8 and 4.2 mg/g-adsorbent, respectively at 100 mg/L initial methylene blue concentration. Mixed bed column performed significantly better than its pumice-only counterpart for low initial concentrations. Thomas adsorption model was applied to experimental results with a moderate to high predictive power.Nano sıfır değerlikli demir (nSDD) yüksek renk konsantrasyonlarına sahip tekstil atıksularının arıtımında ekonomik ve çevre dostu bir adsorban olarak ortaya çıkmaktadır. Ancak nSDD partikülleri sulu çözeltilerde elektrostatik etkileşimler sebebiyle kolayca topaklaşmakta ve bu da arıtma veriminin düşmesine neden olmaktadır. Dolayısıyla düşük maliyetli, doğal poröz yapıda ve ortalama 2m2/gr spesifik yüzey alanına sahip pomza, nSDD topaklaşmasını önleyici bir malzeme olarak kullanılabilir. Bu çalışmada sadece pomza ve pomza-nSDD (ağırlıkça 9:1) karışımının kullanıldığı kolon reaktörde 25, 50, 75 ve 100 mg/L metilen mavisi konsantrasyonları için arıtma verimleri incelenmiştir. Pomzanın ve pomza-nSDD karışımının 100 mg/L metilen mavisi deneyindeki toplam kapasiteleri sırasıyla 2,8 ve 4,2 mg/g-adsorban olarak bulunmuştur. Özellikle düşük konsantrasyonlarda, pomza-nSDD karışımının arıtma performansını önemli ölçüde arttırdığı görülmüştür. Thomas modeli deneysel verilere uygulanmış ve modelin öngörü gücünün düşük konsantrasyonda yüksekken, yüksek konsantrasyonlarda ortalama olduğu kanısına varılmıştır
Combinations of single-top-quark production cross-section measurements and |f LV Vtb| determinations at √s = 7 and 8 TeV with the ATLAS and CMS experiments
No full textThis paper presents the combinations of single-top-quark production cross-section measurements by the ATLAS and CMS Collaborations, using data from LHC proton-proton collisions at = 7 and 8 TeV corresponding to integrated luminosities of 1.17 to 5.1 fb(-1) at = 7 TeV and 12.2 to 20.3 fb(-1) at = 8 TeV. These combinations are performed per centre-of-mass energy and for each production mode: t-channel, tW, and s-channel. The combined t-channel cross-sections are 67.5 +/- 5.7 pb and 87.7 +/- 5.8 pb at = 7 and 8 TeV respectively. The combined tW cross-sections are 16.3 +/- 4.1 pb and 23.1 +/- 3.6 pb at = 7 and 8 TeV respectively. For the s-channel cross-section, the combination yields 4.9 +/- 1.4 pb at = 8 TeV. The square of the magnitude of the CKM matrix element V-tb multiplied by a form factor f(LV) is determined for each production mode and centre-of-mass energy, using the ratio of the measured cross-section to its theoretical prediction. It is assumed that the top-quark-related CKM matrix elements obey the relation |V-td|, |V-ts| << |V-tb|. All the |f(LV)V(tb)|(2) determinations, extracted from individual ratios at = 7 and 8 TeV, are combined, resulting in |f(LV)V(tb)| = 1.02 +/- 0.04 (meas.) +/- 0.02 (theo.). All combined measurements are consistent with their corresponding Standard Model predictions
Can tube tunnel crossings relieve urban congestion problems? Izmir tube tunnel project proposal under scrutiny
No full textBuilding underwater tube tunnel crossings to ease the urban congestion problems has become a popular approach for many cities across the globe. London, New York, Istanbul, Hamburg, Sydney and Brisbane are among these cities. However, the effectiveness and externalities of these expensive mega urban infrastructures have also been questioned widely among urban, transport and environmental planning scholars. Given the international popularity of the topic, this study places a new tube tunnel crossings project from Izmir, Turkey under the microscope. In this heuristic simulation study, policy-on scenarios were tested to determine possible impacts of the underwater tube tunnel-crossing project. The traffic impacts are discussed using simulations assigning the initial origin-destination data. The results of the study revealed that, given the two locations, outer and inner locations over the dagger-shape bay, the capacity increments on the bridge links and the links around the periphery highway did not bring any effective solutions beyond some minor improvements. The findings disclosed that the ineffectiveness of the tube tunnel crossing might be due to the excessive congestion happening all over the downtown area, which clogs the passageways to the bridge. The paper highlights the limitations of the tube tunnel-crossing project, emphasises the need for comprehensive investigations before committing to the project and advocates the emphasis to be actually given for sustainable mobility
Measurement of the top quark polarization and t¯t spin correlations using dilepton final states in proton-proton collisions at √s=13 TeV
No full textMeasurements of the top quark polarization and top quark pair (t (t) over bar) spin correlations are presented using events containing two oppositely charged leptons (e(+)e(-), e(+/-)mu(-/+), or mu(+)mu(-)) produced in proton-proton collisions at a center-of-mass energy of 13 TeV. The data were recorded by the CMS experiment at the LHC in 2016 and correspond to an integrated luminosity of 35.9 fb(-1) . A set of parton-level normalized differential cross sections, sensitive to each of the independent coefficients of the spin-dependent parts of the t (t) over bar production density matrix, is measured for the first time at 13 TeV. The measured distributions and extracted coefficients are compared with standard model predictions from simulations at next-to-leading-order (NLO) accuracy in quantum chromodynamics (QCD), and from NLO QCD calculations including electroweak corrections. All measurements are found to be consistent with the expectations of the standard model. The normalized differential cross sections are used in fits to constrain the anomalous chromomagnetic and chromoelectric dipole moments of the top quark to -0.24 < C-tG/Lambda(2) < 0.07 TeV-2 and -0.33 < C-tG(I)/Lambda(2) < 0.20 TeV-2, respectively, at the 95% confidence level
Dış sofalı geleneksel yapılarda ısıl iyileştirmeler: Kentsel ve kırsal Muğla konutları
No full textThesis (Doctoral)--Izmir Institute of Technology, Architectural Restoration, Izmir, 2019Includes bibliographical references (leaves: 166-184)Text in English; Abstract: Turkish and EnglishSustaining functional continuity of historical buildings is a commonly acknowledged conservation strategy and thermal retrofitting interventions applied on these buildings has complemental potentials to this strategy as these interventions can be designed to increase the thermal satisfaction of occupants. The aim of this thesis is to examine the thermal behavior of a common historical building type in Anatolia, the traditional houses with exterior hall, and to determine enhancement potentials of possible thermal interventions which will not cause loss of heritage values. Method of the study consists of on-site thermal measurements and transient thermal analysis of case studies utilizing the software DesignBuilder. Case studies were selected from both urban and rural sub-settlements of Muğla City in order to detect possible effects of prevailing microclimates. With the results obtained, it was demonstrated the retrofitting interventions of thermal insulation works in roofs and floors between storeys, airtightness measures, addition of secondary glazing to window frames and the addition of closed circulation corridors provide significant improvements in thermal performance of the cases. According to simulation analyses, it was specified that these interventions would save 38.0% of the total building energy use in the urban and 49.4% in the rural subsettlements. These improvement percentages can even be increased to more than 80% when the integration of a new HVAC system such as ground-source heat pump is implemented. Consequently, it was determined the traditional houses with exterior hall have significant potentials for thermal enhancements which renders the application of thermal interventions as a capable conservation strategy.Tarihi yapıların işlevsel sürekliliğinin sağlanması için önlemler alınması,
restorasyon uygulamalarında yaygın olarak kullanılan önemli bir koruma stratejisidir. Bu
yapılar için önerilecek ısıl iyileştirme müdahaleleri ise yapı enerji kullanımında tasarruf
ve kullanıcı ısıl konforunda iyileşme sağlayarak bu strateji bağlamında tamamlayıcı
potansiyellere sahiptir. Bu tezin amacı, Anadolu’da yaygın bir tarihi yapı tipi olan dış
sofalı geleneksel konutların ısıl davranışını incelemek ve bu incelemeye dayalı olarak bu
tür yapıların miras değerinde kayıplara neden olmayacak olası ısıl müdahalelerin
iyileştirme potansiyellerini belirlemektir. Çalışmanın yöntemi, örnek yapılarda
uygulanmış yerinde ısıl ölçümlerden ve yapıların DesignBuilder yapı simülasyon
yazılımı kullanılarak yürütülmüş zamana bağlı ısıl analizlerinden oluşmaktadır. Örnek
yapılar, olası mikroklima koşullarının etkilerinin de değerlendirilebilmesi için Muğla
Kenti’nin kentsel ve kırsal alt yerleşmelerinden seçilmiştir. Elde edilen ısıl simülasyon
sonuçlarıyla, çatıda ve katlar arası döşemelerde uygulanacak ısıl yalıtım uygulamalarının,
hava sızdırmazlık önlemlerinin, pencerelere çift cam eklenmesinin ve özgün durumda
doğrudan dış hava koşullarına açılan odaların kapalı bir dolaşım koridoruyla birbirine
bağlanmasının yapıların ısıl performansında önemli iyileştirmeler sağladığı
gösterilmiştir. Bu müdahalelerin birlikte uygulandığında, kentsel alt yerleşme için bina
toplam enerji kullanımında % 38.0, kırsal alt yerleşmede ise % 49.4 oranında tasarruf
sağladığı belirlenmiştir. Bu iyileştirme yüzdelerinin, yapılarda toprak kaynaklı ısı
pompası gibi yüksek verimli bir ısıtma / soğutma sisteminin entegrasyonu da
sağlanabildiğinde % 80’in üstüne çıkabildiği görülmüştür. Sonuç olarak, dış sofalı
geleneksel Anadolu konutunun ısıl iyileştirme konusunda önemli bir potansiyele sahip
olduğu ve bu türden iyileştirmeleri sağlayabilecek olası müdahalelerin de etkili bir
koruma stratejisi olarak değerlendirilmesi gerektiği belirtilmiştir
Constraints on anomalous HVV couplings from the production of Higgs bosons decaying to τ lepton pairs
No full textA study is presented of anomalous HVV interactions of the Higgs boson, including its CP properties. The study uses Higgs boson candidates produced mainly in vector boson fusion and gluon fusion that subsequently decay to a pair of tau leptons. The data were recorded by the CMS experiment at the LHC in 2016 at a center-of-mass energy of 13 TeV and correspond to an integrated luminosity of 35.9 fb(-1). A matrix element technique is employed for the analysis of anomalous interactions. The results are combined with those from the H -> 4l decay channel presented earlier, yielding the most stringent constraints on anomalous Higgs boson couplings to electroweak vector bosons expressed as effective cross section fractions and phases: the CP-violating parameter f(a3) cos(phi(a3)) = (0.00 +/- 0.27) x 10(-3) and the CP-conserving parameters f(a2) cos(phi(a2)) = (0.08)(-0.21)(+1.04)) x 10(-3), f(Lambda 1) cos(phi(Lambda 1)) = (0.00)(-0.09)(+0.53)) x 10(-3), and f(Lambda 1)(Z gamma) cos(phi(Z gamma)(Lambda 1)) = (0.0(-1.3)(+1.1)) x 10(-3). The current dataset does not allow for precise constraints on CP properties in the gluon fusion process. The results are consistent with standard model expectations
The injection of CO2 to hypersaline geothermal brine: A case study for Tuzla region
No full textScaling is a serious issue for geothermal power plants since it remarkably decreases the harvesting of energy. The reduction of pH by organic acids whose structure is close to CO2 for instance formic acid has been an effective solution for the minimization of scaling. Herein, the effect of CO2 injection on the formation of scaling particularly metal-silicates was investigated for the model case of Tuzla Geothermal Field (TGF) located in the northwest of Turkey. CO2 has an acidic character in aqueous systems because it leads to the formation of carbonic acid. The injection of 20.6 m(3)/s CO2 (approximately 88 ppm) to hypersaline brine of TGF is a promising green approach for both mitigation of scaling by reducing pH from 7.2 to 6.2 at the well-head and the minimization of potential corrosion compared to the use of formic acid (55 ppm)
İzmir'de gıda sanayisinin yer seçimi
No full textThesis (Master)--Izmir Institute of Technology, City and Regional Planning, Izmir, 2019Includes bibliographical references (leaves: 43-47)Text in English; Abstract: Turkish and EnglishIn this study, the spatial distribution of the food companies registered in the Aegean Region Chamber of Industry in İzmir has been investigated and the causality of the site selection has been reviewed. The empirical studies conducted in the literature so far does not include a detailed study on the choice of location of the food industry, a factor that adds strength to this study. The purpose of the current study is to analyse the determinants of firm location in Izmir’s food industry. It particularly focuses on the impact of experience and size of the firms. In this study, we examined, through statistical methods (such as descriptive statistics, maps, cross sectional linear regressions, spatial autocorrelation analyses), 734 companies. The following variables were empirically analysed, firms’ establishment dates, sub-sectors, number of employees, capital assets, locations, distances from the centre of Izmir, distances from the centre of the sub-province that the establishment belongs to and the distance from each other. As a result of the empirical analyses and spatial data evaluation, companies’ choice of location in the food industry can be summarized as follows; Experience plays a very significant role, which means that experienced companies are located in the centre or close to the centre because they have already been well-established in that place. The choice of location does not have any bearing upon the size of the firm.Bu çalışmada gıda sanayi özelinde, İzmir genelinde, Ege Bölgesi Sanayi Odası’na kayıtlı firmaların mekansal dağılımlarına bakılarak, yer seçimlerinin nedensellikleri araştırılmıştır. Şimdiye kadar yapılan empirik araştırmalar arasında Kent Ekonomisi literatüründe yer alarak, gıda sanayinin yer seçimi özelinde yapılan detaylı bir araştırma bulunmaması bu çalışmayı güçlü kılmaktadır. Çalışmanın amacı, İzmir’deki gıda sanayi firmalarının yer seçim davranışını ampirik olarak incelemek ve yer seçimi belirleyicilerini tespit etmektir. Özellikle, firmaların büyüklüğü (istihdam ve sermaye bakımından) ve deneyimi odak değişkenler olmuştur. Çalışma alanı olarak 734 gıda firmasının kuruluş tarihleri, alt sektörleri, çalışan sayıları, sermaye miktarları, konumları, İzmir merkeze uzaklıkları, bulunduğu ilçe merkezine olan uzaklıkları ve birbirlerine olan uzaklıkları gibi değişkenler çeşitli istatistiksel yöntemlerle (betimleyici istatistikler, haritalar, yatay kesit lineer regresyon analizleri, mekansal korelasyon analizi) incelenmiştir. Elde edilen empirik analizler ve mekansal veriler sonunda; gıda sanayinin yer seçiminde firmaların; deneyimlerine göre konumlandıkları görülmüştür. Bunun anlamı, deneyimli firmalar daha önceden yer aldıkları için merkeze yakın ya da merkezde bulunma şansını elde ederler. Deneyim ile merkeze uzaklık arasında istatistiki olarak anlamlı ve negatif bir ilişki saptanmıştır. Yer Seçimi firmanın ölçeğine ve büyüklüğüne bağlı değişmemektedir. İlgili değişken istatistiki olarak anlamlı bulunmamıştır
Endüstriyel biyokataliz için termofilik P450 tasarımında biyoinformatik temelli yaklaşım
No full textThesis (Master)--Izmir Institute of Technology. Biotechnology and Bioengineering, Izmir, 2019Includes bibliographical references (leaves: 91-101)Text in English; Abstract: Turkish and EnglishEnzyme catalyzed biosynthesis of steroidal drugs is an important process for pharmaceutical manufacturing. Cytochrome P450 (P450) monooxygenases are important for hydroxylation of steroid structures because they can catalyze the oxidation of inactive carbon bonds with high selectivity and efficiency. CYP119 is an acidothermophilic P450 from Sulfolobus acidocaldarius, which has the potential to be used as biocatalyst for industrial production since it shows activity at high temperature and low pH conditions. In this work we aim to use CYP119 for selective hydroxylation of progesterone, which is not the original substrate of CYP119, for production of precursor molecules of important hormones like cortisone and aldosterone. Crystal structure of CYP119 (PDB ID: 1F4T) was used for selecting residues that were mutated according to structural alignment with other CYPs that can catalyze progesterone hydroxylation naturally. Progesterone-docking performed with CYP119 to identify residues that create clashes with substrate. Finally selected 12 residues (Leu69, Val151, Phe153, Leu155, Leu205, Ile208, Ala209, Thr213, Thr214, Val254, Thr257, Leu354) were mutated with PyRosetta program to Gly, Glu, Phe, Met, Ala, His, Arg and Ile. Progesterone-docking performed with using DockMCM Protocol of PyRosetta. We used two different starting coordinates of progesterone for docking and results were eliminated according to their energy scores. Best mutants were used for creating double/triple mutants and second round of docking and elimination process were performed with using double/triple mutant enzymes. Final number of 11 mutants with best scores were selected and their possible products were identified.Steroid temelli ilaçların enzim katalizli biyosentezi farmasötik üretimi için önemli
bir süreçtir. Sitokrom P450 (P450) monooksijenazlar inaktif karbon bağlarının
oksidasyonunu yüksek seçicilik ve etkinlikle katalizleyebildikleri için steroid yapıların
hidroksilasyonu açısından önemlilerdir. Asidoterfomilik bir arkea olan Sulfolobus
acidocalderius’tan elde edilen CYP119, yüksek sıcaklık ve düşük pH koşullarında
aktivite gösterdiği için endüstriyel üretimde biyokatalist olarak kullanılma potansiyeline
sahiptir. Bu çalışmada CYP119 kullanılarak orijinal substratı olmayan progesteron
hormonunun seçici hidroksilasyonuyla, aldosteron ve kortizon gibi önemli hormonların
öncül moleküllerinin üretimi amaçlanmıştır. Doğal olarak progesteron hidroksilasyonunu
katalizleyen CYPlerle yapılacak yapısal hizalanma sonucu mutasyona uğratılacak
aminoasitlerin belirlenmesi için CYP119’un kristal yapısı (PDB NO: 1F4T)
kullanılmıştır. Substratla çakışma veren amino asitleri belirlemek için CYP119 enzimine
progesteron yerleştirme yapılmıştır. Finalde seçilen 12 amino asit (Leu69, Val151,
Phe153, Leu155, Leu205, Ile208, Ala209, Thr213, Thr214, Val254, Thr257, Leu354),
PyRosetta program kullanılarak Gly, Glu, Phe, Met, Ala, His, Arg ve Ile amino asitleriyle
mutasyona uğratılmıştır. Progesteron yerleştirme için PyRosetta programının DockMCM
protokolü uygulanmıştır. Yerleştirme için iki farklı progesteron başlangıç koordinatı
kullanılmış ve sonuçlar enerji değerlerine göre elenmiştir. En iyi mutantlar ikili/üçlü
mutasyonları oluşturmak için kullanılmış ve yerleştirme ve eleme işleminin ikinci etabı
ikili/üçlü mutantlar kullanılarak gerçekleştirilmiştir. Finalde en iyi sonuç veren 11 mutant
seçilmiş ve olası ürünleri belirlenmiştir