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Changes in Tryptase Levels During Cardiac Surgery in Patients at Low Risk for Allergic Reactions
No full textTryptase test can be used as a clinical marker of mast cell activation. The present study is was aimed to identify variations in serum tryptase levels and their possible relationships with allergic reactions to protamine in low-risk patients undergoing cardiac bypass surgery. Thirty patients according to American Society of Anesthesiologists physical status III who underwent cardiac bypass surgery were enrolled. This prospective, non-randomised, clinical study was conducted in an operating room. Venous blood samples for tryptase measurements were obtained from cardiac bypass surgery patients upon admission to the operating room and immediately before and 30 min after the initiation of protamine administration. Signs of allergic reactions were recorded and management steps based on rapid effect response-based clinical assessments for diagnosis and treatment decisions during protamine administrations were described. Serum tryptase levels and clinical signs of allergic reactions, primarily mean arterial pressure (MAP), were recorded. Serum tryptase levels increased significantly and progressively during the bypass procedure (study power, 80%; sample size, 28; power of analysis, 99.8% with alpha=0.05); however, tryptase levels did not reach a sufficiently high level to confirm an allergic reaction. The MAP and heart rate decreased in 50% of the patients. Although tryptase increased significantly when compared with baseline levels, protamine-associated increases were not significant and failed to provide an unequivocal indication of an allergic response to protamine.institutional fund of Hatay Mustafa Kemal University, Turkey [12200]The study (study code: 12200) was supported by the institutional fund of Hatay Mustafa Kemal University, Turkey
A Highly Active and Stable Ru Catalyst for Syngas Production Via Glycerol Dry Reforming: Unraveling the Interplay Between Support Material and the Active Sites
No full textGlycerol dry reforming (GDR) was studied on Ru/La2O3, Ru/ZrO2, and Ru/La2O3-ZrO2 catalysts. Impacts of the support on morphological, electronic and surface chemical properties of the catalysts were comprehensively characterized by TEM, in-situ DRIFTS, XPS, ATR-IR and XRD. Initial (5 h) CO2 conversion at 750 C and CO2-to-glycerol ratio of 1-4 was ordered as Ru/La2O3 Ru/ZrO2 Ru/La2O3-ZrO2. During 72 h stability tests, Ru/ZrO2 deactivated by ~33% due to Ru sintering, structural deformation of the monoclinic zirconia support, and strong metal-support interaction. Under identical conditions, CO2 conversion on Ru/La2O3 decreased by 27% mainly due to dehydroxylation/carbonation of lanthana and severe coking. Lanthana-stabilized tetragonal zirconia phase of Ru/La2O3-ZrO(2 ; nbsp;)led to finely dispersed small oxidic Ru clusters which deactivated by 15% after 72 h and demonstrated unusually high catalytic performance that was on par with the significantly more expensive Rh-based catalysts, which are known with their exceptional activity and stability in GDR.Scientific and Technological Research Council of Turkey (TUBITAK) [117M163]; Bogazici University Research Fund [BAP-13880, BAP-16906]; Daiichi Kigenso Kagaku KogyoFinancial support for this work was provided by The Scientific and Technological Research Council of Turkey (TUBITAK, Grant number: 117M163) and by Bogazici University Research Fund (Grant numbers: BAP-13880 and BAP-16906) . Authors gratefully acknowledge Daiichi Kigenso Kagaku Kogyo, DKKK Company for kindly supplying the La2O3-ZrO2 support material used in the catalyst preparation. Authors thank to Prof. Alper Uzun for the useful discussions
A Capacitated Mobile Facility Location Problem With Mobile Demand: Recurrent Service Provision To En Route Refugees
No full text10th International Network Optimization Conference, INOC 2022 -- 7 June 2022 through 10 June 2022 -- 187074In this paper, we help humanitarian organizations provide service via mobile facilities (MFs) to migrating refugees, who attempt to cross international borders. Over a planning horizon, we aim to optimize number and routes and relocations of the MFs over a planning horizon. The problem is represented on a network where several refugee groups relocate in their predetermined paths throughout the periods. To incorporate continuity of service, each refugee group should be served at least once every fixed consecutive periods via capacitated MFs. We aim to minimize the total cost, consisting of fixed, service provision, and MF relocation costs, while ensuring the service continuity requirement. We formulate a mixed integer linear programming (MILP) model for this problem. We develop a matheuristic and an accelerated Benders decomposition algorithm as an exact solution method. The proposed model and solution methods are investigated over instances we extracted from the 2020 Honduras migration crisis. © 2022 Copyright held by the owner/authors(s).Türkiye Bilimsel ve Teknolojik Araştırma Kurumu, TÜBİTAK: 119M229Acknowledgment: This research is supported by TUBITAK [Grant number 119M229]
Avrupa Birliği ve Rusya Arasında Doğal Gaz Temelli Karşılıklı Bağımlılık İlişkisi: Sıkı Bağlardan Çözülmeye
No full textThis thesis focuses on the complex interdependence based on natural gas between the European Economic Community (EEC)/the European Union (EU) and the Union of Soviet Socialist Republics (USSR)/the Russian Federation (RF) via complex interdependence theory. The thesis has two main arguments. First of all, the conditions of complex interdependence took place in Europe between the EEC countries and the USSR in spite of the Cold War and the ideological competition between the two sides, and natural gas trade played a key role in this. The complex interdependence continued until the early 2000s in spite of structural changes such as the end of the Cold War and transformation of EEC into the EU due to overlapping reliable energy source need and reliable supplier quest of the EEC and USSR's need to establish economic relations with Europe. Secondly, in spite of the efforts of both sides, the complex interdependence gradually loosened after 2000 and cut with the invasion of Ukraine by the RF on 24 February 2022 because of five main developments. These developments are as follows: (1) EU's change of natural gas trade system where free market conditions and competition prevail, (2) Russian Federation's not being a contracting party to the Energy Charter Treaty, a European initiative, (3) EU's failure to develop a common market or common foreign policy strategy for natural gas, (4) Former Eastern Bloc countries centered crises negatively affecting natural gas trade between the EU and the RF and (5) Increasing role of North American LNG in global gas trade and changing the natural gas purchase and sale contracts in Europe. This thesis attempts to examine how the conditions establishing interdependence between the two sides with an asymmetrical interdependence in the context of natural gas occurred and how the non-state actors and interaction channels in both sides played a role in this process in two main time slots. It also attempts to examine the changes in the complex interdependence together with the rationales. It analyzes the course of relations between the EU, a natural gas consumer on a global scale, and the RF, a natural gas producer on a global scale as well, on the basis of complex interdependence with a focus on natural gas and the entire conditions of complex interdependence during the Cold War and the post-Cold War era. This bond continued and further strengthened until 2000 without being affected from systemic and sub-systemic changes in both sides, which led to significant changes in other fields.Bu tez, Avrupa Ekonomik Topluluğu (AET)/Avrupa Birliği (AB) ile Sovyet Sosyalist Cumhuriyetler Birliği (SSCB)/Rusya Federasyonu (RF) arasında doğal gaz temelli kurulan karşılıklı bağımlılık ilişkisine, karmaşık karşılıklı bağımlılık teorisi aracılığıyla odaklanmaktadır. Tezin iki temel argümanı vardır. İlk olarak, Avrupa'da Soğuk Savaş'a ve aralarındaki ideolojik rekabete rağmen, AET ülkeleri ile SSCB arasında karmaşık karşılıklı bağımlılık oluşmuş ve bunda da doğal gaz ticareti kayda değer rol oynamıştır. AET'nin güvenilir bir enerji kaynağı ihtiyacı ve güvenilir bir tedarikçi arayışı ile SSCB'nin Avrupa ile ekonomik ilişkiler kurma ihtiyacının örtüşmesiyle, Soğuk Savaş'ın sonu ve AET'nin AB'ne dönüşümü gibi yapısal değişikliklere rağmen karmaşık karşılıklı bağımlılık ilişkisi 2000'li yılların başına kadar sürmüştür. İkincisi, bu karmaşık karşılıklı bağımlılık, 2000 yılından sonra beş temel gelişme nedeniyle tarafların çabalarına rağmen tedricen çözülmüş ve nihayetinde RF'nin Ukrayna'yı işgaliyle 24 Şubat 2022 tarihinde kopmuştur. Bu gelişmeler şunlardır: (1) AB'nin doğal gaz ticaretinde serbest piyasa koşullarına ve rekabete dayalı sisteme geçmesi, (2) RF'nin Avrupa girişimi olan Enerji Şartı Antlaşması'nı taraf olmaması, (3) AB'nin doğal gaz alanında ortak pazar veya ortak dış politika stratejisi geliştirememesi, (4) Eski Doğu Bloğu ülkeleri merkezli krizlerin AB-RF doğal gaz ticaretini olumsuz etkilemesi ve (5) Kuzey Amerika menşeili LNG'nin küresel doğal gaz ticaretindeki rolünün artması ve Avrupa'daki doğal gaz alım ve satım sözleşme yapılarını değiştirmesi. Bu tez özellikle, doğal gaz bağlamında aralarında asimetrik bir karşılıklı bağımlılık bulunan iki taraf arasında, bu bağımlılığı oluşturan koşulların nasıl tesis edildiğini ve her iki taraftaki devlet dışı aktörler ile etkileşim kanallarının bu süreçte nasıl rol oynadıklarını, iki ana zaman diliminde incelemeyi ve iki taraf arasındaki karmaşık karşılıklı bağımlılığın geçirdiği değişimi gerekçeleriyle irdelemeyi hedeflemektedir
Bioinspired Collagen/Gelatin Nanopillared Films as a Potential Implant Coating Material
No full textCollagen-based Sharpey's fibers are naturally located between alveolar bone and tooth, and they have critical roles in a well-functioning tooth such as mechanical stability, facile differentiation, and disease protection. The success of Sharpey's fibers in these important roles is due to their unique location, vertical alignment with respect to tooth surface, as well as their micronanofiber architecture. Inspired by these structures, herein, we introduce the use of nanoporous anodic aluminum oxide molds in a drop-casting setup to fabricate biopolymeric films possessing arrays of uniform Collagen: Gelatin (Col:Gel) nanopillars. Obtained structures have diameters of similar to 90 nm and heights of similar to 300 nm, yielding significantly higher surface roughness values compared to their flat counterparts. More importantly, the nanostructures were parallel to each other but perpendicular to the underlying film surface imitating the natural collagenous structures of Sharpey's fibers regarding nanoscale morphology, geometrical orientation, as well as biochemical content. Viability testing showed that the nanopillared Col:Gel films have high cell viabilities (over 90%), and they display significantly improved attachment (ca.similar to 2 times) and mineralization for Saos-2 cells when compared to flat Col:Gel films and Tissue Culture Polystyrene (TCPS) controls, plausibly due to their largely increased surface roughness and area. Hence, such Sharpey's fiber-inspired bioactive nanopillared Col:Gel films can be used as a dental implant coating material or tissue engineering platform with enhanced cellular and osteogenic properties.Turkish Academy of Sciences (TUBA)We thank Prof. Dr. Gokhan Demirel from Gazi University Chemistry Department for FTIR measurements. This study was supported by the Turkish Academy of Sciences (TUBA)
Performance of the Atlas Level-1 Topological Trigger in Run 2
No full textDuring LHC Run 2 (2015-2018) the ATLAS Level-1 topological trigger allowed efficient data-taking by the ATLAS experiment at luminosities up to 2.1 x10(34) cm(-2) s(-1), which exceeds the design value by a factor of two. The system was installed in 2016 and operated in 2017 and 2018. It uses Field Programmable Gate Array processors to select interesting events by placing kinematic and angular requirements on electromagnetic clusters, jets, tau-leptons, muons and the missing transverse energy. It allowed to significantly improve the background event rejection and signal event acceptance, in particular for Higgs and B-physics processes
Time-Varying Effect of Uncertainty Shocks on Unemployment
No full textWe examine the dynamic effects of uncertainty shocks on unemployment during recessions in the US. We estimate a Bayesian time-varying parameter structural vector autoregression. We analyze how the impact of uncertainty shocks on U.S. unemployment changes over time. We find that uncertainty shocks have both higher unit impact and higher total effect on unemployment during the Great Recession compared to those of previous recessions. Different characteristics of the Great Recession amplify the effect of uncertainty on unemployment. Two channels distinguish the Great Recession from other recessions: the federal funds rate hitting the zero lower bound and financial frictions. We find that these factors are significant determinants of the time-varying relationship between unemployment and uncertainty. Robustness analyses with alternative measures of uncertainty and alternative empirical specifications validate the results of the paper. © 2022 Elsevier B.V
On a Type-2 Fuzzy Approach To Solution of Second-Order Initial Value Problem
No full textIn this paper, we have proposed a new representation of the triangular type-2 fuzzy numbers called the perfect triangular type-2 fuzzy numbers and defined their level sets by the (alpha, beta)-cut representation. With respect to this (alpha, beta)-cut representation, we have defined the algebraic operations for perfect triangular type-2 fuzzy numbers by using interval arithmetics. And then, we have proposed a method to find the solutions for second-order initial value problems with perfect triangular type-2 fuzzy initial conditions and forcing coefficients based on the Zadeh's extension principle. Finally, we have used the proposed method for the mechanical vibration and RLC circuit models with perfect triangular type-2 fuzzy numbers