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Citation Count: 0
"2-pirazolin yapısındaki yeni bir bileşiğin sentezi, moleküler modellemesi ve monoaminoksidaz inhibitörü etkisinin araştırılması"
(Türkiye Halk Sağlığı Kurumu, 2018) Yelekçi, Kemal; Uçar, Gülberk; Yelekçi, Kemal
Amaç: Nöromediatörlerin yıkımından sorumlu olan monoamin oksidaz (MAO) enziminin izoformlarının (MAO-A ve -B) birçok hastalık ile yakından ilişkili olduğu; MAO inhibitörlerinin depresyon, Parkinson ve Alzheimer hastalığı gibi hastalıkların tedavisinde kullanıldığı bilinmektedir. Grubumuzca daha etkin, tersinir ve az yan etkili yeni bir MAO inhibitörü (SH2U bileşiği) sentezlenmiş ve bu bileşiğin insan MAO enzimini (hMAO) inhibe etme yeteneği incelenmiştir. Ayrıca bu yeni bileşiğin hMAO ile etkileşimi, moleküler modelleme çalışmaları ile detaylı bir şekilde araştırılmıştır. Sentezlenen yeni bileşiğin hMAO’yu kuvvetli bir şekilde yarışmalı ve tersinir olarak inhibe ettiği bulunmuştur. Söz konusu bileşiğin Parkinson ve Alzheimer hastalıklarının tedavisinde ümit verici bir ilaç etken maddesi olabileceği düşünülmektedir. Yöntem: 3’,5’-Dikloro-2’-hidroksi asetofenon ile p-tolualdehit’in metanol içinde KOH varlığında reaksiyona girmesiyle 1-(3,5-dikloro-2-hidroksifenil)- 3-p-tolil prop-2-en-1-on (3’,5’-Dikloro-2’-hidroksi-4- metil şalkon) bileşiği sentez edilmiştir. Daha sonra elde edilen bu bileşiğin etanol içerisinde geri çeviren soğutucu altında izonikotinik asit hidrazit ile muamele edilmesiyle [3-(3,5-dikloro-2-hidroksifenil)-5-p-tolil-4,5- dihidropirazol-1-il] (piridin-4-il) metanon bileşiği sentez edilmiştir. Yapısı doğrulanan bu bileşiğin hMAO enzimi ile etkileşimi, ticari tayin kiti kullanılarak fluorometrik bir yöntemle incelenmiştir. Ayrıca, söz konusu yeni bileşik ile hMAO arasındaki etkileşimler, moleküler modelleme çalışmaları ile aydınlatılmıştır. Bulgular: Sentezlenen bileşiğin yapısı, IR, Mass, 1H-NMR ve elemental analiz yöntemleri kullanılarak doğrulanmıştır. Yapısı doğrulanan bu bileşiğin etkin, seçici, tersinir, toksik olmayan bir hMAO-B inhibitörü olduğu ve inhibisyonun yarışmalı olduğu görülmüştür. Moleküler yerleştirme programı kullanılarak bileşiğin hMAO-B enziminin aktif bölgesinde hangi amino asit yan zincirleri ile ne tür girişimleri yaptığı belirlenmiştir. Sonuç: Yeni sentezlenen SH2U bileşiği, hMAO-B enzimini kuvvetle, seçici, yarışmalı ve tersinir olarak inhibe etmiştir. Sentezlediğimiz bileşik, bilinen seçici ama tersinmez MAO-B inhibitörü olan selejilin’den daha etkin ve seçici, tersinir olarak hMAO-B enzimini inhibe etmiştir ve Parkinson ile Alzheimer hastalığı tedavisinde kullanılabilecek bir ilaç etken maddesi olarak ümit vadetmektedir.
Citation Count: 0
The Association of Gvhd With Hla Dr Alleles, Ifn-Gamma, Tgf-Beta, And Mbl2 Gene Polymorphism
(Wiley, 2019) Oğuz, Rusdu; Çiftçi, Hayriye Şentürk; Gökçe, Muge; Öğret, Yeliz; Karadeniz, Sedat Tanju; Pehlivan, Sacide; Aydın, Filiz
[Abstract Not Available]
Citation Count: 1
A Bayesian approach to developing a strategic early warning system for the French milk market
(Halmstad University, 2017) Bisson, Christophe; Gürpınar, Furkan
A new approach is provided in our paper for creating a strategic early warning system allowing the estimation of the future state of the milk market as scenarios. This is in line with the recent call from the EU commission for tools that help to better address such a highly volatile market. We applied different multivariate time series regression and Bayesian networks on a pre-determined map of relations between macro-economic indicators. The evaluation of our findings with root mean square error (RMSE) performance score enhances the robustness of the prediction model constructed. Our model could be used by competitive intelligence teams to obtain sharper scenarios, leading companies and public organisations to better anticipate market changes and make more robust decisions.
Citation Count: 4
Broadband Equalizer Design with Commensurate Transmission Lines via Reflectance Modeling
(IEICE-INST ELECTRONICS INFORMATION COMMUNICATIONS ENG, 2008) Şengül, Metin Y.; Yarman, Sıddık Binboğa
In this paper an alternative approach is presented to design equalizers (or matching networks) with commensurate (or equal length) transmission lines. The new method automatically yields the matching network topology with characteristic impedances of the commensurate lines. In the implementation process of the new technique first the driving point impedance data of the matching network is generated by tracing a pre-selected transducer power gain shape without optimization. Then it is modelled its it realizable bounded-real input reflection coefficient in Richard domain which ill turn yields the desired equalizer topology with line characteristic impedances. This process results in an excellent initial design for the commercially available computer aided design (CAD) packages to generate final circuit layout for fabrication. An example is given to illustrate the utilization of the new method. It is expected that the proposed design technique is employed as it front-end to commercially available computer aided design (CAD) packages which generate the actual equalizer circuit layout with physical dimensions for mass production.
Citation Count: 10
Competitive intelligence and information technology adoption of SMEs in Turkey: Diagnosing current performance and identifying barriers
(Halmstad University, 2013) Wright, Sheila; Bisson, Christophe; Duffy, Alistair P.
The need for SMEs to behave in a more concise and coherent competitive fashion is well recognised. This study reports on an empirical study of SMEs in Turkey. Their responses were applied to a behavioural and information technology adoption framework which enabled the identification of areas where changes would be required for these firms to begin operating at a higher level of competence. The findings revealed significant scope for improvements on all strands of the diagnostic framework: attitude gathering location technology support IT systems support and finally use of intelligence-based output by decision-makers. Through free form responses it was also possible to identify barrier to higher level adoption and performance inhibiters which were subsequently categorised and assessed for significance.
Citation Count: 0
Considerations and Confusions about theRegulatory Focus Theory and a Future Agendafor Researchers in Marketing
(Boğaziçi Üniversitesi, İktisadi ve İdari Bilimler Fakültesi, 2017) Merdin-Uygur, Ezgi
The regulatory focus theory is the mark of a paradigm shift away from a unidimensional hedonism towards a multiplicity of regulatory foci. It possesses great explanatory power; however a lot remains unresolved despite a promising body of empirical work. This paper highlights various considerations concerning the conceptual and comparative qualities of the regulatory focus theory. The discussion moves into the intersection of regulatory focus and consumer behavior literature, briefly summarizing the findings and followed by a number of propositions to be tested for future research.
Citation Count: 4
Design and implementation of a negative feedback oscillator circuit based on a Cellular Neural Network with an Opposite Sign Template
(2010) Özmen, Atilla; Tander, Baran; Özçelep, Yasin
In this paper explicit amplitude and frequency expressions for a Cellular Neural Network with an Opposite-Sign Template (CNN-OST) under oscillation condition are derived and a novel inductorless oscillator circuit with negative feedbacks based on this simple structure is designed and implemented. The system is capable of generating quasi-sine signals with tuneable amplitude and frequency which can't be provided at the same time in the classical oscillator circuits.
Citation Count: 3
Elasticity Study of PAAm-kappa C Composite Prepared in Various kappa C Content and Measured at Several Temperatures
(Polish Acad Sciences Inst Physics, 2015) Evingür, Gülşen Akin; Pekcan, Önder
Polyacrylamide (PAAm)-kappa carrageenan (kappa C) composite gels were prepared via free radical crosslinking copolymerization with various (w/v) percentages of kappa C in the range between 0.5 and 3 (w/v)% of kappa C . Elasticity properties such as stress strain and compressive elastic modulus S of these composite gels were studied in various kappa C content and at several temperatures. The content and temperature dependence of the compressive elastic modulus S of the swollen PAAm-kappa C composite gels due to volume phase transition were produced by using tensile testing technique. It is understood that the compressive elastic modulus was found to decrease up to 1 (w/v)% of kappa C and then increase by increasing kappa C contents at constant temperatures. The composite preserves the ability to undergo the volume phase transition and its compressive elastic modulus is found to be strongly dependent on the kappa C content and temperature. It is observed that the compressive elastic modulus increased when temperature is increased up to 40 degrees C and then decreases below this temperature for all composite gels. However PAAm-kappa C composite gel presented lower values for the compressive elastic modulus showing a minima at 40 degrees C for 1 (w/v)% of kappa C content gel.
Citation Count: 11
Exploring competitive intelligence practices of French local public agricultural organisations
(Halmstad University, 2014) Bisson, Christophe
Modern agriculture has increased the need for information when making strategic decisions for farmers since they must be more entrepreneurial to survive. This paper investigates the levels of Competitive Intelligence practices in a French Regional Chamber of Agriculture and its four Departmental Chambers of Agriculture to examine the ability of these public organisations to keep fulfilling one of their missions which is to provide the necessary information and knowledge to farmers. Thus this study proposes a behavioural and operational typology of Competitive Intelligence practice. Both types of organisations demonstrate that they are not well adapted to support the entrepreneurial farmers on this issue. The findings of this study and the diagnosis of the Competitive Intelligence practices applied to the typology could be of help to increase their and other public agricultural structures performance levels. Furthermore the platform has the potential to inspire the public sector through subsequent adaptations.
Citation Count: 1
Exploring switching factors for mobile number portability: A survey
(Inst Advanced Science Extension, 2017) Khaliq, Imran Hameed; Mahmood, Hafiz Zahid; Malik, Summaira; Jan, Malik Jahangir; Zameer, Asif
Pakistan's mobile phone market is one of the world's fastest growing markets with a subscriber base of 137 million users. Competition in the country's telecommunication industry is dominated by four players and customer demand is high. In addition Pakistan is the first country in South Asia to have implemented Mobile Number Portability (MNP) in March 2007. MNP is a facility that allows mobile subscribers to switch between service providers without changing their existing phone numbers. Mobile phone service provider's selection may be influenced by various factors. Therefore this research was undertaken to explore factors affecting MNP and to determine which factors were most influential in the selection of mobile phone service providers in a developing economy like Pakistan. Moreover the study also probed into differences in customer perceptions between pre-paid and post-paid customers. This exploratory study is based on primary data collected from 300 customers using services of different cellular companies who had experienced MNP facility. Factor analysis was carried out on obtained data and reliability of the resultant scale was verified to achieve the objectives of the study. The outcome of this research provided a concise framework of the various dimensions of customer choice. Contrary to previous researches the result of this study indicated that infrastructural services customer relationships call quality and promotional packages were the most important factors affecting MNP. However price of services was found less important factor in selection of telecommunication service providers. This study also showed that pre-paid and post-paid customers can be significantly different for many value-added services and promotional tools. (C) 2017 The Authors. Published by IASE. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
Citation Count: 2
Fractal Features and Structural Morphological Optical Characteristics of Sol-Gel Derived Silica Nanoparticled Thin Films
(Polish Acad Sciences Inst Physics, 2018) Uysal, Bengü Özuğur; Pekcan, Önder
Nanostructured silica films using a simple and effective sol-gel spin coating technique were synthesized and the influence of ammonia/sol ratios on the particle size and thickness of this film was investigated. In addition fractal dimensions of the prepared films were determined using the scattering response technique. The samples were characterized by atomic force microscopy and UV-vis spectroscopy. Comparing optical method and image analysis of atomic force microscopy micrographs the fractal dimension of silica nanoparticled thin films was determined. The fractal dimensions of the films verified by atomic force microscopy analysis were found to be around 2.03 which is very close to the values (2.0358 2.0325 and 2.0335) obtained using optical method. As a result of these findings precise determination of the nanoparticled silica thin films fractal dimension using both optical and surface analysis methods was realized.
Citation Count: 1
Fuzzy-neural networks for medical diagnosis
(2010) Şenol, Canan; Yıldırım, Tülay
In this paper a novel fuzzy-neural network architecture is proposed and the algorithm is developed. Using this new architecture fuzzy-CSFNN fuzzy-MLP and fuzzy-RBF configurations were constituted and their performances have been compared on medical diagnosis problems. Here conic section function neural network (CSFNN) is also a hybrid neural network structure that unifies the propagation rules of multilayer perceptron (MLP) and radial basis function (RBF) neural networks at a unique network by its distinctive propagation rules. That means CSFNNs accommodate MLPs and RBFs in its own self-network structure. The proposed hybrid fuzzy-neural networks were implemented in a well-known benchmark medical problems with real clinical data for thyroid disorders breast cancer and diabetes disease diagnosis. Simulation results show that proposed hybrid structures outperform both MATLAB-ANFIS and non-hybrid structures. © 2010 Inderscience Enterprises Ltd.
Citation Count: 6
How Do Women Receive Inheritance? The Processes of Turkish Women's Inclusion and Exclusion from Property
(SOOKMYUNG WOMENS UNIV, 2013) Toktaş, Şule; O'Neil, Mary Lou
This article employs Turkey as a case study to explore the relationship between property ownership inheritance and women's empowerment. In Turkey as in much of the world men dominate ownership of property. This is despite the fact that women have had equal rights to own and inherit property since 1926. With the establishment of the Republic in 1923 came a series of reforms one of which replaced Islamic Sharia law with a secular civil law that was based on the Swiss Civil Code. The new law among other things guaranteed equal rights of property and inheritance regardless of gender. In an attempt to understand the tangled relationship between property and women's empowerment we conducted interviews regarding inheritance practices among ideologically secular wealthy women in Istanbul. For these women and their families the logic of wealth distribution is deeply informed by a commitment to equality between children with little regard for gender. Even in those cases where strict equality in terms of sameness was not employed the goal was for an overall balance and fairness between recipients. Despite the fact that inheritance law provides for equality most of the families employed interuivos transfer
Citation Count: 0
Joint data detection and channel estimation for uplink MC-CDMA systems over frequency selective channels
(Springer, 2007) Panayırcı, Erdal; Doğan, Hakan; Çırpan, Hakan Ali; Fleury, Bernard Henri
This paper is concerned with joint channel estimation and data detection for uplink multicarrier code-division multiple-access (MC-CDMA) systems ill the presence of frequency fading channel. The detection and estimation implemented at the receiver are based on a version of the expectation maximization (EM) algorithm which is very suitable for the the multicarrier signal formats. Application of the EM-based algorithm to the problem of iterative data detection and channel estimation leads to a receiver structure that also incorporates a partial interference cancelation. Computer simulations show that the proposed algorithm has excellent BER end estimation performance.
Citation Count: 0
Mountain Bike Venue Test Event Noise Assessment London 2012 Olympic And Paralympic Games
(Studıo D-Akustika Sro, 2016) Şaher, Konca
This article reports the results of the noise monitoring during the London 2012 Mountain Biking Test Event which was held at Hadleigh Farm. The noise monitoring was held during the Mountain Bike Test Event for two purposes: Firstly as part of the requirements of Environmental Management Plan for the Test Event to ensure that no noise disturbance was being caused and the noise levels were below the agreed criterion of 65 dB(A) at the noise sensitive receptors during the Test Event and secondly to check whether any additional mitigation measures need to be adopted for the main Olympic Event. The noise monitoring results indicate that the L-Aeq noise levels at the selected two noise sensitive receptors were below the 65 dB(A) criterion. The results confirmed the predictions that the crowd noise was not a noise nuisance during the Test Event and the results further showed that no noise nuisance at the noise sensitive receptors was caused by public adress system. The public address system to be used during the main event was very similar to the Test Event therefore it was possible to conclude that the noise nuisance from the event (public address system and spectator noise) could be assessed as being moderate to low risk during the main Games.
Citation Count: 4
PAAm-kappa carrageenan composites: drying and swelling with various kappa carrageenan contents
(Polish Acad Sciences Inst Physics, 2012) Akın-Evingür, Gülşen; Pekcan, Önder
The purpose of this study is to discuss the role of kappa-carrageenan (kappa-car) in the drying and swelling of polyacrylamide (PAAm)-kappa-car composite. The fluorescence intensity of pyranine increased and decreased as drying and swelling time were increased respectively for all samples. The desorption coefficient D-d decreased as kappa-car contents were increased for a given temperature during drying. However cooperative diffusion coefficient D-s increased as kappa-car contents were increased during swelling at a given temperature.
Citation Count: 0
POST-HEGEMONIC (DIS)ORDER AND REGIIONAL BALANCING STRATEGIES IN THE MIDDLE EAST
(Univ Complutense Madrid, 2019) Ifantis, Kostas
Following the so-called Arab Spring, the strategic situation in the Middle East has been one of disorder. A series of critical, complex and interrelated security failures have resulted in chaos and bloodshed unprecedented even for a region with Middle East's history and legacy. The demand for intervention has been high but the response has been very low. In such an unchartered and rapidly deteriorating regional security setting, this paper argues that the conspicuous absence of US hegemonic engagement has allowed for the return to overt regional balance of power strategies and proxy conflicts. Our hypothesis is that a regional balance of power and the resulting order (or disorder) heavily depends on the type of great power regional engagement. In such a context, the "hands off" or non-hegemonic approach that characterizes US strategy since the Arab Spring eruption has heavily contributed to a highly disorderly regional balance of power landscape. In the absence of US hegemonic involvement, revisionist threats emerge and local rivalries intensify.
Citation Count: 0
Rapidly Varying Sparse Channel Tracking with Hybrid Kalman-OMP Algorithm
(Springer, 2019) Şenol, Habib; Erküçük, Serhat; Erküçük, Serhat; Cirpan, Hakan Ali
It is expected from future communication standards that channel estimation algorithms should be able to operate over very fast varying frequency selective channel models. Therefore in this study autoregressive (AR) modeled fast varying channel has been considered and tracked with Kalman filter over one orthogonal frequency division multiplexing (OFDM) symbol. Channel sparsity is exploited which decreases the complexity requirements of the Kalman algorithm. Since Kalman filter is not directly applicable to sparse channels orthogonal matching pursuit (OMP) algorithm is modified for AR modeled sparse signal estimation. Also by using windows sparsity detection errors have been decreased. The simulation results showed that sparse fast varying channel can be tracked with the proposed hybrid Kalman-OMP algorithm and windowing method offers improved MSE results.
Citation Count: 0
Turkey past and future: The forgotten secular Turkish model
(2013) Ünver, Hamid Akın
[Abstract Not Available]
Citation Count: 3
Universality of elasticity on PAAM-NIPA copolymer gels
(EDP Sciences, 2015) Evingür, Gülşen Akin; Pekcan, Önder
Polyacrylamide (PAAm)-N-isopropylacrylamide (NIPA) copolymers were prepared via free radical crosslinking copolymerization with different molar of NIPA varying in the range between 0 and 2 M. The mechanical properties of swollen PAAm-NIPA copolymers were characterized by the compressive testing technique. It is understood that the compressive elastic modulus was found to increase by increasing NIPA contents keeping temperature constant at 30 degrees C. The critical exponent of elasticity y above the critical NIPA concentration is found to be as 0.74 which is consistent with the suggestions of percolation for superelastic percolation network (SEPN) and the critical theory for PAAm-NIPA copolymers.

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