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Infrared Multiple Photon Dissociation Spectroscopy of Protonated Histidine and 4-Phenylmidazole
No full textCitir, Murat/0000-0002-6666-4980; Oomens, Jos/0000-0002-2717-1278; Steill, Jeffrey/0000-0001-7339-2816;The gas-phase structures of protonated histidine (His) and the side-chain model, protonated 4-phenyl imidazole (PhIm), are examined by infrared multiple photon dissociation (IRMPD) action spectroscopy utilizing light generated by the free electron laser FELIX. To identify the structures present in the experimental studies, the measured IRMPD spectra are compared to spectra calculated at a B3LYP/6-311+G(d,p) level of theory. Relative energies of various conformers are provided by single point energy calculations carried out at the B3LYP, B3P86, and MP2(full) levels using the 6-311+G(2d,2p) basis set. On the basis of these experiments and calculations, the IRMPD action spectrum for H+(His) is characterized by a mixture of [N-pi,N-alpha] and [N-pi,CO] conformers, with the former dominating. These conformers have the protonated nitrogen atom of imidazole adjacent to the side-chain (N-pi) hydrogen bonding to the backbone amino nitrogen (N-alpha) and to the backbone carbonyl oxygen, respectively. Comparison of the present results to recent IRMPD studies of protonated histamine, the radical His(center dot+) cation, H+(HisArg), H-2(2+)(HisArg), and M+(His), where M+ = Li+, Na+, K+, Rb+, and Cs+, allows evaluation of the vibrational motions associated with the observed bands. (c) 2012 Elsevier B.V. All rights reserved.National Science Foundation [PIRE-0730072, CHE-1049580]; Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO); Direct For Mathematical & Physical Scien; Division Of Chemistry [1049580] Funding Source: National Science FoundationFinancial support was provided by the National Science Foundation, Grants PIRE-0730072 and CHE-1049580. This work is also part of the research program of FOM, which is financially supported by the Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO). The skillful assistance of the FELIX staff, in particular Lex van der Meer, Britta Redlich, Giel Berden, and Josipa Grzetic, is gratefully acknowledged. In addition, we thank the Center for High Performance Computing at the University of Utah for the generous allocation of computer time
Analysis of Coronary Angiography Related Psychophysiological Responses
No full textKara, Sadik/0000-0001-6063-6455Background: Coronary angiography is an important tool in diagnosis of cardiovascular diseases. However, it is the administration is relatively stressful and emotionally traumatic for the subjects. The aim of this study is to evaluate psychophysiological responses induced by the coronary angiography instead of subjective methods such as a questionnaire. We have also evaluated the influence of the tranquilizer on the psychophysiological responses. Methods: Electrocardiography (ECG), Blood Volume Pulse (BVP), and Galvanic Skin Response (GSR) of 34 patients who underwent coronary angiography operation were recorded. Recordings were done at three phases: "1 hour before," "during," and "1 hour after" the coronary angiography test. Total of 5 features obtained from the physiological signals were compared across these three phases. Sixteen of the patients were administered 5 mg of a tranquilizer (Diazepam) before the operation and remaining 18 were not. Results: Our results indicate that there is a strong correlation between features (LF/HF, Bk, DN1/DN2, skin conductance level and seg_mean) in terms of reflecting psychophysiological responses. However only DN1/DN2 feature has statistically significant differences between angiography phases (for diazepam: p = 0.0201, for non_diazepam p = 0.0224). We also note that there are statistically significant differences between the diazepam and non-diazepam groups for seg_mean features in "before", "during" and "after" phases (p = 0.0156, 0.0282, and 0.0443, respectively). Conclusions: The most intense sympathetic activity is observed in the "during" angiography phase for both of the groups. The obtained features can be used in some clinical studies where generation of the customized/individual diagnoses styles and quantitative evaluation of psychophysiological responses is necessary
Effect of Granulated Blast Furnace Slag and Fly Ash Addition on the Strength Properties of Lightweight Mortars Containing Waste PET Aggregates
No full textAkcaozoglu, Semiha/0000-0003-1033-5819;In this work, the effect of Granulated Blast Furnace Slag (GBFS) and fly ash (FA) addition on the strength properties of lightweight mortars containing waste Poly-ethylene Terephthalate (PET) bottle aggregates was investigated. Investigation was carried out on three groups of mortar specimens. One made with only Normal Portland cement (NPC) as binder, second made with NPC and GBFS together and, third made with NPC and FA together. The industrial wastes mentioned above were used as the replacement of cement on mass basis at the replacement ratio of 50%. The size of shredded PET granules used as aggregate for the preparation of mortar mixtures were between 0 and 4 mm. The waste lightweight PET aggregate (WPLA)-binder ratio (WPLA/b) was 0.60; the water-binder (w/b) ratios were determined as 0.45 and 0.50. The dry unit weight, compressive and flexural-tensile strengths, carbonation depths and drying shrinkage values were measured and presented. The results have shown that modifying GBFS had positive effects on the compressive strength and drying shrinkage values (after 90 days) of the WPLA mortars. However, FA substitution decreased compressive and flexural-tensile strengths and increased carbonation depths. Nevertheless a visible reduction occurred on the drying shrinkage values of FA modifying specimens more than cement specimens and GBFS modified specimens. The test results indicated that, GBFS has a potential of using as the replacement of cement on the WPLA mortars by taking into consideration the characteristics. But using FA as a binder at the replacement ratio of 50% did not improve the overall strength properties. Although it was thought that, using FA as binder at the replacement ratio of 50% for the aim of production WPLA concrete which has a specific strength, would provide advantages of economical and ecological aspects. (C) 2011 Elsevier Ltd. All rights reserved.Cukurova University [MMF2006D23]The authors would like thank Cukurova University Scientific Research Projects Directorate that supported the present work (Project number: MMF2006D23)
The Effects of Different Types of Fly Ash on the Compressive Strength Properties of Briquettes
No full textSayin, Baris/0000-0002-2437-1709; Atis, Cengiz Duran/0000-0003-3459-329X;The aim of this study is to evaluate the effect of the different types of fly ash on the compressive strength properties of sintered briquettes. Thermal gravimetric (TG) analysis was carried out. The chemical composition and physical properties of the materials used were determined. Particle size distribution and microstructure elemental analyses of the materials used were carried out by a particle size analyzer (Mastersizer) and a scanning electron microscope (SEM-EDS). Following the characterization of the materials, briquettes were prepared by sintering at different temperatures. Compressive strength test results of the briquette samples indicated that briquettes with a compressive strength value of 47.45 N/mm(2) can be produced. The results obtained exceed the Turkish standard (TS EN 771-1) requirements (9.8-23.54 N/mm(2)). SEM-EDS results showed that briquette samples made with Tuncbilek (T) fly ash had a higher percentage of the glassy phase than the other briquette samples. Due to this microstructure, it results in higher compressive strength value.Scientific Research Projects Coordination Unit of Istanbul University [UDP-4547/13112009]The authors would like to thank Istanbul Asphalt Factories Head of Production Zafer Sola for helping. This work was supported by the Scientific Research Projects Coordination Unit of Istanbul University, Project number UDP-4547/13112009
Design and Implementation of a Voice-Controlled Prosthetic Hand
No full textAksebzeci, Bekir Hakan/0000-0001-7476-8141Current hand prostheses are mostly driven by electromyography (EMG) signal, and existing experiments have proved that multichannel EMG signal controls are not suitable due to early fatigue problems and high effort, requirements to perform even simple activities. Therefore, in this study we present a new voice-controlled active hand prosthesis to perform several basic tasks. We first designed a novel multifingered prosthetic hand with the ability of picking up and releasing objects. The prosthetic hand employs 3 DC motors and gears to transfer motion to the linked parts of the fingers. We used flexible thin-film, resistive force sensors at the fingertips of the prosthetic hand to adjust the grip force at the fingers. The second part of the study involves the use of speech recognition to control the prosthetic hand. The control circuit that we designed consisted of an HM2007 speech recognition IC and a PIC microcontroller to drive the DC motors moving the fingers. We implemented both the prosthetic hand and its speech recognition-based control electronics. As of now, we have programmed the control hardware to recognize simple pick up and release operations and have successfully tested them. In a future study, we will include more voice commands for the operation of the hand, such as a realistic handshake, and improve the cosmetics of the hand in order to make it look more natural
YENİ YÜZYILDA TÜRK DIŞ POLİTİKASININ UFUKLARI
No full textTürkiye, uluslararası sistem içinde herhangi bir ülke değildir. Tek bir coğrafi bölgeyle tanımlanamayan, kıtaların ve havzaların kesişme noktasını oluşturan jeostratejik konumumuz, Osmanlı mirasımız, Doğu'yla Batı'yı meczeden sosyo-kültürel yapımız ve transatlantik ittifak içindeki özel konumumuz nedeniyle, ulusal çıkarlarımız çok farklı coğrafyalara ve alanlara yayılmış durumdadır. Türkiye'nin bölgesine ve uluslararası sisteme dar kalıplar tanımlanmış güvenlik çıkarları açısından bakan değil, çıkarlarını daha geniş bir çerçevede, uluslararası ve bölgesel işbirliği çerçevesinde tanımlayan bir ülke olarak 21. yüzyıla damgasını vurmasını hedefliyoruz. Statükocu, tepkisel, ve agresif değil, uzlaşma kültürüne açık ve çevresinde olumlu değişiklikleri teşvik eden bir politikayla çıkarlarımızı daha iyi savunabileceğimizi düşünüyoruz. Artık ''çevremiz hasımlarla çevrili'' varsayımına dayanan çatışma psikolojisinden çıkarak, ''çevremizle işbirliği ve diyalog ortamının kurucu aktörü'' rolünü benimsemek zorundayız. Büyük ülke ideali, ancak böyle bir özgüvenle gerçekleştirilebilir.We must act with a refreshed visıon- a visian in which good governance, transparency and accountability will reign, the fundamental rights and freedoms as well as gender equality are upheld, and there would be no place for blunting rhetoric and slogans. In short, we should first put our house ın order. Rational thinking should be our dividing force, as we our strength from our spiritual values. Creating a synergy from these values inherent in our being will be our test in as well as out contribution to our modern age