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Yayın Vapor-induced film formation from low-T-g particles for different solvent compositions(Elsevier Inc, 2006-05-15) Arda, Ertan; Kara, Selim; Saraç, Ayfer; Pekcan, Mehmet ÖnderThe photon transmission method was used to study latex film formation from poly(vinyl acetate) (PVAc) particles induced by two different solvents. Films with the same latex content were prepared from PVAc particles and exposed to vapor of ethanol-water and acetone-water mixtures in various compositions. Transmitted photon intensities, I-tr, from these films increased with increasing vapor exposure time. The increase in I-tr is attributed to the increase in crossing density at the polymer-polymer junction. The Prager-Tirrell model was employed to obtain the back-and-forth frequency, v, of the reptating polymer chain during film formation induced by solvent vapor. It was observed that the produced v values increase as the solvent content is increased for both solvents. Abilities of both solvents to form films were interpreted with the solubility parameters of the solvents and the PVAc.Yayın Volumetric ultrasound imaging using 2-D CMUT arrays(IEEE-Inst Electrical Electronics Engineers Inc, 2003-11) Oralkan, Ömer; Ergün, Arif Sanlı; Cheng, Ching-Hsiang; Johnson, Jeremy A.; Karaman, Mustafa; H. Lee, Thomas; Khuri-Yakub, Butrus ThomasRecently, capacitive micromachined ultrasonic transducers (CMUTs) have emerged as a candidate to overcome the difficulties in the realization of 2-D arrays for real-time 3-D imaging. In this paper, we present the first volumetric images obtained using a 2-D CMUT array. We have fabricated a 128 x 128-element 2-D CMUT array with through-wafer via interconnects and a 420-mum element pitch. As an experimental prototype, a 32 x 64-element portion of the 128 X 128-element array was diced and flip-chip bonded onto a glass fanout chip. This chip provides individual leads from a central 16 X 16-element portion of the array to surrounding bondpads. An 8 x 16-element poition of the array was used in the experiments along with a 128-channel data acquisition system. For imaging phantoms, we used a 2.37-mm diameter steel sphere located 10 mm from the array center and two 12-mm-thick Plexiglas plates located 20 mm and 60 mm from the array. A 4 X 4 group of elements in the middle of the 8 X 16-element array was used in transmit, and the remaining elements were used to receive the echo signals. The echo signal obtained from the spherical target presented a frequency spectrum centered at 4.37 MHz with a 100% fractional bandwidth, whereas the frequency spectrum for the echo signal from the parallel plate phantom was centered at 3.44 MHz with a 91% fractional bandwidth. The images were reconstructed by using RF beamforming and synthetic phased array approaches and visualized by surface rendering and multiplanar slicing techniques. The image of the spherical target has been used to approximate the point spread function of the system and is compared with theoretical expectations. This study experimentally demonstrates that 2-D CMUT arrays can be fabricated with high yield using silicon IC-fabrication processes, individual electrical connections can be provided using through-wafer vias, and flip-chip bonding can be used to integrate these dense 2-D arrays with electronic circuits for practical 3-D imaging applications.Yayın Normative data and factorial structure of the Turkish version of the junior temperament and character inventory-revised(Taylor & Francis, 2017) Köse, Samet; Çam Çelikel, Feryal; Akın, Ercan; Kaya, Cahit; Elbozan Cumurcu, Birgül; Etikan, İlker; Cloninger, Claude RobertObjective: Junior Temperament and Character Inventory (J-TCI) was developed by Luby, Svrakic, McCallum, Przybeck, and Cloninger based on Cloninger's biopsychosocial model to assess temperament and character dimensions in children and adolescents. Methods: The Turkish version of J-TCI-Revised (J-TCI-R) was administered to 1129 elementary and middle-school (male/female, 546/583) students. Internal consistency reliabilities were measured by Cronbach's alpha; test-retest was assessed across one month. Results: Cronbach's alphas for the subscales of J-TCI-R ranged from 0.60 to 0.75 for temperament and character subscales, which were comparable to US and other populations. The correlations between baseline and one month after administration of J-TCI-R were highly and statistically significant (r = 0.578-0.674 for scales and 0.366-0.582 for subscales) (n = 795). Factor analysis results using Eigenvalue greater than one rule indicated three out of four factors for temperament scales and one out of two factors for character subscales which were similar to findings from the other countries. When all of the subscales were subjected to factor analysis, four out of six factors were retained. To our knowledge, this is the first study analysing psychometric properties and factorial construct of the J-TCI-R. Conclusions: The internal reliability coefficients and test-retest indicated a good stability of scores over time and the factorial structure was consistent with Cloninger's model of personality. The reliability and validity of the Turkish version of the TCI is therefore supported.Yayın P-T phase diagram for NH4F(Editions Scientifiques Medicales Elsevier, 2002-04) Salihoğlu, Selami; Yurtseven, Hasan Hamit; Enginer, YücelIn this study we obtain a P-T phase diagram of NH4F using the mean-field theory. We fit our calculated phase line equations to the experimental P-T phase diagram. By choosing appropriately the coefficients in the free-energy expansions. our calculated phase diagram agrees well with the experimentally observed phase diagram of NH4F.Yayın Evolutionary route to diploidy and sex(National Academy of Sciences, 2001-11-20) Tüzel, Erkan; Sevim, Volkan; Erzan, AyşeBy using a bit-string model of evolution, we find a successful route to diploidy and sex in simple organisms. Allowing the sexually reproducing diploid individuals to also perform mitosis, as they do in a haploid-diploid cycle, leads to the complete takeover of the population by sexual diploids. This mechanism is so robust that even the accidental conversion and pairing of only two diploids give rise to a sexual population.Yayın Forward-viewing CMUT arrays for medical Imaging(IEEE-INST Electrical Electronics Engineers Inc, 2004-07) Demirci, Utkan; Ergün, Arif Sanlı; Oralkan, Ömer; Karaman, Mustafa; Khuri-Yakub, Butrus ThomasThis paper reports the design and testing of forward-viewing annular arrays fabricated using capacitive micromachined ultrasonic transducer (CMUT) technology. Recent research studies have shown that CMUTs have broad frequency bandwidth and high-transduction efficiency. One- and two-dimensional CMUT arrays of various sizes already have been fabricated, and their viability for medical imaging applications has been demonstrated. We fabricated 64-element, forward-viewing annular arrays using the standard CMUT fabrication process and carried out experiments to measure the operating frequency, bandwidth, and transmit/receive efficiency of the array elements. The annular array elements, designed for imaging applications in the 20 MHz range, had a resonance frequency of 13.5 MHz in air. The immersion pulse-echo data collected from a plane reflector showed that the devices operate in the 5-26 MHz range with a fractional bandwidth of 135%. The output pressure at the surface of the transducer was measured to be 24 kPa/V. These values translate into a dynamic range of 131.5 dB for I-V excitation in 1-Hz bandwidth with a commercial low noise receiving circuitry. The designed, forward-viewing annular CMUT array is suitable for mounting on the front surface of a cylindrical catheter probe and can provide Doppler information for measurement of blood flow and guiding information for navigation through blood vessels in intravascular ultrasound imaging.Yayın Anti-tobacco control industry strategies in Turkey(BioMed Central Ltd, 2018-02-26) Keklik, Seda; Gültekin Karakas, DeryaBackground: Transnational tobacco companies (TTCs) penetrated the Turkish cigarette market due to trade and investment liberalization in the post-1980 period and eventually secured full control. Despite tobacco control policies put in place in reaction to accelerating consumption, TTCs reinforced their market power through a variety of strategies. This paper explores industry strategies that counteract tobacco control policies in Turkey. Methods: The study employs both qualitative and quantitative analyses to explore industry strategies in Turkey. Besides the content analyses of industry and market reports, descriptive analyses were conducted for the sub-periods of 1999-2015. The analyses focus on the market strategies of product innovation, advertisement-promotion, cost management and pricing. Results: Rising sales of low tar, ultra-low tar, slim, super-slim and flavoured cigarettes indicate that product innovation served to sustain consumption. Besides, the tobacco industry, using its strong distribution channels, the Internet, and CSR projects, were found to have promoted smoking indirectly. The industry also rationalized manufacturing facilities and reduced the cost of tobacco, making Turkey a cigarette-manufacturing base. Tobacco manufacturers, moreover, offered cigarettes in different price segments and adjusted net prices both up and down according to price categories and market conditions. In response to the successful effect of shifts in price margins, the market share of mid-priced cigarettes expanded while those within the economy category maintained the highest market share. As a result of pricing strategies, net sales revenues increased. Aside from official cigarette sales, the upward trends in the registered and unregistered sales of cigarette substitutes indicate that the demand-side tobacco control efforts remain inadequate. Conclusions: The Turkish case reveals that the resilience of the tobacco industry vis-a-vis mainstream tobacco control efforts necessitates a new policy perspective. Rising market concentration by TTCs and the global nature of industry strategies require that the highly profitable manufacturing and trade of tobacco products should be discouraged on a basis of international collaboration. To reduce and eventually eradicate tobacco consumption, supply-side tobacco control measures are needed along with demand-side policies.Yayın Olanzapin kullanımına bağlı çekilme diskinezisi ve süpersensitivite psikozu(Turkish Neuropsychiatric Society, 2016-06) Karaş, Hakan; Güdük, Mehmet; Saatçioğlu, İbrahim ÖmerTardive dyskinesia (TD) usually appears after years of antipsychotic drug use and appears to be related to the total lifetime medication dose. In withdrawal-emergent dyskinesia (WE-D), which is considered to be a subtype of TD, dyskinetic symptoms often appear shortly after a rapid reduction in antipsychotic drug dose or sudden discontinuation of the drug. Supersensitivity psychosis, which is frequently observed along with TD and is considered to have a similar etiology as TD, is a psychotic relapse phenomenon that occurs after the withdrawal of an antipsychotic drug or a rapid reduction in the drug dosage. In general, atypical antipsychotics tend to be associated with less propensity to cause TD when compared with typical antipsychotics. Furthermore, olanzapine and clozapine may have a therapeutic potential in improving or totally curing TD. In this study, a case of WE-D because of discontinuing olanzapine use and supersensitivity psychosis is discussed.Yayın Reliability, validity, and factorial structure of the Turkish version of the Empathy Quotient (Turkish EQ)(Taylor & Francis Ltd, 2018-07-03) Köse, Samet; Çam Çelikel, Feryal; Kulacaoğlu, Filiz; Akın, Ercan; Yalçın, Mehmet; Ceylan, VedatOBJECTIVES: Empathy is an essential ability that allows us to tune into how others are feeling or thinking. Empathy makes it possible to resonate with others' positive and negative feelings alike so that we can thus feel happy when we vicariously share the joy of others and we can share the experience of suffering when we empathize with someone in pain. Empathy training not only promotes prosocial behaviour, but also augments positive affect and resilience, which in turn fosters better coping with stressful situations. The Empathy Quotient (EQ) is a self-report questionnaire that was developed to measure the cognitive, affective, and behavioural aspects of empathy. Here, we aimed to examine the validity, reliability, and factor structure of the EQ in a Turkish sample. METHODS: Participants were 436 mostly college students and civil servants (195 female, 241 male). Sociodemographic information, the Turkish version of the EQ, Marlowe-Crowne Social Desirability Scale (MC-SDS) 33-item full version and MC-SDS 13-item shorter versions were administered. All statistical analyses were performed by using SPSS version 23 for Windows. RESULT: EQ scores were significantly higher in female participants ((X) over bar (Female)=46.45, SDFemale=0.62) compared to the male participants ((X) over bar (Male)=43.68, SD (Male)=0.56). The Cronbach's alpha coefficient for the scale was 0.76, Guttman's split-half reliability coefficient was 0.61, and test-retest reliability coefficient was 0.95. A positive and statistically significant correlation was found between the Turkish EQ and MC-SDS Full version (r=0.299, p<.01) and short form of MC-SDS (r=0.273, p<.01). A three-factor solution that accounted for 25.28% of the variance observed. CONCLUSIONS: The Turkish version of the EQ has satisfactory validity, good internal and test-retest reliability with a robust factorial structure to use in a clinical population in Turkey. Moreover, as predicted, women scores were statistically significantly higher on the EQ than men. This result was consistent with a series of earlier studies reporting gender differences (female superiority) on questionnaires that measure empathy. A better knowledge of empathy will have important implications for the examination and understanding of certain neurological and psychiatric disorders, including autism, narcissistic and antisocial personality disorders, and may also provide important clues about the relevant brain circuitry underlying empathy.Yayın Annular-ring CMUT arrays for forward-looking IVUS: Transducer characterization and imaging(IEEE, 2006-02) Değertekin, Fahrettin Levent; Güldiken, Rasim Oytun; Karaman, MustafaIn this study, a 64-element, 1.15-mm diameter annular-ring capacitive micromachined ultrasonic transducer (CMUT) array was characterized and used for forward-looking intravascular ultrasound (IVUS) imaging tests. The array was manufactured using low-temperature processes suitable for CMOS electronics integration oil a single chip. The measured radiation pattern of a 43 X 140- mu m(2) array element depicts a 40 degrees view angle for forward-looking imaging around a 15-MHz center frequency in agreement with theoretical models. Pulse-echo measurements show a -10-dB fractional bandwidth of 104% around 17 MHz for wire targets 2.5 mm away from the array in vegetable oil. For imaging and SNR measurements, RF A-scan data sets from various targets were collected using all interconnect scheme forming a 32-element array configuration. An experimental point spread function was obtained and compared with simulated and theoretical array responses, showing good agreement. Therefore, this study demonstrates that annular-ring CMUT arrays fabricated with CMOS-compatible processes are capable of forward-looking IVUS imaging, and the developed modeling tools can be used to design improved IVUS imaging arrays.
