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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 Effects of childhood trauma and clinical features on determining quality of life in patients with bipolar I disorder(Elsevier Science BV, 2014-06-20) Erten, Evrim; Funda Uney, Aslı; Saatçioğlu, İbrahim Ömer; Özdemir, Armağan; Fıstıkçı, Nurhan; Çakmak, DuranBackground: We explored how childhood trauma (CHT) affects the clinical expression of disorder and quality of life in patients with bipolar I (BP I) disorder.Methods: Euthymic patients (n=116) who subsequently received a diagnosis of BP-I disorder were consecutively included and were interviewed using the following sociodemographic and clinical data forms; Young Mania Rating Scale (YMRS), Hamilton Depression Rating Scale (HDRS), Childhood Abuse and Neglect Questionnaire (CANQ) and the 36 item Medical Outcome Study Short Form Health Survey (SF 36) The quality of life of BP-I patients with and without a history of CHT were examined.Results: The percentage of trauma was 61.2%. Patients who had CHT had higher frequencies of depressive episodes (t = -2.38, p=0.019), total episodes (t = -2.25, p=0.026), attempted suicide more often (chi(2)=18.12, p=0.003) and had lower scores on the pain subscale of Lhe SF 36 (z=-2.817, p=0.005). In patients with mixed or rapid-cycling episodes, SF-36 subscale scores except general health and pain were Found to be lower.Limitations: Our sample may fail to reflect the general BD population; the patients were included consecutively and consisted of a majority of female patients.Conclusions: CHT plays an important role in the clinical expression of BP-I disorder and having mixed/rapid-cycling episodes negatively affects both physical and mental components, as measured by the SF-36. While both males and females reported experiencing sexual abuse, female BP-I patients complained about pain more often. It is suggested that treatment of BP-1 patients with a history of CHT should differ from that provided for patients with no CHT history.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 Spectral renormalization group for the Gaussian model and 𝜓4 theory on nonspatial networks(American Physical Society, 2015-08-06) Tuncer, Aslı; Erzan, AyşeWe implement the spectral renormalization group on different deterministic nonspatial networks without translational invariance. We calculate the thermodynamic critical exponents for the Gaussian model on the Cayley tree and the diamond lattice and find that they are functions of the spectral dimension, (d) over tilde. The results are shown to be consistent with those from exact summation and finite-size scaling approaches. At (d) over tilde = 2, the lower critical dimension for the Ising universality class, the Gaussian fixed point is stable with respect to a psi(4) perturbation up to second order. However, on generalized diamond lattices, non-Gaussian fixed points arise for 2 < <(d)over tilde> < 4.Yayın Photon transmission study on conformational ordering of iota-carrageenan in CaCl2 solution(Taylor & Francis Inc, 2005-06) Kara, Selim; Pekcan, Mehmet ÖnderCoil-to-double helix (c-h) and double helix-to-dimer (h-d) phase transitions of iota-carrageenan in CaCl2 solution upon cooling were studied using photon transmission technique. Photon transmission intensity, I-iota r was monitored against temperature to determine the (c-h) and (h-d) transition temperatures (T-ch and T-hd) and activation energies (Delta E-ch and Delta E-hd). An extra dimer-to-dimer (d-d) transition was also observed during cooling at low temperature region. However, upon heating dimers disappear to double helices by making dimer-to-double helix (d-h) transition. Further heating resulted double helix-to-coil (h-c) transition at high temperature region. T-dh and T-ch temperatures and Delta E-dh and Delta E-hc activation energies were also determined. It was observed that T-hc and T-ch temperatures and Delta E-dh and Delta E-hd activation energies do not effected by carrageenan content. However, T-hd, T-dh and T-dd temperatures and Delta E-ch and Delta E-hc activation energies were found to be strongly correlated to the carrageenan content in the system.Yayın I (dis)like the way you (dis)like them: The role of extended contact on social distance and attitudes towards the ingroup(Wiley, 2020-04) Bağcı Hemşinlioğlu, Sabahat Çiğdem; Stathi, Sofia; Vezzali, Loris; Türnüklü, Abbas; Piyale, Zeynep EcemWhile extended intergroup contact has been commonly studied in the context of prejudice reduction, less is known about its implications for processes related to the ingroup. Through three correlational and one experimental studies (total N = 897) conducted in two different intergroup contexts (Turkey and United Kingdom), we investigated whether extended intergroup contact relates to social distance and attitudes towards ingroup members as a function of outgroup attitudes. We also investigated ingroup identification and perceived ingroup morality as potential mediators in these associations. Correlational studies demonstrated that especially when outgroup attitudes were more negative, participants' positive (but not negative) extended contact was related to a more negative evaluation of the ingroup; whereas when outgroup attitudes were more positive, extended contact was associated with positive attitudes towards the ingroup. We found experimental evidence for the suggested relationships in relation to ingroup social distance. Findings are discussed in the light of vicarious dissonance theory and deprovincialization hypothesis.Yayın People respond with different moral emotions to violations in different relational models: a cross-cultural comparison(American Psychological Association, 2021-06) Sunar, Diane; Cesur, Sevim; Piyale, Zeynep Ecem; Tepe, Beyza; Biten, Ali Furkan; Hill, Charles T.; Koç, YasinConsonant with a functional view of moral emotions, we argue that morality is best analyzed within relationships rather than in individuals, and use Fiske's (1992) theory of relational models (RMs: communal sharing [CS], authority ranking [AR]. equality matching [EM], and market pricing [MP]) to predict that violations in different RMs will arouse different intensities of other-blaming emotions (anger, contempt and disgust) in both observers and victims, together with different intensities of self-blaming emotions (shame and guilt) in perpetrators, and to predict that these patterns of emotion will show similarity across both individuals and cultures. Three studies, using vignettes portraying moral violations in all RMs in different experimental designs. supported these expectations. while also producing some unexpected results. The intensity of shame and guilt varied markedly across RMs, but with little difference between the two emotions. The intensity of all 3 other-blaming emotions also varied across RMs. Anger was the most intense emotional response to violation in all RMs, whereas disgust and contempt were stronger in CS than in other RMs. Disgust and shame were linked more strongly in CS than in other RMs, and anger and guilt were more strongly linked than other emotion pairs in EM. Moral emotions in RMs involving hierarchy (AR and MP) differed widely depending on the perpetrator's dominant or subordinate status. Both Turkish (TR) and English-speaking (EN) samples showed similar patterns of all moral emotions across RMs. Understanding the functions of moral emotions in relationships using relational models can help to clarify multiple aspects of moral psychology.Yayın Spherical coding algorithm for wavelet image compression(IEEE-Inst Electrical Electronics Engineers Inc, 2009-05) Ateş, Hasan Fehmi; Orchard, Michael T.In recent literature, there exist many high-performance wavelet coders that use different spatially adaptive coding techniques in order to exploit the spatial energy compaction property of the wavelet transform. Two crucial issues in adaptive methods are the level of flexibility and the coding efficiency achieved while modeling different image regions and allocating bitrate within the wavelet subbands. In this paper, we introduce the "spherical coder," which provides a new adaptive framework for handling these issues in a simple and effective manner. The coder uses local energy as a direct measure to differentiate between parts of the wavelet subband and to decide how to allocate the available bitrate. As local energy becomes available at finer resolutions, i.e., in smaller size windows, the coder automatically updates its decisions about how to spend the bitrate. We use a hierarchical set of variables to specify and code the local energy up to the highest resolution, i.e., the energy of individual wavelet coefficients. The overall scheme is nonredundant, meaning that the subband information is conveyed using this equivalent set of variables without the need for any side parameters. Despite its simplicity, the algorithm produces PSNR results that are competitive with the state-of-art coders in literature.Yayın An integrated circuit with transmit beamforming flip-chip bonded to a 2-D CMUT array for 3-D ultrasound imaging(IEEE-INST Electrical Electronics Engineers Inc, 2009-10) Wygant, Ira O.; Jamal, Nafis S.; Lee, Hyunjoo J.; Nikoozadeh, Amin; Oralkan, Ömer; Karaman, Mustafa; Khuri-Yakub, Butrus ThomasState-of-the-art 3-D medical ultrasound imaging requires transmitting and receiving ultrasound using a 2-D array of ultrasound transducers with hundreds or thousands of elements. A tight combination of the transducer array with integrated circuitry eliminates bulky cables connecting the elements of the transducer array to a separate system of electronics. Furthermore, preamplifiers located close to the array can lead to improved receive sensitivity. A combined IC and transducer array can lead to a portable, high-performance, and inexpensive 3-D ultrasound imaging system. This paper presents an IC flip-chip bonded to a 16 x 16-element capacitive micromachined ultrasonic transducer (CMUT) array for 3-D ultrasound imaging. The IC includes a transmit beamformer that generates 25-V unipolar pulses with programmable focusing delays to 224 of the 256 transducer elements. One-shot circuits allow adjustment of the pulse widths for different ultrasound transducer center frequencies. For receiving reflected ultrasound signals, the IC uses the 32-elements along the array diagonals. The IC provides each receiving element with a low-noise 25-MHz-bandwidth transimpedance amplifier. Using a field-programmable gate array (FPGA) clocked at 100 MHz to operate the IC, the IC generated property timed transmit pulses with 5-ns accuracy. With the IC flip-chip bonded to a CMUT array, we show that the IC can produce steered and focused ultrasound beams. We present 2-D and 3-D images of a wire phantom and 2-D orthogonal cross-sectional images (B-scans) of a latex heart phantom.Yayın Imagined contact facilitates acculturation, sometimes: contradicting evidence from two sociocultural contexts(Educational Publishing Foundation-American Psychological Assoc, 2019-10) Bağcı Hemşinlioğlu, Sabahat Çiğdem; Piyale, Zeynep Ecem; Stathi, SofiaObjective: Imagined intergroup contact has been shown to be an effective tool to improve intergroup relationships in various settings, yet the application of the strategy among minority group members and across cultures has been scarce. The current research aimed to test imagined contact effects on minority group members' acculturation strategies (contact participation and culture maintenance), perceived discrimination, feelings of belongingness, and social acceptance across three studies conducted in the United Kingdom (Study 1) and Turkey (Studies 2 and 3). Method: The sample consisted of Eastern Europeans in Study 1 (N = 63) and Kurds in Study 2 and 3 (N = 66 and 210, respectively). Participants were randomly assigned to 1 of 2 conditions (control vs. imagined contact) and completed measures of acculturation, perceived discrimination, general belongingness, and social acceptance. Results: Findings showed that while imagined contact significantly reduced perceived discrimination and culture maintenance, and increased contact participation and social acceptance among Eastern Europeans (Study 1), it reduced social acceptance and contact participation among Kurds recruited from a conflict-ridden homogeneous setting (Study 2). With a larger and more heterogeneous sample of Kurds (Study 3), these effects occurred only among those with higher ingroup identification. Moreover, in all studies social acceptance mediated the effects of imagined contact on contact participation and perceived discrimination. Discussion. Findings offer important insights about the use of the imagined contact strategy among minority group members and imply the need to take into account the context-dependent nature of contact strategies.
