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Yayın A stochastic risk-averse framework for blood donation appointment scheduling under uncertain donor arrivals(Springer, 2020-12) Yalçındağ, Semih; Baş Güre, Seda; Carello, Giuliana; Lanzarone, EttoreBlood is a key resource in all health care systems, usually drawn from voluntary donors. We focus on the operations management in blood collection centers, which is a key step to guarantee an adequate blood supply and a good quality of service to donors, by addressing the so-called Blood Donation Appointment Scheduling problem. Its goal is to employ appointment scheduling to balance the production of blood units between days, in order to provide a reasonably constant supply to transfusion centers and hospitals, and reduce non-alignments between physicians' working times and donor arrivals at the collection center. We consider a two-phase solution framework taken from the literature, in which a deterministic linear programming model preallocates time slots to different blood types and a prioritization policy assigns the preallocated slots to the donors when they make a reservation. However, the problem is stochastic in nature and requires consideration of the uncertain arrivals of non-booked donors. In this work, to include the uncertain arrivals, we propose three stochastic counterparts of the preallocation model based on a risk-neutral objective and two risk-averse objectives, respectively, where the Conditional Value-at-Risk is considered as the risk measure in the last two methods. The resulting stochastic frameworks have been tested considering the historical data of one of the largest Italian collection centers, the Milan Department of the "Associazione Volontari Italiani Sangue" (AVIS). Results show the effectiveness of the stochastic models, especially the mean-risk one, and the need to include the uncertainty of arrivals in order to better balance the production of blood units.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.Yayın Group efficacy as a moderator on the associations between perceived discrimination, acculturation orientations, and psychological well-being(Wiley, 2020-01-01) Bağcı Hemşinlioğlu, Sabahat Çiğdem; Canpolat, EsraWe investigated whether associations between perceived discrimination (PD), acculturation orientations (desire for culture maintenance and desire for contact), and well-being (psychological well-being and life satisfaction) were moderated by group efficacy beliefs-the extent to which group members believe in their ability to achieve social change collectively. We recruited 163 Syrian refugees (M-age = 36.43, SD = 12.68; 88 females and 75 males) from a south-eastern city in Turkey. PD was negatively associated with desire for culture maintenance and positively associated with desire for contact, indicating an assimilation trend as a response to PD. Both acculturation orientations in turn predicted well-being positively. However, the ones with higher group efficacy did not experience the detrimental effects of PD on well-being and indicated a stronger desire for contacting mainstream society. Further conditional indirect effects demonstrated that only among the ones with lower group efficacy, PD was related to lower psychological well-being through reduced culture maintenance. Findings indicate the critical role of group efficacy beliefs in the understanding of disadvantaged group members' reactions to PD.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 A clinical case of treatment-resistant schizophrenia: 60 hospitalizations and 342 ECT sessions in 36 years; lack of social support or undertreatment?(İstanbul Üniversitesi, 2015-06) Cesur, Ender; Fıstıkçı, Nurhan; Dönmezler, Fadime Gizem; Saatçioğlu, İbrahim ÖmerIt is reported that between 20% and 25% of patients have schizophrenia that is resistant to treatment. The treatment resistance in schizophrenia is defined by many authorities. One of the generally accepted definitions is inadequate response despite treatment with different atypical antipsychotics, two or three times at least four-six weeks; the other acceptable one is although the use of two different typical or atypical antipsychotics in monotherapy during four-six weeks, inadequate treatment response is obtained. Duratian of hospitalization in treatment resistant cases is longer. In addition, when considering all the expenses and loss of functions, the cost of resistant cases to society is higher. 60 years old, women patient. She was hospitalized from emergency department where she came with his son, because of denial of treatment and homicidal intent. It is learned that age of onset was 24, disease began in a postpartum period, she was diagnosed with schizophrenia and she had 60 hospitalizations. Although clozapine, haloperidol, amisulpiride, risperidone, olanzapine, aripiprazole, quetiapine, chlorpromazine, sulpiride, zuclopenthixol, fluphenazine, lithium and valproate were used adequate doses and time; a total of 342 ECT sessions were administered; response or partial response was achieved, she had not achieved long-term functioning and well-being. In the most recent admission, she had significant improvement with clozapine 275 mg/day and valproat 1000 mg/day. Despite all treatment efforts, schizophrenic patient with excessive admissions and frequent recurrences is discussed.Yayın Imagined contact in high conflict settings: The role of ethnic group identification and the perspective of minority group members(Wiley, 2018-01) Bağcı Hemşinlioğlu, Sabahat Çiğdem; Piyale, Zeynep Ecem; Ebcim, EfsaneRecent contact literature has shown that imagining a positive intergroup encounter improves intergroup attitudes and behaviors, yet less is known about the effects of imagined contact in high conflict settings. We conducted three studies to understand the potential effects of imagined intergroup contact among ethnic Turks ( majority status) and ethnic Kurds ( minority status) in the Turkish-Kurdish interethnic conflict setting. Study 1 (N = 47, Turkish) tested standard imagined contact effects ( neutral vs. standard imagined contact condition) among majority Turks and showed that imagined contact was effective on outgroup attitudes, perceived threat, intergroup anxiety, and support for multiculturalism only among participants with higher ethnic identification. Study 2 (N = 107, Turkish) examined how ethnic identification of the contact partner would influence the effectiveness of the standard imagined contact scenario ( neutral vs. standard vs. ethnic identification condition) and demonstrated that imagined contact effects were more negative when the contact partner identified with his/her ethnic group during imagined contact. Study 3 (N = 55, Kurdish) investigated imagined contact effects ( neutral vs. standard imagined contact condition) among an ethnic minority group and showed that imagined contact did not improve minority group members' outgroup attitudes, but did decrease intergroup anxiety and perceived discrimination (marginally significantly) and increased perceived positive attitudes from the majority group. Practical implications of the use of imagined intergroup contact strategy in conflict-ridden settings were discussed.Yayın The use of Facebook by Turkish mothers: its reasons and outcomes(Springer, 2020-03-01) Ögel Balaban, Hale; Altan, ŞebnemObjectives: Parents use social network sites for reasons related to bridging and bonding social capital, and entertainment. The aim of the present study was to examine whether the use of Facebook by Turkish mothers and its reasons are related to mothers’ demographic characteristics, anxiety level and perceived social support. It also examined whether mothers’ Facebook use contributes to their perception of their parental role. Methods: Three hundred thirty-two middle-class Turkish mothers who reported to use Facebook completed the demographic information questionnaire, the use of social media questionnaire, the anxiety inventory, the perceived social support scale and the self-perception of parental role questionnaire. Results: Results indicated that Turkish mothers use Facebook more for reasons related to bridging social capital than reasons related to bonding social capital and entertainment. The frequency of using Facebook and the length of time having an account predicted the use of Facebook for reasons related to bridging and bonding social capital. Anxiety level predicted the use of Facebook for reasons related to entertainment. Mothers’ Facebook use was found not to be related to their self-perceived parental competence. Conclusions: The discussion of these findings in terms of Turkish culture implied the need for cross-cultural studies for a better understanding of parents’ use of social network sites.Yayın Cross-group friendships and psychological well-being: A dual pathway through social integration and empowerment(Wiley, 2018-10-01) Bağcı Hemşinlioğlu, Sabahat Çiğdem; Türnüklü, Abbas; Bekmezci, EyüpThis study investigated the associations between cross-group friendships and psychological well-being among a sample of physically disabled adults. A total of 269 disabled people (M-age=39.13, SD=13.80; 114 females, 152 males, 3 unknown) completed questionnaires including the quality of their friendships with non-disabled people, perceived majority group's attitudes towards the minority group, collective self-esteem, collective action tendencies, own outgroup attitudes, and psychological well-being. Findings demonstrated that disabled people's cross-group friendships were directly and indirectly associated with higher levels of psychological well-being via two routes: one by promoting perceived majority attitudes which consequently led to more positive own outgroup attitudes (well-being through social integration hypothesis) and the other by leading to higher levels of collective self-esteem which enhanced collective action tendencies (well-being through empowerment hypothesis). Findings offer important insights into the study of cross-group friendships in relation to the psychological well-being of stigmatized minority group members.Yayın Ethnic identification, discrimination, and mental and physical health among Syrian refugees: The moderating role of identity needs(Wiley, 2017-12) Çelebi, Elif; Verkuyten, Maykel; Bağcı Hemşinlioğlu, Sabahat ÇiğdemUsing a risk and resilience framework and motivated identity construction theory, we investigated the moderating role of identity needs in the association between social identification and perceived discrimination with mental and physical health among a sample of Syrian refugees (N = 361) in Turkey. Results showed that there were two clusters of interrelated identity needs, namely, belonging (belonging, continuity, and esteem) and efficacy (efficacy, meaningfulness, and distinctiveness). Higher perceived ethnic discrimination was found to be associated with poorer mental and physical health but not for respondents who derived a sense of efficacy from their Syrian identity. Higher Syrian identification was associated with lower depression and anxiety but more strongly for refugees who derived a sense of belonging and continuity from their Syrian identity. The findings indicate that investigating the motivational aspects of identity formation is important for understanding when discrimination and group identification undermine or rather contribute to the well-being and health of refugees. These findings are discussed in relation to the growing research on social identities and health.Yayın The comparison of functional connectivity in Parkinson’s Disease patients with and without Parkin gene mutations(Turkish Neuropsychiatric Society, 2025-06-19) Çebi, Merve; Ay, Ulaş; Kıçik, Ani; Erdoğdu, Emel; Tepgeç, Fatih; Uyguner, Zehra Oya; Tüfekçioğlu, Zeynep; Samancı, Bedia; Bilgiç, Başar; Emre, Murat; Demiralp, Tamer; Hanağası, Haşmet AyhanIntroduction: Mapping the functional connectivity of brain regions became appealing in recent research in neurology. Accordingly, a growing body of evidence shows resting-state functional connectivity (rsFC) changes in neurodegenerative disorders including Parkinson’s Disease (PD). As characterised by extensive and progressive dopaminergic loss in the substantia nigra, PD emerges with serious motor and non-motor dysfunctions. In the literature, the minority of PD cases have been associated with certain genetic mutations. The aim of this study was to investigate the rsFC in a group of PD patients having Parkin gene mutation. Method: Twelve PD patients with Parkin mutation (PP-PD), 12 PD patients without Parkin mutation (PN-PD) and 12 healthy controls (HC) were included in the study. All participants underwent a resting-state functional magnetic resonance imaging as well as a neuropsychological assessment and clinical examination. Results: Results indicated that PP-PD had longer disease duration, a higher rate of dyskinesia and lower scores on complex visual perception tests. The resting state networks showed that all PD (consisting of PP-PD and PN-PD) and PP-PD groups had increased functional connectivity in the frontoparietal network as compared to the HC. In addition, the PP-PD group displayed decreased functional connectivity in the dorsal attention network compared to the PN-PD. Conclusion: In conclusion, our data suggests that PD with Parkin gene mutation might be emerging with distinct resting state functional connectivity changes in the brain.
