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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 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 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 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.Yayın A novel approach to non-invasive intracranial pressure wave monitoring: a pilot healthy brain study(Multidisciplinary Digital Publishing Institute (MDPI), 2025-06-28) Karaliunas, Andrius; Bartusis, Laimonas; Krakauskaite, Solventa; Chaleckas, Edvinas; Deimantavicius, Mantas; Hamarat, Yasin; Petkus, Vytautas; Stulge, Toma; Ratkunas, Vytenis; Çelikkaya, Güven; Januleviciene, Ingrida; Ragauskas, ArminasIntracranial pressure (ICP) pulse wave morphology, including the ratios of the three characteristic peaks (P1, P2, and P3), offers valuable insights into intracranial dynamics and brain compliance. Traditional invasive methods for ICP pulse wave monitoring pose significant risks, highlighting the need for non-invasive alternatives. This pilot study investigates a novel non-invasive method for monitoring ICP pulse waves through closed eyelids, using a specially designed, liquid-filled, fully passive sensor system named ‘Archimedes 02’. To our knowledge, this is the first technological approach that enables the non-invasive monitoring of ICP pulse waveforms via closed eyelids. This study involved 10 healthy volunteers, aged 26–39 years, who underwent resting-state non-invasive ICP pulse wave monitoring sessions using the ‘Archimedes 02’ device while in the supine position. The recorded signals were processed to extract pulse waves and evaluate their morphological characteristics. The results indicated successful detection of pressure pulse waves, showing the expected three peaks (P1, P2, and P3) in all subjects. The calculated P2/P1 ratios were 0.762 (SD = ±0.229) for the left eye and 0.808 (SD = ±0.310) for the right eye, suggesting normal intracranial compliance across the cohort, despite variations observed in some individuals. Physiological tests—the Valsalva maneuver and the Queckenstedt test, both performed in the supine position—induced statistically significant increases in the P2/P1 and P3/P1 ratios, supporting the notion that non-invasively recorded pressure pulse waves, measured through closed eyelids, reflect intracranial volume and pressure dynamics. Additionally, a transient hypoemic/hyperemic response test performed in the upright position induced signal changes in pressure recordings from the ‘Archimedes 02’ sensor that were consistent with intact cerebral blood flow autoregulation, aligning with established physiological principles. These findings indicate that ICP pulse waves and their dynamic changes can be monitored non-invasively through closed eyelids, offering a potential method for brain monitoring in patients for whom invasive procedures are not feasible.Yayın Treatment and long-term outcome of mental disorders: The grim picture from a quasi-epidemiological investigation in 54,826 subjects from 40 countries(Elsevier Ireland Ltd, 2025-06) Fountoulakis, Konstantinos N.; Karakatsoulis, Gregory; Abraham, Seri; Adorjan, Kristina; Uddin Ahmed, Helal; Alarcòn, Renato Daniel; Arai, Kiyomi; Auwal, Sani Salihu; Berk, Michael; Levaj, Sarah; Yılmaz Kafalı, HelinIntroduction: This study registered rates of specific treatment options for mental disorders as well as their long-term outcome. Material and methods: The history of mental disorders was used as a proxy for diagnosis. The data came from the COMET-G study (40 countries; 54,826 subjects, 64.73 % females, 35.45±13.51 years old). The analysis included descriptive statistics, Risk Ratios, t-tests, and ANCOVA's. Results: 24.14 % reported a history of any mental disorder (depression >12 %, non-affective psychosis and Bipolar disorder 1 % each, >20 % self-injury, >10 % had attempted suicide, 7.17 % illegal substance abuse). Most patients were not under any kind of treatment (59.44 %) and most were not receiving treatment as recommended (e.g. 90 % of Bipolar and 2/3 of psychotic patients). No treatment at all and psychotherapy as monotherapy were consistently related to poorer outcomes. In anxiety or depression, only antidepressant monotherapy and benzodiazepines, in Bipolar disorder only antipsychotic monotherapy in males and antidepressant monotherapy in females and in non-affective psychosis antipsychotics and psychotherapy in females only, were related to good outcomes. No treatment modality was related to a good outcome in those with a history of self-harm, suicidal attempts, or illegal substance use. Only depression and treatment with antidepressants were related to metabolic syndrome. Discussion: In the community, the overwhelming majority of mental patients do not receive appropriate treatment or, even worse, no treatment at all. The outcome is unfavourable for the majority and only a few selective treatment options seem to make a difference.Yayın Analyzing language ability in first-episode psychosis and their unaffected siblings: a diffusion tensor imaging tract-based spatial statistics analysis study(Elsevier Ltd, 2024-11) Çabuk, Tuğçe; Şahin Çevik, Didenur; Çakmak, Işık Batuhan; Yılmaz Kafalı, Helin; Şenol, Bedirhan; Avcı, Hanife; Karlı Oğuz, Kader; Toulopoulou, TimotheaSchizophrenia (SZ) is a highly heritable mental disorder, and language dysfunctions play a crucial role in diagnosing it. Although language-related symptoms such as disorganized speech were predicted by the polygenic risk for SZ which emphasized the common genetic liability for the disease, few studies investigated possible white matter integrity abnormalities in the language-related tracts in those at familial high-risk for SZ. Also, their results are not consistent. In this current study, we examined possible aberrations in language-related white matter tracts in patients with first-episode psychosis (FEP, N = 20), their siblings (SIB, N = 20), and healthy controls (CON, N = 20) by applying whole-brain Tract-Based Spatial Statistics and region-of-interest analyses. We also assessed language ability by Thought and Language Index (TLI) using Thematic Apperception Test (TAT) pictures and verbal fluency to see whether the scores of these language tests would predict the differences in these tracts. We found significant alterations in language-related tracts such as inferior longitudinal fasciculus (ILF) and uncinate fasciculus (UF) among three groups and between SIB and CON. We also proved partly their relationship with the language test as indicated by the significant correlation detected between TLI Impoverished thought/language sub-scale and ILF. We could not find any difference between FEP and CON. These results showed that the abnormalities, especially in the ILF and UF, could be important pathophysiological vulnerability indexes of schizophrenia. Further studies are required to understand better the role of language as a possible endophenotype in schizophrenia with larger samples.
