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Article Citation - WoS: 22Citation - Scopus: 34A Quality-of-Service-Aware Service Composition Method in the Internet of Things Using a Multi-Objective Fuzzy-Based Hybrid Algorithm(Mdpi, 2023) Hamzei, Marzieh; Khandagh, Saeed; Navimipour, Nima JafariThe Internet of Things (IoT) represents a cutting-edge technical domain, encompassing billions of intelligent objects capable of bridging the physical and virtual worlds across various locations. IoT services are responsible for delivering essential functionalities. In this dynamic and interconnected IoT landscape, providing high-quality services is paramount to enhancing user experiences and optimizing system efficiency. Service composition techniques come into play to address user requests in IoT applications, allowing various IoT services to collaborate seamlessly. Considering the resource limitations of IoT devices, they often leverage cloud infrastructures to overcome technological constraints, benefiting from unlimited resources and capabilities. Moreover, the emergence of fog computing has gained prominence, facilitating IoT application processing in edge networks closer to IoT sensors and effectively reducing delays inherent in cloud data centers. In this context, our study proposes a cloud-/fog-based service composition for IoT, introducing a novel fuzzy-based hybrid algorithm. This algorithm ingeniously combines Ant Colony Optimization (ACO) and Artificial Bee Colony (ABC) optimization algorithms, taking into account energy consumption and Quality of Service (QoS) factors during the service selection process. By leveraging this fuzzy-based hybrid algorithm, our approach aims to revolutionize service composition in IoT environments by empowering intelligent decision-making capabilities and ensuring optimal user satisfaction. Our experimental results demonstrate the effectiveness of the proposed strategy in successfully fulfilling service composition requests by identifying suitable services. When compared to recently introduced methods, our hybrid approach yields significant benefits. On average, it reduces energy consumption by 17.11%, enhances availability and reliability by 8.27% and 4.52%, respectively, and improves the average cost by 21.56%.Article Citation - WoS: 145Citation - Scopus: 145Psychological Correlates of Covid-19 Conspiracy Beliefs and Preventive Measures: Evidence From Turkey(Springer, 2020) Alper, Sinan; Bayrak, Fatih; Yılmaz, OnurcanCOVID-19 pandemic has led to popular conspiracy theories regarding its origins and widespread concern over the level of compliance with preventive measures. In the current preregistered research, we recruited 1088 Turkish participants and investigated (a) individual differences associated with COVID-19 conspiracy beliefs; (2) whether such conspiracy beliefs are related to the level of preventive measures; and (3) other individual differences that might be related to the preventive measures. Higher faith in intuition, uncertainty avoidance, impulsivity, generic conspiracy beliefs, religiosity, and right-wing ideology, and a lower level of cognitive reflection were associated with a higher level of belief in COVID-19 conspiracy theories. There was no association between COVID-19 conspiracy beliefs and preventive measures while perceived risk was positively and impulsivity negatively correlated with preventive measures. We discuss the implications and directions for future research.Article Citation - WoS: 21Citation - Scopus: 20"it Was as If Society Didn't Want a Woman To Get an Abortion": a Qualitative Study in Istanbul Turkey(Elsevier Science Inc, 2017) MacFarlane, Katrina A.; O'Neil, Mary Lou; Tekdemir, Deniz; Foster, Angel M.Introduction: In 1983 abortion without restriction as to reason was legalized in Turkey. However at an international conference in 2012 the Prime Minister condemned abortion and announced his intent to draft restrictive abortion legislation. As a result of public outcry and protests the law was not enacted but media reports suggest that barriers to abortion access have since worsened. Objectives: We aimed to conduct a qualitative study exploring women's recent abortion experiences in Istanbul Turkey. Study design: In 2015 we conducted 14 semi-structured in-depth interviews with women aged 18 or older who had obtained abortion care in Istanbul on/after January 1 2009. We employed a multimodal recruitment strategy and analyzed these interviews for content and themes using deductive and inductive techniques. Results: Women reported on a total of 19 abortions. Although abortion care is available in private facilities only one public hospital provides abortion services without restriction as to reason. Women who had multiple abortions in different facility types described quality of care more positively in the private sector. Unmarried women considered their marital status when making the decision to seek an abortion and reported challenges obtaining comprehensive sexual and reproductive health services. All participants were familiar with the Turkish government's antiabortion discourse and believed that this was reflective of an overarching desire to restrict women's rights. Conclusion: Public abortion services in Istanbul are currently limited and private abortion services are accessible but relatively expensive to obtain. Recent antiabortion political rhetoric appears to have negatively impacted access and service quality. Implications: This is the first qualitative study exploring women's experiences obtaining abortion services in Turkey since the proposed abortion restriction in 2012. Further research exploring the experiences of unmarried women and abortion accessibility in other regions of the country is warranted. (C) 2017 Elsevier Inc. All rights reserved.Article Citation - WoS: 5Citation - Scopus: 4The Availability of Emergency Contraception From Family Health Centers in Turkey(Elsevier Ireland Ltd, 2022) O'Neil, Mary Lou; Aldanmaz, Bahar; Altuntas, DenizReproductive health care, including contraception, is a fundamental aspect of any public health care system and it is important to reduce barriers to access to all forms of contraception, including emergency contraception. In recent years, the rhetoric of pronatalism in Turkey has come to dominate and raises questions about the availability of reproductive health care services, in particular contraception, from state run facilities. This study aimed to determine the availability of dedicated emergency contraception (EC) from government run Family Health Centers (FHCs) in Turkey. In 2019, a team of trained researchers called a random sample of 583 FHCs located in the largest cities in twelve regions across Turkey asking for dedicated EC. Dedicated EC is largely unavailable from government supported FHCs. Only 6.1% stated that they provided EC while 53.8% stated that it was not available and that they could provide no alternative. A further 28.3% declared that they could provide an alternative to dedicated EC that almost always consisted of oral contraceptives. We found statistically significant variations in response rate and availability among cities as well as the rate of referral to pharmacies. There is little access to EC from government sponsored health clinics designated to provide family planning services, which hinders access to an essential reproductive health care service that should be available to women everywhere.Article Citation - WoS: 27Citation - Scopus: 26Network Structural Origin of Instabilities in Large Complex Systems(Amer Assoc Advancement Science, 2022) Duan, Chao; Nishikawa, Takashi; Eroglu, Deniz; Motter, Adilson E.A central issue in the study of large complex network systems, such as power grids, financial networks, and ecological systems, is to understand their response to dynamical perturbations. Recent studies recognize that many real networks show nonnormality and that nonnormality can give rise to reactivity-the capacity of a linearly stable system to amplify its response to perturbations, oftentimes exciting nonlinear instabilities. Here, we identify network structural properties underlying the pervasiveness of nonnormality and reactivity in real directed networks, which we establish using the most extensive dataset of such networks studied in this context to date. The identified properties are imbalances between incoming and outgoing network links and paths at each node. On the basis of this characterization, we develop a theory that quantitatively predicts nonnormality and reactivity and explains the observed pervasiveness. We suggest that these results can be used to design, upgrade, control, and manage networks to avoid or promote network instabilities.Article Citation - WoS: 2Jejunojejunal Intussusception Secondary To Lipoma in an Adult -: a Case Report(Blackwell Munksgaard, 2002) Çakirer, S; Sirvanci, M; Duran, CLipoma is a rare cause of adult intussusception. We present the CT findings of an adult patient with jejunojejunal intussusception secondary to submucosal lipoma as the lead point in this case report.Article Citation - Scopus: 1Understanding the Dynamics of Compliance To Smoke-Free Policy Regulations: Exploring the Perspectives of Venue Owners and Staff in Türkiye(European Publishing, 2024) Baltaci, Ezgi; Carkoglu, Asli; Saraf, Sejal; Ergueder, Toker; Ergoer, Guel; Hayran, Mutlu; Hoe, ConnieINTRODUCTION The study aims to understand the facilitators and barriers associated with enforcing and complying with Turkiye's smoke-free policy from the perspective of hospitality venue owners and employees. METHODS A qualitative open-ended survey was conducted in Istanbul and Ankara in 2021 with 58 respondents from 3 different districts in each city from four types of venues: restaurants, traditional coffee and waterpipe houses, and European-style cafes. The open-ended survey included questions to understand the knowledge, beliefs, and attitudes of respondents about Turkiye's smoke-free policy and their perceptions of the facilitators and/or barriers to smoke-free policy implementation and changes after COVID-19. The data were analyzed using an inductive approach to identify patterns and categorize the data into themes. RESULTS The respondents expressed that the smoke-free policy aimed to protect employees and customers from secondhand smoke (SHS), respect human health, and improve air quality. Findings suggest that the positive attitude of venue owners and staff toward the smoke-free policy serves as a facilitator. However, fear of financial impact, customers' negative attitudes, difficulties in meeting physical requirements, and insufficient enforcement were found to be barriers to implementing the smoke-free policy. The effects of the COVID-19 pandemic were reported as an initial increase in compliance and awareness among customers and staff, but some respondents noted negative changes due to the emotional and financial effects of prolonged restrictions. These challenges have led to decreased attention on the smoke-free policy among venue owners, staff and customers. Respondents' suggested improvements were related to building infrastructure, such as the ventilation systems and educating the public on the harmful health effects of smoking. CONCLUSIONS Despite the general understanding of the dangers of secondhand smoke and the smoke-free policy, this study highlights the challenges in implementing smoke-free policy measures and the continued need to raise awareness about the importance of a 100% smoke-free venue. A comprehensive approach to addressing the tobacco epidemic as a multifaceted public health issue is essential.Article Citation - WoS: 1Citation - Scopus: 1The Role of Pyranine in Characterization of Paam-Kappa C Composites by Using Fluorescence Technique(Springer/Plenum Publishers, 2011) Evingür, Gülşen Akın; Pekcan, ÖnderPolyacrylamide (PAAm) doped by kappa-carrageenan (kappa C) gels were prepared with various amounts of kappa C varying in the range between 0 wt.% and 3 wt.%. Steady-state fluorescence (SSF) technique was employed for studying sol-gel transition and swelling of PAAm-kappa C composite gels which were prepared by free-radical crosslinking copolymerization. Pyranine was introduced as a fluorescence probe. Pyranine molecules start to bind to acrylamide polymer chains upon the initiation of the polymerization thus the spectra of the bonded pyranines shift to the shorter wavelengths. Fluorescence spectra from the bonded pyranines allow one to monitor the sol-gel transition and to test the universality of the sol-gel transition as a function of some kinetic parameters like polymer concentration. Observations around the gel point t (c) for PAAm-kappa C composite gels showed that the gel fraction exponent beta obeyed the percolation result for low kappa C (< 2.0 wt. %) however classical results were produced at higher kappa C (> 2.0 wt.%). On the other hand fluorescence intensity of pyranine was measured during in situ swelling process at various amounts of kappa C and it was observed that fluorescence intensity values decreased as swelling is proceeded. Li-Tanaka equation was used to determine the swelling time constants tau and cooperative diffusion coefficients D.Article Citation - WoS: 1Citation - Scopus: 2Can Reflection Mitigate Covid-19 Vaccine Conspiracy Beliefs and Hesitancy(Routledge, 2025) Bayrak, F.; Kayatepe, E.; Özman, N.; Yilmaz, O.; Isler, O.; Saribay, S.A.Objective design: Periods of social turmoil, such as the COVID-19 pandemic, tend to amplify conspiracy beliefs, evidenced by increased vaccine hesitancy. Despite this trend, effective interventions targeting vaccine-related conspiracy beliefs remain scarce, partly due to underexplored cognitive processes. Three competing theoretical accounts offer differing predictions about the role of reflective thinking in supporting conspiracy beliefs: the Motivated Reasoning Account suggests reflection strengthens commitment to pre-existing attitudes; the Reflective Reasoning Account posits that reflection enhances belief accuracy; and the Reflective Doubt Account proposes reflection fosters general scepticism. Main outcome measures: Utilising open science practices and a validated technique to activate reflection, we conducted an experimental investigation with a diverse sample (N = 1483) segmented by vaccine attitudes. We investigated the impact of reflection on specific and generic COVID-19 conspiracy beliefs and vaccine-support behaviours across pro-vaccine, neutral, and vaccine-hesitant groups, while examining the moderating effects of scientific literacy, intellectual humility, and actively open-minded thinking. Results: The confirmatory analysis provided no direct support for the theoretical predictions. However, findings indicated that intellectual humility significantly moderated the effect of reflection, enhancing vaccine-support behaviour among participants with high intellectual humility, highlighting the complex interplay of cognitive style and prior attitudes in shaping responses to conspiracy beliefs and vaccine-support actions. Conclusion: The study highlights that while reflective thinking alone did not directly influence vaccine support behavior, its positive effect emerged among individuals with higher intellectual humility, emphasizing the importance of individual differences in shaping belief-related outcomes. © 2025 Informa UK Limited, trading as Taylor & Francis Group.Article Citation - Scopus: 4Jejunojejunal intussusception secondary to lipoma in an adult: a case report(Blackwell Munksgaard, 2002) Çakırer, Sinan; Şırvancı, Mustafa; Duran, CihanLipoma is a rare cause of adult intussusception. We present the CT findings of an adult patient with jejunojejunal intussusception secondary to submucosal lipoma as the lead point in this case report.Article Citation - WoS: 1Citation - Scopus: 1Gamifying Haptics User Studies: Comparison of Response Times From Smartphone Interfaces(IEEE Computer Soc, 2025) Kudsi, Bushra; Xu, Doris; Sen, Umit; Yoshida, Kyle T.; Stroppa, Fabio; Nunez, Cara M.; Sarac, MineHaptics user studies are often restricted to a set, physical location and use methods that do not captivate the user. Applying game design elements can create an entertaining environment and increase user engagement. Using ubiquitous tools, like smartphones, to conduct haptics user studies could allow researchers to access larger participant groups while a gamified approach could facilitate the data collection by making the experiment more enjoyable. To explore this concept, this work presents a gamified version of an existing psychophysical experiment that investigates response time to multisensory cues using a smartphone based on "Whac-A-Mole". We conducted a user study to compare our gamified interface with an existing psychophysical interface with thirteen participants exploring the response time from eighteen combinations of auditory, haptic, and visual stimuli at different levels of intensities and participant preferences for both interfaces. The results demonstrate that the gamified interface successfully captured similar trends in response times and significantly elevated participant enjoyment ($p < 0.003$), but did not result in equivalent response times to the original interface. This work shows the benefits and drawbacks of following a gamification approach when designing haptics user studies and discusses factors and trade-offs to consider when gamifying studies.Article Citation - WoS: 6Citation - Scopus: 7Drying of Polyacrylamide Composite Gels Formed With Various Kappa- Carrageenan Content(Springer/Plenum Publishers, 2011) Evingür, Gülşen Akın; Pekcan, ÖnderDrying of polyacrylamide (PAAm)-kappa-carrageenan (kappa C) composite gels were monitored by using steady-state fluorescence technique. Disc shaped gels were formed from acrylamide (AAm) and N N'- methylenebisacrylamide(Bis) with various kappa- carrageenan (kappa C) contents by free radical crosslinking copolymerization in water. Pyranine (P) was doped as a fluorescence probe and scattered light I (sc) and fluorescence intensities I were monitored during drying of these gels. It is observed that fluorescence intensity of pyranine increased as drying time is increased for all samples. The increase in I was modeled using Stern- Volmer equation and diffusion with moving boundary. It is found that desorption coefficient D decreased as kappa C contents were increased. Supporting gravimetrical and volumetric experiments were also carried out during drying of PAAm- kappa C composite gels.Article Citation - WoS: 6Citation - Scopus: 5A new triazolothiadiazine derivative inhibits stemness and induces cell death in HCC by oxidative stress dependent JNK pathway activation(Nature Portfolio, 2022) Kahraman, Deniz Cansen; Guven, Ebru Bilget; Aytac, Peri S.; Aykut, Gamze; Tozkoparan, Birsen; Atalay, Rengul CetinHepatocellular carcinoma (HCC) is a highly heterogeneous cancer, and resistant to both conventional and targeted chemotherapy. Recently, nonsteroidal anti-inflammatory drugs (NSAIDs) have been shown to decrease the incidence and mortality of different types of cancers. Here, we investigated the cellular bioactivities of a series of triazolothiadiazine derivatives on HCC, which have been previously reported as potent analgesic/anti-inflammatory compounds. From the initially tested 32 triazolothiadiazine NSAID derivatives, 3 compounds were selected based on their IC50 values for further molecular assays on 9 different HCC cell lines. 7b, which was the most potent compound, induced G2/M phase cell cycle arrest and apoptosis in HCC cells. Cell death was due to oxidative stress-induced JNK protein activation, which involved the dynamic involvement of ASK1, MKK7, and c-Jun proteins. Moreover, 7b treated nude mice had a significantly decreased tumor volume and prolonged disease-free survival. 7b also inhibited the migration of HCC cells and enrichment of liver cancer stem cells (LCSCs) alone or in combination with sorafenib. With its ability to act on proliferation, stemness and the migration of HCC cells, 7b can be considered for the therapeutics of HCC, which has an increased incidence rate of similar to 3% annually.Article Optimizing Neuron Simulation Environment Using Remote Memory Access With Recursive Doubling on Distributed Memory Systems(Hindawi Ltd, 2016) Shehzad, Danish; Bozkuş, ZekiIncrease in complexity of neuronal network models escalated the efforts to make NEURON simulation environment efficient. The computational neuroscientists divided the equations into subnets amongst multiple processors for achieving better hardware performance. On parallel machines for neuronal networks interprocessor spikes exchange consumes large section of overall simulation time. In NEURON for communication between processors Message Passing Interface (MPI) is used. MPI Allgather collective is exercised for spikes exchange after each interval across distributed memory systems. The increase in number of processors though results in achieving concurrency and better performance but it inversely affects MPI Allgather which increases communication time between processors. This necessitates improving communication methodology to decrease the spikes exchange time over distributed memory systems. This work has improved MPI Allgather method using Remote Memory Access (RMA) by moving two-sided communication to one-sided communication and use of recursive doubling mechanism facilitates achieving efficient communication between the processors in precise steps. This approach enhanced communication concurrency and has improved overall runtime making NEURON more efficient for simulation of large neuronal network models.Article Citation - WoS: 32Citation - Scopus: 37Effect of low-dose methyl prednisolone on serum cytokine levels following extracorporeal circulation(Arnold Hodder Headline Plc., 1999) Yılmaz, Mert; Ener, Serdar; Akalın, Halis; Sağdıç, Kadir; Serdar, O. Akin; Cengiz, MeteThe systemic inflammatory response to cardiopulmonary bypass (CPB) is associated with increased production of cytokines. This systemic inflammatory response characterized by the activation of interleukin-6 (IL-6) and interleukin-8 (IL-8) during and after CPB is well documented. A prospective randomized double-blind study was performed so as to understand the effects of low-dose methyl prednisolone sodium succinate (MPSS) on the circulating levels of serum cytokines and clinical outcome. Twenty patients were randomly divided into two groups on the basis of the administration of low-dose(1 mg/kg) MPSS in = 10) and placebo in = 10) into the pump prime solution. All patients were scheduled to undergo a primaryArticle Citation - WoS: 21Citation - Scopus: 24How People Can Become Persuaded by Weak Messages Presented by Credible Communicators: Not All Sleeper Effects Are Created Equal(Academic Press Inc Elsevier Science, 2017) Albarracin, Dolores; Kumkale, Gökçe Tarcan; Vento, Patrick Poyner-DelThe sleeper effect has been proposed to describe temporal changes in persuasion for messages associated with noncredible sources. The present research introduces a new kind of sleeper effect denoting increases in persuasion for weak messages associated with credible sources. This effect of the source was hypothesized to derive from attending to the message source rather than the message arguments and reconstructing delayed attitudes primarily on the basis of the source information. Findings from three experiments revealed that when the focus of attention was the communicator there was a sleeper effect for the source. Specifically during the time between an immediate follow up and a delayed follow up persuasion increased when credible sources presented weak arguments. In contrast when the focus of attention was the message arguments a traditional sleeper effect emerged. That is persuasion increased when strong arguments were presented by a noncredible communicator. These effects were mediated by relative recall of arguments versus source attributes and replicated with different message topics and lengths of delay. (C) 2016 Published by Elsevier Inc.Article Citation - WoS: 54Citation - Scopus: 66Synthesis Molecular Modeling in Vivo Study and Anticancer Activity of 124-Triazole Containing Hydrazide-Hydrazones Derived From (s)-Naproxen(Wiley-VCH Verlag GmbH, 2019) Han, Muhammed İhsan; Bekçi, Hatice; Uba, Abdullahi İbrahim; Yıldırım, Yeliz; Karasulu, Ercüment; Cumaoğlu, Ahmet; Karasulu, Hatice Y.; Yelekçi, Kemal; Yılmaz, Ozguer; Küçükgüzel, Şükriye GünizA new series of 124-triazole containing hydrazide-hydrazones derived from (S)-naproxen (7a-m) was synthesized in this study. The structures of these compounds were characterized by spectral (Fourier-transform infrared spectroscopy H-1-nuclear magnetic resonance (NMR) C-13-NMR and high-resolution electron ionization mass spectrometry) methods. Furthermore molecular modeling of these compounds was studied on human methionine aminopeptidase-2. All synthesized compounds were screened for anticancer activity against three prostate cancer cell lines (PC3 DU-145 and LNCaP) using the 3-(45-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium colorimetric method. Compound 7a showed the best activity against the PC3 DU-145 and LNCaP cancer cell lines with IC50 values of 26.0 34.5 and 48.8 mu M respectively. Compounds 7b 7k and 7m showed anticancer activity against cancer cell lines PC3 and DU-145 with IC50 values of 43.0 36.5 29.3 mu M and 49.8 49.1 31.6 mu M respectively. Compounds 7f and 7g showed anticancer activity against PC3 cells with IC50 values of 43.4 and 34.5 mu M respectively. To assess the biodistribution in mice of IRDye800 dye-labeled compound 7a or 100 mu M of free dye was injected intravenously into the mice's tail. In vivo images were taken with in vivo imaging system spectrum device at 60 120 180 240 300 and 360 min after injection. At the end of 360 min ex vivo studies were carried out to determine in which organs the dye was accumulated in the urogenital system. Ex vivo studies showed that the accumulation of compound 7a in the prostate is greater than that of the free dye and it is concluded that compound 7a may be promising for the treatment of prostate cancer..Article Citation - WoS: 10Citation - Scopus: 10Ligand-Binding Affinity of Alternative Conformers of Human Beta(2)-Adrenergic Receptor in the Presence of Intracellular Loop 3 (icl3) and Their Potential Use in Virtual Screening Studies(Wiley, 2019) Dilcan, Gonca; Doruker, Pemra; Akten, Ebru DemetThis study investigates the structural distinctiveness of orthosteric ligand-binding sites of several human beta(2) adrenergic receptor (beta(2)-AR) conformations that have been obtained from a set of independent molecular dynamics (MD) simulations in the presence of intracellular loop 3 (ICL3). A docking protocol was established in order to classify each receptor conformation via its binding affinity to selected ligands with known efficacy. This work's main goal was to reveal many subtle features of the ligand-binding site presenting alternative conformations which might be considered as either active- or inactive-like but mostly specific for that ligand. Agonists inverse agonists and antagonists were docked to each MD conformer with distinct binding pockets using different docking tools and scoring functions. Mostly favored receptor conformation persistently observed in all docking/scoring evaluations was classified as active or inactive based on the type of ligand's biological effect. Classified MD conformers were further tested for their ability to discriminate agonists from inverse agonists/antagonists and several conformers were proposed as important targets to be used in virtual screening experiments that were often limited to a single X-ray structure.Article Citation - WoS: 3Citation - Scopus: 3The Neural Gamma(2)alpha(1)beta(2)alpha(1)beta(2) Gamma Amino Butyric Acid Ion Channel Receptor: Structural Analysis of the Effects of the Ivermectin Molecule and Disulfide Bridges(Springer, 2018) Ayan, Meral; Eşsiz, ŞebnemWhile similar to 30% of the human genome encodes membrane proteins only a handful of structures of membrane proteins have been resolved to high resolution. Here we studied the structure of a member of the Cys-loop ligand gated ion channel protein superfamily of receptors human type A gamma(2)alpha(1)beta(2)alpha(1)beta(2) gamma amino butyric acid receptor complex in a lipid bilayer environment. Studying the correlation between the structure and function of the gamma amino butyric acid receptor may enhance our understanding of the molecular basis of ion channel dysfunctions linked with epilepsy ataxia migraine schizophrenia and other neurodegenerative diseases. The structure of human gamma(2)alpha(1)beta(2)alpha(1)beta(2) has been modeled based on the X-ray structure of the Caenorhabditis elegans glutamate-gated chloride channel via homology modeling. The template provided the first inhibitory channel structure for the Cys-loop superfamily of ligand-gated ion channels. The only available template structure before this glutamate-gated chloride channel was a cation selective channel which had very low sequence identity with gamma aminobutyric acid receptor. Here our aim was to study the effect of structural corrections originating from modeling on a more reliable template structure. The homology model was analyzed for structural properties via a 100 ns molecular dynamics (MD) study. Due to the structural shifts and the removal of an open channel potentiator molecule ivermectin from the template structure helical packing changes were observed in the transmembrane segment. Namely removal of ivermectin molecule caused a closure around the Leu 9 position along the ion channel. In terms of the structural shifts there are three potential disulfide bridges between the M1 and M3 helices of the gamma(2) and 2 alpha(1) subunits in the model. The effect of these disulfide bridges was investigated via monitoring the differences in root mean square fluctuations (RMSF) of individual amino acids and principal component analysis of the MD trajectory of the two homology models-one with the disulfide bridge and one with protonated Cys residues. In all subunit types RMSF of the transmembrane domain helices are reduced in the presence of disulfide bridges. Additionally loop A loop F and loop C fluctuations were affected in the extracellular domain. In cross-correlation analysis of the trajectory the two model structures displayed different coupling in between the M2-M3 linker region protruding from the membrane and the beta 1-beta 2/D loop and cys-loop regions in the extracellular domain. Correlations of the C loop which collapses directly over the bound ligand molecule were also affected by differences in the packing of transmembrane helices. Finally more localized correlations were observed in the transmembrane helices when disulfide bridges were present in the model. The differences observed in this study suggest that dynamic coupling at the interface of extracellular and ion channel domains differs from the coupling introduced by disulfide bridges in the transmembrane region. We hope that this hypothesis will be tested experimentally in the near future.Article Citation - WoS: 1Citation - Scopus: 2Decoding cultural conflicts(Frontiers Media Sa, 2023) Kocak, Ozgecan; Puranam, Phanish; Yegin, AfsarAs pioneers of the Carnegie Perspective recognized, conflicts in organizations can exist even when incentives of all parties are aligned. These can often be traced to differences in cognitions such as beliefs and values, which are foundational components of any given culture. This paper refines the operationalization of cultural clashes by identifying differences in beliefs about causality (which actions cause which outcomes) and morality (in the broad sense of what is evaluated as desirable) as two fundamental sources of conflict. In our first study, we demonstrate empirically that participants recognize and distinguish between these two sources of conflict. In our second study, we test the hypotheses that while misalignments in either causal or moral codes increase observers' perceptions of relationship conflict, negative affect, likelihood of avoidance, and lower perceived likelihood of conflict resolution, the effects are stronger for misalignments in moral codes than misalignments in causal codes and strongest when both causal and moral codes are misaligned. We test these arguments using vignette-based experimental studies. Our findings support our hypotheses. This research has significant implications for the understanding of conflict dynamics within and beyond organizational contexts. By recognizing the pivotal role of cultural differences in shaping conflicts, organizations and decision-makers can better anticipate, manage, and potentially preempt such conflicts.
