Motivation to Lead and Shared Leadership in Teams

Zeynep Giraylar(Zeynep Giraylar ),Kyoosang Choi(Kyoosang Choi) 한국자료분석학회 2023 Journal of the Korean Data Analysis Society Vol.25 No.1

More companies have started to adopt a model of self-managed team as their primary work design. As work environments get more complex, an appointed leader alone cannot fulfill all the necessary leadership responsibilities of a team. In this manner, the shared leadership within a team is of great importance for today's work environments. The primary purpose of the present study was to examine an antecedent of shared leadership. Focusing on leadership motivation, this study investigated how team members’ motivation to lead affects shared leadership of the team. This study also examined the effects of shared leadership on team performance using an objective team performance measure, which little previous studies have investigated. Data were obtained from 57 teams consisting of 3 to 5 members. They performed a computer-based business strategy game. Findings showed that the teams consisting of members with a high level of motivation to lead scores were positively related to shared leadership and shared leadership significantly predicted team performance. Theoretical and practical implications of this study are also discussed.

Influence of modeling agents on the surface properties of an esthetic nano-hybrid composite

Kutuk, Zeynep Bilge,Erden, Ecem,Aksahin, Damla Lara,Durak, Zeynep Elif,Dulda, Alp Can The Korean Academy of Conservative Dentistry 2020 Restorative Dentistry & Endodontics Vol.45 No.1

Objective: The aim of this study was to evaluate the influence of different modeling agents on the surface microhardness (Vickers hardness number; VHN), roughness (Ra), and color change (ΔE) of a nano-hybrid composite with or without exposure to discoloration by coffee. Materials and Methods: Sixty-four cylinder-shaped nano-hybrid composite specimens were prepared using a Teflon mold. The specimens' surfaces were prepared according to the following groups: group 1, no modeling agent; group 2, Modeling Liquid; group 3, a universal adhesive (G-Premio Bond); and group 4, the first step of a 2-step self-adhesive system (OptiBond XTR). Specimens were randomly allocated into 2 groups (n = 8) according to the storage medium (distilled water or coffee). VHN, Ra, and ΔE were measured at 24 hours, 1 week, and 6 weeks. The Kruskal-Wallis test followed by the Bonferroni correction for pairwise comparisons was used for statistical analysis (α = 0.05). Results: Storage time did not influence the VHN of the nano-hybrid composite in any group (p > 0.05). OptiBond XTR Primer application affected the VHN negatively in all investigated storage medium and time conditions (p < 0.05). Modeling Liquid application yielded improved Ra values for the specimens stored in coffee at each time point (p < 0.05). Modeling Liquid application was associated with the lowest ΔE values in all investigated storage medium and time conditions (p < 0.05). Conclusion: Different types of modeling agents could affect the surface properties and discoloration of nano-hybrid composites.

Influence of modeling agents on the surface properties of an esthetic nano-hybrid composite

Kutuk Zeynep Bilge,Erden Ecem,Aksahin Damla Lara,Durak Zeynep Elif,Dulda Alp Can 대한치과보존학회 2020 Restorative Dentistry & Endodontics Vol.45 No.2

Objective: The aim of this study was to evaluate the influence of different modeling agents on the surface microhardness (Vickers hardness number; VHN), roughness (Ra), and color change (ΔE) of a nano-hybrid composite with or without exposure to discoloration by coffee. Materials and Methods: Sixty-four cylinder-shaped nano-hybrid composite specimens were prepared using a Teflon mold. The specimens' surfaces were prepared according to the following groups: group 1, no modeling agent; group 2, Modeling Liquid; group 3, a universal adhesive (G-Premio Bond); and group 4, the first step of a 2-step self-adhesive system (OptiBond XTR). Specimens were randomly allocated into 2 groups (n = 8) according to the storage medium (distilled water or coffee). VHN, Ra, and ΔE were measured at 24 hours, 1 week, and 6 weeks. The Kruskal-Wallis test followed by the Bonferroni correction for pairwise comparisons was used for statistical analysis (α = 0.05). Results: Storage time did not influence the VHN of the nano-hybrid composite in any group (p > 0.05). OptiBond XTR Primer application affected the VHN negatively in all investigated storage medium and time conditions (p < 0.05). Modeling Liquid application yielded improved Ra values for the specimens stored in coffee at each time point (p < 0.05). Modeling Liquid application was associated with the lowest ΔE values in all investigated storage medium and time conditions (p < 0.05). Conclusion: Different types of modeling agents could affect the surface properties and discoloration of nano-hybrid composites.

Comparison of recovery profiles of propofol and sevoflurane anesthesia with bispectral index monitoring in percutaneous nephrolithotomy

Zeynep Nur Orhon,Sibel Devrim,Melek Celik,Yekbun Dogan,Asif Yildirim,Erem Kaan Basok 대한마취통증의학회 2013 Korean Journal of Anesthesiology Vol.64 No.3

Background: The aim of the study was to evaluate the comparative effects of propofol infusion versus sevoflurane for maintenance of anesthesia with respect to hemodynamics, recovery characteristics, nausea and vomiting in patients undergoing percutaneous nephrolithotomy. Methods: Forty American Society of Anesthesiologists physical status I-II patients, aged between 22 and 65 years were randomly divided to receive either intravenous anesthesia with propofol (group P) or sevoflurane (group S). Cardiovascular variables, peripheral oxygen saturation (SpO2), end-tidal carbon dioxide (ETCO2), bispectral index (BIS) and train-of-four (TOF) values were recorded at intervals throughout the procedure. Time to spontaneous respiration, eye opening, extubation, obey commands, hand squeezing, Aldrete Score > 9 and the incidence of postoperative nausea and vomiting were recorded. Results: Early recovery times [spontaneous respiration (P = 0.002), eye opening (P = 0.006), extubation (P = 0.013), obey commands (P < 0.05), hand squeezing (P = 0.005)] were significantly longer in group P. The incidence of vomiting was significantly higher in group S (P < 0.05). Hemodynamic parameters, levels of SpO2, ETCO2, and BIS and TOF values were not significantly different between the groups (P > 0.05). Conclusions: The present study which adjusted sevoflurane concentration and propofol infusion rate according to BIS values revealed that maintenance of anesthesia with sevoflurane is associated with faster recovery than anesthesia with propofol. Propofol resulted in a significantly lower incidence of postoperative nausea and vomiting. Hemodynamic parameters and levels of SpO2 and ETCO2 were comparable between the groups during percutaneous nephrolithotomy.

Fashion consumption during economic crisis: Emerging practices and feelings of consumers

Zeynep Ozdamar Ertekin,Bengu Sevil Oflac,Cemre Serbetcioglu 한국마케팅과학회 2020 Journal of Global Fashion Marketing Vol.11 No.3

Economic crisis has a significant impact on consumption practices and the way consumers justify their consumption patterns. Particularly in the field of fashion, consumers face a conflict between desire to consume due to rapidly changing fashion trends and coping with the decrease in purchasing power due to the economic crisis. Semi-structured interviews were carried out to gain a deeper understanding of how the economic crisis affects consumers’ fashion consumption behavior and the alternative consumption practices that emerge. The research further sheds light on the underlying feelings involved due to changes in consumption patterns. Some of the themes that emerge—reuse, reduce, and reject—are in line with earlier findings on anti-consumption but this time the motives of the consumers are non-voluntary. The findings also contribute to anti-consumption literature by introducing three new themes: refind alternative channels, reconsider, and rely on discounts. The study further shows that there are both positive and negative feelings associated with changes in consumption behavior due to economic crisis. Along with understanding the adaptations in consumption behavior, anticipating these conflicting emotions resulting from crisis related anti-consumption is important for marketers and retailers who are concerned about developing appropriate responsive strategies.

Epidural anesthesia for pilonidal sinus surgery: ropivacaine versus levobupivacaine

Zeynep Nur Orhon,Emine Nursen Koltka,Sibel Devrim,Sevil Tüfekçi,Serkan Doğru,Melek Çelik 대한마취통증의학회 2015 Korean Journal of Anesthesiology Vol.68 No.2

Background: Epidural anesthesia is one of the best options for lower abdominal and lower limb surgery. However, therehave been insufficient reports regarding the use of epidural anesthesia for pilonidal sinus surgery. The present study wasperformed to compare the clinical profiles of epidural block performed with 0.75% levobupivacaine and 0.75% ropivacainein this procedure. Methods: Thirty patients undergoing pilonidal sinus surgery were randomly allocated into two groups: one group receivedlevobupivacaine and the other received ropivacaine at 0.75% in a volume of 10 ml. Arterial blood pressure, heartrate, oxygen saturation, the onset time of analgesia and duration of block, highest sensory block level, perioperative andpostoperative side effects, and patients’ and surgeons’ satisfaction were recorded. Results: Hemodynamic stability was maintained in both groups throughout surgery. The onset time of analgesia (thetime from epidural injection of local anesthetic to reach L2 sensorial block) was 6.26 ± 3.49 min in the levobupivacainegroup and 4.06 ± 1.75 min in the ropivacaine group (P = 0.116). The duration of sensorial block (time for regression ofsensory block to L2) was 297.73 ± 70.94 min in group L and 332.40 ± 102.22 min in group R (P = 0.110). Motor block wasnot seen in any of the patients in the study groups. Patients’ and surgeons’ satisfaction with the anesthetic technique weremostly excellent in both groups. Conclusions: In patients undergoing pilonidal sinus surgery, both levobupivacaine and ropivacaine produce rapid andexcellent epidural block without leading to motor block or significant side effects. Although not statistically significant,the onset time of anesthesia was shorter and the duration of effect was longer with ropivacaine than with levobupivacainein this study.

Fabrication of Antibacterial Polyhydroxybutyrate/Lauric Acid Composite Membranes for Guided Bone Regeneration

Zeynep Karahaliloglu,Ebru Kilicay 한국섬유공학회 2022 Fibers and polymers Vol.23 No.6

Guided tissue (GTR) and guided bone regeneration (GBR) are well-established surgical procedures in orthopedicsand dentistry. Recently, the most prevalent reason of unsuccessful GBR membranes-mediated tissue regeneration is infection. Several antibiotics have been frequently used to overcome this problem. Further, the antibiotic resistance limits theirprofitability, and therefore, alternative antibacterial GBR membranes are highly in demand. With this focus, the goal of thestudy was to develop a novel antibacterial GBR membrane composed of a Poly[(R)-3-hydroxybutyric acid] (PHB) fibrillarmembrane loaded with lauric acid (LA) for bone regeneration. New type of GBR composite membranes were fabricated byPHB/LA composite fibers with three different PHB to LA ratios (PHB:LA=98:2, 90:10, and 80:20, wt%) via electrospinning. Atomic force microscopy (AFM) results of the membranes showed that surface roughness values increased twofold in20 wt% LA added membrane compared with the pure PHB. On the other hand, colony counting test results implied that100PHB/LA caused a significant reduction in the amount of viable S. aureus and E. coli, (7.3 and 8.6 log CFU/ml) ascompared to the pure PHB (10.1 and 10.9 log CFU/ml), respectively (p<0.05). Hence, it can be concluded that electrospunPHB/LA composite membranes provide great antibacterial effects against two bacteria species while closely mimickingphysiological bone environment through their surface properties.

The Effect of Stinging Nettle (Urtica dioica) Seed Oil on Experimental Colitis in Rats

Zeynep Genc,Aysen Yarat,Tugba Tunali-Akbay,Goksel Sener,Sule Cetinel,Rabia Pisiriciler,Esin Caliskan-Ak,Ayhan Altıntas,Betul Demirci 한국식품영양과학회 2011 Journal of medicinal food Vol.14 No.12

This study investigated the effect of Urtica dioica, known as stinging nettle, seed oil (UDO) treatment on colonic tissue and blood parameters of trinitrobenzene sulfonic acid (TNBS)-induced colitis in rats. Experimental colitis was induced with 1mL of TNBS in 40% ethanol by intracolonic administration with a 8-cm-long cannula with rats under ether anesthesia, assigned to a colitis group and a colitis +UDO group. Rats in the control group were given saline at the same volume by intracolonic administration. UDO (2.5mL/kg) was given to the colitis +UDO group by oral administration throughout a 3-day interval, 5 minutes later than colitis induction. Saline (2.5 mL/kg) was given to the control and colitis groups at the same volume by oral administration. At the end of the experiment macroscopic lesions were scored, and the degree of oxidant damage was evaluated by colonic total protein, sialic acid, malondialdehyde (MDA), and glutathione levels, collagen content, tissue factor activity, and superoxide dismutase and myeloperoxidase activities. Colonic tissues were also examined by histological and cytological analysis. Pro-inflammatory cytokines (tumor necrosis factor-a, interleukin-1b, and interleukin-6), lactate dehydrogenase activity, and triglyceride and cholesterol levels were analyzed in blood samples. We found that UDO decreased levels of pro-inflammatory cytokines, lactate dehydrogenase, triglyceride, and cholesterol, which were increased in colitis. UDO administration ameliorated the TNBS-induced disturbances in colonic tissue except for MDA. In conclusion, UDO, through its anti-inflammatory and antioxidant actions, merits consideration as a potential agent in ameliorating colonic inflammation.

Medical and Dietary Therapy for Kidney Stone Prevention

Zeynep Gul,Manoj Monga 대한비뇨의학회 2014 Investigative and Clinical Urology Vol.55 No.12

The prevalence of kidney stone disease is increasing, and newer research is finding thatstones are associated with several serious morbidities. These facts suggest that emphasisneeds to be placed not only on stone treatment but also stone prevention. However, there is a relative dearth of information on dietary and medical therapiesto treat and avoid nephrolithiasis. In addition, studies have shown that there are manymisconceptions among both the general community and physicians about how stonesshould be managed. This article is meant to serve as a review of the current literatureon dietary and drug therapies for stone prevention.

Mathematics teacher quality: its distribution and relationship with student achievement in Turkey

Zeynep Ebrar Yetkiner Özel 서울대학교 교육연구소 2013 Asia Pacific Education Review Vol.14 No.2

A main purpose of the present study was to investigate the distribution of qualified mathematics teachers in relation to students’ socioeconomic status (SES), as measured by parental education, among Turkish middle schools. Further, relationships between mathematics teacher quality indicators and students’ mathematics achievement were explored. Data from the 2007 Trends in International Mathematics and Science Study were used. Relationships between mathematics teacher quality and students’ mathematics achievement were investigated using hierarchical linear modeling. The current study identified SES-related inequities in access to qualified mathematics teachers in Turkey. Low-SES students were more likely to be taught by mathematics teachers who had less than 3 years of experience or who did not hold a degree in mathematics or mathematics education. On the other hand, years of experience and a degree in mathematics or mathematics education were found to be substantially related to Turkish eighth-grade students’ mathematics achievement. Low-SES students’ mathematics teachers were also more likely to report a lack of confidence in their preparation to teach various mathematics contents.