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Article Citation - WoS: 28Citation - Scopus: 28Polycrystalline Diamond End Mill Cutting Edge Design To Improve Ductile-Mode Machining of Silicon(Elsevier Science inc, 2018) Oliaei, S. N. B.; Karpat, Y.Silicon is a commonly used material in optoelectronics and micro fluidics devices. Micro mechanical milling of silicon with polycrystalline diamond (PCD) tools has the potential to produce three-dimensional surfaces with good surface finish and an increased material removal rate. PCD micro end mill geometry is known to influence process outputs yet its effect has not been studied in detail. In this study, a PCD end mill with a hexagonal geometry has been considered, and its micro cutting geometry has been modified to have a parallelogram shape featuring a large negative rake angle on the bottom of the tool. The proposed micro geometry also reduces the contact area between the tool and the work material. The proposed geometry was fabricated using wire electric discharge machining (WEDM). Ductile-to-brittle transition conditions and areal surface roughness have been investigated as a function of tool geometry and feed during micro milling of silicon. A significant improvement in material removal rate and surface roughness has been obtained compared to a commercially available PCD end mill having hexagonal geometry with flat bottom. The results show that PCD micro end mill geometry significantly affects the process outputs.Article Citation - WoS: 18Citation - Scopus: 21Musculoskeletal Pain, Related Factors, and Posture Profiles Among Adolescents: a Cross-Sectional Study From Turkey(Elsevier Science inc, 2021) Ozdemir, Serpil; Gencbas, Dercan; Tosun, Betul; Bebis, Hatice; Sinan, OzlemPurpose: The aim of the study was to evaluate musculoskeletal pain due to mechanical reasons and related risk factors in adolescents and to define posture profiles of adolescents. Design: A cross-sectional study. Methods: The study was conducted with 2221 adolescents between February 2015 and May 2015. The questionnaire used to collect data consisted of three parts: (1) descriptive characteristics of the participants, (2) pain assessment of 14 parts of the body, and (3) Back Pain and Body Posture Evaluation Instrument (BackPEI). Results: The prevalence of low back pain among the participants was 73.3% (n = 1,343), while the prevalence of back pain was 68.4% (n = 1,254). The participants attributed their pain to their poor sitting postures at school (38.1%, n = 847) and carrying school backpacks (84.1%, n = 1,713). There was a statistically significant difference in the physical activities of adolescents and the BackPEI score (z = 4.40; p = .001). Posture factors of the BackPEI score increased while school desk comfort score increased (Spearman's rho = 0.148; p = .001), but it decreased while the school grades of the adolescents increased (Spearman's rho [rho] = -0.161; p = .001). Conclusions: According to this study, body posture was related to musculoskeletal pain and was correlated with physical activities, school desk comfort, and school grades of the adolescents. It is suggested that correct posture and ergonomic positions should be taught to adolescents when using computers, carrying school backpacks, and sitting in school chairs to prevent musculoskeletal pain. (C) 2020 American Society for Pain Management Nursing. Published by Elsevier Inc. All rights reserved.Article Citation - WoS: 59Citation - Scopus: 71Effects of Reflexology and Progressive Muscle Relaxation on Pain, Fatigue, and Quality of Life During Chemotherapy in Gynecologic Cancer Patients(Elsevier Science inc, 2019) Dikmen, Hacer Alan; Terzioglu, FusunPurpose: Our aim was to investigate the effect of reflexology and progressive muscle relaxation (PMR) exercises on pain, fatigue, and quality of life (QoL) of gynecologic cancer patients during chemotherapy. Methods: Eighty participants were randomly assigned to one of four groups: reflexology, progressive muscle relaxation (PMR) exercises, both (reflexology + PMR), or a control group. Data were collected with a general data collection form, Brief Pain and Fatigue inventories, and Multidimensional Quality-of-Life Scale-Cancer. Results: In reflexology and reflexology + PMR groups, a significant decrease in pain severity and fatigue and an increase in QoL were found (p < .05). In the PMR alone group, pain severity and fatigue decreased significantly (p < .05), but there was no significant change identified in QOL (p > .05). Conclusions: Reflexology and PMR exercises given to gynecologic cancer patients during chemotherapy were found to decrease pain and fatigue and increase QoL. (C) 2019 American Society for Pain Management Nursing. Published by Elsevier Inc. All rights reserved.Article Citation - WoS: 9Citation - Scopus: 9Ir-Spectroscopic Characterization of an Elongated Ompg Mutant(Elsevier Science inc, 2015) Korkmaz, Filiz; van Pee, Katharina; Yildiz, OezkanOmpG is a nonselective, pH dependent outer membrane protein from Escherichia coli. It consists of 281 residues, forming a 14-stranded beta-sheet structure. In this study, OmpG is extended by 38 amino acids to produce a 16-stranded beta-barrel (OmpG-16S). The resulting protein is investigated by IR-spectroscopy. The secondary structure, pH-dependent opening/closing mechanism, buffer accessibility and thermal stability of OmpG-16S are compared to OmpG-WT. The results show that OmpG-16S is responsive to pH change as indicated by the Amide I band shift upon a switch from acidic to neutral pH. This spectral shift is consistent with that observed in OmpG-WT, which confirms the existence of structural differences consistent with the presence of the open or closed state. Secondary structure analysis after curve-fitting of Amide I band revealed that the additional residues do not fold into beta-sheet; rather they are in the form of turns and unordered structure. In thermal stability experiments, OmpG-16S is found to be as stable as OmpG-WT. Additionally, H/D exchange experiments showed no difference in the exchange rate of OmpG-16S between the acidic and alkaline pH, suggesting that the loop L6 is no longer sufficient to block the pore entrance at acidic pH. (C) 2015 Elsevier Inc. All rights reserved.Article Citation - WoS: 14Citation - Scopus: 15Are Tourists Afraid of the Unknown? Examining the Role of Travel Constraints and Tourist Xenophobia With Symmetric and Asymmetric Perspectives(Elsevier Science inc, 2023) Dedeoglu, Bekir Bora; Bogan, Erhan; Kucukergin, Kemal Gurkan; Birinci, Muhammet CenkThis study aims to investigate the role of tourists' xenophobia and travel constraints in terms of affecting image and choice of a given destination within the framework of generations. Although many existing studies have examined destination preference from different perspectives, the lack of analyses with specific references to generations and tourist xenophobia is striking. Therefore, it is believed that studying these structures on the basis of the complexity perspective paves the way for providing specific suggestions to researchers and destination management organizations. To this end and specifically, this study endeavors to reveal the importance of ele-ments influencing the intention of potential Turkish tourists to visit France as a target destination using sym-metric and asymmetric models.Article Citation - WoS: 6Citation - Scopus: 8Preterm Birth and Maternal Sensitivity: Findings From a Non-Western Country(Elsevier Science inc, 2020) Akkus, P. Zengin; Saygan, B. Bahtiyar; Bahadur, E. Ilter; Ozdemir, G.; Ozmert, E. N.Introduction: Although there are several studies on maternal sensitivity of preterm-born children conducted in Western countries, the factors affecting the sensitivity of mothers of preterm infants have not been investigated outside the Western context. Objectives: This study aimed to compare maternal sensitivity of preterm children at 18 months of corrected age with their healthy term-born peers and explore the factors associated with maternal sensitivity in a middle-income non-Western country. Moreover, the associations of maternal sensitivity with socio-demographic factors, maternal depression, and social-emotional competency and behavior problems of infants were investigated. Methods: In total, 70 (40 preterm-born and 30 term-born) mother-child dyads participated in this study. An observation-based measurement tool, Maternal Sensitivity Scale, was used to assess maternal sensitivity. Social-emotional competency and behavior problems of infants were evaluated via The Turkish version of the Brief Infant-Toddler Social Emotional Assessment. Maternal depressive symptoms were assessed via the Beck Depression Inventory. In addition, a demographic information form was filled out by the mothers. Results: Maternal sensitivity scores of preterm infants were significantly lower compared to term infants. Depressive symptoms scores and employment status of mothers, socio-economic status (SES), gestational age, breastfeeding duration, and behavior problems of children were the factors related to maternal sensitivity scores. In hierarchical regression analysis, SES and gestational age were the strongest predictors of maternal sensitivity. After controlling SES and gestational age, maternal depressive symptoms scores negatively predicted maternal sensitivity scores. Conclusion: This study pointed out the factors associated with the maternal sensitivity of preterm infants outside the Western context. Interventions to improve sensitive parenting behaviors of preterm infants are needed, especially in socio-economically disadvantaged groups.Article Citation - WoS: 34Social Jetlag Is Associated With the Frequency of Consumption of Sugar-Sweetened Beverages and a High Bmi Percentile in Adolescents: Results of the Cross-Sectional Family Life, Activity, Sun, Health, and Eating (flashe) Study(Elsevier Science inc, 2021) Cetiner, Ozlem; Yildirim, Gonca; Kalyoncu, Zeynep BegumBackground Social jetlag (SJL) occurs in adolescents due to misalignment of the bio-logical and social clocks, so that most teens wake up earlier than their biological clocks on weekdays and delay bedtime and wake up time on weekends. This shift in sleep timing among adolescents is associated with an adverse endocrine and behavioral risk profile, in addition to increased food consumption and increased body mass index (BMI). Objective The aim of this study was to determine the association between SJL, and the frequency of consumption of multiple food and beverage groups and BMI percentile in adolescents. Design Publicly available data from the cross-sectional Family Life, Activity, Sun, Health, and Eating (FLASHE) study were analyzed. Participants Participants from the FLASHE study were recruited from all regions of the United States between April and October 2014. Among the 1,581 adolescents aged 12 through 17 years in the original study, 1,556 with complete sleep data were analyzed. Main outcome measures The difference between the frequency of dietary consump-tion according to the Dietary Screener Questionnaire and BMI percentile was assessed in adolescents grouped according to SJL, as follows: no SJL: less than 1-hour difference; mild SJL: 1-to 2-hour difference; and severe SJL: more than 2-hour difference. Statistical analyses performed Differences in the frequency of food consumption were analyzed using the Kruskal-Wallis test. Secondary outcomes were analyzed using logistic regression models. Results Daily consumption frequency of sugar-sweetened beverages and fruits and vegetables differed among the 3 groups. Likewise, the BMI percentile differed among the 3 groups and was highest in the severe SJL group. Those in the severe SJL group had a 1.84-fold higher probability of having overweight or obesity (95% CI 1.83 to 1.84) than those in the no SJL group. Conclusions Severe SJL is associated with a higher frequency of sugar-sweetened beverage consumption and higher odds of having overweight or obesity compared with no SJL in adolescents. J Acad Nutr Diet. 2021;121(9):1721-1731.Article Citation - WoS: 3Citation - Scopus: 6Outcomes of Pain Management Among Postoperative Patients: a Cross-Sectional Study(Elsevier Science inc, 2024) Akire, Sandra Chirota; Bayraktar, NurhanPurpose: Postoperative pain management has always been a significant challenge for both hospital staff and surgical patients. Determination of pain management outcomes among surgically treated patients may help develop pain management strategies, improve health services that would yield better outcomes, and increase patient satisfaction. This study aimed to assess the outcomes of pain management among postoperative patients. Design: The study was a descriptive cross-sectional study. Methods: The research was performed on postoperative patients at two university hospitals in North Cyprus from July to September 2019. The study sample consisted of 90 patients from both hospitals. The Turkish Version of the revised American Pain Society Patient Outcome Questionnaire (APS-POQ-R-TR) was used for data collection. The Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) checklist was used to report the present study. Findings: This study showed that the overall mean for pain severity and the worst pain experienced by patients after 24 hours was slightly higher than medium. Examination of interference of the pain with functions demonstrated that patients experienced problems with physical activities and sleeping. The most experienced side effects were nausea and drowsiness, and the most common emotions were anxiety and helplessness during the postsurgery period. The satisfaction rate of the patients with postoperative pain management was relatively high. Conclusions: A holistic approach with evidence-based practices is crucial for adequate postoperative pain management. The recommendations include the development of individual pain outcome strategies to improve overall satisfaction with pain management among postoperative patients. (c) 2024 American Society of PeriAnesthesia Nurses. Published by Elsevier Inc. All rights reserved.Article Citation - WoS: 29Citation - Scopus: 33Experimental Investigation of Surface Roughness Effects on the Flow Boiling of R134a in Microchannels(Elsevier Science inc, 2016) Jafari, Rahim; Okutucu-Ozyurt, Tuba; Unver, Hakki Ozgur; Bayer, OzgurThis study experimentally investigates the effect of surface roughness on the hydrodynamic and thermal performance of microchannel evaporators. Three micro-evaporators of the same dimensions and different surface roughness have been fabricated by micro-WEDM. Each micro-evaporator consists of forty rectangular microchannels of 700 mu m height, 250 mu m width, and 19 mm length. A microscale vapor compression refrigeration cycle has been constructed to carry out the experiments. R134a is used as the refrigerant. Heat transfer coefficient, pressure drop and COP results are presented at variously imposed heat fluxes, and at mass fluxes of 85 and 200 kg/(m(2)s). The results demonstrate up to 45% enhancement in the two-phase heat transfer coefficient at low to moderate heat flux values as the surface roughness increases. Considering the surface roughness effect of the microchannel walls, a new correlation is developed to predict the heat transfer coefficient of R134a boiling in microchannels. (C) 2016 Elsevier Inc. All rights reserved.Article Citation - WoS: 11Citation - Scopus: 11Modified Criteria for Global Robust Stability of Interval Delayed Neural Networks(Elsevier Science inc, 2009) Singh, VimalTwo simple criteria for global robust stability of Hopfield-type interval neural networks with delay are presented. The criteria turn out to be modified versions of an earlier criterion due to Cao, Huang, and Qu. Examples show the effectiveness of the modified criteria. Numerical simulations are carried out to confirm the applicability of the modified criteria. (C) 2009 Elsevier Inc. All rights reserved.
