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Infill density used in additive manufacturing incorporates a structural response change in the structure. Infill pattern creates a microstructure that affects the mechanical performance as well. Whenever the length ratio of microstructure to geometry converges to one, metamaterials emerge and the strain-gradient theory is an adequate model to predict metamaterials response. All metamaterial parameters are determined by an asymptotic homogenization, and we investigate the effects of infill density and pattern on these parameters. In order to illuminate the role of infill characteristics on the strain-gradient parameters, an in-depth numerical investigation is presented for one, widely used case in three-dimensional (3D) printers, rectangular grid.

Purpose To document time analysis of detailed workflow steps for the online adaptive magnetic resonance–guided radiation therapy treatments (MRgRT) with the ViewRay MRIdian system and to identify the barriers to and solutions for shorter treatment times. Methods and Materials A total of 154 patients were treated with the ViewRay MRIdian system between September 2018 and October 2019. The time process of MRgRT workflow steps of 962 fractions for 166 treatment sites was analyzed in terms of patient and online adaptive treatment (ART) characteristics. Results Overall, 774 of 962 fractions were treated with online ART, and 83.2% of adaptive fractions were completed in less than 60 minutes. Sixty-three percent, 50.3%, and 4.2% of fractions were completed in less than 50 minutes, 45 minutes, and 30 minutes, respectively. Eight-point-three percent and 3% of fractions were completed in more than 70 minutes and 80 minutes, respectively. The median time (tmed) for ART workflow steps were as follows: (1) setup tmed: 5.0 minutes, (2) low-resolution scanning tmed: 1 minute, (3) high-resolution scanning tmed: 3 minutes, (4) online contouring tmed: 9 minutes, (5) reoptimization with online quality assurance tmed: 5 minutes, (6) real targeting tmed: 3 minutes, (7) beam delivery with gating tmed: 17 minutes, and (8) net total treatment time tmed: 45 minutes. The shortest and longest tmean rates of net total treatment time were 41.59 minutes and 64.43 minutes for upper-lung-lobe-located thoracic tumors and ultracentrally located thoracic tumors, respectively. Conclusions To our knowledge, this is the first broad treatment-time analysis for online ART in the literature. Although treatment times are long due to human- and technology-related limitations, benefits offered by MRgRT might be clinically important. In the future, implementation of artificial intelligence segmentation, an increase in dose rate, and faster multileaf collimator and gantry speeds may lead to achieving shorter MRgRT treatments.

Background Stereotactic ablative radiotherapy (SABR) is effective for thoracic cancer and metastases; however, adverse effects are greater for central tumors. We evaluated factors affecting outcomes and toxicities after SABR for patients with primary lung and oligometastatic tumors. Patients and methods We retrospectively identified consecutive patients with centrally located lung tumors that were treated at our hospital from 2009-2016. The effects of patient, disease, and treatment-related parameters on local control (LC), overall survival (OS), and toxicity-free survival (TFS) were evaluated with multivariate analyses. Results Among 65 consecutive patients identified with 70 centrally located tumors, 20 tumors (28%) were reirradiated. Median (range) total dose for all tumors was 55 (30–60) Gy in 5 (3–10) fractions. Radiographic complete response was obtained in 43 lesions (61%). None of the analyzed factors were correlated with complete response. After a median follow-up of 57 (95% CI, 48–65) months, 10 tumors (14%) relapsed and 37 patients (57%) died; the actuarial 2- and 5-year OS rates were 52% and 28%, respectively. Median OS was significantly lower in patients with grade 3 or higher toxicity vs. lower toxicity (5 vs. 39 months; P < 0.001). Among 17 severe toxicities, 5 were grade 5, and 3 of them were reirradiated to the same field. Grade 3 to 5 TFS was lower with vs. without reirradiation (2-year TFS, 63% vs. 96%; P = 0.02). Conclusions Our study showed that modern SABR is effective for central lung tumors, and toxicities are acceptable. SABR for reirradiated central lung lesions and possibly for lesions abutting the tracheobronchial tree may result in higher risk of serious toxicities.

Social commerce has become a hot topic since the beginning of Web 2.0 era; however, relevant research is scarce in emerging economies. This study aims to fill this research gap and answer the main research question of ?what type of relevant personality traits and shopping motivations affect social commerce adoption intentions?. The research model was developed upon personality traits (openness to experience, need for uniqueness and buying impulsiveness) that are deemed to be relevant to online shopping and social media use. An online questionnaire was conducted on social media users. A total of 269 valid questionnaires were analyzed via structural equation modeling to test for the proposed relationships, majority of which emerged as non-linear. The findings highlight the significance of socialization motives in addition to utilitarian and hedonic shopping motives on social commerce adoption intentions. Openness to experience emerged as a significant trait that has an indirect effect on social commerce adoption intentions. Age and education materialized as significant demographics influencing shopping motivations in a social commerce setting.

Changes in consumer behavior enabled by social networking technologies is leading to a transformation in e-commerce. Consumers' use of social media sites and relevant technologies for different aspects of shopping has become an issue of utmost concern to retailers and related businesses. Adopting a uses and gratifications theory (UGT) perspective, the article aims to demonstrate motives of users utilizing social media in their purchase decisions. Drawing from digital marketing and e-commerce literature, relevant uses and gratifications for social commerce (s-commerce) were chosen as information access, escape, entertainment, passing time, cool and new trends, and socialization. The proposed model was analyzed and tested via OLS regression and ANOVA analysis using the data collected from a survey study on 361 subjects in Turkey. Information access, relaxing entertainment, and socialization motives emerged as significant antecedents of s-commerce intentions. No significant effect of demographics on social commerce intentions were observed in the analysis.

Aim: The prevalence of atrial fibrillation (AF) in patients with myocardial infarction (MI) ranges widely and has been reported to be as high as 21%. However, the demographic, clinical, and angiographic characteristics of AF patients with de novo MI is unclear. The aim of this study was to investigate the prevalence of patients presenting with de novo MI with AF. Methods: The study was performed as a sub-study of the MINOCA-TR (Myocardial Infarction with Non-obstructive Coronary Arteries in Turkish Population) Registry, a multicenter, cross-sectional, observational, all-comer registry. MI patients without a known history of stable coronary artery disease and/or prior coronary revascularization were enrolled in the study. Patients were divided into AF and Non-AF groups according to their presenting cardiac rhythm. Results: A total of 1793 patients were screened and 1626 were included in the study. Mean age was 61.5 (12.5) years. 70.7% of patients were men. Prevalence of AF was 3.1% (51 patients). AF patients were older [73.4 (9.4) vs. 61.0 (12.4) years, p

WOS: 000413325200001 Gamification has become an influential term in diverse fields ranging from education to systems development and marketing. The recent intensifying emphasis is attributable to enabling technologies and successful practical applications used for changing attitudes and increasing engagement. However, relevant academic studies are not wide-spread and this study aims to address this vital research gap. This study is structured to understand the factors affecting intention to use gamified systems and test whether they are affected by gender or age. An online survey study was conducted on a web-based gamified system (EmpireAvenue.com) and following a detailed screening process, a total of 168 fully complete questionnaires were attained. The theoretical model employed was developed upon technology acceptance model (TAM) and modified to incorporate an intrinsic motivation element, namely the "perceived enjoyment" construct. According to the findings, age and gender moderate the relationships between usefulness, ease of use, perceived enjoyment and intention to use the gamified system.

Social media sites are becoming more popular throughout the world. These sites are adopting advertisement supported business models to generate revenues and become profitable. Advertisement supported models are the preferred choice for these site with regards to the belief that users are not willing to pay money to use these ever free sites. In this study this belief was questioned and Facebook, the most popular of social media sites was chosen as the setting of the study. The attitudes towards social media advertisements and their antecedents were measured and their potential effects on users’ willingness to pay for not seeing ads were tested. A questionnaire was developed using well-cited and tested scales from the relevant literature and it was implemented over Internet to Facebook users. 281 out of 327 collected questionnaires were used in the analysis following a screening process. The analysis was carried out using structural equation modelling. The findings indicate that attitudes and its antecedents affect th intentions to pay for not seeing ads negatively.

WOS: 000458309000003 PubMed ID: 30632271 Purpose The electron energy characteristics of mobile intraoperative radiotherapy (IORT) accelerator LIAC((R)) differ from commonly used linear accelerators, thus some of the frequently used detectors can give less accurate results. The aim of this study is to evaluate the output factors (OFs) of several ionization chambers (IC) and solid state detectors (SS) for electron beam energies generated by LIAC((R)) and compare with the output factor of Monte Carlo model (MC) in order to determine the adequate detectors for LIAC((R)). Methods The OFs were measured for 6, 8, 10, and 12 MeV electron energies with PTW 23343 Markus, PTW 34045 Advanced Markus, PTW 34001 Roos, IBA PPC05, IBA PPC40, IBA NACP-02, PTW 31010 Semiflex, PTW 31021 Semiflex 3D, PTW 31014 Pinpoint, PTW 60017 Diode E, PTW 60018 Diode SRS, SNC Diode EDGE, and PTW 60019 micro Diamond detectors. Ion recombination factors (k(sat)) of IC were measured for all applicator sizes and OFs were corrected according to k(sat). The measured OFs were compared with Monte Carlo output factors (OFMC). Results The measured OFs of IBA PPC05, PTW Advanced Markus, PTW Pinpoint, PTW microDiamond, and PTW Diode E detectors are in good agreement with OFMC. The maximum deviations of IBA PPC05 OFs to OFMC are -1.6%, +1.5%, +1.5%, and +2.0%; for PTW Advanced Markus +1.0%, +1.5%, +2.0%, and +2.0%; for PTW Pinpoint +2.0%, +1.6%, +4.0%, and +2.0%; for PTW microDiamond -1.6%, +2%, +1.1%, and +1.0%; and for PTW Diode E -+1.7%, +1.7%, +1.3%, and +2.5% for 6, 8, 10, and 12 MeV, respectively. PTW Roos, PTW Markus, IBA PPC40, PTW Semiflex, PTW Semiflex 3D, SNC Diode Edge measured OFs with a maximum deviation of +5.6%, +4.5%, +5.6%, +8.1%, +4.8%, and +9.6% with respect to OFMC, while PTW Diode SRS and IBA NACP-02 were the least accurate (with highest deviations -37.1% and -18.0%, respectively). Conclusion The OFs results of solid state detectors PTW microDiamond and PTW Diode E as well as the ICs with small electrode spacing distance such as IBA PPC05, PTW Advanced Markus and PTW Pinpoint are in excellent agreement with OFMC. The measurements of the other detectors evaluated in this study are less accurate, thus they should be used with caution. Particularly, PTW Diode SRS and IBA NACP-02 are not suitable and their use should be avoided in relative dosimetry measurements under high dose per pulsed (DPP) electron beams.

Objectives Improved soft-tissue visualization, afforded by magnetic resonance imaging integrated into a radiation therapy linear accelerator-based radiation delivery system (MR-linac) promises improved image-guidance. The availability of MR-imaging can facilitate on-table adaptive radiation planning and enable real-time intra-fraction imaging with beam gating without additional exposure to radiation. However, the novel use of magnetic resonance-guided radiation therapy (MRgRT) in the field of radiation oncology also potentially poses challenges for routine clinical implementation. Herein the early experience of a single institution, implementing the first MRgRT system in the country is reported. We aim to describe the workflow and to characterize the clinical utility and feasibility of routine use of an MR-linac system. Methods The ViewRay MRIdian MR-linac system consists of a split-magnet 0.35 T MR-imaging scanner with a double focused multi-leaf collimator (MLC) equipped 6MV linear accelerator. Unique to the system are the control console integrated on-table adaptive radiation therapy (oART) planning capabilities as well as automated beam gating based on real-time intra-fraction MR imaging. From the first day of clinical implementation, oART was performed according to physicians’ discretion when medically indicated. All fractions were delivered under real-time imaging with soft tissue-based automated beam gating with individualized gating boundary settings. Patients actively assisted in breath-hold beam gating with the help of custom designed prismatic glasses allowing sight of a computer monitor mounted on the back wall just behind the MRI system bore. Patient demographics and treatment experience, indications for MRgRT including diagnosis and disease site, radiation dose prescribed and fractionation scheme, utilization of oART, respiratory gating settings, as well as duration of each treatment phase were analyzed. Results Between September 2018 and May 2019, 72 patients with 84 tumor sites were treated with MRgRT in 500 total fractions. Median patient age was 66 years (range: 28-83 years). Among 84 tumor sites, the most frequently treated regions were upper abdominal and pelvic (n = 36, 43% and n = 29, 34%, respectively). The most common diagnosis was prostate cancer, with 14 patients treated. In 69 patients (93.2%) oART was used at least once during a treatment course. Twenty-nine targets (43.1%) with significant breathing-related motion were treated in breath-hold with patient visual feedback. Median prescribed dose was 36.25 Gy (range: 24-70 Gy) in median five fractions (range: 3-28 fractions). A gating boundary of 3 mm around a gating region of interest (gROI) was most commonly used (range: 3-5 mm) with 95% of the gROI (range: 93-97%) required to be within the gating boundary for the beam to automatically engage. Mean total treatment time was 47 min (range: 21-125 min) and mean beam-on time was 16.7 min (range: 6-62 min). Conclusions MRgRT afforded by an MR-linac system has been successfully implemented into routine clinical use at our institution as the first system of its kind in Turkey. While the overall number of patients treated and fractions delivered is still limited, we have demonstrated the feasibility of both on-table adaptive radiation therapy as well as automated real-time beam gating on a daily basis in acceptable time schedules.

Background Despite the benefits offered by an abundance of health applications promoted on app marketplaces (e.g., Google Play Store), the wide adoption of mobile health and e-health apps is yet to come. Objective This study aims to investigate the current landscape of smartphone apps that focus on improving and sustaining health and wellbeing. Understanding the categories that popular apps focus on and the relevant features provided to users, which lead to higher user scores and downloads will offer insights to enable higher adoption in the general populace. This study on 1,000 mobile health applications aims to shed light on the reasons why particular apps are liked and adopted while many are not. Methods User-generated data (i.e. review scores) and company-generated data (i.e. app descriptions) were collected from app marketplaces and manually coded and categorized by two researchers. For analysis, Artificial Neural Networks, Random Forest and Naïve Bayes Artificial Intelligence algorithms were used. Results The analysis led to features that attracted more download behavior and higher user scores. The findings suggest that apps that mention a privacy policy or provide videos in description lead to higher user scores, whereas free apps with in-app purchase possibilities, social networking and sharing features and feedback mechanisms lead to higher number of downloads. Moreover, differences in user scores and the total number of downloads are detected in distinct subcategories of mobile health apps. Conclusion This study contributes to the current knowledge of m-health application use by reviewing mobile health applications using content analysis and machine learning algorithms. The content analysis adds significant value by providing classification, keywords and factors that influence download behavior and user scores in a m-health context.

Brain metastases are commonly seen complications in non-small cell lung cancer (NSCLC) patients. The incidence of brain metastases is increasing as a result of more effective systemic targeted therapies with prolonged survival. The prognosis is usually poor, and up to six months of median survivals were reported with different therapeutic options. Here, we present an NSCLC case with multiple brain metastases treated with radiosurgery and systemic erlotinib therapy with prolonged survival. The use of tyrosine kinase inhibitors (TKI) in conjunction with either stereotactic radiosurgery or whole brain radiotherapy is not well established in terms of efficiency and toxicity. This reported case had an excellent response with a tolerable toxicity profile from the combination of either therapies.

Buçalışmanın amacı, Türkiye’de faaliyet gösteren turizm tesislerinin sosyalmedyadaki faaliyetlerinin etkinliğini Facebook özelinde ölçmek ve paylaşımlarınetkinliğinin artırılabilmesi için öneriler ortaya koymaktır. Bu doğrultudagerçekleştirilen araştırmada turizm tesislerinin Facebook hesabının kullanımdurumu ve sıklığı ölçülmüş, paylaşılan içerik tipinin, takipçilerin etkileşimiüzerindeki olası etkilerinin belirlenmesi hedeflenmiştir. Araştırmanın amacıkapsamında Türkiye’de faaliyet gösteren tüm 5 yıldızlı turizm tesisleriaraştırmaya dahil edilmiştir. Tesislerin belirlenmesinde T.C. Turizm ve KültürBakanlığı’ndan elde edilen turizm işletmesi belgeli kuruluşlar listesi esasalınmıştır. Listede yer alan toplam 612 turizm tesisinden aktif olarak Facebooksayfasını kullanan 441 adedi Facebook hesapları üzerinden veri toplanmıştır. Sözkonusu 441 adet 5 yıldızlı otelin 1 ay boyunca yaptıkları paylaşımlar araştırmayaesas alınmış ve bir içerik formu yardımıyla 2,012 paylaşımla ilgili veriye ulaşılmıştır.Paylaşım, içerik kategorisi, içerik dikkat çekiciliği, sunulan interaktiflik veelde edilen takipçi etkileşimi (beğeni, yorum sayısı ve yorumun niteliği)hakkında bilgi toplanmıştır. Elde edilen veriler filtrelenerek analiz içinuygun olan 1847 paylaşım SPSS programı yardımıyla analiz edilmiştir., The aim ofthis study is to measure the effectiveness of social media activities oftourism establishments operating in Turkey. Suggestions to improve theefficiency of these mediums are also aimed to be arrived at. In this study, Facebookaccount use behavior of tourism establishments’ was measured and possibleeffects of type and content of posts on followers' interaction were discussed.All 5-star tourism facilities operating in Turkey were included in the scope ofthe study. These institutions were obtained from Ministry of Tourism andCulture’s public information database that includes all certified tourismestablishment in Turkey. The Facebook accounts of the 441 hotels that actively useFacebook from a total of 612 hotels were examined. Their posts on Facebook for1 month were taken as basis of the data collection. Information on Facebookposts of hotels were collected using a traditional content analysis form. Atotal of 2,012 posts were collected that provide information on post contentcategory, content type, interactivity offered, follower interaction (likes andcomments). The obtained data were filtered down to 1847 posts, which were thenanalyzed in SPSS application.

Aim CyberKnife® is a robotic stereotactic radiotherapy system. The aim of this study is to evaluate the effectiveness and the safety of CyberKnife® on treating head and neck paragangliomas and to report our results. Methods Between March 2009 and June 2014, 12 patients with head and neck paragangliomas have been referred to our clinic: in three cases had jugular paragangliomas, five cases had carotid body paragangliomas and three cases had tympanic paragangliomas. One patient had bilateral neck paragangliomas (right neck; carotid body paraganglioma, left neck; jugular pargangliomas). All of them received fractionated stereotactic radiotherapy with CyberKnife® up to a total median dose of 24 Gy (reference isodose 67–90%). The median tumor volume was 35.5 cc (range, 5.3—113.8 cc). The median follow up was 30 months (range, 0–66 months). Local tumor control was assessed according to RECIST criteria on follow-up imaging studies. Results There were no acute or late toxicity related with stereotactic radiotherapy after treatment. No local tumor progression was observed on magnetic resonance imaging and none of our patients showed progressive clinical status. Seven tumors shrinked in size (54%). Five tumors (46%) had stable size during follow up. Local control rate was 100%. Conclusion Stereotactic radiotherapy is a good alternative to surgery for the treatment of head and neck paragangliomas coming up with a clear benefit of acute and late side effects. CyberKnife® seems to be a safe and efficient system treating head and neck paragangliomas.

Background: Although the early re-polarization pattern known as a benign condition, it can result in idiopathic ventricular fibrillation and sudden cardiac death. In this study, we aimed to evaluate the prevalence of early repolarization pattern in young healthy men. Methods and Patients: Four hundred fourteen young healthy man were enrolled in the study. PR intervals, QRS durations, QT intervals and corrected QT durations were measured from electrocardiographic records. Early re-polarization pattern was defined as if an elevation J-point was greater than 0,1 mV according to the isoelectrical point. Results: The prevalence of early repolarization pattern was 23,2 % (n=96). Of these, we found early re-polarization pattern in inferior, lateral and inferolateral leads with 14,7%, 2,2% and 6,3% respectively. There was a significant relation between heart rate and elevation of J point. Conclusion: The prevalence of early repolarization pattern in young healthy men from Turkey was similar with the previously reported rates from different white populations.

Luxury consumption has an increasing trend despite the recent global economic crisis. Luxury tourism and luxury hospitality are among the leading categories that drive luxury consumption. The definition of luxury as well the luxury tourism destinations is not a constant and may vary from an individual to another. The destination to be travelled is one of the important criteria determining luxury perceptions. In this study, consumers’ luxury destination perceptions are sought to be determined in order to set a foundation to further develop upon in luxury destination studies that are in scarce supply in Turkey. This study area offers Turkey, which targets to achieve higher levels of tourism revenues in the next decade an important opportunity to realize this goal. The conspicuous luxury destinations and non-conspicuous destinations are determined by a two-stage survey study. The three conspicuous destinations appeared as Bodrum, Antalya and Çeşme as the outcome of the analysis carried out.

Aims and background We compared conformal, intensity-modulated radiotherapy (IMRT) and intensity-modulated arc therapy (IMAT) in early stage glottic cancer in terms of dosimetric features as target coverage, dose to the organs at risk and total treatment time. Methods and materials Five consecutive T1 glottic squamous cell carcinoma patients were selected for the study. Three-dimensional conformal radiotherapy (3D-CRT), 3-field or 5-field intensity-modulated radiotherapy (3F-IMRT and 5F-IMRT), or IMAT, which was in 2 different forms – a regular IMAT (R-IMAT) and an alternative IMAT (A-IMAT) with an unirradiated section, was planned for each patient. The prescribed dose was 63 Gy in 28 fractions. The minimum dose for 95% of the clinical target volume (D95), maximum dose point at clinical target volume (Dmax), total monitor units, left and right carotid artery doses (V35 and V50 – percentage of volume receiving 35 Gy and 50 Gy), and total treatment time were calculated for each plan. Results Median D95 values in the 5 plans studied with each technique ranged between 63 and 63.3 Gy (P = NS). Median Dmax values for each technique ranged between 65.4 and 70.8 Gy. The number of hot spots with IMRT and IMAT was significantly higher than with 3D-CRT plans. Conformal radiotherapy plans median V35 (93.6%) and V50 (76.6–83.3%) values for carotid arteries were significantly higher than with IMRT and IMAT (2.9%-11.4% and 0.0%). Average treatment times for 3D-CRT, 3F-IMRT, 5F-IMRT, R-IMAT and A-IMAT techniques were calculated as 64, 119, 147, 39 and 32 seconds, respectively. Conclusions IMAT has significantly decreased the treatment time compared to IMRT and 3D-CRT with acceptable homogeneous clinical target volume coverage and low carotid dose.

This study aims to understand the factors contributing to consumer attitude development towards and intention to use mobile payment systems. One of major mobile network operators’ mobile wallet application in Turkey was used as a proxy of the mobile payment systems. Survey methodology is used to collect data from subscribers by stratified random sampling among two distinct groups (users and nonusers). A total of 1395 questionnaires were collected from subscribers and analyzed using partial least squares structural equation modeling. The findings highlight the importance of ease of use and usefulness in attitude development. On the other hand, security concerns were found to have low level of effects on attitudes and use intentions. Effect of social influence was found to be insignificant among the users. There were differences between users’ and non-users’ perceptions and beliefs indicated by significant differences in the majority of the constructs employed in the study.

The study was conducted to elucidate the possibility that a shift in color preferences of adults of the apple blossom beetle, Epicometis hirta, occurs sometime after the end of over-wintering and the onset blooming of Prunus spp. trees and between the termination of blooming and the death of the adults. Such information is needed to choose the best color of the traps used for the detection, monitoring and suppression of this major pest. In a randomized complete block experiment with 9 replicates at 3 different cherry orchard sites in Turkey, blocks of 11 differently colored traps each ere operated and serviced daily in cherry orchards from the end of hibernation of E. hirta the adults disappeared at the end of the season. The numbers of adult beetles captured in each of the 11 differently colored traps in each block were recorded daily. According to ANOVA and the Tukey's test (P < 0.01), significantly the largest numbers of E. hirta were sampled by floral white-colored traps in both the pre-bloom...

In this work, a new dynamical on-line learning algorithm for robust model-free neuro-adaptive control of a class of nonlinear systems with uncertain dynamics is proposed and experimentally tested in order to evaluate its performance and practical feasibility in industrial settings. The control application studied is the trajectory tracking control task for the first three joints of an open architecture articulated robot manipulator. The control scheme makes use of variable structure systems theory and the feedback-error-learning concept. An inner sliding motion is established in terms of the neurocontroller parameters, aiming to lead the error in its control signal towards zero. The outer sliding motion bears on the system under control, the state tracking error vector of which is simultaneously driven towards the origin of the phase space. The existing relation between the two sliding motions is shown. Experimental results illustrate that the proposed neural-network-based controller possesses a remarkable learning capability to control complex dynamical systems, virtually without requiring a priori knowledge of the plant dynamics and laborious start-up procedures. Copyright © 2007 John Wiley & Sons, Ltd.

This study aims to find empirical evidence linking consumer based brand equity (CBBE) with financial performance of firms. Aaker’s CBBE approach is adopted and this equity is measured using a questionnaire developed from scales in existing literature. Differing from the extant literature, this study relates CBBE and firms’ performance by taking a direct approach in measuring financial performance by utilizing independently audited financial statements. A face-to-face survey study encompassing 28 companies from a variety of consumer goods industries was carried out in Turkey arriving at 505 valid responses. Firms’ financial performance was assessed using ten different performance indicators derived from financial statements submitted to Istanbul Stock Exchange. Following an exploratory factor analysis to reveal CBBE dimensions, a multiple regression analysis was carried out to test potential effects of CBBE factors on financial performance indicators. As an outcome of the analysis it has been seen that the components of CBBE positively affect most of the financial performance indicators to varying extents. Perceived quality dimension appears to be the major driver of financial performance followed by the composite factor encompassing brand awareness and brand association components.

Kullanımları dünya genelinde yaygınlaşan sosyal medya siteleri ciro yaratarak karlı birer işletme haline gelebilmek için günümüzde reklam destekli iş modelleri kullanmaktadır. Kullanıcıların ücretsiz olarak kullanmaya alıştığı bu platformlara erişim için ücret ödemek istemeyecekleri varsayımıyla reklam destekli modeller tercih edilmektedir. Bu çalışma içerisinde sosyal medya sitelerinin en yaygın kullanılanı olan Facebook üzerinde gösterilen reklamlara kullanıcıların tutumları ölçümlenmiş ve bu tutum ve tutumu oluşturan faktörlerin Facebook reklamlarını görmemek için para ödemeye etkisi test edilmiştir. Ödeme eğiliminde olan ve olmayan kullanıcılar arasında farklılar irdelenmiştir. Literatürde kabul görmüş ölçekler yardımıyla hazırlanan anket formu İnternet üzerinden Facebook kullanıcılarına dağıtılmış, elde edilen 327 soru formu bir ön-analiz sürecinden geçirilerek düşük kaliteli ve tam doldurulmamış anketler ayıklanarak 281 kullanılabilir soru formuna ulaşılmıştır. Verilerin analizinde yapısal eşitlik modellemesi kullanılmıştır. Gerçekleştirilen analiz sonuçlarına göre Facebook reklamlarına olan tutum ve tutumun öncülleri reklamları görmemek için ödeme niyetine olumsuz yönde etki etmektedir.

Rural tourism in Turkey has not received the interest it deserves compared to European countries. Theoretical studies along with applied projects are needed to increasethe awareness and draw interest to this important tourism area among populace and decision makers. The lack of extensive studies in Turkey creates an important research gap. To address this gap and improve the competitiveness of Turkey as a rural tourism destination, various applications that can improve awareness and attract interest are proposed in this study. Buyukcekmece Lake and Igneada Flood plain Forests were chosen as the application areas that have natural resources and unique historical heritage however lack amenities and relevant marketing activities to create interest. In this study both the destination competitiveness theories and worldwide applied best practices were analyzed. In this way a comparative analysis was carried out to assess and improve the rural tourism potential of these regions. Following the analysis, educational activities, agro/eco-tourism activities, touristic facilitiesthat can be constructed within the legal framework are proposed in detail. Establishment of a rural marketplace, development of nearby residential areas offeringaccommodation, food and commerce for visitors together with a tourism center were recommended asconstituents of a comprehensive rural tourism model. Keywords : Rural tourism, eco-tourism, destination marketing, tourism competitiveness, promoting rural tourism. JEL Classification: L83, O18, F13, M31

We aimed to compare dosimetric characteristics of conventional linear accerator-based treatment plans to those created using the robotic CyberKnife® (CK) treatment planning system for patients with early-stage lung cancer. Eight early-stage lung cancer patients treated with stereotactic body radiotherapy (SBRT) using a conventional linac-based (LIN) system were included in this study. New treatment plans were created for the patients with the CK treatment planning system in order to compare the two platforms' dosimetric characteristics. Planning computed tomographies (CT) were obtained in three phases: free-breathing, full exhalation and inhalation. The three GTVs were then added together for internal target volume (ITV) with LIN, whereas no ITV was used for CK. Planning target volumes (PTV) were constituted by adding 5-mm margin to GTV and ITV. Treatment plan was 54 Gy in three fractions. Five-field, seven-field, and dynamic-conformal arc planning techniques were used in LIN plans. Plans were compared according to dose heterogenity (Dmax-maximum dose), volume of 54 Gy (V54) and 27 Gy isodose (V27), conformity index (CI54 and CI27) and lung volumes. PTVs were significantly smaller in CK plans (p = 0.012). Dmax was significantly lower in ARC plans (p = 0.01). Among all plans, CK had significantly tightest isodose shell received 54 Gy and 27 Gy (p = 0.0001). Among LIN plans, V54 was significantly (p = 0.03) smaller in ARC plans; but no difference was observed for V27 values. LIN plans have better plan quality (CI27 and CI54) than CK. No statistically significant difference was observed for lung volumes. CK plans had superior V54 and V27 values compared to LIN plans due to smaller PTV. LIN plans had better CI27 and CI54 values. Advantages of LIN treatment were no neccessity for fiducial marker use, which may cause pneumothorax, and significantly shorter beam-on treatment times. Both CK and LIN methods are suitable for lung SBRT.

A set of general purpose two-dimensional single-field finite-difference time-domain updating equations for solving oblique incidence electromagnetic problems is derived. The traditional FDTD updating equations are based on Maxwell's curl equations whereas the single-field FDTD updating equations are based on the vector wave equation. Performance analyses of the single-field formulation in terms of CPU time and memory requirement are presented along with numerical validation. It was observed that the single-field method is more efficient than the traditional FDTD formulation in terms of speed and memory requirements for oblique incident problems.

PURPOSE: Robotic stereotactic hypofractionated radiotherapy (SRT) become an important modality in the treatment of cranial meningiomas. In this study, we analysed the treatment parameters and outcomes of our cranial meningioma patients treated with SRT. MATERIALS AND METHODS: Between 2009 and 2013, 103 cranial meningioma lesions of 93 patients were treated with CyberKnife (Accuray®) Stereotactic Radiosurgery Unit. 42 patients (45%) received SRT as primary modality, and 51 patients ( 55 %) received postoperatively. Six patients have treated with external beam radiotherapy. Of the 103 cases, 69 of the lesions were located basally, 34 of them nonbasally. The most common symptoms in patients with basal tumours (38 patients, 58%) was detoriation in the visual field and the restriction of the eye movements and in patients with non-basal tumours (8 patients, 26%) was headache. In 33 patients (32%) tumours were located just adjacent to the optic apparatus or brain stem, 27 of them (26%) were located close (