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Global Research on Cyberchondria: Scientometric and Visual Analysis From 2003 to 2022
No full textThis study aims to summarise the research themes, hotspots, and boundaries in the field of cyberchondria using scientometrics and visual analysis methods. Until 31 December 2022, 181 publications (165 articles, 16 reviews) were identified under the topic of 'cyberchondria' in the Web of Science Core Collection database. VOSviewer was used for analysis. It was observed that publications related to cyberchondria have rapidly developed into a research area in the last 4 years, constituting 79.0% (n = 143) of the total publications. The most common co-occurring keywords are 'cyberchondria', 'health anxiety', and 'COVID-19'. Clusters representing three different themes were obtained by conducting co-occurring keyword analysis. The first and largest cluster comprises 'COVID-19', 'anxiety', and 'internet addiction', the second cluster includes 'cyberchondria' and 'health anxiety', and the third cluster centres around 'health information' and 'health education' keywords. This study has mapped out the information landscape of cyberchondria research over the past 20 years using scientometric and visual analysis methods. The significant increase in recent years indicates a diversification and continued growth in studies conducted in this field. By presenting the general state of the field, this study provides valuable insights for future research endeavours
Investigation of the effect of shallow and deep cryogenic treatment on wear and impact performance of DIN 1.2344 steel
No full textHot work tool steels are preferred in different areas of industry due to their high toughness values and high impact resistance at high temperatures. Although there are many studies in the literature on DIN 1.2344 hot work tool steel, which is widely used in hot work tool steels, it has been determined that the studies examining the effects of cryogenic treatment on this material are limited. In this study, hardness, impact, tensile, wear tests were applied on DIN 1.2344 hot work tool steel and microstructure examination was carried out. In the study, the effects of shallow cryogenic treatment (SCT) and deep cryogenic treatment (DCT) at two different waiting times on mechanical properties (microhardness, macrohardness, yield and tensile strength, elongation amount, impact energy) were investigated compared to the conventional heat treated (CHT) sample. Microstructure, surface roughness and wear performance were investigated as a result of wear tests. As a result, it was found that shallow and deep cryogenic treatment provided 1.34%, 9.31% and 13% improvement on wear resistance for SCT-12, SCT-24 and DCT-36, respectively, compared to conventional heat treatment. In terms of impact resistance, the highest value was 2.37% improvement in DCT sample
Performance evaluation of selected airports: A case of Turkey
No full textHavacılık sekt͏örü ülkelerin ekonomik ilerlemesi için olmazsa olmaz͏ken aynı zamanda uluslararası ticaret ve turizm gibi çeşitl͏i alanl͏arda stratejik öneme sahiptir. Sektörün önemli ͏bileşenl͏erinden olan havalimanları, yolcu ve kargo taşımacılığındaki operasyone͏l et͏kinlikleriyle dikkat çekmektedir. Teknolojideki gelişmeler ve artan ͏rekabe͏tle b͏irlikte h͏avalimanı işletmecilerinin operasyonel süreçlerini optimize etmeleri ve k͏aynakla͏rı etkin kullanma͏l͏arı bir zorunluluk haline gelmektedir. Havalimanlarının etkinlik analizi,͏ optimal kayna͏k kull͏anımı ve performans değerlendirmesine odaklanan ͏ar͏aştırm͏alar͏da önemli bir araştırma konusu haline gelmiştir. Veri Z͏arflama͏ Analizi (V͏ZA) gibi modern teknikler, havalimanlarının ͏etkinlik seviyelerini ölçmek ve karşıla͏ştırmak için güçlü bir çerçeve sağlayarak bu değerlendirmeler ͏için sıklıkla kullanılmaktadır. Çalışmamızda, ͏Türkiye'deki seçilmiş havalimanlarının etkinliğini VZA yöntemi ile incelemeyi amaçlamaktayız. Çalışmada Devlet Hava Meydanları İşletmesi (DHMI) tarafından yayınlanan 2012-2023 yıllarına ait veriler kullanılarak, farklı havalimanlarının etkinlik düzeyleri karşılaştırılmış ve düşük performans gösteren birimler için iyileştirme ͏önerileri sunulmuştur. Bu değerlendirme sırasında terminal ͏binası alanı, personel sayısı, operasyonel giderler ve pist uzunluğu gibi girdiler dikkate alınırken, uçak sayısı, yolcu sayısı, kargo hacmi ve gelir rakamları gibi ͏çıktılar değerlendirilmiştir. Çalı͏şma bulgula͏rının,͏ hem y͏er͏el ͏hem de küresel͏ ölçekte havalimanlarının performans͏ yön͏etimini iyileştirmeye v͏e s͏ektörel politi͏kala͏r geliştirilmesine yardımcı olacağını düşünmekteyiz. Önümüzde͏ki bölümlerde, literatürdeki araştırmalar, kullanılan m͏etodolojiler, analiz sonuçları ve politika öner͏ileri kapsamlı şekilde ele alınacakt͏ır.The aviation industry In the contemporary context, the aviation sector is indispensable for the economic progress of nations and holds strategic significance in diverse areas such as international trade and tourism. Among its critical components, airports stand out due to their operational effectiveness in both passenger and cargo transportation. With advancements in technology and intensifying competition, it has become imperative for airport operators to optimize their operational processes and utilize resources efficiently. Airport performance analysis has emerged as a pivotal research topic, focusing on optimal resource utilization and performance evaluation. Modern techniques, notably Data Envelopment Analysis (DEA), provide a robust framework for measuring and comparing the efficiency levels of airports by accounting for various inputs and outputs. In this study, we aim to examine the efficiency of selected airports in Turkey. Utilizing data published by the State Airports Administration (DHMI) for the period 2012–2023, the performance levels of different airports are compared, and improvement recommendations are offered for underperforming units. Inputs such as terminal building area, personnel numbers, operational expenditures, and runway length were considered, while outputs including the number of aircraft, passenger count, cargo volume, and revenue were evaluated. We posit that the findings of this research will contribute to enhancing airport performance management and to the development of sectoral policies on both local and global scales. The subsequent sections will comprehensively address the literature, methodologies employed, analytical results, and policy recommendations
Phenotypic and Genotypic Antibiotic Resistance of Bacteria Isolated from Ready-to-eat Salted Seafood
No full textSafe food production faces significant challenges from both disease-causing bacteria and antibioticresistant bacteria, as both pose serious risks to public health and food safety. This study investigated the presence of antibiotic-resistant bacteria in salted seafood (lakerda) samples obtained from fishermen and fish markets. Phenotypic analysis revealed that lakerda samples collected from fishermen contained bacteria with multi-antibiotic resistance, including Pseudomonas fluorescens, Staphylococcus haemolyticus, and Staphylococcus equorum. Carnobacterium maltaromaticum, Carnobacterium mobile, and Vibrio hibernica species were isolated in larkerda samples sold by fish markets. It was determined that among isolated bacteria, V. rumoiensis did not contain any of the genotypically tested genes. However, P. fluorescens carried blaTEM, qnrB, qnrS, blaZ, and msrA; S. haemolyticus harbored blaTEM, tetK, dfrD, blaZ, msrA, msrB, and mecA; C. maltaromaticum possessed blaTEM, qnrA, qnrB, qnrS, strA-strB, aphAI-IAB, and mecA; C. mobile included blaTEM, blaZ, msrA, dfrD, and mecA; and V. hibernica carried blaTEM, blaZ, mecA, and VanA. In addition, S. pasteuri and S. equorum had the mecA resistance gene. In conclusion, public health needs to provide hygiene conditions in the preparation of lakerda, determine the ways of transmission, take precautions, and raise awareness of producers and consumers.Canakkale Onsekiz Mart University Scientific Research Projects Coordination Unit [FDK-2020-3334]This study is prepared from the PhD thesis of the first author, Dilek KAHRAMAN YILMAZ (supervision: Prof.Dr. Nermin BER & Idot;K), under the support of Canakkale Onsekiz Mart University Scientific Research Projects Coordination Unit with the project numbered FDK-2020-3334
Formation of an academic diaspora: A study of scholars from Turkey in the higher education sector in Britain
No full textThis is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution andreproduction in any medium, provided the original work is properly cited.The internationalisation of higher education has revealed the importance of understanding the formation and dynamics of academic diasporas. Most studies focus on cohesive academic diasporas, overlooking fragmentation in diasporas as a central concern. In this paper, we define and theorise fragmented academic diaspora. The emergence of a highly fragmented diaspora of scholars from Turkey in the British higher education sector presents an ideal opportunity to examine the notion of a fragmented academic diaspora. Based on an online study of 20 scholars from Turkey in British academia, this paper investigates the formation of an academic diaspora fragmented across social fault lines. We examine the factors driving the formation of a fragmented academic diaspora, the boundaries defining this community and the challenges it faces. Additionally, we discuss these scholars' professional and personal experiences and investigate their integration into the academic landscape of Britain. Based on the expectations and aspirations of the participants, we propose strategies to leverage fragmentation within this academic diaspora as a pathway to fostering synergies amidst fragmentation and divisiveness
In silico evaluation of toxic effects of benalaxyl-m on bees
No full textBu çalışmada, Benalaxyl-M maddesinin bal arıları (Apis mellifera) üzerindeki akut toksik etkileri, makine öğrenimi tabanlı bir QSAR (Kantitatif Yapı-Aktivite İlişkisi) aracı olan BeeToxAI kullanılarak in silico yöntemlerle değerlendirilmiştir. Analiz sonuçları, Benalaxyl-M'nin bal arıları için akut oral ve kontakt toksisite açısından toksik olmadığını (%83-86 güvenilirlik) göstermiştir. Uygulanabilirlik Alanı analizi, tahminlerin güvenilir olduğunu doğrularken, katkı haritaları moleküldeki toksisiteye katkı yapan fonksiyonel grupları belirlemede kullanılmıştır. Elde edilen bulgular, Benalaxyl-M'nin bal arıları üzerindeki düşük akut riskini ortaya koysa da, sonuçların deneysel çalışmalarla desteklenmesi önerilmektedir. Bu çalışma, pestisitlerin ekotoksikolojik risk değerlendirmelerinde yapay zeka tabanlı araçların potansiyelini vurgulamaktadırThis study evaluated the acute toxic effects of Benalaxyl-M on honey bees (Apis mellifera) using BeeToxAI, a machine learning-based QSAR (Quantitative Structure-Activity Relationship) tool, through in silico methods. The analysis results indicated that Benalaxyl-M is non-toxic in terms of acute oral and contact toxicity for honey bees (83-86% reliability). The Applicability Domain analysis confirmed the reliability of the predictions, while contribution maps identified functional groups contributing to toxicity. Although the findings suggest a low acute risk of Benalaxyl-M to honey bees, experimental validation is recommended. This study highlights the potential of AI-based tools in the ecotoxicological risk assessment of pesticides
Comparison of piperacillin-tazobactam and vancomycin (TZP-VAN) with piperacillin-tazobactam and teicoplanin (TZP-TEI) for the risk of acute kidney injury (CONCOMITANT): A prospective observational, multinational, multi-centre cohort study
No full textObjective: Both vancomycin (VAN) and teicoplanin (TEI) augment the risk of acute kidney injury (AKI) when combined with piperacillin-tazobactam (TZP). We aimed to compare the risk of AKI among patients receiving TZP-VAN vs. TZP-TEI. Methods: This was a prospective, multinational, multicentre cohort study conducted in 12 centres from Turkiye, Italy, and Spain between 1 June 2022, and 31 December 2023. The primary outcome was the occurrence of AKI between the first day of antibiotic treatment and the third day after completing therapy, according to the Kidney Disease Improving Global Outcomes criteria. Multivariable logistic regression and propensity-score match analyses were employed to adjust for confounding variables. Stratified Kaplan- Meier analysis was used to assess the time-to-AKI between the comparison groups. Results: Of 187 patients (TZP-TEI, n = 102; TZP-VAN, n = 85), the AKI occurred in 21 patients (24.7%) who received TZP-VAN and in 15 patients (14.7%) with TZP-TEI (unadjusted odds ratio [OR], 1.90; 95% CI: 0.91-3.97; P = 0.087). After adjusting for confounding variables with multivariable analysis, TZP-VAN was not associated with increased odds of AKI compared with TZP-TEI; with an adjusted OR of 2.24 (95% CI: 0.78-6.42; P = 0.133). In propensity-score matched analysis ( n = 49 pairs), the AKI risk was similar between the two groups (OR, 2.10; 95% CI: 0.67-6.50; P = 0.199). The stratified Kaplan-Meier analysis indicated no difference between the treatment groups in terms of time-to-AKI (log-rank test, P = 0.107). Conclusions: The risk of AKI in TZP-VAN was similar to that in TZP-TEI. These results should be confirmed in randomized controlled trials.Hacettepe University Scientific Re-search Coordination Unit [THD-2022-20012]This study was supported by Hacettepe University Scientific Re-search Coordination Unit (Project ID: THD-2022-20012)
The relationship between preschool teacher candidates' levels of liking children and their levels of supporting learner autonomy
No full textBu araştırmada okul öncesi öğretmen adaylarının çocuk sevme düzeyleriyle öğrenen özerkliğini destekleme düzeyleri arasındaki ilişkinin ortaya çıkarılması amaçlanmıştır. Çalışmada nicel araştırma yöntemlerinden ilişkisel tarama modeli kullanılmıştır. Bu amaç doğrultusunda araştırmanın evrenini 2023-2024 öğretim yılında Çanakkale Onsekiz Mart Üniversitesi Temel Eğitim Bölümü Okul Öncesi Öğretmenliği Anabilim Dalında eğitimini sürdüren 1., 2., 3. ve 4. sınıf öğrencileri oluşturmaktadır. Araştırmanın örneklemini ise seçkisiz yolla belirlenmiş toplam 222 okul öncesi öğretmeni adayı oluşturmuştur. Örnekleme uygulanan "Kişisel Bilgi Formu" aracılığıyla katılımcıların demografik özellikleri elde edilmiştir. "Barnett Çocuk Sevme Ölçeği" ile okul öncesi öğretmen adaylarının çocuk sevme düzeylerini ve "Öğrenen Özerkliğini Destekleme Ölçeği" ile de okul öncesi öğretmen adaylarının öğrenen özerkliğini ne derecede desteklediklerini ortaya çıkarmak amacıyla araştırmanın nicel verileri toplanmıştır. Araştırmadan elde edilen nicel veriler iki veri kodlayıcısı tarafından incelenmiş olup SPSS programı ile analiz edilmiştir. Verilerin çarpıklık ve basıklık katsayıları normal dağılım göstermemesi sebebiyle nonparametrik analiz tekniklerinden Mann Whitney-U testi seçilip uygulamaya alınmıştır. Araştırma neticesinde okul öncesi öğretmen adaylarının çocuk sevgilerinin yüksek seviyede olduğu görülmüştür. Farklı demografik özelliklere göre çocuk sevme düzeyleri incelenerek açıklanmıştır. Okul öncesi öğretmen adaylarının öğrenen özerkliğini destekleme düzeyleri incelendiğinde ölçeğin tamamında ve alt boyutlarının tümünde "Hiçbir zaman" yanıtını verdikleri ortaya çıkmıştır. Bu kapsamda farklı demografik özellikler açısından öğrenen özerkliğini destekleme düzeyleri incelenip sonuçlar analiz edilmiştir. Son olarak elde edilen veriler dahilinde gelecek çalışmalar için önerilerde bulunulmuştur.In this study, the relationship between the degree of impairment in children and the support for learner autonomy of preschool teacher candidates is revealed. The study used the relational screening model, one of the beautiful research methods. The universe of the education for this purpose consists of 1st, 2nd, 3rd and 4th grades continuing their education in the Preschool Teaching Department of the Basic Education Department of Çanakkale Onsekiz Mart University in the 2023-2024 academic year. The content of the research was created by a total of 222 preschool teacher candidates determined randomly. Demographic characteristics were obtained through the "Personal Information Form" applied to the sample. Trained quantitative data were collected in order to reveal the level of child liking of preschool teacher candidates with the "Barnett Child Liking Scale" and the level of support preschool candidates for learner autonomy with the "Support for Learner Autonomy Scale". The beautiful data obtained from the research were examined by two data coders and analyzed with the SPSS program. Since the skewness and kurtosis coefficients of the data did not show normal distribution, Mann Whitney-U test formations, which are nonparametric analysis techniques, were applied. As a result of the research, it was seen that preschool teacher candidates had a high level of love for children. The level of deterioration in children was examined and shown according to different demographic structures. It was revealed that preschool teacher candidates who did not support learner autonomy, gave the answer "Never" in all of the increased performance and all of its sub-dimensions. The results were obtained by examining and analyzing the regional level of this skill learned in terms of different demographic characteristics. Finally, suggestions were made for future studies among the obtained data
Effects of incubator conditions and genetic factors on hatching traits and sex ratio in chickens and quails
No full textBu çalışma, tavuk ve bıldırcın embriyolarının farklı kuluçka dönemlerinde soğuk stresine karşı tepkilerini ve bıldırcınlarda embriyo kayıplarının genetik varyasyon sebeplerini incelemektedir. Tez çalışması tavuk ve bıldırcınlarda toplam 4 farklı genotip kullanılarak 3 ayrı çalışmada yürütülmüştür. İlk çalışmada 3 yumurtacı; ikincisinde 2 yumurtacı ve 1 etlik genotip; son çalışmada ise Japon bıldırcınları kullanılmıştır. İlk çalışma 15 °C'de erken dönem 4 saat (G1), geç dönem 4 saat (G2) ve her iki dönem 8 saat (G3) gruplarından oluşmuştur. İkinci çalışmada yumurtalar erken dönemde 6 saat (EDU1), 12 saat (EDU2) ve 18 saat (EDU3) boyunca 10 °C'de muhafaza edilmiştir. Geç dönemde 6 saat (GDU1), 12 saat (GDU2) ve 18 saat (GDU3) boyunca 10 °C sıcaklık uygulanmıştır. Bıldırcınlarda, 6 saat (BU1), 18 saat (BU2) ve 36 saat (BU3) boyunca 10 °C'de soğutma uygulanmıştır. Tavuk kontrol (K) ve bıldırcın kontrol (BK) gruplarına standart kuluçka koşulları uygulanmıştır. Genetik etkiler için de bıldırcınlarda 81 baba ve 130 anadan oluşan, 11 kuluçka dönemi incelenmiştir. Soğuk uygulamasının tavuk ve bıldırcınlarda çıkım ağırlığına (ÇA) etkisi gözlemlenmemiştir (P>0,05). Çıkım gücü bakımından gruplar arasında farklılık gözlenmezken (P>0,05), genotip etkisi önemlidir (P0.05). While no differences were observed among the groups in terms of hatchability (P>0.05), the genotype effect was significant (P<0.0001). Cold treatment prolonged the incubation period in both chickens and quails (P<0.0001). In quails, the direct heritability (h²) for HW was estimated at 0.15±0.07, and the maternal heritability was 0.67±0.10. The total embryo loss (TEL) heritability was found to be 0.19±0.01. Selection for TEL showed a slow but positive effect in the middle (rg=0.59) and late (rg=0.58) periods. Genotype-environment interaction was significant for embryo loss and sex ratio. Embryos can activate or suppress different genes depending on their environmental conditions and can develop tolerance to these conditions
Do uncertainties and risks have an impact on cryptocurrency returns? Evidence from the symmetric and asymmetric fourier quantile causality test
No full textThis paper explores the impact of uncertainties and risks on the returns of cryptocurrencies by considering the two dimensions of uncertainty sourcing from economic policy uncertainty and geopolitical risk. Therefore, we analyze whether there is a causality from the global economic policy uncertainty (GEPU) and geopolitical risk (GPR) to the cryptocurrency returns in the period from 2015:01 through 2023:05. In our analysis, we use the GEPU and GPR indexes as independent variables and the historical values of Bitcoin, Ethereum, Litecoin, Ripple, Monero, and Dash as dependent variables. We employ the Fourier augmented causality test considering the original series, and also the positive and negative components of the series. Our findings reveal that the GPR has predictive power for all cryptocurrencies while GEPU has not predictive power for only Bitcoin. Furthermore, we find evidence of the causality nexus that runs from negative shocks of GEPU to the negative shocks of Litecoin and Ripple, and from the negative shocks of GPR to the negative shocks of Litecoin and Monero indicating when there are significant decreases at the GEPU, these values can be used to predict the decreases of Litecoin and Ripple. Similarly, we can also imply it for the causality relationship from GPR to Litecoin and Monero. When we consider there might be a causal relationship not only between shocks of the same type but also between different types of shocks we find that there is unidirectional causality from negative shocks of GEPU to the positive shocks of Dash, Ethereum, and Monero at the high return phase, and from positive shocks of GEPU to the negative shocks of Ethereum, and from positive shocks of GPR to the negative components of Bitcoin, Ethereum, and Ripple at the bearish market conditions