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The Effect of the Israel-Hamas Conflict on Carbon Markets: Evidence from the European Union Emissions Trading System
No full textAim/purpose – This study investigates the impact of the Israel-Hamas conflict on carbon emission allowance prices within the European Union Emissions Trading System (EU ETS). Given the growing significance of geopolitical risks in carbon markets, this study examines the extent to which such conflicts influence spot and futures carbon prices, and whether these effects are short term or persistent. Design/methodology/approach – The study employs two complementary econometric techniques: event study methodology and wavelet analysis. The event study method captures short-term price reactions to the conflict, while wavelet analysis provides insights into both short-term and long-term dynamics. The dataset consists of daily trading prices of CO₂ emission allowances from June 1, 2022, to December 30, 2023, sourced from the Refinitiv Eikon database. The research design allows for the identification of market participants’ immediate reactions and the subsequent adjustment of market expectations. Findings – The empirical results indicate a divergence in the short-term responses of spot and futures carbon markets. The event study shows that the carbon spot market reacted positively to the onset of the Israel-Hamas conflict, whereas the carbon futures market reacted negatively. Wavelet analysis confirms this short-term divergence but also shows that, in the long term, both markets eventually move in the same direction. This suggests that short-term market dislocations driven by geopolitical shocks are temporary, and carbon markets tend to stabilize over time. Research implications/limitations – This study underscores the need to account for geopolitical risks when analyzing carbon market volatility. However, its focus on the EU ETS may limit the generalizability of the findings to other carbon markets. Additionally, the lack of detailed military emissions data prevents a direct analysis of such impacts. Future research should explore other carbon markets and incorporate more granular data on military-related emissions. Originality/value/contribution – This study is probably the first to examine the influence of the Israel-Hamas conflict on carbon markets, thereby filling a gap in the literature on geopolitical risks and carbon pricing. Unlike prior studies that assume parallel movements in spot and futures markets, this research reveals a short-term divergence that eventually converges in the long run. The findings provide policymakers and market participants with valuable insights by emphasizing the role of geopolitical shocks in shaping carbon market dynamics and advocating risk mitigation strategies for emissions trading systems. © 2025 Eyüp Tanıl et al., published by University of Economics in Katowice
Blasting Excavation for Connecting a New Tunnel to an Active Sewage Tunnel in a Wastewater Treatment Plant
No full textThis study presents the controlled blasting method used to excavate the buffer zone between a new connection tunnel and an active sewage tunnel operating at full capacity at the Tuzla Advanced Biological Wastewater Treatment Plant in Istanbul, owned by ISKI. Treating up to 650,000 m3 of wastewater daily for a population of 2.6 million, the plant required new treatment units to be connected to the existing system due to increased capacity needs. Since the existing 2,200 mm-diameter sewage tunnel, built in 1998, could not be safely or economically shut down, blasting was selected for the excavation of the 40–60 cm thick rock buffer zone. The blast face area was 9.7 m2 and consisted of limestone with 25–35 MPa compressive strength. Due to unknown properties of the reinforced concrete lining of the existing tunnel and the presence of sensitive equipment above, a detailed risk analysis was conducted. Blasting design limited explosive charge per delay to 3.2 kg to stay below 15 mm/s particle velocity and 135 dB air shock. Electronic detonators and 27 mm cartridges in 33 mm boreholes ensured safety and precision. A total of 112 holes and 20 kg of explosives were used. Maximum measured vibration was 5.21 mm/s and air shock 132.3 dB. The operation achieved full breakthrough without disrupting sewage flow or causing structural damage. © 2025 International Multidisciplinary Scientific Geoconference. All rights reserved
The Effect of Fluoride Varnish on the Color Stability and Surface Microhardness of Bioactive Restorative Materials: An in Vitro Study
No full textThe aim of the study is to evaluate the effect of fluoride varnishes on both the color stability and surface microhardness of different fluoride-releasing restorative materials exposed to beverages commonly consumed by children . This study was conducted as an in vitro experimental study design. Three different restorative materials (Dyract XP, Beautifil II, and Cention N) and a colorless fluoride varnish were used. The solutions in which the samples were immersed were selected as beverages commonly preferred by children: cherry juice, chocolate milk, and cola. Color changes of the samples were measured using a spectrophotometer at 1, 7, 14, and 28 days and calculated according to the CIEDE2000 total color difference formula. Surface microhardness values were measured using a digital microhardness testing device at 1 and 28 days. To assess the effects of variables and their interactions in repeated observation designs, generalized linear models and generalized linear mixed models were fitted. Following model estimation, Tukey's-adjusted estimated marginal means were computed to identify significant pairwise differences. Fluoride-releasing restorative materials exhibited varying degrees of color change and decrease in surface microhardness when immersed in different staining solutions. Among the tested materials, Cention N demonstrated the greatest color stability (Delta E=1.01 for fluoride applied group, Delta E=1.45 for the group without fluoride application) and least reduction in surface microhardness. Fluoride application initially caused a slight discoloration immediately after application. However, following immersion in different solutions, fluoride application appeared to enhance color stability (Delta E=1.59 in the varnish-applied group, Delta E=2.21 in the group without varnish application), but did not have a statistically significant effect on the surface microhardness. A negative correlation was observed between color change and surface microhardness; as the surface microhardness decreased, the extent of color change increased. This study highlights the prominent role of intraoral environmental factors in influencing the durability and aesthetic properties of fluoride-releasing restorative materials. Topical fluoride application has a beneficial effect on the color stability with a more pronounced effect observed with Cention N.Science Citation Index Expande
The Investigation of the Relationship Between Pain and the Flexibility of Muscles Affecting Pelvic Position in Women with Primary Dysmenorrhea
No full textBu çalışmanın amacı primer dismenoresi olan kadınlarda pelvisin pozisyonunu etkileyen kasların esnekliğine bakılarak dismenore üzerindeki etkilerini incelemektir. Çalışmaya primer dismenoresi olan 18-45 yaş aralığında 75 kadın dahil edildi. Gönüllü katılımcıların sosyodemografik özelliklerine, özgeçmişlerine ve hastalık geçmişine ait detaylar, araştırmacıların oluşturduğu 'Dismenore Bilgi Formu' ile kaydedildi. Menstrüel ağrı şiddeti Görsel analog skala ile değerlendirilip kaydedildi. Katılımcıların fiziksel aktiviteleri ''Uluslararası Fiziksel Aktivite Anketi'' Kısa Formu kullanılarak değerlendirildi. Pelvis pozisyonunu etkileyebilecek kas grupları; lumbal ekstansörler, kalça fleksörleri, hamstring kasları mezura ve gonyometre kullanılarak esneklik açısından değerlendirildi. Çalışmamızda primer dismenoresi olan kadınların %68'inin aktif, %32'sinin ise sedanter bireylerden oluştuğu tespit edildi. Ağrı şiddeti ölçümlerinde ağrı süresi arttıkça ağrı şiddeti puan ortalamaları istatistiksel olarak artmaktaydı. Hamstringlerin esneklik ortalamaları minimal aktif olanlardan istatistiksel olarak yüksekti (p<0,05). Ağrı süresi arttıkça Hamstringlerin esneklik ortalamaları istatistiksel olarak düşmekteydi (p<0,05). Kalça fleksörlerinin esneklik ölçümleri düzenli menstrüasyon yaşayanlarda 15,75 ± 3,19 cm, yaşamayanlarda 13,84 ± 2,61 cm iken düzenli menstrüasyon yaşayan kişilerin kalça fleksörlerinin esneklik ortalamaları istatistiksel olarak yüksekti (p<0,05). Bu çalışmada primer dismenoreli kadınlarda ağrı şiddeti ile Lumbal ekstansörlerin esnekliği arasında pozitif yönlü istatistiksel olarak anlamlı ilişki vardır (p<0,05). Kadınların ağrı şiddeti ile Hamstringlerin esnekliği arasında negatif yönlü istatistiksel olarak anlamlı ilişki vardır (p<0,05). Kadınların ağrı şiddeti ile kalça fleksörlerinin esnekliği arasında negatif yönlü istatistiksel olarak anlamlı ilişki vardır (p<0,05). Sonuçlarımızın klinikte Primer Dismenoreli kadınların değerlendirme ve tedavi yaklaşımları için katkı sağlayacağını düşünmekteyiz. Bu sayede Primer Dismenoreli kadınların tedavilerini küçük uyarlamalarla daha etkin hale getirebilmek için veri sağlayabileceğimizi umuyoruz.The aim of this study is to examine the effects of muscle flexibility, particularly those affecting pelvic position, on dysmenorrhea in women with primary dysmenorrhea. A total of 75 women aged between 18 and 45 years with primary dysmenorrhea were included in the study. Sociodemographic characteristics, medical history, and background of the volunteer participants were recorded using a 'Dysmenorrhea Information Form' created by the researchers. The severity of menstrüel pain was assessed and recorded using the Visual Analog Scale. Physical activity levels of the participants were evaluated using the Short Form of the 'International Physical Activity Questionnaire.' Muscle groups that could affect pelvic position—including lumbar extensors, hip flexors, and hamstrings— were assessed for flexibility using a tape measure and goniometer. In our study, it was determined that 68% of women with primary dysmenorrhea were physically active, while 32% were sedentary. In pain intensity assessments, as the duration of pain increased, the average pain intensity scores increased statistically. The average flexibility of the hamstrings was statistically higher in those who were minimally active (p<0.05). As the duration of pain increased, the average flexibility of the hamstrings decreased statistically (p<0.05). The flexibility measurements of the hip flexors were 15.75 ± 3.19 cm in women with regular menstruation and 13.84 ± 2.61 cm in those without; the average flexibility of the hip flexors was statistically higher in those with regular menstruation (p<0.05). In this study, there was a statistically significant positive correlation between pain intensity and lumbar extensor flexibility in women with primary dysmenorrhea (p<0.05). There was a statistically significant negative correlation between pain intensity and hamstring flexibility (p<0.05). Similarly, there was a statistically significant negative correlation between pain intensity and hip flexor flexibility (p<0.05). We believe that our results will contribute to the clinical evaluation and treatment approaches for women with primary dysmenorrhea. In this way, we hope to provide data that can help make treatments for women with primary dysmenorrhea more effective through small adjustments
Inventory Management With Deterioration and Trade-Credit Policy: A Path Toward Sustainability
No full textBackground: This research tackles the difficulty of dealing with deteriorating inventory model with sustainably while optimizing the annual total cost for retailers. For economic and environmental equilibrium, the model incorporates preservation technology to alleviate the deterioration rate and includes trade-credit policy to minimize the total annual cost. Moreover, carbon emission reduction via green technology is included to prevent environmental pollution. Methods: A sustainable inventory model is designed by assuming demand rate and production level as linear functions of time. The optimal cycle length and optimal order quantity are obtained by allowing carbon emission rate as a controllable variable. Further, the model is solved with the assistance of classical optimization techniques. Results: Numerical illustrations highlight the managerial implications, showing that appropriate credit policies enhance financial performance and reduce resource wastage and environmental impact. Conclusion: The sustainable inventory model presented here provides a complete framework for achieving economic profitability and environmental accountability. It offers applicable knowledge to decision-makers to maximize order policies, manage carbon emissions and develop efficient trade-credit plans for a deteriorating inventory systems. © 2025 World Scientific Publishing Company
Mathematical Analysis of Age-Structured Susceptibility in Campylobacteriosis Transmission Dynamics
No full textEmadifar, Homan/0000-0002-8034-1475; Ahmed, Karim K/0000-0003-0414-4960;Campylobacteriosis remains one of the leading causes of bacterial gastroenteritis worldwide, particularly affecting children and adults through contaminated food and water sources. This study develops and analyzes an age-structured mathemati-cal model for Campylobacteriosis transmission that incorporates mild and severe infection classes, as well as treatment and public awareness interventions. The total population is stratified into child and adult groups with age-dependent susceptibil-ity. The basic reproduction number, R-0, is derived using the next-generation matrix method and serves as a threshold parameter governing disease persistence. Analytical results reveal that the disease-free equilibrium is locally and globally asymptotically stable when R-0<1, and unstable otherwise. Sensitivity analysis identifies the transmission rates (beta) and awareness rate (u1) as the most influential parameters affecting disease spread. Numericalsimulations, performed using the fourth-order Runge-Kutta scheme in Maple 2024, demonstrate that the combined implementation of public awareness and treatment efforts under optimal control significantly reduces the infection burden. The study highlights that simultaneous awareness and treatment interventions are more effective than either control applied individually. These results provide quantitative insights for designing targeted public health strategies aimed at mitigating Campylobacteriosis transmission across age groups
The Mediterranean Diet and Its Effects on Fatigue
No full textThe Mediterranean diet (MD), characterized by high consumption of fruits, vegetables, whole grains, legumes, and olive oil, with a moderate intake of fish and poultry, is renowned for its numerous health benefits, including reduced risks of chronic diseases and enhanced cognitive function. This chapter delves into the MD’s potential role in mitigating fatigue, a condition affecting physical and cognitive performance. It explores the nutritional components of the MD that support energy metabolism, such as complex carbohydrates, high-quality proteins, and healthy fats, which provide sustained energy and reduce inflammation. This chapter also discusses the diet’s antioxidant and antiinflammatory properties, which combat oxidative stress, a key factor in fatigue. Clinical studies highlight the MD’s effectiveness in reducing fatigue in conditions like cancer and multiple sclerosis. Practical recommendations for incorporating the MD into daily life emphasize balanced, nutrient-dense meals that support overall well-being and energy levels. © 2026 Elsevier Inc. All rights are reserved, including those for text and data mining, AI training, and similar technologies
An Examination of Billiard Players' Mental Resilience, Anxiety, and Competitive Spirit Across Different Divisions
No full textBu çalışmanın temel amacı, farklı klasmanlardaki bilardo sporcularının zihinsel dayanıklılık, endişe ve mücadele düzeylerinin çeşitli demografik değişkenler açısından incelenmesidir. Bu araştırmanın evrenini, Türkiye'de farklı klasmanlarda (3 bant, snooker, pool) aktif olarak bilardo sporu ile ilgilenen lisanslı sporcular oluşturmaktadır. Örneklem ise, çalışmaya gönüllü olarak katılan ve veri toplama araçlarını eksiksiz yanıtlayan toplam 163 bilardo sporcusundan oluşmaktadır. Veriler, çevrim içi ortamda (Google Forms) toplanmıştır. Araştırmada veri toplama aracı olarak üç bölümden oluşan (Demografik Bilgi Formu, Zihinsel Dayanıklılık Ölçeği, Endişe Ölçeği ve Mücadele Etme Ölçeği) bir anket formu kullanılmıştır. Veri analiz yöntemleri olarak kişisel değişkenleri incelemek için betimleyici istatistiksel yöntemler, araştırma değişkenleri ve kişisel değişkenler arasındaki ilişkiyi incelemek için ve veri ölçüm araçlarından elde edilen puanların demografik değişkenlerle karşılaştırılmasında fark testleri kullanılmıştır. Araştırma bulgularına göre, katılımcıların, zihinsel dayanıklılık, endişe ve mücadele etme düzeyi puanları, cinsiyetine göre istatistiki bakımdan anlamlı farklılaşmamaktadır (p>0.05). Bunun yanında katılımcıların, zihinsel dayanıklılık ve mücadele etme düzeyi puanları, medeni durumuna göre istatistiki bakımdan anlamlı farklaşırken (p0.05). Araştırmada, cinsiyet durumuna göre bilardo sporcularının zihinsel dayanıklılık, endişe ve mücadele etme düzeyleri üzerinde anlamlı bir farklılık bulunmamıştır. MANOVA analizine göre cinsiyetin bu değişkenler üzerinde etkisi istatistiksel olarak anlamlı değildir ve etki büyüklüğü de küçük düzeydedir.The main purpose of this study is to examine the mental toughness, anxiety, and struggle levels of billiards athletes in different classifications in terms of various demographic variables. The population of this study consists of licensed athletes who are actively engaged in billiards sports in different classifications (3-cushion, snooker, pool) in Türkiye. The sample comprises a total of 163 billiards athletes who voluntarily participated in the study and completed the data collection tools in full. Data were collected through online platforms (e.g., Google Forms). A questionnaire form consisting of three sections (Demographic Information Form, Mental Toughness Scale, Anxiety Scale, and Struggle Scale) was used as the data collection tool in the study. Descriptive statistical methods were employed to examine personal variables, while difference tests were used to explore the relationship between research variables and demographic variables and to compare the scores obtained from the measurement tools. According to the research findings, the participants' mental toughness, anxiety, and struggle level scores do not differ statistically significantly according to their gender (p>0.05). Additionally, while the participants' mental toughness and struggle level scores differ statistically significantly according to their marital status (p0.05). Furthermore, no significant difference was found in the mental toughness, anxiety, and struggle levels of billiards athletes based on their gender. According to the MANOVA analysis, the effect of gender on these variables is not statistically significant, and the effect size is small
Life and Artistic Personality of Kastamonu Drummer Mahir Dağlıoğlu
No full text'Kastamonu davulcusu Mahir Dağlıoğlu'nun hayatı ve sanatçı kişiliği' başlıklı bu çalışma, ülkemizde nadiren yetişen yerel sanatçılardan biri olan ve 'Karayılan' lakabıyla tanınan Kastamonulu Mahir Dağlıoğlu'nun hayatını ve sanatçı kimliğini incelemeyi amaçlamaktadır. Bu çalışmada metodolojik yöntem olarak, Mahir Dağlıoğlu'nun hayatını ve sanatçı kimliğini şekillendiren unsurlar ile bugüne kadar gün yüzüne çıkmamış bilgilere ulaşmak amacıyla alan araştırması yapılmış ve gözlem yöntemi kullanılmıştır. Mahir Dağlıoğlu'nun 'oyun kurma' özelliği, 'Sepetçioğlu' oyununun figür incelemesi ve yazıya aktarımı gerçekleştirilmiştir. Mahir Dağlıoğlu'nun, sanatını icra ederken kullandığı kıyafet ve aksesuarları görsellerle desteklenerek detaylı açıklamalar ile ifade edilmiştir. Buna ek olarak, araştırma sürecinde elde edilen video kayıtları dijitalleştirilmiş, teknolojik kolaylaştırıcılıktan yararlanılarak eğitimsel kullanımı destekleyen kare kodlar oluşturulmuştur. Sonuç olarak, Mahir Dağlıoğlu'nun yaşamı ve sanatı aracılığıyla, ortaya koyduğu dansı ve oyun kurma becerisi akademiye kazandırılmış, bununla birlikte, Kastamonu davul kültürü yeniden okunmuş ve gelecek kuşaklara aktarılabilecek akademik bir içerik hâline getirilmiştir. Anahtar Kelimeler: Kastamonu, Davul, Mahir Dağlıoğlu, Oyun Kurma.This study, titled 'The Life and Artistic Identity of Kastamonu Drummer Mahir Dağlıoğlu', seeks to investigate the life trajectory and artistic identity of Mahir Dağlıoğlu, a native of Kastamonu who stands out as one of the few remaining local artists in Turkey and is widely recognized by the epithet 'Karayılan.' Methodologically, the research is grounded in ethnographic fieldwork and observational techniques, with the aim of elucidating the sociocultural factors that shaped Dağlıoğlu's artistic persona and of documenting information hitherto absent from the scholarly record. Within this framework, particular attention is devoted to Dağlıoğlu's distinctive practice of 'game-setting' (oyun kurma), which is analyzed in detail through a choreographic study and the notation of the dance 'Sepetçioğlu.' In addition, the costumes and accessories employed in his performances are systematically examined, supported by visual documentation. Furthermore, the video recordings obtained during the research process were digitized and QR codes were generated through technological facilitation to enhance their applicability in educational contexts. In conclusion, the study introduces Mahir Dağlıoğlu's unique contributions to dance and game-setting into the realm of academic discourse. Simultaneously, it reconsiders the drumming tradition of Kastamonu, reinterpreting and recontextualizing it as an academic resource capable of transmission to future generations. Keywords: Kastamonu, Drum, Mahir Dağlıoğlu, Game Setup
Screening for Specific Learning Difficulties in Children Aged 60-72 Months Attending Preschool Education Through Parental Mediation and Examining Teachers' Levels of Knowledge: The Case of Kocaeli
No full textBu araştırmanın amacı, okul öncesi eğitime devam eden 60-72 ay grubu çocukların ebeveynleri aracılığıyla ÖÖG risklerinin taranması ve okul öncesi öğretmenlerinin ÖÖG risk faktörlerine ilişkin bilgi düzeylerinin incelenmesidir. Betimsel tarama modeline dayalı olan bu çalışmada öğretmenlere 'Özgül Öğrenme Güçlüğüne İlişkin Soru Listesi' (Yiğiter, 2005), ebeveynlere ise 'Özgül Öğrenme Bozukluğu Tarama Ölçeği' (Oral, 2017) uygulanmıştır. Araştırmanın verileri, Kocaeli ilindeki bağımsız anaokullarında görev yapan 395 öğretmen ve 557 ebeveynden elde edilmiştir. Verilerin analizi sonucunda, öğretmenlerin büyük bir bölümünün ÖÖG konusunda bilgi sahibi olduğunu ifade etmesine rağmen özellikle zekâ düzeyi, fark edilme dönemi gibi kavramsal konularda bilgi eksiklikleri olduğu saptanmıştır. Benzer şekilde, ebeveynlerden elde edilen verilere göre ÖÖG'nin alt boyutlarından olan kavramsal beceriler ve motor becerilerde risk tarama puanları yüksekken kişilik özellikleri ve sosyal beceriler gibi alanlarda ise bu puanların düşük olduğu görülmüştür. Öğretmenlerin bilgi düzeylerinin; yaş, mesleki kıdem ve öğrenim durumu gibi demografik değişkenlere göre anlamlı farklılıklar gösterdiği gözlenmiştir. Ebeveynlerde ise 31-40 yaşa aralığındaki bireylerin çocuklarının ÖÖG risklerinde daha düşük tarama puanına sahip olduğu ortaya çıkmıştır. Anahtar Kelimeler: Özgül öğrenme güçlüğü, okul öncesi eğitim, öğrenme güçlüğü belirtileri. Tarih: 26.09.2025The purpose of this study is to screen for SLD risks among children aged 60-72 months attending preschool education through their parents and to examine preschool teachers' knowledge levels regarding SLD risk factors. Based on a descriptive screening model, the 'Questionnaire on Specific Learning Difficulties' (Yiğiter, 2005) was administered to teachers, and the 'Specific Learning Disorder Screening Scale' (Oral, 2017) was administered to parents. The research data were obtained from 395 teachers and 557 parents working in independent preschools in Kocaeli province. The analysis of the data revealed that although the majority of teachers stated that they had knowledge about SLD, they had knowledge gaps, particularly in conceptual issues such as intelligence level and detection period. Similarly, according to the data obtained from parents, risk screening scores were high in the conceptual skills and motor skills subdimensions of ÖÖG, while these scores were low in areas such as personality traits and social skills. Teachers' knowledge levels were found to show significant differences according to demographic variables such as age, professional seniority, and educational status. Among parents, individuals aged 31-40 were found to have lower screening scores for their children's SLD risks. Keywords: Specific Learning Disorder, Preschool Education, Learning Disorder Symptoms Date: 26.09.202