Recep Tayyip Erdoğan Üniversitesi Kurumsal Akademik Arşivi
DSpace@RTEÜ, Recep Tayyip Erdoğan Üniversitesi tarafından doğrudan ve dolaylı olarak yayınlanan; kitap, makale, tez, bildiri, rapor, araştırma verisi gibi tüm akademik kaynakları uluslararası standartlarda dijital ortamda depolar, Üniversitenin akademik performansını izlemeye aracılık eder, kaynakları uzun süreli saklar ve yayınların etkisini artırmak için telif haklarına uygun olarak Açık Erişime sunar.
Güncel Gönderiler
Green energy, pollution, and ecological resilience in China's tourism
(Wiley, 2025) Anser, Muhammad Khalid; Nassani, Abdelmohsen A.; Al-aiban, Khalid M.; Zaman, Khalid; Haffar, Mohamed
In recent decades, China's environmental problems and rapid urbanization redirected the course of its tourism industry. Against the backdrop of increasing alarm on climate change, air quality pollution, and energy resources sustainability, it is now imperative to understand their collective impact on tourism. The adoption of green energy, environmental pollution, and tourist arrivals are interrelated in this study, centering on China's dynamic tourism environment. Spanning from 1975 to 2022, the study employs the Generalized Method of Moments (GMM) estimator for parameter estimates. The findings reveal a negative relationship between international visitor arrivals and factors such as renewable energy consumption, economic development, and transit services. Conversely, the average temperature emerges as a significant factor that positively influences the potential for international tourism. Granger causality estimates support several hypotheses, including the notion that tourism drives carbon emissions and economic development, tourism propels transport services, renewable energy fuels economic growth, emissions drive economic growth, and temperature influences emissions within a nation. The results can foster the development of environmentally conscious and economically resilient tourist sectors.
Powering the transition: geoscientific insights and policy levers for global renewable energy investment, pricing reforms and decarbonization pathways towards SDG 7 and SDG 13
(Springer, 2025) Munir, Saqib; Anser, Muhammad Khalid; Khan, Aqil Waqar; Alam, Md Shabbir; Aamir, Alamzeb; Zaman, Khalid
The rapid shift towards renewable energy sources underscores the urgent need for comprehensive and timely solutions to mitigate carbon emissions. This study provides a detailed analysis of the factors that led to a reduction in carbon emissions in a panel of eighty-three nations, including industrialized and developing countries, from 1996 to 2022. The study used the autoregressive distributed lag model to evaluate energy pricing systems, efficiency metrics, private investments, renewable energy utilization, government regulations, and efficiency standards throughout this pivotal transition. The findings show a significant negative relationship between renewable energy consumption and carbon emissions, prioritizing renewable energy to achieve the aim of decarbonization in both the short and long term. The current national policy support and international energy cooperation level must be revised to achieve global sustainability goals. Although achieving energy synergy across sectors is essential for long-term carbon emission reduction, the initial decrease in energy prices reduces emissions in the short term. Energy efficiency initially mitigates carbon emissions but ultimately exacerbates them. Private energy investment gradually increases carbon emissions, likely due to continued dependence on carbon-intensive technologies. These results indicate that it is crucial to prioritize renewable energy and promote collaboration across different sectors to achieve long-term sustainability. Additionally, governments should enhance energy efficiency and encourage private investment in environmentally friendly technologies to accomplish long-term decarbonization objectives.
Thermal performance enhancement of solar collectors through optimization of outlet temperature
(Wiley, 2025) Abdel-aziz, Moataz M.; Khelifa, Abdelkrim; Attia, Mohammed El Hadi; Cüce, Erdem; Kabeel, Abd Elnaby
Solar thermal collectors play a pivotal role in harnessing solar energy for heating applications, yet achieving consistent outlet temperatures remains a critical challenge for efficiency and practicality. This study addresses the optimization of solar collectors to maintain a constant outlet temperature of 50 degrees C, a key requirement for residential and industrial applications. A simplified model based on energy equations was developed, coupled with computational fluid dynamics analysis, to derive design-ready formulas for collector size and fluid mass flow rate. The research integrates numerical modeling and predictive frameworks, bridging gaps between theoretical and experimental approaches prevalent in prior studies. Key findings reveal an optimal collector length range of 0.537-0.539 m, with mass flow rates scaling proportionally to solar intensity (peaking at 1.049 kg/h at 1000 W/m2). The Nusselt number reached 124.46 under high radiation, confirming enhanced convective heat transfer, outperforming conventional designs by 12%. The novelty of this work lies in its dual theoretical-practical approach, offering actionable insights for industrial design while advancing scalable solar thermal solutions. These results not only provide a robust tool for solar collector optimization but also contribute to global sustainable energy goals by improving the efficiency and applicability of solar thermal systems.
HBV infection drives PSMB5-dependent proteasomal activation in humanized mice and HBV-associated HCC
(Multidisciplinary Digital Publishing Institute (MDPI), 2025) Jannuzzi, Ayse Tarbin; Sarı, Gülce; Arslan-Eseryel, Sema; Zeybel, Müjdat; Yılmaz, Yusuf; Eren, Fatih; Karademir-Yilmaz, Betul
Hepatocellular carcinoma (HCC), the most common primary liver malignancy worldwide, is strongly associated with chronic Hepatitis B Virus (HBV) infection, a significant risk factor. The ubiquitin-proteasome system, central to protein degradation, cellular homeostasis, and cell cycle regulation, has been implicated in the pathogenesis of several cancers, including HCC. Despite this, the specific expression patterns of proteasomal subunits during HBV infection and HBV-induced HCC, as well as the association between mRNA expression of proteasomal subunits and proteasomal activity, remain poorly defined. To address this critical knowledge gap, we analyzed mRNA expression profiles of proteasomal subunits in HBV-infected humanized mouse models to uncover HBV-specific molecular alterations. Our findings revealed that the chymotrypsin-like activity (beta 5) subunit of the proteasome (PSMB5) is consistently overexpressed following HBV infection. Functional studies demonstrated that beta 5 deficiency decreases MHC I levels on the cell surface and leads to the accumulation of ubiquitinated proteins, establishing a direct link between beta 5 overexpression and increased proteasomal activity. Concordantly, HBV-infected patient livers-regardless of HCC status-displayed elevated beta 5 mRNA/protein levels and enhanced chymotrypsin-like activity. Additionally, analysis of Protein Atlas data revealed that elevated beta 5 mRNA expression correlates with poor clinical prognosis in HCC patients. In summary, this study highlights how HBV infection induces significant alterations in proteasome function by elevating beta 5 expression and activity in human and mouse livers. These findings underscore the critical role of proteasomal dysregulation in HBV-associated liver pathology and provide new insights into its involvement in HCC development. Understanding the interplay between HBV infection and proteasome dynamics offers a valuable avenue for the identification of novel therapeutic targets and biomarkers in HCC.
Evaluation of scour effects on structural integrity of highway bridges
(Taylor and Francis Ltd., 2025) Ertürk Atmaca, Esin; Marangoz, Hasan Oğulcan; Okur, Fatih Yesevi; Sunca, Fezayil; Baltaci, Alihan; Şahin, Muhammed Cihat; Altunışık, Ahmet Can
Scour, defined as water-induced erosion of soil around bridge piers, poses a significant threat to the stability and safety of bridges. Investigation of scour effects around the bridge piers is essential to ensure the long-term performance of bridges. This study examines the effects of local scour on the structural integrity of highway bridges by integrating on-site measurements, 3D computational fluid dynamics (CFD) simulations, and nonlinear finite element (FE) analysis. A highway bridge located over the Senoz Stream in & Ccedil;ayeli, Rize (T & uuml;rkiye), which suffered significant pier damage due to time-induced local scour, is considered. Since site investigation on the damaged bridge was not feasible, a nearby structurally identical bridge was selected for ambient vibration testing and numerical simulations. The local scour depth around bridge piers was estimated for different scenarios using validated 3D CFD simulations based on a synthetic flow input derived from different return periods calculated using the Gumbel distribution. The scour depth was then incorporated into a nonlinear FE model using a Concrete Damage Plasticity (CDP) approach to simulate failure mechanisms. The numerically obtained damage patterns were found to closely match the actual collapse observed in the damaged bridge. The novelty of this study lies in the integrated use of field-based modal testing, advanced CFD scour modelling, and nonlinear damage assessment to realistically simulate scour-induced bridge failure. The results emphasise the importance of coupling hydraulic and structural analyses to improve bridge safety assessments under complex environmental hazards.
