Sürdürülebilir Kalkınma Amaçları
Yazarlar
- Isik, Cem(6)
- Ongan, Serdar(6)
- Aydin, Rahman(5)
- Imamoglu, Ilyas Kays(5)
- Abd El-Aty, A. M.(1)
- Achazi, Andreas J.(1)
- Adeli, Mohsen(1)
- Agar, Erdal(1)
- Ahmad, Munir(1)
- Alvarado, Rafael(1)
- Alyafei, Mohammed(1)
- Amsalem, Patrick(1)
- Anlar, Pinar(1)
- Arslan, Gokhan(1)
- Avena-Bustillos, Roberto J.(1)
- Ay, Mizgin(1)
- Ayberkin, Doruk(1)
- Aydin, Buket(1)
- Aygun, Ali(1)
- Bartonitz, Florian(1)
- Bridges, David F.(1)
- Butuner, Selcuk(1)
- Cakir, Ozlem(1)
- Calina, Daniela(1)
- Cebeci, Fatma(1)
- Chiou, Bor-Sen(1)
- Cinar, Mehmet(1)
- Custódio, Luisa(1)
- Durul, Melekber Sulusoglu(1)
- Ercisli, Sezai(1)
- Fiebor, Alphonse(1)
- Gordeev, Georgy(1)
- Gueven, Sara Altun(1)
- Günlü, Ebru(1)
- Gürer, Eda Sonmez(1)
- Hacimuftuoglu, Ahmet(1)
- Hayat, Faisal(1)
- Imamoglu, Ilyas kays(1)
- Iriti, Marcello(1)
- Isik, Olcay(1)
Yayınlar
- MakaleYalnız künye2026Scopus SJRQ2Analyzing IPO Performance on Borsa Istanbul: A Hybrid Econometric and Machine Learning Framework (2013-2025)
Ayberkin, Doruk
This study examines the determinants of the performance of initial public offerings (IPOs) conducted by 237 firms across 38 sectors on the Istanbul Stock Exchange between 2013 and 2025, using a hybrid analytical framework. To analyze the impact of sector characteristics, firm-level financial indicators, supply structure, and market timing on the returns of USD-denominated IPOs, this study combines heteroskedasticity-resistant ordinary least squares (OLS) regression with tree-based ensemble machine learning algorithms (random forest, XGBoost) and benchmark models (support vector regression, artificial neural network). The distributional characteristics of returns from IPOs highlight the use of nonlinear modelling techniques characterized by high positive skewness (5.12) and excess kurtosis (45.24). Our findings reveal significant sectoral heterogeneity. According to the findings, the Financial Services and Fisheries sectors showed statistically significant superior performance, while the Metal Mining, Insurance, and Construction sectors underperformed. Transportation and Storage exhibited the highest point estimate but did not reach conventional significance levels. The XGBoost machine learning model, with an R 2 of 0.869 and a mean absolute error (MAE) of 17.87, achieved superior single-split prediction accuracy compared to the OLS method, which yielded an R 2 of 0.220. However, cross-validation analyses indicated that all models exhibited limited out-of-sample generalizability (best CV R 2 = 0.04). The Diebold-Mariano test, conducted to compare prediction performance, confirmed that the artificial neural network (ANN) model provided a statistically significant improvement over the OLS method (DM = 2.121, p = 0.034). The SHAP value analysis used in the models reveals how each feature affects the final predictions, the relative importance of each feature, and the model's dependence on feature interactions. It identifies the IPO price (USD), the USD/TRY exchange rate, and the size of the supply as the most effective estimators with economically significant nonlinear interactions. The study aims to demonstrate the comparative advantages and limitations of ensemble learning under abnormal financial data conditions by presenting detailed sectoral evidence across 38 sectors. In this way, it aims to contribute to the IPO literature in emerging market economies by offering viable policy recommendations for investors, issuers, and regulators in Turkish capital markets.
- MakaleAçık Erişim2026Scopus SJRQ1The Role of Women's Labor Law and Business Freedom in Achieving Sustainable Development Goals (SDGs) in OECD Countries
Isik, Cem; Ongan, Serdar; Isik, Olcay; Aydin, Rahman; Imamoglu, Ilyas Kays
Business freedom (FR) and women's labor law (WLL) are critical in achieving the SDGs. This research aims to test the effect of these two factors on the SDGs while also considering economic growth and energy efficiency, framing the analysis within the legal, economic, and environmental dynamics of the SDGs holistically. Fourier-augmented PANIC, cross-sectional dependence tests, panel OLS, bootstrap quantile regression, and panel Granger causality tests are applied for this aim. The OLS and bootstrap quantile regression analyses indicate that while FR negatively affects SDG at lower quantiles, these effects turn positive in higher quantiles. This can mean that in countries with high institutional quality, the freedom to do business becomes a tool for supporting sustainable economic development. The WLL has positive effects on SDGs in all quantiles except the 20th quantile. This result clearly shows the decisive role of women's labor rights and legal protections in driving sustainable development. The Granger causality test also supports these results: FR and WLL have a positive Granger causality effect on the SDGs. Additionally, while GDP positively affects SDGs in all quantiles, renewable energy efficiency negatively affects SDGs at low quantiles and has a positive impact at higher quantiles.
AtıfScopus13WoS11OpenAlex12
İncele - MakaleAçık Erişim2026Scopus SJRQ1Measuring Sustainability Under Uncertainty: Introducing Net ESG (N-ESG) Performance
Ongan, Serdar; Isik, Cem; Aydin, Rahman; Imamoglu, Ilyas Kays; Alvarado, Rafael; Ahmad, Munir
This study examines the reliability of environmental, social, and governance (ESG) scores in uncertain environments by introducing a new indicator, Net ESG (N-ESG), for the first time. This new index was calculated by subtracting a new ESG-based sustainability uncertainty index (ESGUI) from ESG scores. This study employed Pedroni (2004) and Westerlund (2007) tests, as well as the DOLS method, for 12 developed countries from 2002 to 2020. It analyzed the impact of economic, geopolitical, climate, and energy price-related uncertainties on both ESG and N-ESG through eight different models. Empirical findings indicate that a 1% change in CPU, GPR, EPU, and OPU indices increases ESG by 0.048, 0.355, 0.111, and 0.044 units, respectively, while the same rate of change decreases N-ESG by -6.501, -18.756, -8.972, and -8.193 units, respectively. These results can be interpreted as ESG scores may not fully reflect the true performance of companies in times of uncertainty, while N-ESG provides a more accurate representation of sustainability practices. These results suggest that policymakers should focus their sustainability policies not only on increasing ESG scores but also on preserving the true value of ESG by reducing uncertainty effects.
AtıfScopus36WoS36OpenAlex38İncele - MakaleAçık Erişim2026Scopus SJRQ1Does Climate Change Vulnerability Cause Energy Vulnerability in Sustainable Development?
Isik, Cem; Ongan, Serdar; Kuziboev, Bekhzod; Imamoglu, Ilyas Kays
Climate change and energy security are two fundamental vulnerability areas that interact with each other and hold critical importance for sustainable development goals. This research aims to fill the research gap by investigating the effects of climate change vulnerability (CCV) on the energy vulnerability (EV) relationship, which has not been adequately addressed in the literature, using a large panel dataset covering 74 countries and employing various methodological approaches (MMQR, PLFC, DID). The results of the MMQR model indicate that CCV increases EV across all quantiles. According to the results of the PLFC model, it is revealed that CCV on EV varies depending on the economic development level of countries. This effect is higher in low-income countries. The study also employs the DID model to examine the impact of China's foreign energy investments on countries' EV. According to this model, China's fossil-based energy investments, particularly those in the energy sector, increase the EV of countries. While economic development reduces EV across all quantiles, financial development reduces it in the lower and medium quantiles (25% and 50%); urbanization reduces it in the medium and higher quantiles (50% and 75%). All results show that the interaction between EV and CCV is a multidimensional and dynamic process. Accordingly, policymakers should develop integrated strategies that consider environment and energy policies, economic development, investment type, and environmental risks. Lastly, policymakers should consider energy investments from China not only as a tool for their country's economic growth, but also in terms of energy security and sustainability.
AtıfScopus22WoS22OpenAlex23İncele - MakaleYalnız künye2026Scopus SJRQ1Economic, Environmental, Social, and Governance (ECON - ESG) Strategies For Sustainable Development: Theory and a Holistic Evidence From Germany
Isik, Cem; Ongan, Serdar; Aydin, Rahman; Imamoglu, Ilyas kays
To achieve the SDGs, in addition to environmental (E), social (S), and governance (G) indicators, economic components should also be evaluated holistically. In this context, this research aims to test the time series characteristics of the indicators in the ECON-ESG structure, which is created by integrating the economic dimension into the ESG framework for Germany. For this purpose, linear and nonlinear structures, Fourier-based stationarity tests, and Bai-Perron multiple structural break tests were employed to examine the linear and nonlinear structures, stationarity cases, and structural breaks of various ESG and economic indicators (ECON). Findings show that many indicators are nonstationary, undergo structural changes over time, and exhibit nonlinear dynamics. The results indicate that sustainability policies should focus not only on indicator levels but also on the behavioral patterns and vulnerabilities of these indicators over time. In this regard, policymakers need to develop a holistic perspective on the economy and ESG, focusing on long-term and flexible policy designs. The study also offers important implications for how the ECON-ESG framework can serve as a model for both national and international markets, particularly in Germany, a developed and leading country in terms of sustainability. Therefore, the proposed ECON-ESG framework offers both theoretical and practical roadmaps for policymakers, firms, and investors to create long-term ESG strategies in support of the SDGs.
AtıfScopus74WoS75İncele - MakaleAçık Erişim2025Scopus SJRQ1The Role of Women's Entrepreneurship, Unemployment, Global Warming, and Technology in Sustainable Development: Evidence From OECD Countries
Isik, Cem; Ongan, Serdar; Günlü, Ebru; Aydin, Rahman; Imamoglu, Ilyas Kays
This study examines the effects of women's entrepreneurship, global warming, technological advancements, and unemployment on the achievement of the sustainable development goals (SDGs) across 38 OECD countries. Using country-specific panel causality methods, the analysis reveals significant asymmetries between developed and developing economies. Women's entrepreneurship (FEM) and technology (TEC) demonstrate stronger positive effects in developing countries such as Mexico, Slovakia, and Costa Rica, supporting SDGs 5 and 9. Global warming (SUR) negatively affects both groups, with notable impacts in Belgium, Mexico, and the UK, emphasizing the urgency of SDG 13. Unemployment (UNM) poses greater threats to sustainable development in emerging economies-particularly in Turkey and Latin American nations-while its influence remains limited in advanced countries. These results underscore the heterogeneous nature of SDG progress and suggest that universal, one-size-fits-all policies may fall short. Instead, national strategies should strengthen gender-inclusive entrepreneurship and innovation, while mitigating climate risks and labor market vulnerabilities. This paper presents a novel, multidimensional econometric framework and offers original insights into how interlinked economic, social, and environmental factors influence sustainability outcomes across diverse national contexts.
AtıfScopus23WoS18OpenAlex21İncele - MakaleAçık Erişim2025Scopus SJRQ3A Social Approach to Environmental Sustainability: The Nexus Well-Being, Tourism, Digitalization and Renewable Energy in Scandinavian Countries
Isik, Cem; Ongan, Serdar; Aydin, Buket; Aydin, Rahman; Imamoglu, Ilyas Kays
This research explores the impact of subjective well-being (SWB) on CO2 emissions in Scandinavian countries based on the need to analyze the effects of social indicators shaping environmental sustainability. The study aims to introduce the Welfare-Based SWB approach to the literature by expanding the classical Environmental Kuznets Curve (EKC) hypothesis with the social welfare dimension. SWB is considered in this study to be a social reflection and indirect measure of economic growth, which is the core determinant in the classical EKC hypothesis. The second-generation cointegration test, the Durbin-Hausman, and AMG long-term forecasting methods were used in this context. According to the empirical findings, SWB and digitalization increase carbon emissions, while tourism revenues and renewable energy consumption reduce emissions. The findings indicate that the classical EKC hypothesis is not confirmed and, similarly, an increase in social welfare (SWB) does not automatically lead to environmental improvement. Therefore, policymakers should develop social policies that will increase environmental sensitivity along with an increase in welfare.
AtıfScopus16WoS13OpenAlex16İncele - MakaleAçık Erişim2025Scopus SJRQ1Optimization of Ethanol Extraction Conditions From Sun-Dried Apricot and Prediction of Antioxidant, Phenolic, and Flavonoid Contents and Their Effects on HCT116 Cells Using Artificial Neural Networks
Topcu, Kubra Cinar; Gueven, Sara Altun; Cakir, Ozlem; Anlar, Pinar; Durul, Melekber Sulusoglu; Ay, Mizgin; Alyafei, Mohammed; Hayat, Faisal; Ercisli, Sezai
This study aimed to optimize the ethanol extraction conditions of sun-dried apricot (Prunus armeniaca L.) and evaluate the antioxidant capacity, phenolic, and flavonoid contents of the obtained extracts. Response surface methodology (RSM) was applied to determine the optimal extraction conditions, which were identified as 60 degrees C temperature, 34% ultrasonic power, 46 min sonication time, and a 4 g/mL solid-liquid ratio. Under these conditions, the extract exhibited a total phenolic content (TPC) of 4.20 mg GAE/g, a total flavonoid content (TFC) of 7.09 mg QE/g, a DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging capacity of 1.37 mg TE/g, a ferric reducing antioxidant power (FRAP) value of 9.12 mg TE/g, and a thiobarbituric acid reactive substances (TBARS) level of 1.69 mg MDA/g. The artificial neural network (ANN) model provided highly accurate predictions for these parameters. Additionally, cell culture experiments demonstrated that the extract exerted a dose-dependent cytotoxic effect on HCT116 colon cancer cells, significantly reducing their viability. These findings highlight the potential of sun-dried apricot extracts as natural antioxidants with possible applications in the functional food and pharmaceutical industries.
AtıfScopus2WoS2OpenAlex2
İncele - MakaleYalnız künye2025Scopus SJRQ1Tailoring the Electron Density of Functional Groups for Controlled Charge Transfer in SWCNTs
Fiebor, Alphonse; Cinar, Mehmet; Amsalem, Patrick; Achazi, Andreas J.; Gordeev, Georgy; Bartonitz, Florian; Xin, Fan; Koch, Norbert; Adeli, Mohsen; Paulus, Beate
Controlling the position of the Fermi level at the single-particle level in bulk amount of carbon nanotubes is a key technological bottleneck against their use in building nanodevices for electronics, optics, sensing, bioimaging, and beyond. Here are deployed a novel set of molecules built up from the same building blocks (aniline and methoxy groups attached on a triazine anchor) that efficiently p- and n-dope the nanotubes, depending upon the way they are assembled. Independent computational and experimental investigations consistently confirm the tunability-by-assembly concept of the charge transfer agents. The changes of the electronic density localized on the anchor groups and, upon attachment, the consistent variation of the position of the Fermi level in single-walled carbon nanotubes are monitored. The induced shifts reach several hundreds of meV, ranging from p-doping up to n-doping. This is evidenced by changes in the electronic and vibrational behavior of the nanotubes, as observed by Raman, photoelectron, and photoluminescence spectroscopies.
- Derleme MakaleAçık Erişim2023Scopus SJRQ1Natural products of relevance in the management of attention deficit hyperactivity disorder
Custódio, Luisa; Vizetto-Duarte, Catarina; Cebeci, Fatma; Özçelik, Beraat; Sharopov, Farukh; Gürer, Eda Sonmez; Kumar, Manoj; Iriti, Marcello; Sharifi-Rad, Javad; Calina, Daniela
Attention deficit hyperactivity disorder (ADHD) is among the most common neurodevelopmental disorders characterized by motor hyperactivity, attention deficit, distraction, impulsive behavior, and relationship difficulties. It affects children, and thus over the years, there has been growing attention on the use of natural product formulations and their naturally-occurring bioactive for overcoming the problem of ADHD. Concerning this issue, this review aims to discuss the ADHD treatment potential of natural products/formulations in vitro, in vivo as well as in clinical trials. To gather the most relevant data regarding bioactive compounds with potential therapeutic effects in the management of ADHD, the following databases were searched: PubMed/MedLine, ScienceDirect, and Google Scholar for articles in English. Various medicinal plants and their isolated biomolecules have been evaluated in vitro, in vivo, and in clinical trials for their ability to treat ADHD. Most of the analyzed research results showed an improvement of ADHD signs and symptoms in in vivo models, but the molecular mechanisms of action of the bioactive compounds are unclear and incompletely elucidated. Further studies are needed to determine the bioactive compound responsible for health-promoting effects in ADHD. In addition, clinical studies should be performed over longer periods with more participants.
AtıfScopus11WoS10OpenAlex11İncele - MakaleAçık Erişim2021Scopus SJRQ3Androsace azizsancarii sp. nov. (Primulaceae): a new species from northeastern Anatolia, Turkey
Sefali, Abdurrahman
Androsace azizsancarii (Primulaceae) is described and illustrated as a new species from Bayburt Province in northeastern Anatolia, Turkey. Diagnostic morphological characteristics, a full description and a distribution map are provided. The new species is morphologically closest to Androsace albana, A. multiscapa and A. villosa, but it is easily distinguished from these species by indumentum, leaf, flower and seed characters.
AtıfWoS6OpenAlex3İncele - MakaleYalnız künye2021Scopus SJRQ2Differential effects of inhibitors of PTZ-induced kindling on glutamate transporters and enzyme expression
Taspinar, Numan; Hacimuftuoglu, Ahmet; Butuner, Selcuk; Togar, Basak; Arslan, Gokhan; Taghizadehghalehjoughi, Ali; Okkay, Ufuk; Agar, Erdal; Stephens, Robert, Jr.; Turkez, Hasan
Epilepsy is a neurological disorder resulting from abnormal neuronal firing in the brain. Glutamate transporters and the glutamate-glutamine cycle play crucial roles in the development of seizures. In the present study, the correlation of epilepsy with glutamate transporters and enzymes was investigated. Herein, male Wistar rats were randomly allocated into four groups (six animals/group); 35 mg/kg pentylenetetrazole (PTZ) was used to induce a kindling model of epilepsy. Once the kindling model was established, animals were treated for 15 days with either valproic acid (VPA, 350 mg/kg) or ceftriaxone (CEF, 200 mg/kg) in addition to the control group receiving saline. After treatment, electrocorticography (ECoG) was performed to record the electrical activity of the cerebral cortex. The glutamate reuptake time (T-80) was also determined in situ using an in vivo voltammetry. The expression levels of glutamate transporters and enzymes in the M1 and CA3 areas of the brain were determined using a real-time polymerase chain reaction (RT-PCR). ECoG measurements showed that the mean spike number of the PTZ + VPA and PTZ + CEF groups was significantly lower (p < 0.05) than that of the PTZ group. Compared with the PTZ group, VPA or CEF treatment decreased the glutamate reuptake time (T-80). The expression levels of EAAC1, GLT-1, GLAST, glutamine synthetase (GS), and glutaminase were increased in the PTZ group. Treatment with VPA or CEF enhanced the expression levels of GLT-1, GLAST, EAAC1, and GS, whereas the glutaminase expression level was reduced. The current results suggest that VPA or CEF decreases seizure activity by increasing glutamate reuptake by upregulating GLT-1 and GLAST expression, implying a possible mechanism for treating epilepsy. Also, we have suggested a novel mechanism for the antiepileptic activity of VPA via decreasing glutaminase expression levels. To our knowledge, this is the first study to measure the glutamate reuptake time in situ during the seizure (i.e., real-time measurement).
AtıfScopus14WoS15OpenAlex16İncele - MakaleAçık Erişim2018Scopus SJRQ1Antimicrobial Carvacrol in Solution Blow-Spun Fish-Skin Gelatin Nanofibers
Liu, Fei; Saricaoglu, Furkan Tuerker; Avena-Bustillos, Roberto J.; Bridges, David F.; Takeoka, Gary R.; Wu, Vivian C. H.; Chiou, Bor-Sen; Wood, Delilah F.; McHugh, Tara H.; Zhong, Fang
Carvacrol is a volatile monoterpenic phenol and main component of oregano essential oil that shows nonspecific antimicrobial activity against foodborne pathogenic bacteria. Fish-skin gelatin (FSG) nanofibers encapsulating carvacrol (15%, 20%, 25%, and 30%, w/w FSG) were successfully prepared via solution blow-spinning (SBS) technique using lecithin (2.475% wb) as the surfactant. FSG emulsions with lower carvacrol ratios (5% and 10%) showed higher values in particle size and surface tension as well as lower values in viscosity and modulus, which led to failure of maintaining nanofibers shape. The formed carvacrol-FSG nanofibers showed round and smooth morphologies with average fiber diameters ranging from 103.2 to 138.1 nm as the carvacrol ratio increased from 15% to 30%. Carvacrol was evenly dispersed within the interior of nanofiber matrix. All carvacrol-FSG nanofibers showed inhibitive effects against the growth of Escherichia coli, Salmonella enterica, and Listeria monocytogenes. Moreover, nanofibers with lower carvacrol ratios showed bigger inhibition zones for E. coli and L. monocytogenes (20 mm compared with 12.5 mm for lowest to highest carvacrol ratios, respectively). Nanofibers stored at 20 degrees C (51% RH) showed better retention (40% to 60%) for carvacrol during the first 4 weeks of storage, while nanofibers stored at 2 degrees C (70% RH) showed better retention (10% to 30%) at the end of storage.
AtıfWoS28OpenAlex31İncele - MakaleAçık Erişim2013Scopus SJRQ1Effect of ultrasonic treatment on reduction of Esherichia coli ATCC 25922 and egg quality parameters in experimentally contaminated hens' shell eggs
Sert, Durmus; Aygun, Ali; Torlak, Emrah; Mercan, Emin
Backround: In this study, hen eggs which were experimentally contaminated with Esherichia coli ATCC 25922 were used. Contaminated eggs were washed statically (S5 to S30; 0 kHz) and by ultrasonic waves (U5 to U30; 35 kHz) for given applications of time (5, 15 and 30 min), then the eggs were stored at 22°C for 14 days. Results: Depending on the time of ultrasonic application, a significant increase in egg shell strength (P < 0.01) was recorded. The highest value of the Haugh unit (67.93, 1 day) was observed on the eggs which were washed by ultrasonic waves. Yolk width values of ultrasonic washed eggs diminished. E. coli was completely removed by 30 min of ultrasonic application. During storage E. coli growth was not detected on the eggs which were washed by ultrasonic waves except the eggs in U5 group (2.04 log CFU eggshell-1) on the first day of storage. Conclusion: Depending on the time of ultrasonic application a significant increase in egg quality parameters (shell strength, albumen height, Haugh units, and yolk height) were observed. The application of ultrasound led to a significant reduction in E. coli numbers on egg shells.
AtıfScopus21WoS20OpenAlex21İncele - DergiNORDIC JOURNAL OF BOTANY
- DergiMANAGERIAL AND DECISION ECONOMICS
- DergiEFOOD
- DergiCLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY
- DergiSUSTAINABLE DEVELOPMENT
- DergiBUSINESS STRATEGY AND THE ENVIRONMENT