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Koleksiyondaki öğeler
- MakaleYalnız künye2023Scopus SJRQ1Temporal Reflection Response of Plane Waves Within an N-Layer Structure Involving Bianisotropy
Hasar, Ugur C.; Ozturk, Gokhan; Kaya, Yunus; Barroso, Joaquim Jose; Ertugrul, Mehmet; Ramahi, Omar M.; Alfaqawi, Mona S. S.
The temporal reflection response of an N-layer composite structure involving bianisotropic behavior is examined for the first time in the literature. Toward this goal, the wave matrix (WM) method, which is fundamental, relatively easier to apply, and compact and iterative suitable for analysis of multilayer structures, is first extended to the analysis of an interface separating two different media involving bianisotropy. Next, the reflection response of the whole structure is derived in terms of series form to better analyze its temporal behavior. Then, frequency-domain and time-domain responses of the whole structure are expressed using a special reflection coefficient (the reduced reflection coefficient) by way of the concept of subregions. A numerical analysis is performed to demonstrate the applicability of our formalism for two different polarization types (perpendicular and parallel).
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İncele - MakaleAçık Erişim2020Scopus SJRQ1Isolation and Biophysical Characterisation of Bioactive Polysaccharides from Cucurbita Moschata (Butternut Squash)
Jiwani, Shahwar Imran; Gillis, Richard B.; Besong, David; Almutairi, Fahad; Erten, Tayyibe; Kök, M. Samil; Harding, Stephen E.; Paulsen, Berit S.; Adams, Gary G.
Cucurbits are plants that have been used frequently as functional foods. This study includes the extraction, isolation, and characterisation of the mesocarp polysaccharide ofCucurbita moschata. The polysaccharide component was purified by gel filtration into three fractions (NJBTF1, NJBTF2, and NJBTF3) of different molecular weights. Characterisation includes the hydrodynamic properties, identification of monosaccharide composition, and bioactivity. Sedimentation velocity also indicated the presence of small amounts of additional discrete higher molecular weight components even after fractionation. Sedimentation equilibrium revealed respective weight average molecular weights of 90, 31, and 19 kDa, with the higher fractions (NJBTF1 and NJBTF2) indicating a tendency to self-associate. Based on the limited amount of data (combinations of 3 sets of viscosity and sedimentation data corresponding to the 3 fractions), HYDFIT indicates an extended, semi-flexible coil conformation. Of all the fractions obtained, NJBTF1 showed the highest bioactivity. All fractions contained galacturonic acid and variable amounts of neutral sugars. To probe further, the extent of glycosidic linkages in NJBTF1 was estimated using gas chromatography-mass spectrometry (GCMS), yielding a high galacturonic acid content (for pectin polysaccharide) and the presence of fructans-the first evidence of fructans (levan) in the mesocarp. Our understanding of the size and structural flexibility together with the high bioactivity suggests that the polysaccharide obtained fromC. moschatahas the potential to be developed into a therapeutic agent.
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İncele - MakaleAçık Erişim2025Scopus SJRQ1Innovative governance for sustainable management of Mediterranean coastal aquifers: Evidence from Sustain-COAST living labs
Ceseracciu, Chiara; Nguyen, Thi Phuoc Lai; Deriu, Romina; Branca, Giampiero; Vozinaki, Anthi-Eirini K.; Karatzas, George P.; Mellah, Thouraya; Akrout, Hanene; Yildirim, Uemit; Kurt, Mehmet Ali
This study focuses on groundwater governance in Mediterranean socio-ecological systems, where anthropogenic and climate-related pressures lead to issues such as overexploitation, salinisation, and pollution, particularly in coastal areas. It provides empirical evidence of the practices and processes that foster governance learning and innovation towards adaptive and sustainable groundwater management, drawing on data from a comparative groundwater governance assessment of four case studies,each representing relevant issues within the mosaic of water challenges in the Mediterranean region. This study addresses several knowledge gaps by proposing a framework aligned with a socio-ecological systems approach, allowing for acomprehensive understanding of groundwater governance by consideringinterconnected social, economic, and environmental dimensions. The assessment process integrates diverse data and knowledge sources, and ensures the active participation of local stakeholders. The findings highlight several cross-cutting themes relevant to water governance innovation. These include transdisciplinary collaborations that recognise the multidimensionality of water governance, the role of cultural and social capital as catalysts for community mobilisation, the potential of community participation tools to promote voluntary behavioural changes, and the creation of social learning spaces to co-design scientifically robust and socially acceptable water management options. Furthermore, this study emphasises the integration of the Theory of Change to effectively engage stakeholders in the co-creation of tailored governance solutions, thereby enhancing the potential for sustainable policy outcomes.
AtıfScopus17WoS15OpenAlex13İncele - MakaleAçık Erişim2014Scopus SJRQ3Comparison of Levitation Forces of Bulk MgB2 Superconductors Produced by Nano Boron and Carbon-Doped Nano Boron
Duz, I.; Guner, S. B.; Erdem, O.; Demir, I.; Kapucu, V.; Çelik, S.; Ozturk, K.; Hossain, S.; Gencer, A.; Yanmaz, E.
MgB2 bulk superconductors were prepared by hot press plus furnace heating method. Two types of boron powders were used, one is amorphous nano boron and the other is C-doped boron. Characteristics of superconductors were determined by XRD and resistance measurements. Systematic levitation force measurements were performed by using a modular system at low temperatures. These bulk superconductors showed around 9 N repulsive and 4 N attractive forces in the z-axis at 20 K at closest point to the cryostat lid which contains the MgB2 superconductor. These values slightly decreased by increasing temperature to 24 and 28 K for both samples. Comparing two samples, nano boron MgB2 showed slightly higher levitation force than C-doped MgB2 although C-doped MgB2 has higher attractive force value at the closest point. This situation points out that C-doped MgB2 is much proper for attractive force applications (as guidance force) while the nanoboron MgB2 sample is much appropriate for repulsive force (as levitation).
AtıfScopus13WoS13OpenAlex17İncele - MakaleAçık Erişim2022Scopus SJRQ1Improved Method for Permittivity Determination of Dielectric Samples by Free-Space Measurements
Hasar, Ugur Cem; Kaya, Yunus; Ozturk, Hamdullah; Izginli, Mucahit; Ertugrul, Mehmet; Barroso, Joaquim Jose; Ramahi, Omar M.
A new deembedding technique is proposed for relative complex permittivity epsilon(r) determination of dielectric materials using gated free-space measurements. Its three main features are 1) it does not require any formal calibration procedure (calibration-free); 2) it is position-insensitive; and 3) it extracts ripple-free epsilon(r) due to gating process. The objective function derived to determine epsilon(r) by the proposed method is validated by free-space measurements of three dielectric samples (polypropylene, polyethylene, and polyoxymethylene). Besides, the accuracy of our method is compared with the accuracy of other calibrationfree and calibration-dependent methods in the literature.
AtıfScopus49WoS36OpenAlex44İncele - MakaleYalnız künye2025Scopus SJRQ1Sensitive Microwave Sensor for Detection and Quantification of Water in Adulterated Honey
Hasar, Hafize; Hasar, Ugur Cem; Kaya, Yunus; Ozturk, Hamdullah; Korkmaz, Huseyin; Yuzgulec, Kadir; Karaaslan, Muharrem; Ebrahimi, Amir; Nayyeri, Vahid; Ramahi, Omar M.
Honey is a rich source of sugar and is one of the indispensable ingredients in infant foods. Thus, it can be subjected to adulteration due to its cost. Measurement techniques such as liquid chromatography and near-infrared spectroscopy, used for detecting any adulteration, are expensive and need to be conducted by highly trained personnel for off-line analysis. Microwave measurements, as a fast, simple, and relatively inexpensive analysis, have recently shown great potential in detecting adulteration within honey samples. Nonetheless, sensor types used in such measurements are conventional. In this study, a reflection-type sensitive microwave sensor terminated by a metal back is proposed for the first time in the literature for the detection and quantification of water percentage ( delta ) level (mass-to-mass basis) within water-adulterated honey samples. When compared with other resonance-based microwave cavity sensors, thanks to its eight strips located at the centers of two closed circular loops, it demonstrates superior frequency selectivity and sensitivity ( S=5.13 %) validated by full-wave 3-D simulations performed by the CST Microwave Studio and equivalent circuit analysis carried out by the Advanced Design System (ADS) software. For example, for ethanol, the proposed sensor gives a frequency shift of more than 1 GHz in the X band. Resonance frequency shift and variation of the reflection coefficient amplitude ( |S11| ) are measured at X band to detect honey samples with up to 8% adulteration level. Three different honey samples (flower honey, highland honey, and thyme honey) were examined to test the performance and applicability of the proposed sensor.
AtıfScopus18WoS14OpenAlex17İncele - MakaleAçık Erişim2025Scopus SJRQ3Investigation of the relationship between apelin hormone response and some physiological parameters in enzootic bovine leukosis virus infected cattle
Sait, A.; Bayraktar, B.; Korkmaz, S.; Genç, M.; Bayraktar, S.; Kotan, G. C.; Aydemir, S.; Takma, C.; Bülbül, A. S.; Aksakal, V
Apelin is a hormone with lymphangiogenesis potential, associated with tumor growth and lymph node metastasis, and is reported to stimulate tumor vascularization. This study aimed to investigate the response of the apelin hormone in cattle with and without Enzootic Bovine Leukosis (EBL) infection, based on physiological parameters such as breed, age, and body condition score (BCS). A total of 120 Simmental and Montafon cattle of varying ages (<2, 2-8, and >8) and BCS categories (<2, 3-3.5, and >= 4) were included in the study. Serum apelin hormone levels were measured using the ELISA technique in blood samples collected from the neck vein ( Vena jugularis) of the animals. The analysis of mean serum apelin (ng/mL) values revealed that, among EBL-positive cattle, the highest value was 2.77 ng/mL in Simmental cattle aged 2-8 years with a BCS of 3-3.5, while a value of 2.69 ng/mL was observed in Montafon cattle aged >8 years with a BCS of 3-3.5. For EBL-negative cattle, the highest mean serum apelin value was 2.24 ng/mL, recorded in Simmental cattle aged 2-8 years with a BCS of 3-3.5, whereas it was 1.45 ng/mL in Montafon cattle aged >8 years with the same BCS. In conclusion, this study demonstrated for the first time the effect of apelin hormone levels in cattle with or without EBL, depending on physiological parameters such as age, breed, and BCS. It is suggested that the apelin hormone, which is involved in neoplastic lymphocyte cell infiltration in the lymphoreticular tissues of cattle, and plays a role in regulating tumor growth in EBL, a malignant tumor disease, may contribute to eradication programs. Moreover, the evaluated parameters may prove valuable for disease prevention and control strategies.
AtıfScopus1WoS1OpenAlex1İncele - MakaleAçık Erişim2022Scopus SJRQ1Determination of Propagation Constants and Wave Impedance of Non-Reciprocal Networks From Position-Insensitive Waveguide Measurements
Hasar, Ugur C.; Kaya, Yunus; Izginli, Mucahit; Ozturk, Hamdullah; Barroso, Joaquim J.; Ramahi, Omar M.; Ertugrul, Mehmet
A microwave method is proposed to determine the forward and backward propagation constants (gamma ⁺ and gamma ⁻) and the wave impedance ( z_w ) of reciprocal and non-reciprocal microwave networks whose positions are not known within their measurement cells (position-insensitive). The proposed method relies purely on analytical expressions and can also evaluate the reference plane transformation distances. Scattering parameter measurements at the X-band (8.2-12.4 GHz) of a reciprocal network (a waveguide straight) and a non-reciprocal network (a microwave phase shifter) arbitrarily positioned into their measurement cells were conducted to retrieve gamma ⁺, gamma ⁻, and z_w for validation of our method and testing its position-insensitive property. The importance of the method becomes apparent when compared to conventional methods whose accuracy is based on precise determination of the reference planes.
AtıfScopus9WoS9OpenAlex9İncele - Derleme MakaleAçık Erişim2024Scopus SJRQ1High pressure homogenization for preservation of liquid foods-Mechanisms, molecular modifications and recent developments
Pandiselvam, R.; Özaslan, Zeynep Tugba; Sahni, Prashant; Khanashyam, Anandu Chandra; Kutlu, Naciye; Yilmaz, Merve Silanur; Isleroglu, Hilal; Ramniwas, Seema; Rustagi, Sarvesh
High Pressure Homogenization (HPH) is emerging as a cutting-edge, non-thermal technology for liquid food preservation, offering significant advantages over conventional methods. Recent advances in HPH technology, particularly with the development of robust valves capable of withstanding pressures of 350-400 MPa, have opened new possibilities for the food industry. HPH not only extends the shelf life of liquid foods but also preserves nutritional value, improves homogeneity, reduces energy consumption, and minimizes the need for chemical preservatives. Its ability to inactivate microorganisms and enzymes while modifying bioactive components is particularly valuable for enhancing food safety and nutritional quality. Novel aspects of HPH include its efficiency in microbial and enzyme inactivation through cellular disruption, demonstrated in both lab and industrial settings, as well as its capacity to alter the functional properties of proteins, carbohydrates, and lipids. This results in improved stability, viscosity, and shelf life of various products. The versatility of HPH enables the development of novel food formulations that meet evolving consumer demands for safer, more nutritious options. This review critically examines the literature on HPH's application in liquid foods, focusing on its impact on enzymatic activity and bioactive components, while highlighting the parameters that influence microbial inactivation during HPH processing. The ongoing technological advancements in HPH present a promising future for revolutionizing food preservation practices.
AtıfScopus17WoS13OpenAlex21İncele - MakaleAçık Erişim2026Scopus SJRQ2Comprehensive characterization of 26 Turkish asteraceae species: Insights from FTIR, phytochemical composition, and elemental analysis via ICP-MS
Civas, Ayse; Karakas, Seydanur; Bayrak, Burak; Akyüz, Beyzanur; Keçeci, Emire Bengisu; Özerd, Elif Beyza; Sönmez, Hatice Rumeysa; Asgarli, Tugay; Disli, Fatma Taeb; Yuca, Hafize
This study provides a comprehensive phytochemical, elemental, and spectroscopic characterization of 26 species belonging to the Asteraceae family, several of which are endemic to T & uuml;rkiye and traditionally used in folk medicine. Qualitative screening revealed the widespread presence of flavonoids, saponins, tannins, and carbohydrates, while alkaloids and anthracene heterosides were entirely absent in all taxa. Among the species analyzed, Cichorium intybus, Cyanus depressus, Achillea arabica, and Cirsium davisianum exhibited the richest phytochemical diversity, suggesting strong biological potential. Quantitative evaluation showed that Klasea serratuloides possessed the highest total phenolic content (99.49 mu g GAE/mg extract), followed by Artemisia scoparia and Inula sarana, indicating notable antioxidant potential. Elemental analysis by ICP-MS demonstrated significant interspecies variation, with Centaurea armena, Centaurea arvensis, and Cichorium intybus containing elevated levels of essential macro- and trace elements such as K, Mg, Ca, Zn, and Se, whereas Helichrysum plicatum and Scorzonera ulrichii showed high Co and Se contents. Conversely, trace levels of potentially toxic elements (e.g., Al, U) were detected in some taxa, emphasizing the need for careful evaluation of their pharmacological use. FTIR analysis confirmed the presence of functional groups characteristic of phenolics, flavonoids, tannins, coumarins, and cardioactive heterosides, as indicated by distinct O-H (3200-3600 cm-1), C-H (2850-2950 cm-1), and C=O (1700-1650 cm-1) stretching bands. The combined interpretation of phytochemical and FTIR data underscores the chemical diversity and functional group complexity of these plant extracts. Overall, the results highlight the nutritional and pharmacognostic significance of several Asteraceae species, supporting their potential application in antioxidant, nutraceutical, and therapeutic formulations.
AtıfScopus2WoS2OpenAlex4İncele - MakaleYalnız künye2022Scopus SJRQ1Complex Permittivity and Thickness Evaluation of Low-Loss Dielectrics From Uncalibrated Free-Space Time-Domain Measurements
Hasar, Ugur Cem; Kaya, Yunus; Ozturk, Hamdullah; Izginli, Mucahit; Barroso, Joaquim Jose; Ramahi, Omar M.; Ertugrul, Mehmet
A free-space time-domain method is proposed to retrieve dielectric constant (epsilon r), conductivity (sigma e), and thickness (d) of metal-backed low-loss dielectric samples using calibration-independent reflected power peak measurements. Its algorithm is validated by numerical calculations and simulations (CST Microwave Studio) using a sine-modulated Gaussian window. A sensitivity analysis is followed to examine its performance considering the dependencies of reflected power peaks with respect to epsilon r and sigma e. Free-space time-domain measurements have been implemented after transforming frequency-domain measurements into time-domain ones to extract epsilon r, sigma e, and d of polypropylene, polyethylene, and polyoxymethylene samples.
AtıfScopus48WoS42OpenAlex43İncele - MakaleAçık Erişim2026Scopus SJRQ3Ramadan intermittent fasting alters cardiac autonomic modulation, neuromuscular performance, and recovery in adolescent tennis players: a within-subject repeated-measures design
Lakhdar, Nadia; Landolsi, Mounir; Ghouili, Hatem; Ceylan, Halil Ibrahim; Ceylan, Nagihan Burcak; Muntean, Raul Ioan; Alsaeed, Mohammed Issa; Ben Said, Noureddine M.; Zaouali, Monia; Bouhlel, Ezzedine
Background: Tennis requires repeated high-intensity efforts with brief recovery periods, placing significant demands on cardiac autonomic regulation and neuromuscular performance. Ramadan intermittent fasting alters sleep, nutrition, and hydration patterns, potentially affecting match responses, particularly in adolescents. Methods: Sixteen male International Tennis Federation (ITF) junior players completed a within-subject repeated-measures study during mid-Ramadan and 15 days post-Ramadan. Each performed a standardized two-set outdoor match under both conditions. Heart rate variability (HRV), countermovement jump (CMJ), blood glucose, hydration markers, and rating of perceived exertion were assessed at baseline (T0), between sets (T1), and post-match (T2). Sleepiness, chronotype, fatigue, and recovery were evaluated via validated questionnaires. Results: Match play reduced lnRMSSD (p < 0.001, eta p(2 )= 0.775) and increased LF/HF (p < 0.001, eta p(2)= 0.234), indicating sympathetic dominance. During Ramadan, parasympathetic activity was lower (p < 0.001, eta p(2)= 0.269), and CMJ performance was reduced (p = 0.010, eta p(2)= 0.085). Blood glucose showed a Period & times; Set interaction (p = 0.020,eta p(2) = 0.114). Sleepiness, fatigue, and perceived recovery were significantly impaired (p < 0.001). Conclusion: Ramadan intermittent fasting reduces vagal activity and impairs neuromuscular performance in adolescent tennis players. HRV-guided training, optimized nutrition, and sleep management may help mitigate these effects.
- MakaleAçık Erişim2021Scopus SJRQ3Development of SiO2 based doped with LiF, Cr2O3, CoO4 and B2O3 glasses for gamma and fast neutron shielding
Aygün, Bunyamin; Sakar, Erdem; Karabulut, Abdulhalik; Alim, Bunyamin; Sayyed, Mohammed, I; Singh, Vishwanath P.; Yorgun, Nergiz Yildiz; Özpolat, Ozgur Firat
In this study, the fast neutron and gamma-ray absorption capacities of the new glasses have been investigated, which are obtained by doping CoO,CdWO4,Bi2O3, Cr2O3, ZnO, LiF,B2O3 and PbO compounds to SiO2 based glasses. GEANT4 and FLUKA Monte Carlo simulation codes have been used in the planning of the samples. The glasses were produced using a well-known melt-quenching technique. The effective neutron removal cross-sections, mean free paths, half-value layer, and transmission numbers of the fabricated glasses have been calculated through both GEANT4 and FLUKA Monte Carlo simulation codes. Experimental neutron absorbed dose measurements have been carried out. It was found that GS4 glass has the best neutron protection capacity among the produced glasses. In addition to neutron shielding properties, the gamma-ray attenuation capacities, were calculated using newly developed Phy-X/PSD software. The gamma-ray shielding properties of GS1 and GS2 are found to be equivalent to Pb-based glass.
AtıfScopus19WoS19OpenAlex16İncele - MakaleYayıncıda açık erişim2023Scopus SJRQ3Investigation of endocrine response of thyroid and intestinal and adipose tissues due to the addition of Moringa oleifera essential oil in diet for quails exposed to heat stress
Bayraktar, Bulent; Tekce, Emre; Bayraktar, Sevil; Böyük, Gulbahar; Takma, Cigdem; Aksakal, Vecihi; Genç, Murat; Kaya, Hacer; Ülker, Ufuk; Gürbüz, Ahmet Burak
-In this study, we aimed to determine the effect of Moringa oleifera essential oil (MOEO) supplementation to rations of Japanese quail (Coturnix coturnix japonica) grown under heat stress (HS) on some adipokine (visfatin, adiponectin, and chemerin), intestinal (citrulline), 3,5,3 '-triiodothyronine (T3), thyroxine (T4), and thyroid-stimulation hormone (TSH) levels in the serum. For this purpose, 320 day-old male quail chicks were used. The study was conducted over 42 days, including a 7-d adaptation period and a 35-d experimental period. Eight trial groups were established, each including 10 quail: CT (control temperature, 25 celcius), MOEO 200, MOEO 400, MOEO 600, HSC (HS control), SMOEO 200, SMOEO 400, and SMOEO 600. Based on the results, a dose-dependent decrease was observed on days 21 and 42 in serum adiponectin and T3 in the stress and stress-free groups compared with the control group due to MOEO supplementation. The lowest decrease was observed in the MOEO 600 mg/kg dose group. In addition, an increase in stressed groups was observed when examining serum citrulline levels, while chemerin levels did not have a statistically significant effect. While the decrease in serum visfatin, T4, and TSH levels on the 21st day did not have a statistically significant effect, a significant effect was determined on the 42nd day. The addition of MOEO at 600 mg/kg to the ration may be beneficial in preventing intestinal damage and inflammation that may occur due to HS.
AtıfScopus14WoS15OpenAlex19İncele - MakaleYalnız künye2020Scopus SJRQ2Theoretical and experimental validation gamma shielding properties of B2O3-ZnO-MgO-Bi2O3 glass system
Kaky, Kawa M.; Sayyed, M. I.; Khammas, Abbas; Kumar, Ashok; Sakar, Erdem; Abdalsalam, Alyaa H.; Sakar, Betul Ceviz; Alim, Bunyamin; Mhareb, M. H. A.
In the present work, we fabricated a series of six glasses to be utilized in the field of radiation shielding application. Glasses have been synthesized using a melt-quenching ordinary technique. In this work, we investigated the structural properties of these glasses using Raman spectroscopy. Moreover, optical properties have been studied in the present work. The radiation attenuation ability for the present samples was also investigated and measured using transmission geometry between 81 and 964.1 keV. The mass attenuation coefficient was measured and the results were validated by the WinXcom program. Also, radiation protection efficiency (RPE) was evaluated and discussed in terms of photon energy and Bi2O3 concentration. From RPE curve, we found that the fabricated glasses can be used as effective shielding materials especially for the low energies (81-383 keV). The half value layer also was calculated and the results of this parameter showed that S6 (contains 60 mol% of Bi2O3) has the higher probability of the interaction with gamma photons, leading to less number of photons transmitted this sample and thus better photon attenuator.
AtıfScopus69WoS72OpenAlex76İncele - MakaleAçık Erişim2026Scopus SJRQ1Acute Caffeine Ingestion, Calendar-Based Menstrual-Cycle Window, Time of Day, and Match-Induced Fatigue Independently and Interactively Influence Psychophysiological, Cognitive, and Physical Performance in Elite Female Volleyball Players: A Randomized Double-Blind Placebo-Controlled Crossover Design Study
Seddik, Meher; Dhahbi, Wissem; Bessifi, Manel; Moussa-Chamari, Imen; Ceylan, Halil Ibrahim; Ceylan, Nagihan Burcak; Muntean, Raul Ioan; Cular, Drazen; Souissi, Nizar
Aim: Female athletic performance is shaped by the convergence of menstrual-cycle timing, circadian rhythms, fatigue, and ergogenic supplementation; yet no prior study has examined these factors simultaneously in a sport-specific setting. This study investigated the independent and combined effects of acute caffeine ingestion, calendar-based testing window, time of day, and match-induced fatigue on psychophysiological, cognitive, and physical performance in trained female volleyball players. Methods: Thirteen elite eumenorrheic female volleyball players (age: 24.23 +/- 4.06 years) completed a randomized, double-blind, placebo-controlled crossover protocol comprising 12 sessions corresponding to all combinations of testing window (menstrual, follicular, luteal), supplementation (caffeine 6 mg & centerdot;kg(-1) vs. placebo), and time of day (08:00 h vs. 18:00 h). Assessments included the Epworth Sleepiness Scale, Pittsburgh Sleep Quality Index, Spiegel questionnaire, Profile of Mood States, Hooper Index, Stroop task, Countermovement Jump (CMJ), Modified Agility T-Test (MAT), and Reactive Agility Test (RAT), administered before and after a one-hour simulated match. Results: Significant main effects of testing window, caffeine, time of day, and fatigue state were observed across all outcome domains (all p < 0.05). Caffeine reduced daytime sleepiness (F(1,12) = 23.84, p < 0.001, eta p(2) = 0.665), enhanced vigor (F(1,12) = 114.10, p < 0.001, eta p(2) = 0.905), and improved MAT performance (F(1,12) = 33.27, p < 0.001, eta p(2) = 0.735). The follicular window was associated with superior cognitive, neuromuscular, and mood-related outcomes relative to the menstrual and luteal windows. Exploratory higher-order interactions suggested condition-specific caffeine benefits for MAT, RAT, and CMJ, particularly in afternoon post-fatigue conditions; these patterns require replication in larger samples. Conclusions: Acute caffeine ingestion improved several psychophysiological, cognitive, and neuromuscular outcomes in trained female volleyball players, with effects that varied across calendar-based testing windows, time of day, and fatigue state. Individualized supplementation strategies incorporating cycle timing and circadian context remain investigational; prescriptive recommendations require replication in larger, hormonally verified samples before clinical or applied adoption.
AtıfScopus1WoS1OpenAlex2İncele - MakaleYalnız künye2026Scopus SJRQ2The moderating effects of geopolitical risks on sustainable development through economic complexity and renewable energy consumption in 25 oil-producing countries
Ongan, Serdar; Özdemir, Dilek; Imamoglu, Ilyas Kays; Isik, Cem
Conflicts in controlling or using natural resources, arising from geopolitical risks (GPR), which have become a new normal today, can damage natural ecosystems and threaten sustainable development. In this context, GPR can turn the positive impact of supporting independent variables on sustainable development (SD) into a negative one. This research investigates the moderating effects of GPR on SD through renewable energy consumption (REN) and economic complexity (EC) in 25 oil-producing countries with relatively higher oil-reserve-related risks between 2000 and 2021. The panel quantile regression analysis reveals. (i) While using REN individually improves SD in countries with high SD (in the 80th and 90th quantiles), this improving effect turns to a worsening effect due to its interaction with GPR, which shows the moderating impact of GPR. (ii): While EC individually improves SD across all quantiles, these improving effects persist in countries with low SD (in the 10th, 20th, 30th, and 40th quantiles) even when complexity interacts with GPR, showing that GPR has no moderating impact on SD. Therefore, policymakers should investigate why the interaction of REN with GPR worsens SD in highly sustainable countries and redevelop regulatory renewable energy policies accordingly.
- MakaleAçık Erişim2022Scopus SJRQ2Synthesis and in Vitro Toxicity Assessment of Different Nano-Calcium Phosphate Nanoparticles
Togar, Basak; Türkez, Hasan; Bakan, Feray; Arslan, Mehmet Enes; Tatar, Abdulgani; Cacciatore, Ivana; Hacimüftüoglu, Ahmet; Çadirci, Kenan; Stefano, Di Antonio; Mardinoglu, Adil
Nanoscale biomaterials are commonly used in a wide range of biomedical applications such as bone graft substitutes, gene delivery systems, and biologically active agents. On the other hand, the cytotoxic potential of these particles hasn't yet been studied comprehensively to understand whether or not they exert any negative impact on the cellular structures. Here, we undertook the synthesis of beta-tricalcium phosphate (beta-TCP) and biphasic tricalcium phosphate (BCP) nanoparticles (NPs) and determine their concentration-dependent toxic effects in human fetal osteoblastic (hFOB 1.19) cell line. Firstly, BCP and beta-TCP were synthesized using a water-based precipitation technique and characterized by X-Ray Diffraction (XRD), Raman Spectroscopy, and Transmission Electron Microscopy (TEM). The cytological effects of beta-TCP and BCP at different concentrations (0-640 ppm) were evaluated by using 3- (4,5-dimethylthiazol-2-yl) -2,5-diphenyltetrazolium bromide (MTT) and lactate dehydrogenase (LDH) assays. The total oxidative status (TOS) parameter was used for investigating oxidative stress potentials of the NPs. In addition, the study assessed the DNA damage product 8-hydroxy-2'-deoxyguanosine (8-Oxo-dG) level in hFOB 1.19 cell cultures. The results indicated that the beta-TCP (above 320 ppm) and BCP (above 80 ppm) NPs exhibited cytotoxicity effects on high concentrations. It was also observed that the oxidative stress increased relatively as the concentrations of NPs increased, aligning with the cytotoxicity results. However, the NPs concentrations of 160 ppm and above increased the level of 8-OH-dG. Consequently, there is a need for more systematic in vivo and in vitro approaches to the toxic effects of both nanoparticles.
AtıfScopus4WoS1OpenAlex3İncele - 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.
AtıfScopus2WoS2OpenAlex2İncele - Derleme MakaleAçık Erişim2021Scopus SJRQ1A review on developments of environmentally friendly geopolymer technology
Krishna, R. S.; Mishra, Jyotirmoy; Zribi, Marwa; Adeniyi, Funmilayo; Saha, Suman; Baklouti, Samir; Shaikh, Faiz Uddin Ahmed; Gökçe, H. S.
This study aims to present an overview of the progress of geopolymer composites with regards to the latest developments on its constituents (binders, activators, and aggregates) and manufacturing techniques. Some ecological, economic, and industrial limitations of the traditional aluminosilicate binders yield to the pursuit of alternative ones over the period. Some of these latest binders e.g. ferrochrome ash, mine tailings, rice husk ash, red mud, have been highlighted in this paper. Current advances on replacement of natural fine and coarse aggregates such as mine tailings (iron ore tailings), recycled/lightweight aggregates for geopolymer preparation have been reviewed from the past literature. The paper also focuses on developments regarding the new class of green alkaline and acidic activators, which is traditionally considered to be the binding agent in the preparation of geopolymer composites. Different geopolymer production methods have been briefly discussed to study their effectiveness in achieving a strong and durable composite. This paper may serve to encourage further experimental research works for achieving more sustainable, cost-effective geopolymer composites with enhanced mechanical properties.
AtıfScopus89WoS77OpenAlex88İncele
