Sürdürülebilir Kalkınma Amaçları

Yazarlar

  • MakaleAçık Erişim2026Scopus SJRQ1
    Determination of complex permittivity of a thin low-loss dielectric sample using state-space approach from waveguide measurements

    Hasar, Ugur C.; Ali, Husain; Kaya, Yunus

    An extraction procedure is proposed for relative complex permittivity () determination of thin low-loss samples positioned/deposited on a supporting substrate material using waveguide non-resonant microwave measurements. Its substrate thickness and sample thickness independence makes it unique extraction method in comparison with the available retrieval methods which are free from either substrate thickness information only or sample thickness information only. Its theoretical model is constructed on the state-transition matrix and state vector through which the link between and measured scattering (S-) parameters is established. Compared with previous works in the literature, a closed form (explicit) expression of is derived for a two-layer (sample on a substrate material) composite structure, thereby eliminating any numerical analysis or tool. Numerical analyses are implemented for validation of the proposed method as well as assessing the effect of noise and any possible air gap between the sample and its substrate. X-band ( GHz) waveguide measurements of a thinner (around 1.00 mm) polyvinyl chloride (PVC) for different measurement scenarios and measurements of a thin zinc oxide film (m) were performed to evaluate the performance of the proposed extraction method against other similar methods in the literature. Our method can find applications for characterization of thin-film, radar-absorbent material coatings, anti-corrosive paints, or thermal barrier coatings where sample thickness (and substrate thickness) can vary from one sample to another from the same batch.

  • MakaleAçık Erişim2026Scopus SJRQ1
    Adverse childhood experiences and problematic gambling among young adults: a moderated serial mediation analysis

    Yayla, İbrahim Erdoğan; Makas, Samet; Dombak, Kübra; Bekir, Seyhan; Çelik, Eyüp; Arpaci, Ibrahim; Baloglu, Mustafa

    Problem gambling is a serious public health issue among young adults today and the literature suggests that adverse childhood experiences may be associated with it. Additionally, difficulties in emotion regulation and self-control may contribute to the association between problem gambling and adverse childhood experiences. Sensation seeking and a family history of gambling may also influence these relationships. Hence, we examined the relationship between adverse childhood experiences and problem gambling among young adults. We analyzed the collected data from 579 young adults (18–29 years old, 67.5% male) via an online survey using a cross-sectional research design. More specifically, we tested the serial mediating roles of difficulties in emotion regulation and self-control, as well as the moderating roles of sensation seeking and a family history of gambling. We found a significant positive association between adverse childhood experiences and problem gambling. Both difficulties in emotion regulation and self-control had significant mediating effects. Sensation seeking and family history of gambling moderated the mediating effects, strengthening the pathways leading to problem gambling at higher levels of sensation seeking and in the presence of family gambling history. These findings indicate that emotion regulation and self-control are important psychological processes in explaining the relationship between adverse childhood experiences and problem gambling. They also suggest that high sensation seeking and a family history of gambling may strengthen the relationships.

    • SDG 3 · Sağlık ve Kaliteli Yaşam
    • SDG 16 · Barış, Adalet ve Güçlü Kurumlar
  • MakaleAçık Erişim2026Scopus SJRQ1
    Performance level controlled efficiency of graphene nanoplatelets in cementitious composites

    Şahin, Yaren; Öksüzer, Nurullah; Kütük, Sezai; Gökçe, Hacı Süleyman

    Graphene nanoplatelets (nGP) have been widely reported as effective nano-reinforcements for cementitious composites; however, their optimal dosage remains inconsistent across existing studies. This variability is commonly attributed to nanomaterial-related parameters, whereas the influence of the cementitious matrix’s inherent performance is rarely systematically examined. In this study, cementitious matrices with distinct performance levels were designed by varying water-to-binder ratios (0.55, 0.40, and 0.30) and incorporating silica fume. Their interaction with nGP was experimentally investigated, with contents up to 2.4% being used. A total of 25 mix designs were evaluated for fresh-state behavior, mechanical performance, transport properties, and microstructural characteristics. The results indicate that the efficiency and optimal utilization of nGP are strongly governed by the matrix performance level. High-performance matrices (water-to-binder (w/b) = 0.30, 11% silica fume) achieved peak performance at 1.2% nGP, yielding compressive strength of 118.2 MPa and up to 50% reduction in capillary water transport, whereas low-performance matrices (w/b = 0.55) exhibited limited sensitivity to nGP incorporation. Microstructural observations confirmed that matrix densification improved nGP integration and hierarchical pore refinement by enhancing interfacial bonding, thereby restricting capillary water transport. The findings demonstrate that optimal nGP dosage cannot be treated as an intrinsic material parameter and should instead be defined in relation to matrix performance level, enabling performance-based dosage guidelines for nano-engineered composites in high-durability applications.

    • SDG 9 · Sanayi, Yenilikçilik ve Altyapı
    AtıfWoS1OpenAlex1
    ScopusWeb of SciencePubMedİncele
  • MakaleAçık Erişim2026Scopus SJRQ1
    Permittivity extraction of sandy soils through uncalibrated and thickness-independent meniscus-free measurements using a hollow coaxial line

    Hasar, Ugur C.; Korkmaz, Huseyin; Kaya, Yunus

    Measurement techniques for accurate moisture level determination of various soil conditions are becoming popular in recent studies. Microwave-driven techniques, as positioned into indirect methods, could be tailored for precise and real-time detection of soil moisture. However, improper implementation of calibration techniques or usage of imperfect calibration standards required for precise measurements by these techniques presents a challenging limitation for their widespread usage. Besides, meniscus formation on top of soil samples with a sufficient moisture level could adversely influence the performance of these techniques. In this study, we present a microwave extraction method for eliminating the requirement of a formal calibration procedure and additionally removing the effect of meniscus on measurements through relative measurements of sandy soil samples while maintaining accurate permittivity extraction with no information of sample thickness. To achieve our goal, a mathematical framework unifying wave-cascading matrix and state-transition matrix presentations is proposed for permittivity determination from three measurement configurations (empty line, the (sandy) soil sample sandwiched between two identical plugs, and a shifted version of this plug-sample-plug configuration) and their inverses implemented by port switching operation. The proposed method is first validated by permittivity measurements of two liquid samples (distilled water and methanol). Then, permittivity measurements of two sandy soil samples (having more than 90% sand content) were conducted using Type-N-to-EIA 1-5/8” coaxial lines (with no universal calibration standard) over 0.05 GHz–3.0 GHz. From these measurements, it is noted that our meniscus-free method determines permittivity with a maximum absolute difference of 3.4% (evaluated from five independent measurements) while another similar method, suffering from meniscus presence, extracts permittivity with a maximum absolute difference of 4.0%. This indicates a clear advantage of our method for measurements of sandy soil samples having meniscus formation. We then utilized to construct a calibration curve, compared with other calibration curves using by other methods, allowing prediction of moisture volume content () of the tested sandy soil samples from measured permittivity data whose conformity analysis implemented by the three-pole Debye model and the Mironov-Fomin model. It is observed that this calibration curve could be utilized to predict within margin from measured permittivity data.

  • MakaleAçık Erişim2025Scopus SJRQ1
    Investigation of endocrine and cerebral response and nutrition and physical performance parameters according to bigorexia nervosa levels: a cross-sectional study in sports sciences faculty students

    Erkılıç, Ali Ozan; Bayraktar, Bülent; Erkiliç, Tuğçe Orkun; Türkmen, Mutlu; Kul, Murat; Yönal, Mehmet

    The aim of this study is to investigate the effects of Bigorexia nervosa (BGN) levels on endocrine (Asprosin, GLP-1) and cerebral (BDNF) responses and nutritional and physical (6MWT, Six-Minute Walk Test)), speed, metabolic equivalent unit (MET)) performance parameters in students of the faculty of sports sciences. This study investigated muscle dysmorphic disorder (MDD), physical activity levels, and specific hormonal markers in 120 university students (63 females, 57 males) aged 18–25 years, all studying sport sciences and reporting no existing health problems. Participants completed a demographic questionnaire, food frequency questionnaire and the Muscle Dysmorphic Disorder (Bigorexia) Inventory through face-to-face interviews. Physical activity was assessed using the 6-Minute Walk Test (6MWT) to measure walking distance, and Metabolic Equivalent (MET) was calculated based on the American College of Sports Medicine (ACSM) formula. Body Mass Index (BMI) was determined from anthropometric measurements of height and body weight. Saliva samples were collected to analyze Asprosin, BDNF, and GLP-1 hormone levels using the ELISA technique.Data were analyzed using number, percentage, mean, chi-square, t-test, Pearson correlation, and ANOVA tests. In all analyses, significance was accepted as p < 0.05. According to the demographic findings of the study, the majority of participants (64.2%) were third-year students, and 52.5% were female. The mean age of the participants was 22.01 years, the mean height was 168.59 cm, and the mean weight was 62.61 kg. 73.3% of the individuals were classified as normal weight, 12.5% as pre-obese, 11.7% as underweight, and 2.5% as obese. Men had significantly higher bigorexia and its subscale scores than women (p < 0.05), and bigorexia was positively correlated with height and negatively correlated with BMI (p < 0.01). Mean salivary BDNF levels were higher in participants consuming 1–2 meals per day (p = 0.035), and mean salivary asprosin levels were significantly higher in the obese group compared to the healthy group (p = 0.008). Additionally, a strong positive correlation was found between asprosin and GLP1 levels (r = 0.585; p < 0.01). Bigorexia status was significantly associated with meat, meat products, and fat consumption (p < 0.05), while no association was found with physical performance parameters such as 6MWT, speed, and MET (p > 0.05). The average MET value was found to be 4.53, indicating that participants generally engaged in moderate-intensity physical activity. In conclusion, examining endocrine (asprosin, GLP-1) and cerebral (BDNF) hormone responses, as well as nutritional and physical performance parameters, according to BGN levels reveals the impact of BGN on physiological and nutritional behaviors. Given the impact of BGN trends on students’ health, examining hormone profiles and their relationships with physical performance and nutrition is believed to significantly contribute to understanding the health problems associated with BGN and developing appropriate interventions.

    • SDG 3 · Sağlık ve Kaliteli Yaşam
  • MakaleAçık Erişim2025Scopus SJRQ1
    Characterization and immune-modulatory roles of branched glucan and acetylated gluco-oligosaccharides produced by glucansucrase 40 from Leuconostoc mesenteroides YTU 40

    Dere, Sevda; İspirli, Hümeyra; Korkmaz, Kader; Tuncil, Yunus Emre; Sagdic, Osman; Narbad, Arjan; Ayyash, Mutamed; Dertli, Enes

    Glucansucrases (GS) are functional enzymes for the production of distinct glucan and gluco-oligosaccharide structures with potential bioactive characteristics. In this study, an active glucansucrase (GS40) was identified within the genome of Leuconostoc mesenteroides YTU 40 that was further cloned, heterologously expressed and biochemically characterised. GS40 was capable of production of a branched dextran with ~ 20% (1→3)-α-D-Glc residues detected by1H and13C NMR analysis. Acceptor reactions of GS40 with maltose and cellobiose were performed and distinct maltose/cellobiose derivative acetylated gluco-oligosaccharides were produced detected by TLC, NMR and LC-MS analysis. The bioactive characteristics of branched dextran and gluco-oligosaccharides were tested by determination of their immune-modulatory roles in terms of triggering IL-12, IL-10, IL-4 and TNF-α cytokine levels. These findings can be important to unveil the role of glucansucrases for the production of gluco-oligosaccharides that can be used as functional ingredients for food and other industries.

    • SDG 3 · Sağlık ve Kaliteli Yaşam
    AtıfScopus3WoS3OpenAlex3
    ScopusWeb of SciencePubMedİncele
  • MakaleAçık Erişim2024Scopus SJRQ1
    Evaluation of lavender essential oils and by-products using microwave hydrodistillation and conventional hydrodistillation

    Kırkıncı, Seran; Gercek, Yusuf Can; Baştürk, Fatma Nur; Yıldırım, Nazlıcan; Gıdık, Betül; Bayram, Nesrin Ecem

    This study investigated the impact of two extraction methods, traditional hydrodistillation (TDH) and microwave-assisted hydrodistillation (MAH), on the essential oil yield and chemical profile of Lavandula angustifolia L., as well as the bioactive potential of the resulting wastewater. Essential oil composition was analyzed via GC–MS, revealing similar qualitative and quantitative profiles for both methods, with α-terpinolene and (–)borneol as major constituents. Wastewater analysis via LC–MS/MS and spectrophotometric assays demonstrated the presence of significant total phenolic content (3.29–1.78 mg GAE/g) and 32 individual phenolics (463.1 µg/kg for TDH; 479.33 µg/kg for MAH). These findings suggest that both essential oil and wastewater obtained by either method possess considerable bioactive potential, with the MAH method potentially offering advantages over TDH for essential oil extraction. Further exploration of wastewater applications in various industrial sectors is warranted.

    • SDG 12 · Sorumlu Üretim ve Tüketim
    AtıfScopus25WoS22OpenAlex22
    ScopusWeb of SciencePubMedİncele