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Article Citation - WoS: 1Citation - Scopus: 1The Effect of Group Behavior on the Pull-Out Capacity of Model Soil Nails in High Plasticity Clay(Springer int Publ Ag, 2024) Akis, Ebru; Bakir, Bahadir Sadik; Yilmaz, Mustafa TolgaSoil nailing technique is widely used in stabilizing roadway and tunnel portal cut excavations. The key parameter in the design of soil nail systems is the pull-out capacity. The pull-out capacity of soil nails can be estimated either from the studies involving similar soil conditions or from the empirical formulas available in the literature. Particularly, it has been documented placing nails closer than a certain minimum distance results in a reduction in the pull-out resistance of a nail placed in sand. However, this requirement has not been discussed for the nail groups located within clay formations. In order to investigate the influence of nail spacing on the pull-out resistance of nails, a series of laboratory pull-out experiments were performed in clay of high plasticity. The results of these experiments showed a remarkable trend. Specifically, there was a significant reduction in the pull-out capacity of a nail when the spacing between nails two times the nail diameter (2 & Oslash;). In contrast, the pull-out capacity of a nail embedded in clay remained unaffected by neighboring nails, provided the spacing was maintained at six times the nail diameter (6 & Oslash;). In addition, during the conducted pull-out tests, it was observed that the failure mode of a single nail and 6 & Oslash; spaced group nails near the surface results as heaving around the single nail. However, in the case of closely positioned (2 & Oslash; spaced) nails, the affected area following nail failure exhibits distinct characteristics, which operate as a group. This leads to the occurrence of failure in the form of heaving around the group of nails.Article Citation - WoS: 2Citation - Scopus: 2Assessment of Tensile Properties of Cast High Mg Containing Al-Mg Aluminum Alloy With Correlation of Computed Tomography Scans and Optical Crack Surface Analysis(Springer int Publ Ag, 2023) Gul, K. Armagan; Dispinar, Derya; Kayali, E. Sabri; Aslan, OzgurIn the casting of aluminum alloys, melt cleanliness has been crucial to achieve desirable final properties. Alloying elements, casting method and degassing procedures have been applied to obtain an internal structure free from defects. Most common defects have been double oxide metal films called bifilms. These defects have been detrimental to mechanical properties. Efforts in industry and academia have focused on removing those defects. Reduced pressure test (RPT) and optical evaluation of cross section of specimens have been the most preferred method of bifilm index evaluation method to assess melt quality. As this method is 2D cross-section analysis, there has not been a direct method to correlate mechanical properties with 3D volume analysis of both RPT and tensile specimens. Computed tomography scanning/imaging has been a promising and emerging method for 3D internal structure evaluation to evaluate internal defects. Subsequent mechanical properties fluctuation in correlation with defect quantity and size may be built in this methodology. In the present study, casting of aluminum alloys with high magnesium content and different alloying elements has been done. Effect of melt quality and defect quantities on internal structures have been investigated via RPT tests and computed tomography scans (CTS). Correlation of CTS and tensile tests has been shown. Tensile test specimen surfaces have been investigated via optical imaging, and bifilm effects have been shown. Alloy quality correlations with tensile tests have been established.Article Citation - Scopus: 1A Critical Review on Multifunctional Building Envelope Materials for Simultaneous Mitigation of Urban Heat and Noise Islands(Springer int Publ Ag, 2025) Sarul, Meltem; Kocyigit, Filiz Bal; Yilmaz, CagriRethinking urban models requires resilient designs providing solutions to environmental problems at the building scale. Urban Heat Islands (UHI) and Urban Noise Islands (UNI) often coexist and significantly affect human health and comfort. This article aims to examine dual-function building envelope materials for reducing urban heat and noise islands using the literature review method. Dual-functional building envelope materials provide versatile benefits such as increasing energy efficiency, mitigating environmental challenges in densely populated areas, and improving individual and social health and comfort, in addition to their thermal and acoustic benefits. The use of these materials in building envelopes supports the climate adaptation of cities and provides resource efficiency.High albedo cool materials used for excessive heat reduction can be in the form of cool roofs or cool walls. High reflective materials, cool colored materials, retro-reflective materials, photoluminescent materials, thermochromic materials and sustainable materials are the most common among the cool material alternatives. The use of natural and local white colored gravel of various sizes on cool roofs is a low-cost and efficient approach to UHI reduction. Cool colored materials reflecting the near-infrared part of the solar spectrum bring a suitable solution for historical buildings where white color application is not appropriate. Highly reflective materials combat heat-related risks by reflecting incoming solar radiation directly back to their source due to their special content. Photoluminescent materials, which are still in the research phase, and thermochromic materials that change color when they reach a predetermined temperature are other solutions used to prevent heat-induced problems. Recycled or paraffin, biowaste oil added Phase Change Materials (PCM) also offer environmentally friendly, sustainable solutions for this case. In terms of UNI mitigating techniques, sound absorbing materials with high sound absorption coefficient and low density are widely preferred for building envelopes. Since high albedo materials generally have low sound absorption capacity, although reduction in heat- and noise-related threats is possible separately with the building envelope materials to be selected, multifunctional surface design diminishing both UHI and UNI effects simultaneously still involves various challenges. However, there are various strategies including applications of green walls and green roofs. Innovative approaches such as the use of PCM in pavements or the conversion of noise into green electricity using resonators or acoustic metamaterials also exist. While such solutions have not yet been widely found in practical applications, they are promising for the resilient smart cities of the future. Further experimental validation is needed to evaluate the long-term performance, cost-effectiveness and climate-specific applicability of multifunctional materials.HighlightsMulti functional building envelope materials that simultaneously address UHI and UNI offer great opportunities to create resilient future designs.Using cool materials in building envelopes mitigate UHI related risks.Using sound-absorbing materials in building envelopes mitigate UNI related risks.Innovative solutions such as phase-changing materials and converting harvested noise into electricity are great future opportunities.Article Citation - WoS: 3Citation - Scopus: 3Development and Validation of a Sensitive Assay for the Quantification of Arachidonoylcyclopropylamide (acpa) in Cell Culture by Lc-ms/Ms(Springer int Publ Ag, 2023) Boyacioglu, Ozge; Recber, Tuba; Kir, Sedef; Korkusuz, Petek; Nemutlu, EmirhanSynthetic and natural cannabinoid derivatives are highly investigated as drug candidates due to their antinociceptive, antiepileptic and anticancer potential. Arachidonoylcyclopropylamide (ACPA) is a synthetic cannabinoid with antiproliferative and apoptotic effects on non-small cell lung cancer and pancreatic and endometrial carcinoma. Thus, ACPA has a great potential for being used as an anticancer drug for epithelial cancers. Therefore, determining the levels of ACPA in biological fluids, cells, tissues and pharmaceutical dosage forms is crucial in monitoring the effects of various pharmacological, physiological and pathological stimuli on biological systems. However, the challenge in the quantification of ACPA is its short half-life and lack of UV signal. Therefore, we developed a liquid chromatography-tandem mass spectrometric (LC-MS/MS) method for sensitive and selective quantification of ACPA in cell culture medium and intracellular matrix. Multiple reaction monitoring in the positive ionization mode was used for detection with 344 -> 203 m/z transitions. The separation of ACPA was performed on C18 column (50 x 3.0 mm, 2.1 mu m) with the mobile phase run in the gradient mode with 0.1% formic acid (FA) in water and 0.1% FA in acetonitrile at a flow rate of 0.3 ml/min. The assay was linear in the concentration range of 1.8-1000 ng/mL (r = 0.999). The validation studies revealed that the method was linear, sensitive, accurate, precise, selective, repeatable, robust and rugged. Finally, the developed method was applied to quantify ACPA in cell culture medium and intracellular matrix.Article Citation - WoS: 5Citation - Scopus: 9The mediating role of FoMO and the moderating role of narcissism in the impact of social exclusion on compulsive buying: a cross-cultural study(Springer int Publ Ag, 2023) Mert, Merve; Tengilimoglu, DilaverBackground There is an interrelationship between the concepts of social exclusion, compulsive buying behavior, fear of missing out (FoMO), and narcissism. Nevertheless, the extent to which these concepts mediate or moderate their relationships with each other has not been efficiently investigated. Objective This research aims to investigate how FoMO mediates and narcissism moderates the correlation between social exclusion and compulsive buying behavior. In addition, the research aims to test a conceptual model and highlight the differences that may occur in the conceptual model proposed in two different countries. Methods This model was analyzed among 1007 university students (Turkey = 506, Denmark = 501). The study used scales to measure social exclusion, compulsive buying behavior, FoMO, and narcissism. The study employed PROCESS Model 4 to analyze direct and indirect (mediation) effects and PROCESS Model 59 to assess conditional (moderation) effects. Furthermore, the Johnson-Neyman technique was utilized to investigate interaction terms. Results The findings indicate that those who face social exclusion tend to participate more in compulsive buying, and this connection is partly explained by FoMO. This suggests that individuals who encounter social exclusion may have an increased likelihood of experiencing FoMO, which may subsequently contribute to compulsive buying behavior. Furthermore, the moderating effect of narcissism differed between the Turkey and Danish samples. Specifically, in the Turkey sample, narcissism only modified the connection between social exclusion and FoMO, while in the Danish sample, it impacted both the connection between social exclusion and FoMO and the connection between FoMO and compulsive buying. Conclusion The obtained results show that the regulating role of narcissism is different in Turkey and Denmark within the conceptual model we studied.Article Simultaneous Removal of Setazol Navy Blue and Cr(vi) by Mixed Microbial Culture Isolated From the Çubuk Stream(Springer int Publ Ag, 2024) Gunduz, A. Irem; Erkoc, Esra; Korkmaz, Filiz; Kilic, Nur KocberberWater samples taken from the & Ccedil;ubuk Stream (Ankara, Turkey) were inoculated into nutrient broth media containing Setazol Navy Blue SBG (SNB), an organic pollutant, and heavy metal Cr(VI), an inorganic pollutant, to obtain a pollutant-resistant mixed microbial culture. Experiments were conducted with this culture to remove SNB and heavy metal. The optimum conditions, where the mixed bacterial culture removed the pollutants most effectively, were determined, showing that the highest capacity for removal took place at pH 8 with removal percentages 96.3% for Cr(VI) and 78.5% for SNB. In media with 50.4 mg/L SNB and 9.7 mg/L Cr(VI), the SNB removal was 87.3%, and the Cr(VI) removal was 96.6% at the end of the 7-day incubation period. The highest removal was observed with a biomass concentration of 8% (v/v) of mixed culture [50 mg/L SNB dye+25 mg/L Cr(VI)]. The removal was 100% for both Cr(VI) and the SNB dye. The bacteria with the highest removal were isolated and identified using 16S rDNA gene sequence analysis as Microbacterium oxydans and Leucobacter aridicollis. The role of various functional groups and the structures of the microorganisms that might be involved in the removal mechanisms were discussed using their FTIR spectra. This report is the first study that investigates a mixed bacterial culture and pure cultures (M. oxydans and L. aridicollis) isolated from that mixed culture, removing both SNB and Cr(VI) simultaneously.
