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Investigation of fresh and hardened properties of 3D printable concrete containing ozone-modified carbon fiber
No full text<p>In this study, the effect of using carbon fiber surface modified with ozone on the fresh-hardened state properties, high temperature resistance and rheological properties of 3D printable concrete (3DPC) was investigated. A total of 7 different 3DPC were prepared by adding modified and unmodified carbon fibers to the mixture at different ratios. Fiber surface modification was characterized by XPS analysis. The modification process improves the fiber/matrix adherence of 3DPC mixtures, resulting in an increase in compressive strength. The flexural strength of the mixtures increases with fiber modification, regardless of the fiber utilization ratio. Dynamic yield stress and apparent viscosity values of the mixtures decreased with the increase in fiber utilization ratio. tau 3.p/tau 2.p and Athix methods are more suitable for comparing the thixotropic properties of 3DPC mixtures with modified fibers suitable for comparing the thixotropic properties of 3DPC mixtures with modified fibers.</p>
Increased spread risk of citrus long-horned beetle [<i>Anoplophora chinensis</i> (Coleoptera: Cerambycidae)] under climate change in Türkiye: Implications for management
No full text<p>Climate change and increasing global trade are facilitating species' introduction and establishment outside their native ranges. Predicting likely introductions and spread areas could help to lower the introduction and spread risk of new species through biosecurity measures. The citrus long-horned beetle (Anoplophora chinensis) is a polyphagous species native to Asia and causes significant damage to several tree species. Anoplophora chinensis (ANOLCN hereafter) has been introduced and spread to various geographical regions, including T & uuml;rkiye. It is regulated as a quarantine pest in T & uuml;rkiye; however, continuous range expansion is being observed in the country. This study predicted habitat suitability of ANOLCN in T & uuml;rkiye under SSP1-2.6 and SSP5-8.5 climate change scenarios by using optimized MaxEnt model. The MaxEnt model was trained and tested with 606 global occurrence records and 13 bioclimatic variables (bio1, bio2, bio3, bio4, bio5, bio6, bio8, bio9, bio12, bio13, bio14, bio15, and bio17). Habitat suitability was predicted for current (1979-2000), and future (2021-2040, 2041-2060, 2061-2080 and 2081-2100) periods. The model predicted habitat suitability with high accuracy (AUC >0.97). Annual mean temperature (bio1), mean diurnal range (bio2), temperature seasonality (bio4), and precipitation of wettest month (bio13) were predicted as the most important variables affecting habitat suitability of ANOLCN. Results indicated that western and eastern coastal areas of Black Sea region, and some coastal areas in the Aegean and Mediterranean Seas have highly suitable habitats for ANOLCN. Highly suitable habitat will expand by 5.99-69.33% under SSP1-2.6 and 13.31-45.78% under SSP5-8.5 climate change scenarios compared to current climate. The areas with highly suitable habitat have intensive citrus, hazelnut and olive cultivations, indicating higher and stronger ANOLCN infestation in the future. Therefore, timely and effective management strategies, including strict quarantine regulations are needed to combat the ecological and economic threats posed by ANOLCN in the future.</p>
"An Experimental Study; Botox and Nicotine: How Effective Can It Be in Flap Surgery?"
No full text<p>In this study, the effects of nicotine and botulinum toxin (BTx) on perforator flap microcirculation were compared with the control group. We took 40 rats and cut a 6 cm x 6 cm perforator skin flap from the right superior deep epigastric artery. We then divided the rats into four groups: control, nicotine, BTx type A, and nicotine + BTx type A. We measured and statistically compared the necrosis rates of the flaps in the photos taken on the 7th day after surgery. We also evaluated tissue samples for gene expression, histopathology, and immunohistochemistry. In the BTx group (p = 0.01) and the nicotine + BTx group (p = 0.041), the necrotic area decreased significantly. There was a lot less CD34 and HIF-1alpha gene expression in the BTx (p = 0.009, p = 0.047) and nicotine + BTx (p = 0.001, p = 0.027) groups than in the control group. In the histopathological evaluation, we observed a significant increase in the number of newly formed vessels in the BTx group (p = 0.03) and nicotine + BTx group (p = 0.003). There was a significant increase in CD34 expression in the BTx group (p = 0.001) and the nicotine + BTx group (p = 0.02), as well as a significant increase in HIF-1 alpha expression in both the BTx group (p = 0.003) and the BTx + nicotine group (p = 0.05). In this experimental study, we believe that applying BTx alone or in combination with nicotine to rats with perforator flaps may be beneficial in terms of flap viability and microcirculation. Level V (Animal/Experimental Study).</p>
Kişisel Verilerin Bilimsel Araştırmalarda Serbest Kullanımı ve Sınırları
No full text<p>Bu çalışmada, kişisel verilerin bilimsel araştırmalarda kullanımında karşılaşılan; aydınlatma, açık rıza ve etik kurul sorunlarının, kişisel verilerin bilimsel araştırmalarda serbest kullanımı istisnası ve sınırları dikkate alınarak çözüme kavuşturulması amaçlanmaktadır.</p>
<p>Çalışma, normatif bir araştırma olup aynı zamanda karşılaştırmalı hukuk araştırması da yapılmıştır. Bu kapsamda; iç hukuk, düzenleyici ve denetleyici kurum kararı ve karşılaştırmalı olarak da yabancı hukuk ele alınmıştır.</p>
Investigation of the effect of weave and elastane yarn use on auxetic woven fabric formation and various physical performance parameters
No full text<p>Purpose - Materials with negative Poisson's ratio are known show improved performance properties. By designing woven fabric structures with auxetic properties, it would be possible to add many functional features to the structure in a single step compared to conventional fabric structures. This study investigated the weave designs for forming auxetic woven fabric structures and also the effects of using elastane yarns on Poisson's ratio and possible auxetic performances. Design/methodology/approach - Weave pattern designs consisting of re-entrant honeycomb and re-entrant zigzag forms, created by long floats and one-to-one intersections of yarns, were included in fabric structure. In addition, fabrics were woven by inserting weft yarns with and without elastane component to evaluate the effect of using elastane component on the auxetic performance. For this purpose, fabrics were woven with 100% polyester warp and weft yarns. Measurement of air permeability and % wetting area of fabrics under different elongations were carried out. Findings - Results showed that NPR could be obtained from the designed patterns creating re-entrant honeycomb and re-entrant zigzag geometrical forms on the fabric surface. Also, it was found that the use of elastane yarn had an improving effect on auxetic performance of the woven fabrics. Originality/value - By designing auxetic structured woven fabrics could be preferred in areas of use where clothing comfort was desired, due to the transverse expansion behavior as a result of the auxetic effect due to tension and the resulting pore opening effect.</p>
Core-shell aerogel design for enhanced oral insulin delivery
No full text<p>Current protein-based therapies often rely on intravenous and subcutaneous injections leading to patient discomfort due to the need for frequent administration. Oral administration route presents a more patientfriendly alternative, but overcoming the challenge of low drug bioavailability remains paramount. This limitation is primarily attributed to protein degradation in the harsh gastric environment, enzymatic breakdown, and poor intestinal permeability. With their unique properties, such as high porosity and surface area, and easy scalability, aerogels offer a promising platform for oral delivery of therapeutic proteins. This study focused on the development and characterization of both conventional and core-shell aerogels derived from natural polysaccharides for the oral delivery of insulin, utilizing Humulin R (R) U-100 as the insulin source for the first time. Aerogels were produced via supercritical carbon dioxide (sc-CO2) drying of alginate gel beads. Scanning Electron Microscopy (SEM) images confirmed that the core-shell aerogels had higher uniformity in size and a more welldefined porous structure in comparison to conventional aerogels. Structural differences of two alginate sources were evaluated by Fourier Transform Infrared (FTIR) spectroscopy. A notable difference in encapsulation efficiencies was observed between conventional (12 %) and core-shell (53 %) aerogels, highlighting the superior carrier characteristics of the latter ones. In vitro insulin release profiles from the core-shell aerogels demonstrated their potential suitability for delivering regular/short-acting insulin therapeutics since only 30 % of insulin was released in Simulated Gastric Fluid (SGF) after 120 min, whereas 60 % of insulin was released in Simulated Intestinal Fluid (SIF) within the first hour followed by a sustained release stage.</p>
A comprehensive study on the effects of printing parameters on the mechanical properties of PLA
No full text<p>PurposeThis study aims to investigate the effects of five different printing parameters, namely, printing speed (PS), printing temperature/nozzle temperature/extrusion temperature, heated-bed temperature, raster angle (RA) and layer height (LT), on mechanical properties.Design/methodology/approachAmerican Society for Testing and Materials (ASTM) standards were used for the specimen design. Then, the Taguchi method was used for the design of the experiment and an L16 orthogonal array was preferred. Tensile, Shore D and surface roughness tests were conducted on polylactic acid test specimens. The test results were analyzed using the signal-to-noise ratio and analysis of variance (ANOVA).FindingsAs a result of the study, it was seen that RA is the most important parameter for the tensile strength, PS is for the hardness and LT is for the surface roughness. According to the ANOVA results, the effects of the RA, PS and LT on the maximum tensile strength, hardness and surface roughness were 41.59%, 69.51% and 44.6%, respectively.Originality/valueTo the best of the authors' knowledge, this study is one of the most comprehensive parameter optimization studies for additive manufacturing in the literature because it includes five different printing parameters and three mechanical test procedures.</p>
Transcription factors, nucleotide excision repair, and cancer: A review of molecular interplay
No full text<p>Bulky DNA adducts are mostly formed by external factors such as UV irradiation, smoking or treatment with DNA crosslinking agents. If such DNA adducts are not removed by nucleotide excision repair, they can lead to formation of driver mutations that contribute to cancer formation. Transcription factors (TFs) may critically affect both DNA adduct formation and repair efficiency at the binding site to DNA. For example, "hotspot" mutations in melanoma coincide with UV-induced accumulated cyclobutane pyrimidine dimer (CPD) adducts and/or inhibited repair at the binding sites of some TFs. Similarly, anticancer treatment with DNA cross-linkers may additionally generate DNA adducts leading to secondary mutations and the formation of malignant subclones. In addition, some TFs are overexpressed in response to UV irradiation or chemotherapeutic treatment, activating oncogenic and anti-oncogenic pathways independently of nucleotide excision repair itself. This review focuses on the interplay between TFs and nucleotide excision repair during cancer development and progression.</p>
Cationic dye biosorption from aqueous solution using sunflower tray and process optimization
No full text<p>In recent years, the level of water resources around the world has been decreasing due to global warming, climate change and increasing consumption. In addition, the developing industry pollutes existing water resources. This situation negatively affects all living things on earth. In this study, the biosorption process of cationic dye methylene blue (MB), which was selected as a model dye compound from residual water, and sunflower tray biosorbent was discussed. It was seen that the amorphous structure of the sunflower tray was similar to the hexagonal structure. The process parameters were investigated to reach the highest biosorption efficiency. The highest efficiency (99%) was achieved at pH 6, biosorbent dose 10 g/L, dye concentration 10 mg/L and temperature 20 degrees C. It was determined that the biosorption process with an exothermic reaction was compatible with the Langmuir isotherm (R2 = 0.96) and the pseudo-second-order (PSO) kinetic model (R2 = 0.99). qmax was calculated as 117.6 mg/g. Delta G values suggested that the interaction between the sunflower tray and MB molecules was not spontaneous.</p>
A newly discovered <i>Hystrix primigenia</i> specimen from the Kemiklitepe collection at Ege University Natural History Museum: insights into paleobiogeography in Eurasia
No full text<p>Porcupines, members of the Hystricidae family, represent a unique group of herbivorous mammals. This study details the identification of a newly discovered mandible fragment of Hystrix primigenia, along with a right cheek tooth series from the middle Turolian Kemiklitepe-A fossil locality. While Hystrix fossils are found in numerous localities, the materials are often limited to a few dental fragments or isolated teeth, posing challenges to systematic investigations. The examination of this lower tooth series prompted a comprehensive review of all H. primigenia findings across Eurasia, shedding light on its adaptive characteristics over time and space. Our paleobiogeographical analysis indicates the absence of H. depereti in Late Miocene Turkiye, while the dispersal range of H. primigenia is broader than that of H. depereti in Eurasia. Additionally, the study delves into the discussion of H. primigenia and H. depereti findings in Eurasia, ultimately refining the categorization of Late Miocene Hystrix discoveries in Turkiye to two species: H. primigenia and H. kayae. Our review suggests the possibility of an additional H. kayae finding from Samos, Greece.</p>