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Multiparitenin serviks dokusu üzerindeki etkilerinin Raman spektroskopisi ile incelenmesi ve bu etkilerin erken doğumla ilişkisinin araştırılması: Sıçan modeli üzerinde çalışma
No full text<p>Amaç: Erken doğumun öngörülmesi anne ve bebek sağlığı açısından yaşamsal öneme sahiptir. Ancak günümüzde kullanılan yöntemler, erken doğumun saptanmasına ve etkili şekilde tedavi edilmesine yeterince imkân vermemektedir. Dokuların tahribatsız, ön hazırlıksız olarak incelendiği bir yöntem olan Raman spektroskopisi ile serviks dokusunun nullipar ve multipar ratlarda incelenmesi, bu sayede erken doğum öngörüsünün daha hassasiyetle belirlenmesini sağlayacak bulguların araştırılması amaçlanmıştır.</p>
<p>Gereç ve Yöntemler: Gebeliğin 15., 17., 18., 19. ve 20. günündeki, onar adet nullipar ve multipar Wistar-Albino ratın serviks uterileri çıkarılıp, Raman spektroskopisi ile incelendi. İnceleme sırasında serviksin vajinaya bakan yüzünden üç, uterus tarafından üç, serviks kanalı tarafından da altı nokta üzerinden 785 nm lazer dalga boyunda ölçümler alındı.</p>
<p>Bulgular: Gebeliğin farklı günlerinden itibaren endoserviks tarafında daha belirgin ve önce ortaya çıkan birçok belirteç saptanmıştır. Bu belirteçlerin kolajenin stabilitesini ve sarmal yapısını, proteoglikan miktarını, hidrasyonu, prostaglandin öncüsü olan lipidlerle ilgiliydi. Ayrıca doğumdan hemen önce servikste kolajen yıkımına neden olan birçok yolağı başlatan makrofajlara ait belirteçlerde de endoserviks tarafında daha erken değişiklikler görülmüştür.</p>
<p>Sonuç: Sonuçlar doğum öncesi serviksin hazırlanmasına ait hücre içi sinyal mekanizmalarına ait değişikliklerin endoserviks tarafında daha erkenden meydana geldiğini ve Raman spektroskopisinin bunları saptayabildiğine dair öncü bulgulara işaret etmektedir. Bu bulguların eş zamanlı olarak hücre içi gen ekspresyon analizi, enzim sentezinin indükleyicileri ve inhibitörlerinin kullanılması ile Raman spektroskopisi ölçümlerinde değişikliklerin saptanması çalışmaları ile doğrulanması gerekmektedir.</p>
Movements and habitat use of native and invasive piscivorous fishes in a temperate and channelized lowland river
No full text<p>Lowland temperate rivers provide important habitats for piscivorous fishes, but with their year-round spatial and temporal habitat use is often poorly understood, including their use of off-channel habitats. Here, the movements and habitat use of the piscivorous native Northern pike Esox lucius and invasive pikeperch Sander lucioperca were investigated using acoustic telemetry in the highly regulated (through impoundment) lower River Severn, Western England over a 12-month period, where off-channel habitat availability was limited to a single boat marina. The movements of both species varied with season and temperature, with both species moving greater distances in spring. Increasing water temperatures up to 15 degrees C resulted in a higher frequency of movements of both species, but movements then decreased at temperatures higher than this. Northern pike detections in the river increased in periods of lower river discharge and warmer temperatures, with the off-channel refuge providing an important habitat all year round (78% of detections occurred there). While 63% of pikeperch detections also occurred in the marina, 89% of these detections occurred between December and April. These results thus emphasise the importance of this limited off-channel habitat as potential spawning locations for invasive pikeperch and foraging areas for native Northern pike.</p>
NbMoVTa refractory high-entropy alloy incorporated WNi matrix composite as a future plasma-facing material: Evaluation of mechanical properties and helium ion irradiation behavior
No full text<p>Refractory high-entropy alloys (RHEAs) have gained attention in the last decades with their high mechanical strength, self-healing mechanism, and high irradiation resistance. These materials are evaluated to have a high potential as plasma-facing materials for fusion reactors. In this study, helium ion irradiation and mechanical behaviors of the RHEA-reinforced WNi matrix composites were investigated based on this perspective. Equimolar molybdenum, niobium, tantalum and vanadium powders were mechanically alloyed for 6 h to produce NbMoVTa RHEA with a single BCC phase. Then, different amounts (10, 20, 30, and 40 wt%) of RHEA were added into the W1Ni (containing 99 wt% W and 1 wt% Ni) matrix by planetary ball milling for 72 h. Consolidation was conducted by spark plasma sintering technique (1410 degrees C, 1 min). X-ray diffraction, scanning electron microscopy coupled with energy dispersion spectroscopy, and Archimedes' density analyses were performed on the composites. Moreover, wear and hardness properties of the composites were examined, and the lowest specific wear rate (0.59 mm3/N.m x 10- 5) and the highest hardness value (10.10 GPa) were found for the W1Ni-40RHEA composite. Helium irradiation was exposed to the composites to observe their irradiation resistance. It was observed that the lowest increment and the least deformation were obtained with the SPS'ed W1Ni-40RHEA composite. With the analysis of He+ irradiation, it was determined that the effect of radiation on mechanical properties is irrelevant. Also, it was observed that the addition of RHEA into the W matrix can create a high potential for using plasma-facing material. Moreover, it decreased the problems of tungsten against He+ irradiation.</p>
System Architecture and Location Accuracy in Developing an Augmented Reality Application for Mnemotechnics: The Case of İzmir Kültürpark
No full text<p>Bu çalışma, hafıza sanatı (mnemonik teknikler) kurallarını temel alan bir Artırılmış Gerçeklik (AR) uygulamasının geliştirilmesini konu almaktadır. AR uygulamaları, tümüyle ya da kısmen yıkılmış mimari miras alanlarının tarihî verilerle birlikte Bilgisayar Destekli Tasarım (CAD) programları aracılığıyla yapılandırılmış hallerinin gerçek dünyaya entegre edilmesine olanak tanır. Oluşturulan yapıların yalnızca tasarımı değil, uygun noktalara yerleştirilmesi de AR deneyimini daha gerçekçi ve akılda kalıcı hâle getirmektedir. Bu doğrultuda, projede kullanılmak üzere İzmir Kültürpark’ta 1938’de inşa edilen üç pavyon binası (İzmir Vilayet, İnhisarlar, İş Bankası) için birden fazla konum doğrulama yöntemi önerilmiştir. Bu yöntemler arasından GPS ve QR kod tabanlı hibrit konumlama kullanılarak yüksek doğruluk hedeflenmiştir. Ayrıca, pavyonlar için mekânsal yeniden yapılandırma, vurgulanmış anlatı ve bindirilmiş görüntüler gibi farklı temsil biçimleri sunulmuştur.</p>
Impact of geohazards on cadastral data: an assessment after the 6 February 2023 Kahramanmaras earthquakes (Türkiye)
No full text<p>Humans set boundaries on land for thousands of years. Cadastre emerged as a system for registering them, whether they are marked on the ground (visible) or unmarked (invisible). Parcel boundary data stored in geospatial databases and supported with registration documents are legally binding in many countries. They are however subject to change physically due to anthropogenic activities and natural processes. Seismic activities inducing surface rupture, lateral spread, landslide, liquefaction, and rockfall are among the main natural causes yielding physical boundary alterations. Spatial pattern and magnitude of alterations depend on the geohazard type and geological characteristics of the area. If a cadastral database is not updated, the physical and registered boundary begins to diverge, leading to uncertainty that needs to be understood by both people and authorities. As a prominent example, the 6 February 2023 Kahramanmaras (Turkiye) earthquakes (Mw7.7 and Mw7.6), which affected a very large region covering approximately 100,000 km2, caused enormous alterations on the physical boundaries of approximately 5 million land parcels. In this study, we analyzed different boundary changes caused by this major event and proposed a conceptual framework based on physical, documentary, and spatial boundary definitions of cadastral parcels with examples from the Kahramanmaras earthquakes. Considering the size of the area and the immense cost of cadastral renovation projects, we analyzed the deformation patterns and possible magnitudes from an interdisciplinary perspective and presented an overview. The study findings provide insights for addressing boundary discrepancies, although additional research is required for comprehensive quantitative assessments across the entire area.</p>
Experimental performance investigation of high reflective and diffuse reflective concentrating photovoltaic/ thermal (CPVT) systems using non-imaging concentrators from energy, exergy, and economic viewpoint
No full text<p>A diffuse reflective (DR) surface in a concentrating photovoltaic thermal system (CPVT) system can provide uniform solar energy dispersion, minimizing hot spots, uneven lighting, and efficiency loss compared to costlier, highly reflective (HR) surfaces. This study uniquely compares the performance of HR-CPVT and DR-CPVT systems, highlighting the significant thermal and electrical efficiency of HR-CPVT while demonstrating the cost-effectiveness of DR-CPVT. The direct comparison of these systems under varying conditions provides novel insights into the trade-offs between high performance and economic feasibility. The performances of CPVTs were examined under various seasonal and weather conditions. The advantage of HR-CPVT was less pronounced in autumn due to seasonal effects. In the summer season, the cooling effect of water becomes more prominent, and the HR-CPVT outperformed the DR-CPVT by 6.1 to 8.5 %, depending on the mass flow rate in terms of overall efficiency. This advancement majorly arises from thermal efficiency. HR-CPVT achieved about a 5.6-7.9 % larger thermal efficiency. However, the electrical efficiency difference was minimal (similar to 0.5 %) and diminished to 0.1 % in the afternoon due to practical PV power generation limits. Despite its high reflectivity, HR-CPVT showed only marginal exergetic benefits over DR-CPVT. The simple payback period was calculated to be 3.65 years for HRCPVT, while it was only 3.19 years for DR-CPVT due to its lower installment cost. RSM analysis accurately predicts the experimental results.</p>
Development an effective adsorptive treatment strategy for the removal of cadmium from textile wastewater by CuBi<sub>2</sub>O<sub>4</sub>@Fe<sub>3</sub>O<sub>4</sub> nanocomposites
No full text<p>In this study, copper-bismuth oxide/iron oxide (CuBi2O4@Fe3O4) nanocomposites were prepared by microwave-assisted synthesis and used as adsorbents for the adsorptive removal of cadmium from textile wastewater. The pH/volume of buffer solution, mixing type/period and adsorbent dosage were optimized univariately to enhance the removal efficiency of the adsorbent and determined as 1.5 mL of pH 8.0 buffer solution, vortexing for 60s, and 30 mg of CuBi2O4@Fe3O4 nanocomposite material. Following the determination of the optimum parameters, equilibrium adsorption studies were performed at five different initial concentrations of cadmium within the range of 0.50 - 10 mg L-1 in textile wastewater. A matrix-matching calibration strategy was utilized for the accurate and precise quantification of cadmium in the wastewater matrix with a R-2 value of 0.9961. The percent removal efficiencies were calculated within the range of 77.2 - 81.5% for the adsorptive removal of cadmium ions from textile wastewater in the equilibrium adsorption experiments. Furthermore, the Langmuir, Freundlich, and Sips adsorption isotherm models were employed for modeling the equilibrium data, and the results showed that all the models fitted well with the experimental data with R-2 values higher than 0.99. The simple and efficient batch adsorption process developed was successfully utilized to remove cadmium ions from textile wastewater.</p>
Entrepreneurial back-to-landers: Neo-farmers in Turkey
No full text<p>Urban-to-rural migration, particularly back-to-land migration, has become prominent in Turkey. This paper focuses on entrepreneurial back-to-landers or neo-farmers, who have migrated to rural areas specifically to get into commercial agriculture and farming. Through an analysis of semi-structured interviews with 72 neofarmers, the paper identifies six critical attributes that aid them during entry into farming and later on, when they are running successful farm businesses: possession of financial wealth; ownership of agricultural land; familiarity with agro-food sectors; education (in agricultural and/or food sciences); experience with corporate conduct; and active connections to the local and/or national organizations associated with the food movement. The paper argues that these attributes feature entrepreneurial skills, experience and connections, which in turn provide neo-farmers with economic, social, and cultural capital and comparative advantages to run their farm businesses. Through the case, the paper shows that one, the direction of capital flows, which historically has been rural-to-urban, may change to urban-to-rural (and from non-agricultural sectors to agriculture) through entrepreneurial back-to-land migration; and two, entrepreneurial skills have become vital for smallholders - newcomer or continuer - if agriculture is going to be their primary income generating activity.</p>
Structural design and mechanical analysis of small-caliber bilayer vascular prostheses
No full text<p>This research comprehensively addresses the influence of structural properties and polymer type on the mechanical performance of bilayer vascular grafts. The grafts consist of inner layers with randomly distributed polycaprolactone(PCL)/polylactic acid(PLA) or poly(l-lactide-co-caprolactone)(PLCL) fibers and an outer layer with radially oriented PLCL fibers, manufactured through a sequential electrospinning process. Highlighted results indicate that tubular scaffolds possess an inner layer ranging in thickness from 62 to 94 mu m, while their outer layers vary in thickness from 180 to 296 mu m. In addition, radially oriented fibers enhance tensile strength in radial direction (9-11 MPa), while depending on polymer composition and wall thickness proportions of individual layers, tensile strength values change between 2.7 and 7.7 MPa in longitudinal direction. Scaffolds with elastic PCL or PLCL inner layers display higher compliance values (above 1%/mmHg x 10(-2)). [Graphical Abstract]</p>
Recent developments in electrochemical sensors and biosensors for food additives determination: Principle and application
No full text<p>Food additives (FAs) are natural or synthetic compounds added to food products to preserve flavor or improve taste. FAs can be classified into many groups, including sweeteners, preservatives, antioxidants, stabilizers and thickeners, emulsifiers and emulsifying salts, and color and color retention agents. To ensure the safety and quality of food products, it is essential to develop accurate and reliable methods for detecting and quantifying FAs. Electrochemical sensors have emerged as promising tools, as they can be designed to detect various FAs. Various materials are employed to modify the sensitivity and selectivity of electrochemical sensors for FAs. This review provides a comprehensive overview of the classification of FAs and recently developed electrochemical sensors/biosensors for their detection, highlighting their advantages, limitations, and food safety applications. Finally, future aspects are discussed by referencing recent critical studies, aiming to advance research in developing novel functional electrochemical (bio)sensors for food safety and contamination detection.</p>