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The antioxidant effect of melatonin on oxidative stress and vascularization in rat whole embryo culture
No full textHypoxia, during early embryonic development, causes morphological and functional impairments through oxidative stress. Melatonin, a strong antioxidant, may exert potential protective effects in this process. This study investigated the effects of melatonin on yolk sac vascularization and embryonic development in rat embryos exposed to hypoxia. Rat embryos at gestational day 9.5 were cultured for 48 h using a whole embryo culture (WEC) system. Embryos were divided into six groups: Control (C), Hypoxia (H), 10 mu M Melatonin (10 mu M Mel), Hypoxia +10 mu M Melatonin (H + 10 mu M Mel), 50 mu M Melatonin (50 mu M Mel), and Hypoxia +50 mu M Melatonin (H + 50 mu M Mel). At the end of culture, morphological parameters, oxidative stress markers, and the distribution of vWF-positive cells were evaluated. Compared with the control group, the H group exhibited marked developmental delay and vascularization defects (P < 0.05). Melatonin administration significantly reduced these abnormalities, with the 50 mu M melatonin group showing the most prominent improvements in morphological development, oxidative stress parameters, and vascularization (P < 0.05). Melatonin provides protective effects against hypoxia-induced early embryonic developmental impairments and holds therapeutic potential as an agent supporting development during the early intrauterine period. Highlights center dot This study experimentally investigated hypoxia-induced embryonic developmental defects using the Whole Embryo Culture (WEC) model and evaluated the potential effects of melatonin, applied at different doses, on embryo and yolk sac development. center dot The therapeutic potential of melatonin was examined with a multidimensional approach, combining morphological assessment, immunohistochemical analysis (distribution of vWF-positive cells), and biochemical oxidative stress parameters. center dot Findings revealed that embryos exposed to hypoxia showed developmental delay, vascularization defects, and increased oxidative stress; melatonin administration significantly reduced these pathological changes. center dot The main aim was to determine whether melatonin plays a protective role during early embryogenesis through antioxidant, anti-apoptotic, anti-inflammatory, and vasculogenic mechanisms. Results indicated that melatonin may serve as a potential therapeutic agent against hypoxia-induced embryonic damage
Machine Learning-Based Approach for Predicting Hard Landings in Commercial Aircraft
No full textThe landing phase, one of the flight phases, is considered the most critical phase due to its significantly higher accident rate compared to other flight phases. A large portion of accidents occurring during the landing phase consists of hard landings. A hard landing is a landing incident defined as the main landing gear impacting the ground with a greater vertical speed and force than a normal landing. The severity of hard landings can vary from minor passenger discomfort to serious aircraft damage, structural failure, or even loss of life. In this study, the decision-making process regarding go-around maneuvers based on hard landing prediction is addressed using Machine Learning methods, specifically Logistic Regression and Random Forest models. Modeling was conducted using a dataset composed of real-time flight parameters, aiming to prevent hard landing incidents and even landing accidents. The calculation results indicate that the developed models provide accurate predictions for hard landing events
NEW CONCEPTS AND ADVANCED STUDIES IN NATURAL SCIENCE AND MATHEMATICS
No full textIn this study, we investigate the geometric characteristics ofcanal-type surfaces defined in the Euclidean three-dimensional space using theDarboux frame. Surfaces formed by the motion of a sphere along a spine curve,commonly known as canal surfaces, possess rich differential geometric structures. The Darboux frame is afundamental tool in differential geometry used to analyze the local geometry ofcurves lying on the surface. As a surface-adapted version of the Frenet frame,it takes into account the tangent direction of the curve together with thesurface-tangent and surface-normal components. This framework enables adetailed study of geodesic, asymptotic, and curvature lines, offering deeperinsight into the intrinsic geometry of surfaces. First, the fundamentalforms (from the first to the third) of the canal surface expressed in theDarboux frame are obtained, along with the corresponding curvature quantities. And, we focus on Weingartensurfaces, including linear Weingarten canal surfaces, and analyze theircharacteristics in terms of curvature relations. Additionally,we examine developable and minimal canal surfaces, determining the conditionsthat characterize their existence. To validate our theoretical findings, we present a concrete exampleconstructed with specific parametric equations. This example illustrates howthe derived conditions manifest in practice and confirms the applicability ofour approach. The results contribute to the broader study of surface theory andmay be useful in fields such as computer-aided geometric design and theoreticalphysics. Keywords – Euclidean 3-space, Canal surfaces, Darbouxframe, Weingarten surfaces, Linear Weingarten surfaces</div
Determination of Physical Properties of Safflower (Carthamus tinctorius L.) Plant Agricultural Wastes in Different Pellet Diameters
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GREEN ADVERTISEMENTS CONTRIBUTING TO THE DEVELOPMENT OF ENVIRONMENTAL AWARENESS AND EXAMPLE COMMERCIAL FILM ANALYSIS
No full textEnhancing vase life and antioxidant defence in cut stock flowers using nano silver and nano copper vase solution
No full textStock cut flowers have become increasingly popular as cut flowers due to their attractive appearance and pleasant fragrance. The most critical parameters determining quality in cut flowers are vase life and flower quality. In this study, we investigated the effect of adding nano copper, along with sodium hypochlorite and nano silver, to vase solutions, considering their antimicrobial properties and ethylene inhibition potential. Different vase solution treatments, including 20 mg/L nano copper, 20 mg/L nano silver, 3 mg/L sodium hypochlorite, and tap water (control), were applied to cut stock flowers to examine their effects on vase life, relative fresh weight, and daily solution uptake parameters. Based on relative fresh weight and daily solution uptake data, vase solutions containing nanoparticles showed gradual changes without abrupt fluctuations in relative fresh weight and daily solution uptake, indicating an initial increase followed by steady decline over time. Nanoparticle treatments positively affected vase life and flower quality, with nano copper application showing greater efficacy compared to nano silver, resulting in a significant increase in vase life. Additionally, SOD, POX, and CAT antioxidant enzyme activities in nanoparticle-containing vase solutions were identified as antioxidant defence mechanisms that can reduce lipid peroxidation and protect plants against stress. Decreased SOD and POX antioxidant enzyme activities were observed in response to increased proline and CAT levels
