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Comprehensive flavoromics and lipidomics analyses elucidate the mechanism of star anise in flavor improvement during braised duck leg processing
No full textThis study systematically investigated the mechanism of star anise in modulating the aroma of braised duck leg (BDL) using flavoromics and lipidomics. Six key volatile flavor compounds (D-limonene, linalool, eucalyptol, alpha-terpineol, anethole, and estragole) derived from star anise were found to impart floral, fruity, herbal, and aniselike notes to the BDL. Four potential off-odorants (hexanal, heptanal, 1-octen-3-ol, and 2-pentyl-furan) with rancid, metallic, bloody, and earthy odors in the BDL showed significant positive correlations with oxidation markers, while exhibiting negative correlations with n-9/n-6 unsaturated fatty acids. Non-targeted lipidomics analysis identified polyunsaturated triglycerides (TG), phosphatidylserine (PS), phosphatidylcholine (PC), and cardiolipin (CL) as key differential lipids distinguishing star anise-treated braised duck legs from control samples. Star anise may improve the flavor profile of BDL by inhibiting the thermal oxidation of key lipid precursors, thereby reducing the excessive accumulation of lipid-derived off-odorants.National Key R & D Program of China
2021YFD2100104Fundamental Research Funds for the Central Universities
2662023SPPY00
Floodot-based analysis of floods in turkey and spatial comparison of various data sources
No full textFloods occur when rivers overflow their banks and rapidly spread into surrounding areas, filling nearby depressions and causing both fatalities and economic losses. In this context, the existence of inventories that include various characteristics of floods is of great importance for understanding both the flood generating mechanisms and the consequences they produce. Global inventories have been found insufficient in providing the necessary databases to understand regional and national-scale flood processes in countries like T & uuml;rkiye, while data based solely on newspaper archives or official sources have proven inadequate for explaining such processes. To address this gap, the FlooD Inventory Of T & uuml;rkiye (FlooDOT) was developed. The aim of this study is to introduce the flood inventory created using various data sources for the period between 1928 and 2022 in T & uuml;rkiye, to reveal the temporal and spatial variations of floods based on this inventory, and to compare the spatial differences among the data sources used. In line with this aim, spatial variations of flood inventories obtained from different sources and the hot and cold spots they form were analysed using the Getis-Ord Gi* statistic. According to the results, a total of 3300 fatal floods were identified, and 9181 flood locations were recorded in the inventory based on 6799 flood events. The temporal distribution of floods in Turkey clearly reveals a quarter-century cycle and a bimodal pattern. Furthermore, the years 1972 and 2001 were identified as outlier years in the temporal distribution of floods. While flood events have been observed across the entire country, the Eastern Black Sea region has been identified as a hot spot in terms of both the number of floods and the frequency of fatal floods. Following the Eastern Black Sea basin, the Sakarya and Euphrates-Tigris basins stand out in terms of both fatal floods and total flood occurrences. Moreover, the comparison of spatial differences between the institutional data from the State Hydraulic Works (DS & Idot;) and other sources, based on analyses using the Getis-Ord Gi** statistic, showed that no cold spots were found in Turkey, and that hot spots varied depending on the data source used. This finding indicates that the FlooDOT inventory provides a reliable spatial representation of flood processes in T & uuml;rkiye and helps to fill the data gap created by global inventories. Therefore, utilizing records gathered from all available sources during inventory creation processes offers a significant advantage for flood hazard and vulnerability analyses
Enhanced pid controller tuning for nonlinear continuous stirred-tank heaters using a modified newton-raphson optimizer with random opposition and lévy-flight learning
No full textAccurate temperature regulation in continuous stirred-tank heater (CSTH) systems is vital in chemical and thermal process industries, where deviations can cause energy inefficiencies, product quality degradation, or even safety hazards. However, CSTH systems pose a formidable control challenge due to inherent nonlinearities, parameter uncertainties, and susceptibility to external disturbances. Conventional proportional-integral-derivative (PID) tuning methods often struggle to handle these complexities, resulting in sluggish responses or instability. This study introduces a modified Newton-Raphson-based optimization (mNRBO), for optimal PID tuning tailored to nonlinear CSTH environments. The mNRBO framework integrates two key innovations: random opposition learning, to enhance population diversity and prevent premature convergence, and L & eacute;vy-flight-based guided learning, to improve global exploration and escape local optima. These mechanisms are systematically embedded into the Newton-Raphson-based optimizer (NRBO) to achieve a robust exploration-exploitation balance. A CSTH dynamic model is formulated using mass and energy conservation principles, and a multi-objective cost function evaluates rise time, settling time, overshoot, and steady-state error under realistic process constraints. Simulation studies compare mNRBO with NRBO, hippopotamus optimization, golden eagle optimizer, and slime mould algorithm. Results show that mNRBO achieves the lowest cost function value 53.29, smooth convergence with standard deviation 0.90, and superior closed-loop performance with rise time 62.05 s, settling time 206.88 s, overshoot 1.41%, and steady-state error 0.006%. These findings confirm that mNRBO delivers high-precision, disturbance-resilient control and is a promising solution for industrial thermal processes requiring reliability, efficiency, and precision.European Union under the REFRESH-Research Excellence For Region Sustainability and High-Tech Industries Project via the Operational Programme JustTransition
CZ.10.03.01/00/22_003/0000048National Centre for Energy IIResearch and Innovation Action to Support the Implementation ofthe Climate Neutral and Smart Cities Mission Project
TN02000025ExPEDite through European Unio
Antibiotic resistance in urinary pathogens among kidney transplant recipients: A persistent threat
No full textBackground: Urinary tract infections (UTIs) are the most common infections after kidney transplantation and significantly affect patient outcomes. In these immunosuppressed patients, antibiotic resistance is of particular concern due to recurrent infections and limited treatment options. The aim of this study was to evaluate the distribution of microorganisms isolated from urine cultures of kidney transplant patients and to assess their antimicrobial susceptibility patterns. Methods: This retrospective study included all adult kidney transplant recipients with positive urine cultures during 2023-2024. Microorganisms were identified using matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS), and antimicrobial susceptibility testing was performed with the Phoenix System according to European Committee on Antimicrobial Susceptibility Testing (EUCAST) guidelines. Results: A total of 363 urine samples from 123 patients (85% female) were analyzed. E. coli (49%) and Klebsiella spp. (24%) were the predominant uropathogens. High resistance rates to ciprofloxacin and trimethoprim-sulfamethoxazole (TMP-SMX) were observed in both species, while carbapenem resistance remained low. Elevated resistance to multiple antibiotics was also detected among Pseudomonas aeruginosa and Acinetobacter spp., highlighting the importance of continued microbiological surveillance in this population. Conclusions: Gram-negative bacteria were the predominant pathogens causing UTIs in kidney transplant recipients. The high resistance rates to ciprofloxacin and TMP-SMX emphasize the need for local antimicrobial surveillance and individualized empirical therapy. Systematic and ongoing monitoring of resistance patterns is essential to optimize infection management in this vulnerable patient group
Exploring spatial expectations in a natural playground designed by children for kindergartens
No full textNatural playgrounds in early childhood education support children's development and environmental awareness by offering various experiences. However, in many kindergartens, natural playgrounds are insufficient, and it is emphasized that playgrounds should be improved through participatory design processes carried out with children. The aim of this study is to identify the spatial expectations of five-year-old children regarding natural playgrounds by involving them in a participatory design process at a kindergarten in Bursa, T & uuml;rkiye. A multi-method approach was developed by combining age-appropriate techniques for children within participatory design workshops. Children's explanations of their designs were evaluated through reflexive thematic analysis, resulting in the emergence of eight themes that reflect their spatial expectations for the design of natural playgrounds. The study revealed the play actions children wish to perform, the experiences they desire, and the natural spaces and spatial elements they designed. The findings show that five-year-old children were able to collaboratively design a natural playground through a participatory process. This research highlights the need to increase participatory design practices with children in order to create natural playgrounds that support children's holistic development in kindergartens
Curcumin-loaded akermanite/chitosan/carboxymethylcellulose patches for skin wound healing: Fabrication, characterization, and in vitro cytocompatibility
No full textIn this study, bioactive and biocompatible transdermal patches were fabricated through the lyophilization of a chitosan/carboxymethylcellulose/akermanite composite matrix. The influence of curcumin incorporation at 0.5%, 1%, and 2% on the physicochemical, morphological, and biological properties of the patches was systematically investigated. Scanning electron microscopy revealed an interconnected porous structure with pore sizes ranging from 29 to 57 mu m, facilitating cell infiltration and nutrient transport. Fourier transform infrared spectroscopy and energy-dispersive X-ray spectroscopy confirmed the successful integration of akermanite and curcumin, along with characteristic interactions within the polymeric network. In vitro release studies demonstrated a biphasic profile consisting of an initial burst followed by a sustained release phase, with the CCMAKCur0.5 sample achieving the highest cumulative release (94.28%). Antioxidant performance, evaluated using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) method, ranged from 21.55% (CCM) to 38.96% (CCMAKCur0.5), while higher curcumin concentrations reduced activity due to increased matrix densification. Simulated body fluid immersion confirmed apatite formation, particularly in CCMAKCur0.5 and CCMAKCur2, indicating enhanced bioactivity. Cytocompatibility studies with HUVECs showed no toxic effects, and scratch assays demonstrated that CCMAKCur0.5 most effectively promoted wound closure. Overall, the findings indicate that curcumin- and akermanite-loaded lyophilized patches represent promising candidates for transdermal therapeutic applications
A suggestion for the stages of the portfolio design process
No full textDesigners often create their portfolios as a presentation tool to make their professional competencies visible, to showcase their creative production and to enhance their career prospects. It is thought that graphic designers need a road map that clarifies their goals and enables them to plan the design stages before starting the portfolio creation process. In this study, the document analysis method was used as a data collection tool and a literature review was conducted on the definition and importance of the portfolio, portfolio organization strategies and process and the basic elements that should be considered in portfolio design. This research aims to provide guidance for designers in effectively presenting their work through the portfolio development process. The research offers suggestions for the stages of the portfolio design process. The portfolio design process is examined under seven main headings: self-assessment, determining the purpose and target audience, deciding on the portfolio type, preparing a r & eacute;sum & eacute;, selecting and organizing works, creating the main concept and presenting the portfolio. In this context, it was concluded that the portfolio design process proposed in this study will contribute to the development of goal-oriented and qualified portfolios that systematically and effectively reflect the professional competencies of designers
Reduced-order linearized dynamic model for induction motor-driven centrifugal fan-pump system
No full textThe inherent complexity and nonlinear nature of the dynamic representation of an induction motor-operated centrifugal fan/pump (CFP) system hinders the systematic closed-loop control design for flow rate ([Formula: see text]) and pressure/head ([Formula: see text]) regulation, widely used electrical energy-efficient solution in fluid transport infrastructures and designed intuitively nowadays by practical electrical engineers under the implementation constraints of industrial AC drives. This paper derives the system model allowing direct application of analytical closed-loop control design methodologies, avoiding heuristic solutions and it succeeds in the linearization of an experimentally validated nonlinear six-order dynamic representation of the fan coupled with a scalar-controlled induction machine for an arbitrary operating point. It also reduces the model order via derivations in the stator voltage vector reference frame. The results are verified via simulations and experiments. The analytically derived control-oriented linearized model is of third order and relates small deviations of the stator voltage frequency to the corresponding small deviations of the [Formula: see text] and [Formula: see text], suitable for scalar induction motor regulation applications. The model is presented as block diagrams, in state-space representation and computed as transfer functions. Simulated step responses of the linearized and nonlinear models are close and in good agreement with experimental data. Overall, this paper, for the first time, linearizes and reduces the order of the experimentally validated nonlinear model of the fan-induction motor system accounting for the fan's own dynamics. The obtained model is suitable for analytical closed-loop control design by practical electrical engineers, with following implementation based on industrial AC drives
Estimation of the dominant process parameters on coating thickness in a continuous galvanizing line with computational fluid dynamics and machine learning approaches
No full textIn this study, the dominant process parameters in the air-jet continuous galvanizing line on coating thickness were estimated by computational fluid dynamics and machine learning approaches. First, 128 different cases consisting of different levels of process parameters were created with the Taguchi method. Then, numerical analyses were performed for each case, calculating the maximum pressure gradient and maximum shear stress values on the strip, which were then used in the analytical model developed based on one-dimensional lubrication theory to obtain coating thickness values. Lastly, artificial intelligence techniques based on different machine learning algorithms such as K-Nearest Neighbors, linear regression, random forest and Adaboost, the relative effects of the process parameters influencing the coating thickness were compared through the feature importance values. It was observed that the dominant process parameters differ in low and high jet pressure cases. Accordingly, in the case of low jet pressure, air jet pressure, nozzle slot opening and velocity of the steel strip stand out as the dominant parameters, while in the case of high jet pressure, the most effective parameters influencing the coating thickness are air jet pressure and nozzle slot opening. In addition to this, the effect of the distance between the nozzle and the zinc pot influencing the coating thickness can also be neglected in both low and high pressure cases. Moreover, it was also noticed that the effects of nozzle angle and the distance between the nozzle and the steel strip influencing the coating thickness increase with increasing jet pressure