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A multilevel analysis of the effects of daily work stress, daily work to family conflict and emotional stability on daily job engagement
No full text<p>Work-family conflict and work stress among metro drivers, where monotonous and irregular shift conditions are dominant, are one of the important concepts that can have an impact on job engagement. The study aims to analyze the effects of daily work stress, daily work to family conflict and emotional stability on daily job engagement. It adopts a multilevel approach where days are nested in people. Day-level survey data was collected from 40 metro drivers for ten consecutive days in Turkey. Results supported the necessity of using a multilevel approach. According to results, daily work stress and daily work to family conflict negatively and emotional stability positively affect job engagement.</p>
Effect of expanded perlite as an environmentally friendly flame-retardant in semi-rigid polyurethane foam
No full text<p>The objective of the present study is to synthesize semi-rigid polyurethane foam/expanded perlite (SrPUF/EP) composites using different amounts of EP, a natural and environmentally friendly alternative to traditional halogen-containing flame-retardants in a one-step process. This study investigates the mechanical, physical, thermal, and morphological properties, as well as the flame-retardant and smoke release behaviors of composites. The cone calorimetry test results indicated that the amounts of carbon monoxide and carbon dioxide released during combustion process decreased by 43% and 37%, respectively, in the 8% EP-added SrPUF/EP composite (4SrPUF). The amount of char residue formed after complete combustion of 4SrPUF composite was found to be 2.7 times higher than that of pure SrPUF. In the UL-94 test, it was observed that when 4% or more EP was added to SrPUF, the liquid dripping during combustion ceased entirely, and after complete combustion, the main structure remained in the form of char without disintegration. The flexural strength of 1SrPUF, 2SrPUF, and 3SrPUF exhibited increases of 62%, 69%, and 121%, respectively, in comparison to SrPUF (47.15 kPa). The results of this study indicate that EP has the potential to serve as an environmentally friendly and cost-effective flame-retardant, thereby enhancing the fire resistance properties of SrPUF.</p>
<p>Digital images showing the structural changes of pure semi-rigid polyurethane foam (SrPUF) and semi-rigid polyurethane foam/expanded perlite (SrPUF/EP) composites after burning process. image</p>
Production and Characterization of Highly Conductive Aluminum Metal for Electric Motor Applications
No full text<p>The aim of this research is to produce and develop high-conductive and non-magnetic Al-based materials used in industrial rotors to reduce rotor conductor losses and increase motor efficiency. To achieve this, ETIAL 7 Al metal was melted together with AlB2 and AlB12 inoculant materials at individually added proportions (ranging from approximately 0.025-0.300%) using an induction melting furnace. The removal of boron from Al metal was achieved by the interaction of boron with impurity elements at high temperatures and the formation of borides. Low-density metal borides precipitated into slag and high-density metal borides precipitated at the bottom of the molten metal in the induction furnace. As a result, the metal was rendered non-magnetic and its conductivity increased by removing impurity elements in the Al metal. After the casting process, the metal underwent heat treatment to obtain certain textures in the structure, which further enhanced its conductivity at desired directions. The elemental analysis, phase structure, chemical state, microstructural, electrical, and magnetic properties of the produced Al materials were characterized by using OEM, XRD, XPS, SEM-EDS, IA, and VSM. This study has successfully produced extra-high-conductivity and non-magnetic materials with an innovative approach, without changing the system, and in a cost-efficient manner compared to the current situation. These materials can be used to increase the efficiency of electric motors.</p>
Extraction and characterization of microcrystalline cellulose from carrot pomace using green pretreatment technologies
No full text<p>In this study, microcrystalline cellulose (MCC) from carrot pomace, which is a byproduct of the carrot process, was produced. The Response Surface Methodology optimized the effectiveness of autoclaving & ultrasonic pretreatments (AUP) in MCC extraction with a D-optimal design. The yield of AUP was 36.62 % at the optimum point; at the conventional acid hydrolysis method, it was 31.40 %. AUP-derived MCC demonstrated superior rheological properties, including water holding capacity (4.58 g H2O/g MCC) and oil adsorption capacity (2.94 g oil/g MCC), comparable to commercial MCC. Characterization analyses revealed that the AUP-derived MCC had high crystallinity, thermal stability, and a short-fibered morphology, confirmed by FTIR, SEM, TGA, and XRD. Utilizing carrot pomace reduces agricultural waste while providing a valuable dietary fiber source (87.94 % insoluble fiber). This study highlights MCC production from carrot pomace using AUP offers an economically and environmentally viable alternative, with potential applications in food, pharmaceutical, and cosmetic industries.</p>
A new method based on Local Binary Gaussian Pattern for classification of rat estrous cycle stages using smear images
No full text<p>In this study, a unique dataset was created by classifying the images of vaginal smears taken from rats under a microscope for 4 different cycles. Classifying a new case image with the help of this dataset is a computer vision problem. In this study, to improve the weaknesses of the LBP algorithm, a new feature extraction method called Local Binary Gaussian Pattern (LBGP) is developed based on the Gaussian matrix, which helps to remove noise in images. Local Binary Gaussian Pattern proposes a Gaussian-like filter inspired by the Gaussian matrix. After converting the smearing image to the gray histogram, the image features obtained with the help of the Local Binary Pattern (LBP) and our proposed Local Binary Gaussian Pattern (LBGP) feature extractor are combined to obtain features that we call hybrid features. From these features, the ones above a certain threshold value are selected with the help of Neighborhood Component Analysis (NCA), and a Hybrid + Neighborhood Component Analysis (NCA) approach is presented. All hybrid features and hybrid features reduced by Neighborhood Component Analysis were trained with Support Vector Machine (SVM), Decision Trees (DT), Naive Bayes (NB), and k-nearest Neighbors (k-NN) classifiers. According to the classification results, it is seen that the Support Vector Machine (SVM) is effectively classified with the trained classifier. With the Support Vector Machine (SVM) classifier, a success rate of over 90 % (90.25 %) was achieved. Considering the difficulty of classifying smearing images, this result is promising for the future stages of this study.</p>
Investigation of piezoelectric and photoluminescence properties of the multifunctional La<sub>2</sub>Sn<sub>2</sub>O<sub>7</sub> and Ho<sub>2</sub>Sn<sub>2</sub>O<sub>7</sub> pyrochlore smart materials doped with Eu<SUP>3+</SUP>
No full text<p>RE2-xEuxSn2O7 (RE:La3+ and Ho3+, x:0.10) materials were synthesized having both pholuminescence and piezoelectric properties using with solid state reaction method at various reaction temperature and heating duration in open atmosphere. The thermal behaviors, crystal system, surface morphology, EDX analysis, Curie tempereture, photoluminescent properties, dielectric and piezoelectric properties of Eu3+ ions doped La2Sn2O7 and Ho2Sn2O7 were investigated. Both multi-functional smart materials show dielectric, piezoelectric properties and photoluminescence properties which is responsible transitions of doping Eu3+ ions.</p>
Social equality of children in the context of social and political participation with the capability approach☆
No full text<p>This mixed-method study drew on the capability approach and transformative paradigm to investigate the citizenship of children and their social and political participation. This approach was chosen because it focuses on producing policies or projects that can involve different people by considering their capabilities. The study aimed to reveal the importance of children as political subjects in social life. The field research was conducted in I(center dot)zmir Seferihisar Child Municipality ((ISCM)-S-center dot), Turkey. A questionnaire was administered to 116 children, including (ISCM)-S-center dot non/participants. The surveys were conducted under Covid-19 pandemic conditions and public health rules, by making an appointment with each child through the Zoom application and allowing them to see the questions by screen sharing. In addition, in-depth interviews were conducted with 27 adults at the time of conducting the questionnaires. The key results were as follows: children's social and political participation is important; children's political participation is affected by all conditions of the family-school-social environment; the need to participation examples designed as projects need to be transformed into public policies. In addition, considering childhood as preparation for adulthood increases adults' decision-making power over children and impairs their participation. The study provides academic and practical benefits regarding children's political self- being.</p>
Advancements and Applications of 4D Bioprinting in Biomedical Science
No full text<p>The constraints of traditional 3D bioprinting are overcome by 4D bioprinting integrating with adaptable materials over time, resulting in dynamic, compliant, and functional biological structures. This innovative approach to bioprinting holds great promise for tissue engineering, regenerative medicine, and advanced drug delivery systems. 4D bioprinting is a technology that allows for the extension of 3D bioprinting technology by making predesigned structures change after they are fabricated using smart materials that can alter their characteristics via stimulus, leading to transformation in healthcare, which is able to provide precise personalized effective medical treatment without any side effects. This review article concentrates on some recent developments and applications in the field of 4D bioprinting, which can pave the way for groundbreaking advancements in biomedical sciences. 4D printing is a new chapter in bioprinting that introduces dynamism and functional living biological structures. Therefore, smart materials and sophisticated printing techniques can eliminate the challenges associated with printing complex organs and tissues. However, the problems with this process are biocompatibility, immunogenicity, and scalability, which need to be addressed. Moreover, numerous obstacles have been encountered during its widespread adoption in clinical practice. Therefore, 4D bioprinting requires improvements in future material science innovations and further development in printers and manufacturing techniques to unlock its potential for better patient care and outcomes.</p>
Influence of thermoplastic fibre-epoxy adhesion on the interlaminar fracture toughness of interleaved polymer composites
No full text<p>We present an experimental study using surface modification of polyetherimide (PEI) and polyphenylene sulfide (PPS) nonwoven fibrous veils to probe their performance as interleaves to improve the interlaminar fracture toughness (IFT) of carbon fibre-epoxy composites. Veil fibre surfaces were modified with ozone and a posttreatment with ultraviolet (UV) light (ozone + UV). From surface characterisation, mechanical testing of composites and fractography we show that for the PEI veil, these surface modifications resulted in a decreased mode I IFT attributable to decreased fibre-epoxy adhesion and hence, fibre/matrix debonding. In contrast, an increase in sulfinyl functional groups on the surface of PPS fibres after ozonation was observed alongside an increase in PPS veil-epoxy adhesion. The strong bond between fibre-matrix resisted crack propagation across veils, compelling the crack to divert through weaker carbon fibre-epoxy interfaces in adjacent layers. The mode I fracture toughness during crack propagation GIprop decreased, confirming the level of veil-epoxy adhesion to be a significant contributor to the IFT that can be associated with specific functional groups on fibre surfaces.</p>
Early Cretaceous to Eocene magmatic evolution of Livingston Island, South Shetland Archipelago: Geochronological and isotope geochemical constraints from intrusive suites
No full text<p>The magmatic products exposed across Livingston Island comprise a part of the South Shetland magmatic arc built on an active continental margin. The main magmatic phases of Livingston Island include the Early to Late Cretaceous plutonic and volcanic rock associations, the Eocene plutons, and some sporadically distributed intrusions of Paleocene to Eocene dykes. The intrusions were emplaced into the strongly deformed turbiditic sedimentary rocks of the Miers Bluff Formation. 40Ar-39Ar and zircon U-Pb geochronologic data presented here define four distinct episodes of intrusive activity represented by the emplacement of the Hesperides (125 Ma), the Cerro Mirador (104-97 Ma), the Siddons Point (80 Ma) and the Barnard Point suites (42 Ma), in addition to some dyke intrusions with emplacement ages of 105 to 40 Ma. The intrusions are represented by mafic to intermediate compositions characterized by middle potassic, calc-alkaline affinities, with only a few samples from the Eocene activity exhibiting tholeiitic character. Trace element, Sr-Nd-Pb isotope and zircon Hf isotope variations indicate magma generation in a subduction setting with extensive involvement of continental crust-derived melts for the Early to Late Cretaceous activity. The effects of crustal input on melt chemistry appear to have diminished in time, especially from the Paleocene onwards, leading to magma generation with typical oceanic island arc geochemical signatures. This change in melt chemistry is likely partly related to the roll-back induced overriding plate extension which resulted in a time-integrated increase in the rate of melt movement and a decrease in the residence time in crustal levels. Slab steepening caused by the systematic decrease in plate convergence rate led to an enhanced involvement of isotopically depleted mantle component, producing a heterogeneous source with variable subduction signature.</p>