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Acta Alimentaria
Authors:
M. Reyzov
,
M. Eftimov
,
S. Gancheva
,
M. Todorova
,
M. Zhelyazkova-Savova
,
M. Tzaneva
, and
S. Valcheva-Kuzmanova

Abstract

This study evaluated the effects of Aronia melanocarpa fruit juice (AMFJ) on the liver in a model of high-fat, high-fructose (HFHF) diet-induced metabolic syndrome (MS). Fifty rats were allocated to five groups – Control, MS, MS+AMFJ2.5, MS+AMFJ5, and MS+AMFJ10. The control group was fed a standard diet, while the other groups were provided a HFHF diet. During MS induction, daily oral treatment was performed. Control and MS groups received 10.0 mL kg−1 distilled water, while the other three groups received AMFJ at doses of 2.5, 5.0, and 10.0 mL kg−1, respectively. After 10 weeks, liver samples were collected and inspected histologically as well as immunohistochemically to determine the expression of Bax, Bcl-2, and MAC387. Bax/Bcl-2 ratio was calculated. In MS rats, steatotic, inflammatory and degenerative alterations of the liver were detected, Bax and MAC387 were markedly elevated, while Bcl-2 was non-significantly reduced. The Bax/Bcl-2 ratio significantly increased. The histopathological alterations were prevented by the AMFJ treatment. Compared to MS group, Bax and MAC387 values were significantly lower and Bcl-2 value was higher resulting in significantly lower (P < 0.001) Bax/Bcl-2 ratio in all AMFJ-treated groups. AMFJ, administered during MS induction in rats, prevented the occurrence of inflammatory, steatotic, degenerative, and pro-apoptotic changes in the liver.

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Acta Chromatographica
Authors:
Qing Jia
,
Ziyue Wang
,
Shuqian Wang
,
Shunjun Ma
,
Xueqi Qiao
,
Xueli Huang
,
Xianqin Wang
,
Congcong Wen
, and
Xia-yin Zhu

Abstract

Objective

The levels of fraxetin, fraxin, and dimethylfraxetin in rat plasma to be measured using an ultra-performance liquid chromatography tandem mass-spectrometry (UPLC–MS/MS) technique and applied to their pharmacokinetics and bioavailability.

Methods

The protein precipitation technique was applied to the plasma preparation using acetonitrile and methanol (9:1, v/v). At a flow rate of 0.4 mL min−1, the elution time was 6 min. The mobile phase consisted of acetonitrile-water with 0.1% formic acid, and the chromatographic column was UPLC HSS T3 (50 mm × 2.1 mm, 1.8 μm). Quantitative analysis was conducted using multiple reaction monitoring (MRM) mode and detection was performed using electrospray ionization (ESI) positive ion mode. In each group, six rats were treated with fraxetin, fraxin, and dimethylfraxetin either orally (5 mg kg−1) or intravenously (1 mg kg−1).

Results

The calibration curves showed good linearity in the range of 2–4,000 ng mL−1, where r was greater than 0.99. The bioavailability of dimethylfraxetin, fraxin, and fraxetin was determinated to be 19.7, 1.4, and 6.0%.

Conclusion

The established UPLC-MS/MS method for determining the levels of these three compounds in rat plasma was successfully applied to the pharmacokinetics of dimethylfraxetin, fraxin, and fraxetin, and the bioavailability was calculated.

Open access

Abstract

During the COVID-19 pandemic, the switch to online training exposed the digital divide between higher education institutions, with some significantly superior to others in terms of equipment and experience, as well as among students enrolled in the same institution. The purpose of this study was to investigate online training and educational inequality in TVET (Technical and Vocational Education and Training) delivery in Kenya, during the COVID-19. A total of 16 unstructured discussions were conducted in four TVET institutions in the Western Kenya Region. Each college organized four conversations (two males only and two females only groups). The study took into account various reports and literature to provide the background and analyze the data to respond to the research questions. Additionally, the study collected data through desk reviews, unstructured conversations, reports, emails, WhatsApp messages, and phone calls that aid in situation analysis, utilizing a qualitative research methodology of situational analysis. Lack of experience with online training by trainers and trainees, along with inadequate training assistance, resulted in feelings of anxiety and unease. Trainees were frequently incapable of self-regulation and remained motivated to learn at home and they were unsure about the quality of the materials accessible to them. Recommendations on four major issues are given: providing complete support to trainees, trainers, and other institution personnel; improving remote and online training; ensuring policy certainty, implementation, and monitoring; and discovering and implementing effective interventions and innovations.

Open access

Abstract

International student satisfaction has become a widely studied topic with the emergence of English-language study programs in higher education institutions (HEIs). Numerous studies arose in connection with understanding what factors influence international student satisfaction, determining service elements as crucial indicators of student satisfaction. There is limited research on understanding international student satisfaction in Hungary, explicitly focusing on degree-seeking mobility. Therefore, the current study analyses international students' satisfaction through the example of a Hungarian university to uncover the factors affecting satisfaction and to determine points for improvement of unsatisfied needs. Based on the questionnaire findings, an importance–satisfaction analysis (ISA) was conducted to depict international students' pain points visually. The focus group discussion and the affinity diagrams revealed that international students need more free-time activities and opportunities to connect outside the university. In addition, usability testing highlighted crucial missing information from the university mentor organisation webpage, while the results of the online questionnaire showed that there is an urgent need to develop university services. Besides determining points for improvement, this study provides insights into utilising a comprehensive, novel methodology in researching degree-seeking mobile students in Hungary.

Open access

Abstract

The main concern of this article is to introduce the concept of the authentic gesture as a vital, largely self-determined expression of the child and to make it fruitful for art education. Because of the assumed educational importance of the concept, some hints to other learning areas will also be given. This should be done from a historical and systematic perspective against the background of relevant literature, above all the German-language literature and some other important voices, in which a number of further leading ideas can be found and discussed. Explicated in this way, the concept at issue leads to the question of the unknown per se, to which art education and education in general should open itself. This means that education opens up to something that, in its material and/or social form, evades a final assessment. Something enigmatic thus comes into view, because the unknown, by definition, is beyond exact description and extern evaluation. However, in and for the modern world, it can be paraphrased with a secular approach of transcendence as an inner-psychic space which is withdrawn from instrumental intervention including educational intervention and which must be protected at all costs as a central condition of freedom and human dignity.

Open access

Abstract

The article evaluates how well the goals of the European Green Deal are justified, especially considering the risks to energy and food security arising from the conflict between Russia and Ukraine. We agree with the objectives of the European Green Agreement as a whole, but whether some of the objectives which feature in the EASAC study can be achieved by 2030 is questionable, and the description of the tools necessary to achieve the objectives is incomplete. Among other things, there is hardly any mention of the role played by precision farming with digitalization, which is a revolutionary change from an ecological and economic point of view, in reducing the use of synthetic inputs, in regenerating the original state of the soil, in reducing GHG emissions, thus in increasing biodiversity, and at the same time in intensifying production, and finally in expanding the application of biotechnology. We examine these areas in our analysis. Some of the objectives of the EASAC study to be achieved by 2030 are subject to debate, and the description of the information and communication conditions necessary to achieve the objectives is incomplete. The IoT (Internet of Things) responds to global and local challenges: it integrates the precision technologies, WSNs (Wireless Sensor Networks), artificial intelligence, mobile field (Smart Small Robots) and remote data loggers (UAVs: Unmanned Air Vehicles and satellites), Big Data, and cloud computing. Consequently, decision support is increasingly developing into unmanned decision making. IoT (Internet of Things) is the basis of “Farm to Fork” and “Lab to Field” monitoring approaches.

This article evaluates the implementation of European Green Agreement objectives in light of energy and food security risks arising from the Russia-Ukraine conflict. While overall support for the agreement exists, the feasibility of certain EASAC study objectives by 2030 is called into question due to insufficient tools specifications. Notably absent is the emphasis on precision farming with digitalization, which is a transformative ecological and economic practice. Our analyses look into its function in reducing synthetic inputs, soil regeneration, GHG emission reduction, biodiversity enhancement, production intensification, and biotechnology development. Debates surround EASAC study objectives for 2030, despite limited information and communication restrictions. The Internet of Things (IoT) arises as a solution, combining precision technology, WSNs (wireless sensor networks), AI (artificial intelligence), smart small robots, UAVs (unmanned aerial vehicles), satellites, big data, and cloud computing. As a result, decision support turns toward unmanned decision-making, with IoT laying the groundwork for “Farm to Fork” and “Lab to Field” monitoring systems.

Open access

Abstract

This paper argues that the mitigation of the normative pedagogy in the value heterogenous world has elicited the need to rephrase the teacher's role. While this study cannot reflect on all issues that have recently arisen, some core questions are addressed to examine the teacher-student relationship and highlight a few principles that teachers need to be aware of. This study links to previous works on responsive pedagogy, accepting the ambition to respond to individual needs but also discussing collective terms such as human freedom and cultural differences, which impact children's perspectives.

Accordingly, this paper is an attempt to provide an interdisciplinary framework based on educational philosophy, psychological evidence, and ethnographic studies to discuss the conflict between individual and community interests, basic human needs, individual differences, and ethical issues arising from diverse cultural backgrounds, and some contemporary phenomena that have affected the operations of schools. As a result, following a critical review of the introduced concepts, this paper suggests considering some educational responsibilities that may improve teachers' practice in the 21st century.

Open access

Solidarity – An aim of education?

Reflections on a vital topic of education for sustainable development (ESD) from the perspective of a responsive pedagogy

Hungarian Educational Research Journal
Author:
Alexander Maier

Abstract

The demand for solidarity is made today by different social actors, e.g., from politics, religion or philosophy. Especially in the context of climate change and its social and ecological consequences, the demand for solidarity plays a major role. It is often referred to as the climate justice crisis. Therefore, solidarity can also be understood as a goal of education for sustainable development (ESD). In this context, ESD, which also sees itself as a concept of transformational education, prefers above all elements of a disruptive pedagogy through which students are to be led to new perspectives - for example, to solidarity with the victims of the consequences of climate change. The article takes up this concern of ESD, but would like to look at the educational goal of solidarity from the perspective of a responsive pedagogy. The starting point for this would not be the goals of ESD in the first place, but the needs of children and young people, as Ehrenhard Skiera has highlighted them in the context of his responsive pedagogy. Against this background, the article asks about the possibilities and preconditions for learning processes based on solidarity.

Open access

The use of organic fertilization is declining in Hungary due to the sharp fall of livestock stand since the middle of the 1980s. Most farmers are forced to use solely chemical crop enhancers. A bifactorial small plot experiment was carried out between 10 May 2023 and 19 October 2023 in Keszthely, in order to examine the effects of farmyard manure (M), green manure (GM) and stem residues (SR) on the nutrient uptake and nitrogen utilization efficiencies of maize at equidistantly increasing (0–70–140–210–280 kg N ha–1) nitrogen doses. The relationship between some vegetative traits (dry biomass weight, Leaf Area Index (LAI)) and yield, furthermore leaf relative water content (RWC) was also examined. According to the results, organic fertilizer substitution significantly increased the N content both in whole plant and grain samples of NPK+M and NPK+GM+SR treatments, compared to the chemically fertilized control (NPK). In case of P and K only slight differences were observed. Whole plant K contents of NPK+M were significantly higher than in the other treatments (P = 0.045; P = 0,005), furthermore P contents in grain samples were significantly higher in NPK+M (P = 0.004) and NPK+GM+SR (P = 0.05) than in control. Harvest index (HI [%]) of NPK+M and NPK+GM+SR were 1.06 and 1.05 times higher than in NPK. Depending on the treatment, P0023 maize hybrid absorbed 58.7–74.64% of total N uptake in the grain (HIN%), and the utilization of 1 kg N fertilizer for the extra yield above the yield of the individual control was 0.39–1.38 kg (AREN). Significant positive correlations were observed between dry biomass weight and yield (NPK: r = 0.937, P = 0.019; NPK+M: r = 0.971, P = 0.006; NPK+GM+SR: r = 0.88, P = 0.049), furthermore LAI and yield (NPK: r = 0.9, P = 0.037; NPK+M: r = 0.983, P = 0.003; NPK+GM+SR: r = 0.784, P = 0.117). Highest RWC values – which may be related to better soil aggregate stability – were measured in NPK+GM+SR treatment, therefore there may be a great potential in this treatment among drought conditions. The effect of organic amendments is particularly noticeable with smaller nitrogen doses so they should be used to reduce inorganic fertilizer application and the resulting environmental risks.

Open access

Abstract

Steviol glycosides (SGs) are natural sweeteners derived from stevia leaves, which have various applications in food and beverage products. The extraction efficiency of SGs depends on several factors, such as solvent type, solid to solvent ratio, centrifugal force, and temperature. This study aimed to compare the effects of different solvents (ethanol and water) and leaf moisture (dry and fresh) on the extraction efficiency of major steviol glycosides (SGs) of rebaudioside A (Reb A), stevioside (ST), and rebaudioside C (Reb C) in stevia (var. Levent 93) plant. A Box–Behnken design was used to optimise the extraction parameters for each extraction type. The results showed that ethanol was a more effective solvent than water, however, aqueous extraction was more environmentally friendly and low-cost, and could also yield high concentrations of SGs when fresh leaves were used. The major SGs had similar concentrations in ethanolic extraction, but Reb A was twice as high as ST in aqueous extraction. Reb C was influenced by the solid to solvent ratio in both extraction types, but more so in water extraction. Temperature had a positive effect on ST and Reb C in water extraction of fresh leaves, but not in water extraction of dry leaves or ethanolic extraction. The results of this study contribute to the optimisation of SGs extraction from stevia leaves and provide insights for future research on the effects of different solvents and extraction parameters on the quality and purity of SGs.

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