Search

This research aims to explore the acceptance of unconventional food products that convey creative solutions for sustainable food production and consumption. This paper presents the first stage results of an extensive Baltic Sea region’s population survey organized to understand how innovative food products’ creators could better enhance the link between sustainable products and different segments’ customer acceptance. In scope of this study, the authors focused on youth market segments, who are known for their adventurous and experimental eating habits. The authors hypothesized that products that have been created to comply with socially responsible and sustainable food products’ requirements face resistance from the youth who do not view them as superior to conventional ones. The cross-sectional study utilized mixed-method methodology, combining qualitative and quantitative approaches, including a literature review, in-depth focus group interviews, and comparative analysis using normal distribution assessment and sentiment classification. The research findings indicate that while the youth acknowledge the social and environmental benefits of innovative food products, they remain hesitant to adopt them personally. Therefore, it is vital for innovative food creators to understand the biases and behaviors of young consumers, ensuring transparency about product contents, motivating them to embrace new consumption models, try unconventional foods, and highlight the personal and societal advantages of purchasing these items.

The current investigation presents porous ceramic materials prepared with cenospheres (CS) by using spark plasma sintering. The impact of sintering temperature, mould diameter (20, 30 and 50 mm) and cenosphere size on the properties of the sintered material was investigated. Shrinkage of the samples during sintering started at 900 °C. Total sample shrinkage during sintering increases with increasing temperature and decreases with increasing mould size; increasing sample sintering temperature increases the apparent density of all sample series CS 63–150 µm in a 20 mm mould from 0.97 to 2.3 g·cm−3 at 1050–1300 °C; in a 30 mm mould, 0.81–1.87 g·cm−3 at 1050–1200 °C; in 50 mm mould, 0.54–0.75 g·cm−3 at 1050–1150 °C; while CS 150–250 µm in a 20 mm mould is 0.93–1.96 g·cm−3 at 1050–1200 °C. Total porosity decreases from 61.5% to 3.9% by increasing sintering temperature from 1050 to 1250 °C, while open porosity reduces at lower temperatures, with closed porosity being highest in samples sintered at 1150 °C. When the sintering temperature increases from 1050 to 1300 °C, the compressive strength of the CS 63–150 samples produced in a 20 mm mould increases from 11 MPa to 312 MPa. These results correlate with the Rice model, which describes an exponential dependence of compressive strength on material porosity and fully dense material compressive strength.

The present study focuses on the synthesis and characterisation of a lightweight ceramic material with electromagnetic interference (EMI) shielding properties, achieved using mullite containing micrometre-sized hollow spheres (cenospheres) and CoFe2O4 nanoparticles. This research explores compositions with varying CoFe2O4 contents ranging from 0 up to 20 wt.%. Conventional sintering in an air atmosphere is carried out at a temperature between 1100 and 1300 °C. The addition of ferrite nanoparticles was found to enhance the process of sintering cenospheres, resulting in improved material density and mechanical properties. Furthermore, this study reveals a direct correlation between the concentration of ferrite nanoparticles and the electromagnetic properties of the material. By increasing the concentration of ferrite nanoparticles, the electromagnetic shielding effect of the material (saturation magnetisation (Ms) and remanent magnetisation (Mr)) was observed to strengthen. These findings provide valuable insights into designing and developing lightweight ceramic materials with enhanced electromagnetic shielding capabilities. The synthesized ceramic material holds promise for various applications that require effective electromagnetic shielding, such as in the electronics, telecommunications, and aerospace industries.

Economic growth increases the pressure on environmental issues, thus highlighting the importance of waste minimization processes. The waste management approaches in most European countries have so far been relatively little studied and compared at the micro level. The main objective of the current research is to analyze the challenges of waste minimization in European food industry enterprises and identify good practices in the selected countries. The research used a mixed-method methodology, combining both qualitative and quantitative methods, thus providing an in-depth insight into food enterprises’ efforts to reduce their production waste and use their resources more efficiently. The main data collection methods used for the study were secondary data research, discourse analysis, case studies, and focus group interviews. The analysis of the food waste management applications in the European countries’ food sub-sectors leads to the conclusion that since the national initiatives and success factors vary between the countries, it is important to invent such national food waste management systems that are economically justified and technically available for all enterprises regardless of their food waste production volumes. It is also necessary to raise awareness of the strategies that food industry employers, employees, and consumers can use to reduce their waste and thus promote a waste minimization culture in Europe. Doi: 10.28991/ESJ-2022-06-03-08 Full Text: PDF

Cenospheres are hollow particles in fly ash, a by-product of coal burning, and are widely used as a reinforcement when developing low-density composites called syntactic foams. This study has investigated the physical, chemical, and thermal properties of cenospheres obtained from three different sources, designated as CS1, CS2, and CS3, for the development of syntactic foams. Cenospheres with particle sizes ranging from 40 to 500 μm were studied. Different particle distribution by size was observed, and the most uniform distribution of CS particles was in the case of CS2: above 74% with dimensions from 100 to 150 μm. The CS bulk had a similar density for all samples and amounted to around 0.4 g·cm−3, with a particle shell material density of 2.1 g·cm−3. Post-heat-treatment samples showed the development of a SiO2 phase in the cenospheres, which was not present in the as-received product. CS3 had the highest quantity of Si compared to the other two, showing the difference in source quality. Energy-dispersive X-ray spectrometry and a chemical analysis of the CS revealed that the main components of the studied CS were SiO2 and Al2O3. In the case of CS1 and CS2, the sum of these components was on average from 93 to 95%. In the case of CS3, the sum of SiO2 and Al2O3 did not exceed 86%, and Fe2O3 and K2O were present in appreciable quantities in CS3. Cenospheres CS1 and CS2 did not sinter during heat treatment up to 1200 °C, while sample CS3 was already subjected to sintering at 1100 °C because of the presence of a quartz phase, Fe2O3 and K2O. For the application of a metallic layer and subsequent consolidation via spark plasma sintering, CS2 can be deemed the most physically, thermally, and chemically suitable.

The current study introduces porous ceramic materials fabricated from cenospheres through spark plasma sintering. The investigation delves into the impact of sintering temperature, mould diameter (20 and 30 mm), and cenosphere size on the resulting material properties. Notably, sample shrinkage initiates at 900 °C and demonstrates an upward trend with temperature escalation, while a larger mould diameter contributes to sample shrinkage. Elevated sintering temperature leads to increased apparent density across various sample series, such as CS 63–150 µm in a 20 mm mould (0.97 to 2.3 g/cm³ at 1050–1300 °C), CS 150–250 µm in a 20 mm mould (0.93 to 1.96 g/cm³ at 1050–1200 °C), and others in different mould sizes. Total porosity decreases from 61.5 % to 3.9 % with a rising sintering temperature (1050 to 1250 °C), while open porosity starts decreasing at lower temperatures. Closed porosity peaks in samples sintered at 1150 °C. Furthermore, an increase in sintering temperature from 1050 to 1300 °C boosts the compressive strength of CS 63–150 samples in a 20 mm mould from 11 MPa to 312 MPa. These findings align with the Rice model, illustrating an exponential relationship between compressive strength, material porosity, and fully dense material compressive strength. [ABSTRACT FROM AUTHOR]

To protect their population during pandemic outbreak, countries apply several preventive restrictions and even shut down their economies to slow the spread of the coronavirus. Since food supply chains in developed countries are complicated and dependent on their external suppliers, these restrictions cause not only economic but also social tension. The limited access to raw materials, packaging material and labour force result in the increasing prices of food products, which forces the population to refuse from quality food products. In the European Union food supply chains, which are negatively affected by protectionist elements and COVID-19 restrictions, the room for manoeuvre of Latvia’s small open economy is limited. The current paper analyses the impact of COVID-19 crisis on global food industry, providing a deeper insight into the case study of Latvia meat supply chains’ experience in overcoming pandemic risks. The research outcomes lead to the conclusion that although COVID-19 impact during first breakout has not caused unexpected and serious consequences for the meat sector companies, the main internal and external risks are associated with further uncertainty and instability in the EU markets. Based on extensive analysis of meat sector specifics, the authors have summarized the recommendations for meat sector companies to better prepare for further potential pandemic situations. Doi: 10.28991/esj-2021-01257 Full Text: PDF

Nowadays, students expect that their university will not only provide a valuable source of practical knowledge for them, but will also be ready to offer appropriate distance learning opportunities both on a daily basis to diversify and enrich the study process experience and during global pandemic crises, which will probably be the reality of their lives in the next decades. The novelty and topicality of this study is justified by the need to assess the COVID-19 pandemic impact on the European Union higher education system and its adaptability to switch from traditional to remote study forms. The objectives of the study were: 1) to analyse the need to improve digital skills in the European Union by investigating the achievements of the Digital Economy and Society Index; 2) to assess the current digital environment of Latvian public universities and conduct an in-depth study of the digital environment of Latvia University of Life Sciences and Technologies. The research methodology is based on the desk study, social survey, comparative analysis and logical construction research methods. The results of the study revealed the digital gap that still exists between the more developed Nordic European countries and the less developed Southern and Eastern European countries. However, detailed analysis of the situation in Latvia leads to the conclusion that Latvian higher education institutions have significantly increased the amount of digital content in both external and internal communication systems and can offer competitive educational services that comply with the contemporary education requirements.

Several viewpoints have been reported regarding the effect of temporary cements, different surface pretreatment protocols before adhesive cementation, and predictive factors. This in vitro study tested if temporary cement, pretreatment of the tooth surface, the size of enamel or dentine influence adhesive cementation to zirconia ceramics. Twenty premolars were prepared for determination of enamel and dentin area, bond strength test and failure analysis. The samples were divided into two groups: untreated prior adhesive cementation (n = 10) and with temporary cementation done, pretreated prior adhesive cementation (n = 10). Zirconia overlays (Katana Zirconia STML) were cemented on the grounded flat teeth surfaces using Panavia V5. An additional six premolars underwent dentine tubule analysis with SEM to detect temporary cement residues after temporary cementation on an untreated tooth surface (n = 3) and on a pretreated surface (n = 3). The independent sample t-test was used to compare the two groups and the means of the total tooth, dentin or enamel areas did not differ significantly between the untreated and pretreated specimens. The mean tensile bond strength was significantly (p = 0.005) higher in the pretreated specimens (337N) than in the untreated ones (204N). The overall multivariable linear regression model with three predictors (surface pre-treatment, enamel area and dentine area) was significant (p = 0.003), among which the size of enamel was the strongest predictor (β = 0.506; p = 0.049), followed by the pretreatment effect (β = 0.478; p = 0.001) and the size of dentin area (β = −0.105; p = 0.022).

Recently, there is a growing interest in investing in ways that might eliminate global warming; therefore, a number of studies promote the idea of ESG investing. The current study presents the latest discourses on the interpretation of investment and the role of social aspects in terms of investing in ESG. The topicality of the particular study is justified by the fact that food sector investors and other market participants use ESG information through ESG ratings, which, among social factors, include on-the-job training as an important indicator of a company’s sustainability. This study was based on a mixed-methods methodology that combines qualitative and quantitative research methods in consistent methodological steps. Based on the research of a wide range of scientific literature and the results of focus group interviews with industry practitioners, the authors have explored ESG implementation issues in European food sector enterprises to identify how food sector companies can strengthen their ESG performance by developing practical on-the-job training in waste management. This study has posed a research question: What skills should be integrated in on-the-job training programs in contemporary waste management in food industry enterprises? The research results present a systematized structure that integrates explicit and tacit knowledge, skills and competence that were acknowledged as topical in developing on-the-job training programs for food industry enterprises.

Introduction: Phenylketonuria (PKU) is an inborn error of metabolism characterized by pathogenic variants of the phenylalanine hydroxylase (PAH) gene with a resulting accumulation of phenylalanine (Phe) to neurotoxic levels. Diagnosis of PKU in the Latvian population began in 1985 and the present study's aim was to evaluate the available data on all PKU patients in Latvia. Materials and methods: The medical records of 116 - DNA sample was available in 110 patients (102 nonrelated individuals) diagnosed with PKU in Latvia were obtained. Phe concentrations were measured in dried blood spots. Genomic DNA was analyzed for pathogenic variants in the PAH gene. Biochemical data were available through follow-up visits of the 83 patients. Results: In 97% of patients (99 of 102), pathogenic variants were detected on both alleles. With an occurrence of 69.6%%, the most common pathogenic variant was the severe pathogenic variant p.Arg408Trp. The available data for 83 patients revealed that metabolic control was better in younger age groups and worse in adults. Conclusion: Latvia exhibits a relatively homogeneous pool of disease-causing PKU alleles with a high prevalence of the classical severe form of PKU. Dietary compliance in all patients' groups is lower than expected, especially it is poor in adult age group.

The objective was to compare marginal defects and evaluate discoloration for adhesively cemented veneers in vitro when using two cement removal techniques. Twenty premolars were prepared with chamfer and borders in enamel. IPS e.max CAD veneers were cemented using Panavia V5 and divided in two groups (n = 10): cement excess removed with a probe after tack-curing for 3–5 s, or cement excess removed with a brush, then completely polymerized. All teeth were stored in alginate gel until micro-CT examination. Scanning was performed twice: directly after cementation and after thermocycling (5000 cycles, between 5 and 55 °C). To analyze discoloration, teeth were colored using 0.5% basic fuchsine and examined under a stereomicroscope. Depth of dye infiltration was scored 0 (no discoloration) to 5 (discoloration along the entire margin). Statistically significant differences of cement defects before thermocycling were reported, where brushing showed more defects than probing (p = 0.0161). After thermocycling, the defects increased for both groups. Extensive discoloration was the most common (55.56%) when removing excess by probing; by brushing, 90% of the specimens exhibited slight discoloration (p = 0.008). Regression analysis showed no relationship between type of defect and degree of discoloration. Removing cement with a brush causes more marginal defects, however less discoloration after thermocycling.

Green hydroxyapatite ceramics were obtained by cold uniaxial and isostatic pressing of hydrothermally synthesized powders, pure hydroxyapatite and hydroxyapatite doped with Ag+, Cu2+ and Zn2+ ions. The ceramics were conventionally and microwave sintered and analyzed by Fourier transform infrared spectroscopy, field emission scanning electron microscopy, X-ray diffraction analysis, and energy-dispersive X-ray spectroscopy. The effect of doping on the mechanical properties of the obtained hydroxyapatite/tricalcium phosphate ceramics was examined by comparing their average grain size, porosity and values of the hardness and fracture toughness. The results showed that doping with Cu2+ ions caused the lowest porosity of the ceramics and the highest values of hardness and fracture toughness. The ceramics obtained from hydroxyapatite doped with Ag+ and Zn2+ ions exhibited worse mechanical properties due to the higher porosity even in the case of microwave sintering, which provide denser ceramics than conventional sintering.

This research aims to explore the acceptance of unconventional food products that convey creative solutions for sustainable food production and consumption. This paper presents the first stage results of an extensive Baltic Sea region's population survey organized to understand how innovative food products' creators could better enhance the link between sustainable products and different segments' customer acceptance. In scope of this study, the authors focused on youth market segments, who are known for their adventurous and experimental eating habits. The authors hypothesized that products that have been created to comply with socially responsible and sustainable food products' requirements face resistance from the youth who do not view them as superior to conventional ones. The cross-sectional study utilized mixed-method methodology, combining qualitative and quantitative approaches, including a literature review, in-depth focus group interviews, and comparative analysis using normal distribution assessment and sentiment classification. The research findings indicate that while the youth acknowledge the social and environmental benefits of innovative food products, they remain hesitant to adopt them personally. Therefore, it is vital for innovative food creators to understand the biases and behaviors of young consumers, ensuring transparency about product contents, motivating them to embrace new consumption models, try unconventional foods, and highlight the personal and societal advantages of purchasing these items. [ABSTRACT FROM AUTHOR]