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Estimation of Unknown Object Measures in a Chemical Weighing Design with Correlated Errors
In this paper, some problems that concern the determining of unknown measurements of objects in the model of a chemical balance weighing design are presented. These designs are tested under the assumption that measurement errors are correlated and have the same variances. The relations between the parameters of a weighing design are considered from the point of view of the D-optimality criterion. We give some conditions determining the dependencies between the parameters of such designs and construction examples.
A study of the efficiency of chemical balance weighing designs
Abstract Some elements concerning the problem of determining chemical balance designs are considered. A method is presented for determining the best design in classes where no D-optimal design exists. In this case, we obtain a design that is highly D-efficient. The efficiency of such a design is presented as a function of the number of parameters and measurements, and its properties are studied. Charts showing the efficiency function for selected classes of designs are presented.
Notes on the Efficiency of Spring Balance Weighing Designs with Correlated Errors for An Even Number of Objects
In this paper, some issues regarding the efficiency of spring balance weighing designs for a selected class are presented. We give some conditions determining the relations between the parameters of such designs and construction examples.
The impact of minimum wage on automotive companies' performance
This paper aims to verify the relationship between minimum wage growth and the financial indicators of automotive companies. As a hi-tech sector, the automotive industry is usually not expected to be affected by minimum wage policies. The introduction of the minimum wage in Germany and the dynamic development of the minimum wage in Eastern European countries make it possible to assess this relationship. German, Czech, Polish, and Slovak automotive company data was obtained from the Orbis database. Panel regression models were applied to test for dependencies. The paper detects the association between the growth of the minimum wage and the increase in personnel cost, which is next to the associations with several financial indicators at the company level. The identified impact is specific to small and medium-sized companies.
The Content of Antioxidant Compounds and VOCs in Sorghum Grain Grown in Central and Eastern Europe
Sorghum is a plant belonging to the Poaceae family. It is drought-resistant and has low soil requirements. In the face of climate change, it is increasingly cultivated in Europe. Poland is a country with great agricultural potential; it is thus important to develop effective and economic methods of agricultural production, which is confirmed by the introduction of sorghum into cultivation. The aim of this study was to characterize the composition of bioactive compounds (i.e., phenolic acids, flavonoids, carotenoids, and phytosterols) and VOCs in sorghum grain of two varieties, i.e., white âSweet Carolineâ and red âSweet Susanaâ grown in the temperate climate (PÄtkowo, Poland (52°12âČ40âł N 17°15âČ31âł E)). The following tests were carried out: analysis of phenolic acids, flavonoids, carotenoids, phytosterols, antioxidant activity (ABTS), free phenolic acids (FPAs); elemental analysis; and water, fat and starch content analysis. Based on the conducted research, it was concluded that Poland has appropriate conditions for growing sorghum, as the content of bioactive (antioxidant) compounds was at a similar level to those grown in tropical and subtropical climates. Of the nine phenolic acids and seven flavonoids determined, the highest concentrations in both sorghum grain varieties were found for ferulic, p-coumaric and protocatechuic acids. The content of ferulic acid was three times higher in Sweet Caroline grains than in Sweet Susana grains. Differences in the content of these compounds may be the result of genetic differences between the Sweet Susana and Sweet Caroline varieties.
Profile of Polyphenols, Fatty Acids, and Terpenes in Henola Hemp Seeds Depending on the Method of Fertilization
Botanical varieties of hemp differ in chemical composition, plant morphology, agronomy, and industrial suitability. Hemp is popular for cultivation for the production of cannabinoid oil, fiber production, biomass, etc. The fertilization process is one of the most important factors affecting the plant, both its condition and chemical composition. So far, research has been carried out proving that hemp is a valuable source of, among others: fatty acids, amino acids, acids, vitamins, numerous micro- and macroelements, and antioxidant compounds. In this experiment, it was decided to check the possibility of harvesting hemp panicles twice in one year. The purpose of this treatment is to use one plant to produce cannabidiol oil and grain. The main aim of the research was to determine bioactive compounds in hemp seeds and to determine whether the cultivation method affects their content and quantity. Based on the research conducted, it was observed that hemp can be grown in two directions at the same time and harvested twice because its health-promoting properties do not lose their value. It was found that regardless of whether hemp is grown solely for seeds or to obtain essential oils and then seeds, the type of fertilization does not affect the content of phenolic acids (e.g., syringic acid: 69.69â75.14 ÎŒg/100 g, vanillic acid: 1.47â1.63 ÎŒg/100 g). Based on the conducted research, it was found that essential oils can be obtained from one plant in the summer and seeds from Henola hemp cultivation in the autumn, because such a treatment does not affect the content of the discussed compounds.
Biochemical Properties of Bioactive Compounds in the Oil from Polish Varieties of Camelina sativa Cultivated in 2019â2022
AbstractColdâpressed Camelina oil is a traditional oil registered as a traditional food in Poland. Camelina oil has healthâpromoting properties and high oxidative stability. This may be due to the presence of various bioactive antioxidant compounds such as carotenoids, sterols and polyphenols. Bioactive compounds content in Camelina oil depends mainly on the varieties and on the conditions under which the crop was grown therefore the aim of the research was to analyse antioxidant bioactive compounds in oil from different cultivars of Camelina sativa seeds and to determine their relationship with oil parameters.
Changes in Camelina sativa Yield Based on Temperature and Precipitation Using FDA
Camelina (Camelina sativa) is an oilseed crop of increasing importance, valued not only for its adaptability to diverse environmental conditions and potential for sustainable agriculture but also for its economic advantages, including low input requirements and suitability for biofuel production and niche markets. This study examines the relationship between camelina yield and climatic variablesâspecifically temperature and precipitationâbased on a ten-year field experiment conducted in Poland. To capture the temporal dynamics of weather conditions, Functional Data Analysis (FDA) was applied to daily temperature and precipitation data. The analysis revealed that yield variability was strongly influenced by the length of the vegetative period and specific weather patterns in April and July. Higher yields were recorded in years characterized by moderate spring temperatures, elevated temperatures in July, and evenly distributed rainfall during the early generative growth stages. The Maximal Information Coefficient (MIC) confirmed the relevance of these variables, with the duration of the vegetative phase showing the strongest correlation with yield. Cluster analysis further distinguished high- and low-yield years based on functional weather profiles. The FDA-based approach provided clear, interpretable insights into climateâyield interactions and demonstrated greater effectiveness than traditional regression models in capturing complex, time-dependent relationships. These findings enhance our understanding of camelinaâs response to climatic variability and support the development of predictive tools for resilient, climate-smart crop management.
Rate of Microelement Quantitative Changes during the Composting of Sewage Sludge with Various Bulking Agents
The composting of sewage sludge (SS) with structure-forming additives is a popular and inexpensive method for the management of biodegradable waste. During this process, a number of transformations of organic matter and nutrients occur. This study presents the rates and directions of quantitative changes in Cu, Zn, and Ni during the composting of various mixtures. The following substances were used for preparing compost mixtures: SS, sawdust, straw, and bark. These substances were mixed together in appropriate proportions as follows: C1: 45% SS + 50% sawdust + 5% straw; C2: 45% SS + 50% bark+ 5% straw; and C3: 45% SS + 35% bark + 15% sawdust + 5% straw. Single (DTPA solution) and sequential extraction methods (BCR protocol) were used for microelement mobility assessment. Compost valorization was performed in each individual composting phase. The chain relative increment analysis was used for such assessment. Additionally, the potential metal pollution in the composts was evaluated by applying the following indices: the pollutant accumulation index (PAI), heavy metal enrichment index (HMEI), and heavy metal pollution load index (HMPLI). During composting, generally, the amounts of Ni, Cu, and Zn increased in the various extracted combinations, which was independent of their susceptibility to decomposition. Despite of this, the tested composts should be considered as a source of slowly available microelements for plants. The most intense quantitative changes in metals occurred in the thermophilic phase, and the weakest changes occurred in the cooling phase. At the same time, the calculated indices indicated a lack of contamination of the composts with the analyzed metals, emphasizing their environmental safety and lack of negative impact. The bulking agents used for composting with SS did not significantly influence the intensity of the quantitative changes in the tested metals.
D-optimal chemical balance weighing designs with positively correlated errors: part II
Summary Some questions related to the problem of determining a chemical balance weighing design satisfying the criterion of D-optimality are considered. The theory is based on the assumption that the measurements are equally positively correlated and have the same variances. In this paper, we present a method of adding three measurements to a regular D-optimal chemical balance weighing designs to obtain a highly D-efficient chemical balance weighing design. The problem formulated in this way is an extension of results contained in a paper previously published in Biometrical Letters.
The Effect of Mineral Fertilization on the Content of Bioactive Compounds in Hemp Seeds and Oil
The popularity of hemp cultivation for industrial purposes has been steadily growing for many years. With the addition of products derived from these plants to the Novel Food Catalogue, maintained by the European Commission, a significant increase in interest in hemp food is also expected. The aim of the study was to determine the characteristics of hempseed, oil, and oil cake samples produced from experimental plots grown in different conditions. The research was conducted on the Henola variety, one of the newest and most popular varieties of hemp, recently bred for grain and oil. The content of bioactive compounds in grain and oil has been subjected to detailed chemical analyses in order to determine the effect of fertilization, the method of plant cultivation, and processing conditions on their quantity. The test results and the statistical analysis carried out showed a significant impact of the tested factors on the content of some of the tested bioactive compounds. The obtained results will help in the development of an effective method of cultivation for this hemp variety in order to maximize the content of the desired bioactive compounds per unit of cultivation area.