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Use of automatically obtained data in the quantitative and qualitative evaluation of harvester operator training Полный текст
2024
Strubergs, Aigars | Sisenis, Linards | Sarmulis, Ziedonis
The study aims to find out the efficiency of periodic training of the harvester (cut-to-length) operator, using the automatically saved data of the harvesterʼs information system. It has been established that logging service providers and training institutions do not analyse the operatorʼs work before starting the training; therefore, the training is carried out according to certain, standard programs, without going into the previous performance of each trainee operator. The research uses data automatically saved by Ponsse harvesters during the year, obtained from Ponsse Manager. The study found that by using automatically saved data of the harvester information and performing data grouping with subsequent analysis, it is possible to determine the progress in the execution of specific stem processing operations and to identify operations where the instructor should pay increased attention during training. The research analysed the data of 3 operators, obtained while working with Ponsse harvesters in clear-cutting. In the study, it was found that operator A reduced stem processing time by 3%, labour productivity increased by 15%, and fuel consumption per l m⁻³ decreased by 14% over 3 months. Operator B, after training, saw a 20% reduction in stem processing time, a 13% increase in work productivity, and a 5% increase in fuel consumption l m⁻³ over 3 months. Operator C had a 10% increase in stem processing time, a 1% increase in labour productivity, and a 2% increase in fuel consumption l m³ after training.
Показать больше [+] Меньше [-]Forest vegetation on the island of Upursala of Lake Cirišs, Latvia Полный текст
2024
Straupe, Inga | Jansone, Diāna | Kozure, Alīna
Only less than one percent of the territory of Latvia is occupied by broadleaved (trees having relatively wide flat leaves) forests. The aim of the research is to assess forest vegetation in the island of Upursala of Cirišs Lake. The data is collected in four forest areas of the island. Totally 12 plots, each with an area of 200 m² (20 x 20 m) have been created. In each plot, the accounting of growing trees and deadwood is carried out. The vegetation is measured in each forest area – the projective vegetation cover and cover of each plant species by tree, shrub, herb and moss layer are determined. The research founds that the average stock of growing trees on the island of Upursala is 565.8 m³ ha⁻¹. The average amount of dead wood is 108 m³ ha⁻¹, it consists mainly of fallen deadwood. Totally 45 species are listed in the vegetation plots, of which seven are determinants of European broadleaved forests. The largest number of determinant species of European broadleaved forests has been observed in stands with mixed forests (aspen – small-leaved lime – pedunculate oak, aspen – Scots pine – pedunculate oak and Scots pine – Silver birch – aspen). It can be argued that these stands will become the European broadleaved forests in the future.
Показать больше [+] Меньше [-]Responses of hybrid Aspen in vitro cultures to different proportions of red and blue light Полный текст
2024
Kondratovičs, Toms | Burša, Margarita Daina | Auziņa, Magda Lote
Light is one of the most significant environmental factors affecting the growth of plants, as it is the driving force of photosynthesis. Among others, the red and blue light are the most relevant, as these spectral regions are absorbed by chlorophyll the most. In addition, red and blue light trigger specific photomorphogenic responses that allow plants to capture the available light efficiently. Accordingly, the proportion of red and blue light (R:B ratio) is considered one of the most important characteristics of light for plants, as optimal R:B provides balanced growth and photosynthesis. The aim of this study was to evaluate how the in vitro cultures of hybrid aspen (Populus tremula L. × P. tremuloides Michx.) are affected by different R:B ratios under fixed illumination intensity. We examined the growth characteristics of plantlets under wide spectrum LED luminaires with three different R:B proportions – 1:1, 7:3 and 9:1. While photosynthesis-related variables were significantly affected by light, the effect on morphology was less pronounced. Overall, increased proportions of red light decreased the photosynthetic performance of plantlets without giving significant benefits in the form of longer shoots that could be used to facilitate propagation effectiveness. Nonetheless, the effect of light treatment remains at least partially clones-specific and should be considered in case of further application for propagation purposes.
Показать больше [+] Меньше [-]Tree litter production in coniferous old-growth forests on organic soils Полный текст
2024
Bičkovskis, Kārlis | Samariks, Valters | Jansons, Āris
Canopy litterfall is a vital component of forest ecosystems, facilitating nutrient and organic carbon transfer to the soil. Understanding litterfall dynamics in forests is crucial for assessing carbon fluxes at the national level and refining carbon balance estimations. However, information about aboveground litterfall dynamics in old-growth forests remains scarce. The aim of the study was to characterize the annual litterfall carbon input in coniferous old-growth forests on drained and undrained organic soils. In total, 12 old-growth Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) H. Karst) forests stands with the age range of 146–171 years were selected. Using cone-type litter traps, we obtained data on litterfall volumes over a one-year period. Our findings reveal that old-growth forest annual carbon input from litterfall exceeds estimates of mature forest stands aboveground litterfall. In drained sites, mean annual litter carbon input reached 2.80 ± 0.29 t ha⁻¹ yr⁻¹, while in undrained sites, it amounted to 2.17 ± 0.17 t ha⁻¹ yr. Basal area and deadwood showed a close positive correlation with annual litter carbon input, underscoring the peculiarities of late successional forest stand carbon dynamics. Total stand basal area as easily measurable forest inventory parameter was the best predictor of annual litter C input for practical application.
Показать больше [+] Меньше [-]The evaluation of tan spot phenotype and the presence of necrotrophic effectors in the population of Pyrenophora tritici-repentis in Latvia Полный текст
2024
Kaņeps, Jānis | Bankina, Biruta | Moročko-Bičevska, Inga
Tan spot is an economically important disease of wheat in Latvia, but there is still insufficient information about its causal agent’s Pyrenophora tritici-repentis diversity in Latvia. The aim of this study was to evaluate the disease phenotype in the field and the possible presence of necrotrophic effectors Ptr ToxA, Ptr ToxB and Ptr ToxC in the P. tritici-repentis population in Latvia. Typical differential wheat lines ‘Glenlea’, ‘6B662’, ‘6B365’ and ‘Salamouni’ were evaluated under the field conditions in 2023 in the central part of Latvia. The highest tan spot severity was observed during the flowering stage with no significant difference between wheat genotypes. During the experiment, the typical disease phenotypes corresponding to all three known effectors were noted. Additionally, typical tan spot symptoms were determined on the resistant cultivar ‘Salamouni’, confirming the presence of new, currently uncharacterised effectors that are not compatible with the existing race model. Future studies should focus on searching for new effectors and further characterising known necrotrophic effectors, as knowledge about P. tritici-repentis and wheat interaction is still incomplete.
Показать больше [+] Меньше [-]Rosemary essential oil by hydrodistillation: SPME-GC-MS characterization Полный текст
2024
Calvo-Gomez, Octavio | Ruzibayev, Akbarali | Akramova, Rano | Salijonova, Shakhnozakhon | Gaipova, Shakhnozakhon | Khodjaev, Sarvar
Rosemary (Salvia rosmarinus) is an aromatic herb with a multitude of uses. It is both a seasoning in various dishes, and a natural remedy for several diseases mainly due to its anti-inflammatory and anti-oxidative effects. Plus, it is also used in cosmetic industry and for improving agriculture practices and helping the environment, since it may be a natural antimicrobial. It is worth noting that this plant is also grown and commercialized in Uzbekistan, thus, if added value is given to rosemary’s products, it has potential for improving living conditions and helping in the economy of local farmers and entrepreneurs. In this work, we discuss a technique for obtaining rosemary essential oil, rich in terpenes, by vacuum assisted hydrodistillation. This is a solventless environmentally friendly and safe technique that allows the obtention of an added value rosemary product where terpenes, compounds responsible for most of rosemary’s properties, are the most abundant. Two samples of locally acquired rosemary were sourced, essential oil was extracted, and characterization was then performed by Solid Phase Micro Extraction (SPME) and Gas Chromatography – Mass Spectrometry (GC-MS). As a comparison, a direct injection of a dilution of one of the essential oil samples was also performed. It was concluded that samples of essential oil obtained from both sources were entirely composed of terpenes or terpene derivatives. Besides, SPME was a superior method when compared to direct injection, since a larger number of volatiles was able to be identified.
Показать больше [+] Меньше [-]Chemometrics as an aid to quickly evaluate galactomannans through infrared spectroscopy Полный текст
2024
Calvo-Gomez, Octavio | Ruzibayev, Akbarali | Salijonova, Shakhnozakhon | Gaipova, Shakhnozakhon | Khodjaev, Sarvar | Khakimova, Zulfiyakhon | Rakhimov, Dilshod
Galactomannans, composed of galactose and mannose, may form gels and are considered safe because of their non-toxic, biodegradable, and biocompatible nature. As a result, they are widely utilized in the food industry as stabilizers and thickeners. Among galactomannan producing species, guar gum and locust bean gum are particularly important due to their economical relevance. Guar gum and locust bean gum are often adulterated with cellulose gums like xanthan gum and carboxymethyl cellulose (CMC). Adulteration of galactomannans with other gums may introduce uncertainties regarding functionality and complicate quality control, posing a potential problem for the food industry. Among the different techniques which have been used for determining and characterizing galactomannans, Fourier Transform Infrared Spectroscopy stands out. Especially when coupled to Attenuated Total Reflection (ATR), analyses are performed rapidly, with a minimum sample preparation, and without the need for solvent or previous extraction mechanisms. However, food is a very complex matrix that contains a high number of components which generate a multitude of spectral information and large data sets. Consequently, additional data processing tools such as chemometrics are needed to be able to draw useful information from spectra. Our goal in this work is to show how to optimize conditions for instrumental analysis by infrared spectroscopy of galactomannans and its constituent monomers and create a chemometric model where galactomannans could be differentiated as a single group. We successfully optimized the PCA model obtained after chemometric processing of infrared data through reducing dimensions by loadings selection.
Показать больше [+] Меньше [-]Inclusive rural development of territorial communities of Lviv region through financial decentralisation and territorial marketing Полный текст
2024
Bezpartochnyi, Maksym | Bezpartochna, Olesia
Ensuring inclusive rural development of territorial communities requires a comprehensive study and the use of special methods and tools. To ensure such growth, it is advisable to apply financial decentralisation and territorial marketing. The aim of the study is to determine the level of inclusive rural development of territorial communities of Lviv region. The study is based on the analysis of the budgetary indicators of rural territorial communities of Lviv region, a study of the political, economic and social inclusion of active groups of entities of rural territorial communities of Lviv region. The budgetary indicators of rural territorial communities of Lviv region are analysed, taking into account the average values for the region and the country. Based on the results of questionnaire surveys of active groups of entities of rural territorial communities of Lviv region, the level of political, economic and social inclusion is determined. The research identified indicators of political, economic and social inclusion that shape the perceptions of active groups of entities on further improvements aimed at enhancing inclusive rural development of territorial communities. The results of the research show that the level of inclusive rural development of territorial communities of Lviv region is above average. Prospects are aimed at ensuring permanent monitoring of the integrated index of inclusive rural development of territorial communities as an indicator of the efficiency of budgetary funds (financial decentralisation) and meeting the needs of active groups of entities of rural communities (territorial marketing) in Ukraine.
Показать больше [+] Меньше [-]Measurement of sustainable entrepreneurship – benefits in a BREEZE: A review Полный текст
2024
Bormane, Santa | Tiuncika, Lasma
When it comes to moving towards sustainable entrepreneurship, a knowledge-based economy is starting to affect companies and how they are managed. It is relevant for researchers and entrepreneurs to evaluate different sustainability aspects and look for ways how to achieve entrepreneurship sustainability. In the past couple of decades, many indicators have been developed which measure the performance of sustainable entrepreneurship. Not all cover a sufficient basis to provide a thorough evaluation, though. The goal of the study was to evaluate the expertise in sustainable entrepreneurship among large companies with metrics identified in the latest scientific literature review. In the process of the literature review, authors identified key metrics to measure the performance of sustainable entrepreneurship and split them into six groups. They mostly focus on social, environmental, and economic performance measurement. Relatively few research results mention the importance of corporate management indicators. Thus, the key metrics are distinctive by including corporate management as a separate aspect in the performance measurement. The conceptual framework is represented by the acronym BREEZE, including 6 groups of key metrics: brand awareness and consumer behaviour, responsibility for society and employees, environmentally friendly materials, ease of use and reuse (disposal), zero waste, economic performance (approbated on focus group discussion and expert interviews). The results revealed that the expertise levels in sustainable entrepreneurship among the large companies are fair. Complementary data analyses were carried out; as a result, authors developed a self-evaluation matrix in sustainable entrepreneurship.
Показать больше [+] Меньше [-]Theoretical frameworks shaping innovative product development for the regional improvement: A multidisciplinary perspective Полный текст
2024
Braslina, Liga | Batraga, Anda | Kellerte, Katrina | Šalkovska, Jeļena | Šķiltere, Daina | Braslins, Girts
In the realm of innovative product development, a multidisciplinary and scientifically grounded approach plays a pivotal role in shaping the creation of novel solutions. As society faces complex problems and rapidly evolving needs, understanding the scientific methodologies and theories underpinning innovative product development is crucial. Research aim is to comprehensively analyse and synthesize the diverse theoretical foundations from various scientific disciplines that influence the process of innovative product development. Research methods include literature review, content analysis, and expert interviews were employed to identify and categorize relevant theoretical frameworks from various disciplines. The studyʼs key findings emphasize the importance of a multidisciplinary approach in innovative product development. The study highlights the roles of creativity, economics, and psychology in product development, stressing the need to weave diverse scientific theories into a systematic approach for user-centric solutions. The study highlights the integrative nature of innovation by elucidating the diverse theoretical foundations underpinning product development, enhancing understanding of how various scientific theories converge to drive innovation systematically. The findings underscore the importance of a multidisciplinary approach in guiding real-world product development, offering practical insights for innovators, educators, and professionals seeking to optimize the innovation process and create user-centric solutions.
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