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Comparision of regeneration of Scots pine \{Pinus sylvestris L.\} in Myrtillosa and Hylocomiosa forest types after shelterwood cuttings 全文
2020
Rums, O., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Straupe, I., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Zdors, L., Latvian State Forest Research Inst. Silava, Salaspils (Latvia)
The aim of the study is to determine how successful the initial growth of naturally grown and planted pines is after performing the shelterwood cutting. The research includes tree count and height analysis in Myrtillosa and Hylocomiosa forest types with different regeneration methods in 2018. A total of 10 sites were arranged for the research, each site having 4 sample plots. All naturally regenerated and planted pine (2009, 2012 and 2013) heights were measured. Judging by the number of trees after shelterwood cutting, most sites should not be considered regenerated, additional planting or scarification of soil is required which can improve the efficiency of natural regeneration. In all the sites both in Myrtillosa and Hylocomiosa, after shelterwood cutting it was observed that the height of artificially regenerated trees is higher than the height of naturally regenerated trees, indicating the ability of planted pines to produce more rapid height increment in the first years of life, regardless of forest type. The basal area of the stand has a significant negative impact on the increment, and it indicates the need for the subsequent shelterwood cut to be performed. Although Hylocomiosa is a more fertile forest type than Myrtillosa, the height of the planted pine trees in Myrtillosa is higher than in Hylocomiosa, where, after shelterwood cutting, no sufficiently intensive agro-technical tending has been performed.
显示更多 [+] 显示较少 [-]Smartphone-based colorimetric determination of DPPH free radical scavenging activity in vegetable oils 全文
2020
Vucane, S., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Sabovics, M., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Leitans, L., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Cinkmanis, I., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
Free radicals can rapidly and irreversibly oxidize various structures, including unsaturated fatty acids in vegetable oils, which affect the sensory properties. Spectrophotometry is the most widely used method for the determination of free radical scavenging activity (RSA) using 2,2-diphenyl-1-picrylhydrazyl (DPPH). Barrier to the further use of classical analytical methods to analyse biologically active compounds in foodstuffs is that equipment requires high cost and has limited mobility. One of solutions is to replace classical methods, such as spectroscopy, with smartphonebased colorimetry. Huawei P30 Lite smartphone was used for colorimetric detection. The free radical scavenging activity (RSA) in vegetable oil was detected using an application ‘Color Picker’, with image matching algorithm for red, green, and blue (RGB) model. RSA was expressed as percentage and measured by the DPPH method. The aim of the study was to determinate the total free radical scavenging activity with smartphone-based colorimetry. For the data comparison and accuracy spectrophotometer as analytical optical instrument was used. Eleven vegetable oils: sea buckthorn, sunflower, rice, macadamia nut, hemp, corn, grape, linseed, rapeseed, olive and milk thistle oils were selected for analysis. The best results with no significant differences (p is greater than 0.05) compared to smartphone-based colorimetry from spectrophotometry were determined using RG values. The poor results were detected by using B value (p is less than 0.05) and were not suitable for determination of RSA. Smartphone-based colorimetry can be used in the determination of the RSA in vegetable oils.
显示更多 [+] 显示较少 [-]α-amylase activity in freeze-dried and spray-dried honey 全文
2020
Keke, A., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Cinkmanis, I., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
Honey is a naturally supersaturated sugar solution, which tends to crystallize. The crystallization of honey can lead to unwanted fermentation that can have a negative impact to honey quality. The production of honey powder could be an alternative method to prevent honey from fermentation. Honey powder could be used as alternative substitute to liquid honey that would allow to use this product more widely in the food industry. α-amylase activity is one of the most important parameters to evaluate the quality of honey. The aim of this study was to investigate the effect of freeze-drying and spray-drying on honey α-amylase activity. Detection of α-amylase activity was carried out by spectrophotometric method. High-performance liquid chromatography was used to determine the content of hydroxymethylfurfural in the powders. The obtained results showed that both drying methods had a negative impact to the enzyme activity in the samples. The lowest activity of α-amylase (8.3 DN) was measured in the spray-dried honey powder. Concentration of hydroxymethylfurfural (HMF) in the powders did not exceed required concentration 40 mg kgE−1.
显示更多 [+] 显示较少 [-]Legal and managerial solutions of public sector authorities for preserving ecosystem services of the lakes 全文
2020
Marcinkeviciute, L., Vytautas Magnus Univ., Kaunas (Lithuania) | Vilkeviciute, J., Vytautas Magnus Univ., Kaunas (Lithuania) | Zukovskis, J., Vytautas Magnus Univ., Kaunas (Lithuania)
Although the problem of ecosystem diversity loss is of a global nature, the measures to solve it must be implemented at the national level. As a member of the European Union, Lithuania needs to have a clear position regarding the application of proposed socio-economic measures. The problems of lake ecosystem utilisation analysed in the article are based on the scientific knowledge which complies with the specifics of regional natural environment. The aim of the article is to systematize scientific knowledge about modern lake ecosystem services by explaining the fundamental adaptation patterns of ecosystems and their components. The article provides a complex assessment of the services provided by lake ecosystems, reveals management problems related to optimization of the use of lake ecosystems, presents recommendations on the improvement of legislation related to lake ecosystem services, regulations for protected areas, management plans, etc.
显示更多 [+] 显示较少 [-]Development of sustainable distribution logistics system 全文
2020
Drejeris, R., Vytautas Magnus Univ., Kaunas (Lithuania) | Samuolaitis, M., Vytautas Magnus Univ., Kaunas (Lithuania)
Sustainable development is playing an increasingly important role in today’s society, and it is essential for companies seeking to meet the needs of the market to pay increasing attention to the application of sustainable development principles in their operations. The enterprise logistics system is one of the essential activities ensuring the company’s competitiveness, which ensures timely production and quality of customer service. However, in order to integrate the principles of sustainable development into the company’s logistics system, it is necessary to develop a model that identifies the impact of sustainability on each factor of the logistics system. The paper analyses the impact of sustainable development on distribution logistics to determine which activities in distribution logistics are most responsive to sustainable development and can help determine the level of corporate sustainability. The main purpose of the model, presented in the paper, is to help the business sector integrate sustainable development principles effectively in distribution logistics, taking into account the significance of on-going factors in the system for sustainability.
显示更多 [+] 显示较少 [-]Resilience in agriculture: how can CAP direct payments impact it? 全文
2020
Zickiene, A., Lithuanian Inst. of Agrarian Economics, Vilnius (Lithuania)
The increasing frequency and magnitude of adverse meteorological events together with the growing uncertainty in the upcoming future pose more and more challenges to agriculture. Therefore, the future sustainability of agriculture will increasingly depend on its resilience, i.e. the capacity to withstand various perturbations and to recover from them. The direct payment (DP) system of the EU Common agricultural policy (CAP) is the most financed EU support scheme for agriculture; however, research on its impact on the important phenomena of resilience is scarce and fragmented. In order to fill this gap, this paper offers an extensive overview of literature and a summarized list of factors that are mentioned most often as potentially influencing the agricultural resilience. Based on this, the possible impact of DP on agricultural resilience was analysed. In this paper, it is argued that this impact is transferred mostly through changing farms’ financial capabilities as well as farmers’ attitudes and behaviour, and is both positive and negative. Such phenomena as low crop insurance uptake and decrease in productivity may be due to the overcrowding effects of direct payments. These hypotheses are being tested in a survey, conducted in the meantime.
显示更多 [+] 显示较少 [-]The change of natural landscape in Lithuania 全文
2020
Ivaviciute, G., Vytautas Magnus Univ., Kaunas (Lithuania);Kaunas Forestry and Environmental Engineering Univ. of Applied Sciences (Lithuania);Klaipeda State Univ. of Applied Sciences (Lithuania)
The purpose of this article is to carry out an analysis of the natural landscape of the Republic of Lithuania in 2004–2019. During the preparation of the article, the following scientific methods were used: literature analysis, determination and evaluation of the current situation, grouping method, comparison method, graphical method, analytical and statistical analysis methods, logical analysis. The article analyses the change of the area of natural (natural, subnatural) landscape components (natural forests, wetlands, water bodies) during the period between the years 2004 and 2019. The analysis showed that the two components of the natural landscape of the Republic of Lithuania during 2004–2019 increased: the forest area (132,849.03 ha or 6.15%) and water bodies (3,668.49 ha or 1.38%). Unfortunately, the area of wetlands has decreased by 50,990.20 ha (35.05%). During the analysed period, the natural landscape of Lithuania increased by 85527.97 ha or 3.39%. At present, it is particularly important to care for and restore valuable landscape complexes to fulfil their ecosystem functions. One of the most important challenges is to reconcile urbanization and nature conservation so as not to reduce significant areas of the country’s natural landscape.
显示更多 [+] 显示较少 [-]A survey of statistics of building fires in Latvia 全文
2020
Grants, E., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
A survey of 8985 records on all fires in Latvia in 2019 gathered by State Fire and Rescue Service was performed to find out if gathered data is suitable and complete for establishment of statistical database for fire protection engineering. The purpose of the survey is to assess suitability of provided content for further studies of the characteristic building fire occurrence probabilities in different building occupancy classes and to obtain solid background for calculations of national values of fire activation partial safety factors which could be implemented in National Annex of Eurocode 1 part 1–2. Study contains data about the total number of building fires with relevance to their occupancy types and review of recorded fire causes for residential buildings that provide overall insight on typical causes of fires in dwellings.
显示更多 [+] 显示较少 [-]Financial sector evolution and competencies development in the context of information and communication technologies 全文
2020
Arefjevs, I., BA School of Business and Finance, Riga (Latvia) | Spilbergs, A., BA School of Business and Finance, Riga (Latvia | Natrins, A., BA School of Business and Finance, Riga (Latvia | Verdenhofs, A., Riga Technical Univ. (Latvia) | Mavlutova, I., BA School of Business and Finance, Riga (Latvia | Volkova, T., BA School of Business and Finance, Riga (Latvia
The development of information and communication technologies (ICT) has a significant impact on the business model of companies operating in the financial sector. Digital transformation leads to changing existing business model rapidly, as well as necessity of developing new processes specifically related to the use of ICT in business processes, development of new products and updating existing ones. At present, changes in the demand for ICT related processes in financial sector are observed both through the development of different technologies and their applications core or ancillary processes (e.g. innovations in payment systems including crypto currencies, blockchain-assisted smart contract, credit markets and insurance including peer-to-peer lending). Based on the opportunities offered by ICT, new business models need to be developed in the financial sector to transform these capabilities into new products and services that respond to changing customer demand. The aim of research to investigate the changes taking place in financial sector in the light of developments in ICT for acquisition of necessary competencies. Research methodology includes systematic review of scientific literature, analysis of selected financial sector statistics, semi-structured industry expert interviews and statistics analysis. The empirical study is limited to the financial sector of Latvia. Although due to the global nature of the financial sector the research findings could be applied internationally.
显示更多 [+] 显示较少 [-]Theoretical and legal basis of young people’s military career in the field of national defence 全文
2020
Kreija-Gaikste, S., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Katane, I., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
Research in many countries across the world, including Latvia, shows that youth participation in national defence is a topical issue. So far, scholarly research focusing on the promotion of youth participation in national defence and the provision of career support at school age and after finishing school is scarce. Therefore, the aim of the research was to establish the basis for young people’s military career in national defence. Research results show that there is both theoretical and legal basis for young people to start a military career, already during school years. Based on the broad meaning of the concepts career and career development, young people’s self-development, self-management and self-actualisation in various fields of human activity over one’s lifetime emerge as topical issues. Such activities of various kinds may follow one another in succession or take place simultaneously, in parallel, in accordance with dual career theories. The beginning and development of young people’s military career in Latvia can occur in the context of various activities already present and available in the near future: 1) participation in the Latvian Youth Guard as a type of non-formal education, 2) acquisition of National defence training at school in the context of formal education, 3) upon reaching legal age, voluntarily joining the Latvian National Guard, which is a component of the National Armed Forces of the Republic of Latvia.
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