2017, Vol. 15, No. 5
Selle kollektsiooni püsiv URIhttp://hdl.handle.net/10492/5367
Sirvi
Sirvi 2017, Vol. 15, No. 5 Kuupäev järgi
Nüüd näidatakse 1 - 20 38
Tulemused lehekülje kohta
Sorteerimisvalikud
Kirje AFLP-analysis of genetic diversity in soybean [Glycine max (l.) Merr.] cultivars Russian and foreign selection(2017) Zargar, M.; Romanova, E.; Trifonova, A.; Shmelkova, E.; Kezimana, P.Genetic diversity of 11 cultivars of soybean (Glycine max) from a VIR (N.I. Vavilov Institute of Plant Genetic Resources) collection was analyzed by the AFLP (amplified fragment length polymorphism) technique. From 18 tested primer combinations, both of them were selected for further analysis. From these two primer combinations (E32/M60 and E32/M59), 90 DNA fragments were obtained, 39 (43%) of them were polymorphic. Unique DNA fragments were found in accessions SibNIISHoz 6, Soer-4, Determinant. The Jaccard's similarity indices varied from 0.79 (between Sonata and Ugra) to 0.94 (between Ugra and Garmoniya) with an average of 0.775. Cluster analysis placed the cultivars into the several groups but separation in groups was not related to their origin or biological characteristics, even though cultivars Nordik and Soer-4 (cultivars recommended for Central Black Earth region of Russia) clustered together on the dendrogram. The obtained high values of Jaccard genetic similarity index and low level of polymorphism and differentiation illustrated a relatively low genetic diversity in our studied cultivars, which correlated with different other studies on soybean genetic diversity with AFLP-analysis.Kirje Unified client service centres for rural development and smart governance in Latvia(2017) Sunina, L.; Rivza, B.Nowadays rapid increase of technological environment allows residents to be more mobile, choose working place, different from one’s place of residence, start a new business or transfer company to rural areas, thus promoting polycentric development of a territory and increasing capacity of rural territories. It means that government should think of smart governance and service provision, providing different government services at one place. From June 2015 until December 2015, under the concept of improvement of public service system, the government of the Republic of Latvia established 75 unified state and local government customer service centres. Service centres operate on a local basis and in accordance with the uniform principles, provide customer with one place to access multiple public services. The objective of the present article is to evaluate the necessity and current activity of unified customer service centres and their contribution to smart governance of the country. The necessity for unified client service centres in the rural areas were therefore assessed with the analysis of attributable data, theory on establishment of such centres, and residents’ survey, which showed that a big part of customers of the present centres are residents of neighbouring towns and cities where the regional governmental and local institutions are located, but they are attracted by the possibility to receive all the necessary services at one time.Kirje Carbon content of below–ground biomass of young Scots pines in Latvia(2017) Jansons, Ā.; Bārdulis, A.; Ķēniņa, L.; Lazdiņa, D.; Džeriņš, E.; Kāpostiņš, R.Forest ecosystems play crucial role in global carbon cycling, therefore, increasing afforestation of agricultural land in Europe has been recognized as important contribution of carbon sequestration. In carbon reporting systems, root carbon content (CC) default value has been set to 50%. The study aimed to estimate CC in below–ground biomass and in relation to tree age in young Scots pine stands on forest and former agricultural land. The below–ground CC of young (8 to 40 years) managed Scots pine (Pinus sylvestris L.) stands growing on nutrient poor mineral soils in Latvia was carried out. In total 62 sample trees (43 in forest land, 19 in former agricultural land) were randomly selected for destructive sampling to estimate the CC within below–ground biomass. Below–ground biomass weighted mean CC was 49.7 ± 0.4%, being slightly lower than the default CC value used to calculate carbon budgets. Root fractions stump, small roots (diameter 2–20 mm), coarse roots (diameter > 20 mm)) differed (p < 0.001) in their CC. Stumps (50.6 ± 0.6%) had highest (p < 0.001) CC in the below–ground biomass, followed by coarse (49.5 ± 0.4%) and small (49.1 ± 0.4%) roots, which did not differ from each other in their CC. Results demonstrated age–dependent increase of CC (p < 0.001) from 48.2 ± 0.3% to 51.7 ± 0.5%, indicating overestimation of the default value during the first two decades, but underestimation for older trees (24 to 40 years).Kirje The advantage of Decision Support System for managing spring barley disease in Estonia(2017) Sooväli, Pille; Koppel, Mati; Lauringson, Enn; Talgre, LiinaA Decision Support System (DSS) I - Taimekaitse focusing on use of timely applied and reduced fungicide rates in control of cereal diseases has been tested in field trials since 2003 . We compared the conventional treatment and the DSS - based spray practices in 18 field trials in five agricultural locations over 7 - year period. Efficacy of the control of net blotch caused by Pyrenophora teres (Drechsler, am Drechlera teres Sacc. Shoem), the main fungal disease in spring barley has been tested to determine the economic advantage of DSS use. Compared with the conventional spray practices, the advantage I - Taimekaitse resulted in reduction of application doses by 30 to 60% of the registered rate. According to I - Taimekaitse , the fungicides were applied mainly between heading and flowering growth stages (GS 55 – 65), whereas traditional routine spraying is commonly made at booting (GS 37 – 49) . The experiment clarifies the cost - benefit of using DSS - based approach in barley disease management with average yield increase above the control in 12.8% and above the conventional treatment in 14.1%. I - Taimekaitse gave competitive disease control and average yield output reduction compared with conventional practice by 9%. In general the Treatment Frequency Index applied in conventional treatment was 0.65 and in DSS 0.41. Although the cost of treatment expense in DSS was 20% less compared with conv entional practice, the performance of conventional used spray practices was outstanding in economic return.Kirje Effect of flame weed control on various weed species at various developmental stages(2017) Mojžiš, M.; Vitázek, I.; Klúčik, J.Physical methods of weed control as solarization, mulching, use of electricity, steam and flame are now an alternative in the organically grown crop. Flame weeder already has a wide range of practical use , particularly in the cultivation of vegetables in alternative form without any chemical treatment. Compared to chemical spraying, the use of flame weeder is more expensive, but we can compensate the costs by the added value of bioproducts. The issue of costs affects the wider use of the method in practice, but it may be offset by increased e fficiency of weed control. The correct parameters of flame weeder, such as burner angle, burner height, the gas pressure, speed of weeder as well as the growth stage of the weed, weed species, climate conditions etc., can increase the effectiveness of weed control. Field and laboratory tests carried out in Canada and Slovakia were aimed at verifying the influence of parameters on the effectiveness of flame weed control.Kirje Instrumental and sensory evaluation of seven apple (Malus domestica Borkh.) cultivars under organic cultivation in Sicily(2017) Farina, V.; Gianguzzi, G.; Mazzaglia, A.; Sortino, G.In this trial we examined the quality of 7 clones belonging to more diffused apple polyclonal varietal groups, using chemical/physical and sensory analyses during two consecutive years. Galaxy, and their ameliorative clones Gala Annaglò® and Dalitoga (Gala clones) that ripen in summer, Erovan* Early Red One® and Scarlet Spur*-Evasni® (Red Delicious clone), Corail Pinova and its ameliorative clone RoHo 3615 * Evelina® that ripen in autumn were studied. Gala Annaglò® is interesting for the fruit size and peel color, Dalitoga for the early ripening and Galaxy for the crunchiness and consistency. All the Gala clones reached very high total solid soluble content confirmed by the panel judgment of the sweetness and acidity descriptors. The Red Delicious clones confirm the larger size and the high colorimetric standard of all covered red fruits; the new clone Scarlet Spur*-Evasni® reached an interesting fruit size and peel colour intensity and uniformity, and the best total solid soluble content to total acidity ratio confirmed by the sensory descriptors of acidity and sweetness. Moreover, it reached very high values of crunchiness, consistency and interesting values of apple flavour, honey flavour and fruit flavour. The ameliorative clone RoHo 3615*Evelina® was characterized by well uniform and intense coloured fruits and a more balanced total solid soluble content to total acidity ratio, and interesting values of crunchiness, consistency, apple flavour, honey flavour and fruit flavour. This study confirms the relationship between instrumental and sensory analysis.Kirje Influence of tied ridging technology on the rate of surface runoff and erosion in potato cultivation(2017) Vejchar, D.; Stehlik, M.; Mayer, V.Water management and securing good condition of soil is becoming an important factor in agriculture one of the reasons being adaptation to the increasingly frequent extremes in weather. Tied ridging technology enables to reduce significantly the loss of water and soil from arable land. The effect of a tied ridger mounted on 2-row planter and effect of 6-row tied ridger on basin renewal was tested in potato cultivation on plots of land with length of 10 m. During entire season lasting 135 days the technology helped achieve 78% of efficiency in reduction of surface water runoff and 88% of efficiency in case of soil loss. In the case of furrows with only tied ridging the water retained represented additional 15% of total water from rainfall (37.5 mm of 250 mm) over untreated furrows. In the case of basins formed in furrows with wheel trails the water retained represented 15% of total water from rainfalls in the trail. This water retained on the land would have otherwise flown off and would not have been utilized without this technology. The renewal of dams after 1/3 of the season increased significantly the efficiency of this technology. The technology of tied ridging significantly contributes to sustainable agriculture management.Kirje Anaerobic co-digestion of oil refinery wastewater and chicken manure to produce biogas, and kinetic parameters determination in batch reactors(2017) Mehryar, E.; Ding, W.M.; Hemmat, A.; Hassan, M.; Bi, J.H.; Huang, H.Y.; Kafashan, J.In order to improve the anaerobic fermentation of oil refinery wastewater (ORWW) via an appropriate nutrients pool for microbial and buffer capacity growth, a study was carried out on related anaerobic co-digestion (AcoD) with a rich organic carbon source, namely chicken manure (CM). The kinetic parameters were investigated (including cumulative biogas production, bio-methane content, retention time, and soluble chemical oxygen demand stabilisation rate) of batch AcoD experiments related to six ORWW:CM-ratio treatments (5:0, 4:1, 3:2, 2:3, 1:4, and 0:5) under mesophilic conditions. The highest soluble chemical oxygen demand removal rate was obtained for the 4:1-ratio treatment. However, the highest biogas production and bio-methane contents were achieved for the 1:4-ratio treatment. When taking into consideration the highest oil refinery wastewater portion in the AcoD mixtures and the statistical test results (LSD0.05) for the kinetic parameters, it can be seen that the 4:1-ratio treatment provided the maximum biogas production levels.Kirje Operator’s behaviour measuring methodology inside off-road vehicle cabin, operator’s focusing scheme(2017) Szabó, I.; Hushki, M.; Bártfai, Z.; Kátai, L.Operator’s workplace design takes a priority to be developed in order to reach the highest possible level of Quality, Safety and productivity. Continual improvement of the workplace is yield from studies carried out on different approaches, each approach shall keep into consideration many aspects, in this research; the results will be used for feeding the productivity aspects with valuable and reliable input data using relatively simple engineering solutions. This research is made based on literature of the accumulated knowledge from diverse fields in which different studies and analysis are made to provide the necessary input for Human Centred Design process, adopting the-state-of-the-art technologies and methodologies used for data collection and analysis for Human behaviour inside the dedicated workplace. Better understanding of the operator’s Gaze in addition to the change according to the mental and physical workloads inside the tractor cabin will lead to optimal designs for higher productivity operation.Kirje Dimethyl ether as a renewable fuel for diesel engines(2017) Zeman, P.; Hönig, V.; Procházka, P.; Mařík, J.The area of automotive fuel, or fuel components, which can be produced from biomass also includes dimethyl ether, otherwise known as DME. The issue of the use of DME as a fuel is one which has been monitored until recently. Biomass can also be used as the raw material for the production of DME. DME has therefore replaced the previously-used CFCs (chlorofluorocarbons), which are now banned for their role in dangerous levels of ozone depletion. With regard to its physical properties and combustion characteristics, it is currently expected that DME will soon apply significantly as a fuel in the municipal sector and in households, and as an alternative fuel for motor vehicles with diesel engines. DME is a suitable fuel for diesel engines and can be considered as one of the most promising diesel fuel replacements. DME is a suitable fuel for diesel engines mainly due to its low self-ignition temperature and good cetane figures. It is well miscible with most organic solvents and because the polar solvent is water-immiscible. The advantage is its high levels of purity, and its being free of sulphur, nitrogen, or metals. The physical properties of DME are very similar to the physical properties of LPG. DME requires relatively complex and costly fuel accessories, but the original compression ratio of the diesel engine is maintained. A diagram of the fuel system is illustrated in the paper. The paper analyses the dependence of vapour pressure on temperature, the dependence of the density on temperature, kinematic viscosity, the flash point, the boiling point, and the solubility of water. The objective is to evaluate this interesting energy source for applications in diesel engines.Kirje The nitrogen role in vegetables irrigated with treated municipal wastewater(2017) Montemurro, N.; Cucci, G.; Mastro, M.A.; Lacolla, G.; Lonigro, A.The reuse of treated municipal wastewater for irrigation is an established alternative to conventional water, in many countries of the world, particularly where or when water resources are extremely limited. Wastewater reuse could represent a double benefit when used in agriculture, helping overcome any lack of water resources and additionally, enriching the soil with nutrients - especially nitrogen and phosphorus. In the experimental site of Castellana Grotte (Apulia region, Southern Italy) during the 2012/13 and 2013/14 growing seasons, vegetable crops (fennel and lettuce) in succession were dripirrigated with three different water sources. Two reclaimed water streams, obtained by applying different treatment schemes to the same municipal wastewater (an effluent from the full-scale treatment plant and an effluent from the Integrated Fixed-film Activated Sludge – Membrane BioReactor pilot plant) and a conventional source, to verify the crops response and nutrient contribution through wastewater supply. Both lettuce and fennel yields were enhanced by the high content of nutrients in the effluent of one of the treatment plants, which had been operated for partial nitrogen removal. For Fennel 2013/14, wastewater-reuse led to a 54% reduction of nitrogen supply in relation to the other plots normally fertilized. In this way, an estimated saving of about 98.00 € ha-1 was achieved. Crops irrigated with treated wastewater operated for partial nitrogen removal (IMBR) showed early ripening (8 days for lettuce and 35 days for fennel 2013/14) and better quality than others not similarly-treated. However, the wastewater presented a nitrate content in excess of legal limits (35 mg L -1 , D.M. 185/2003). Therefore, the contribution of nutrients increased production (47 vs 32 t ha-1 in IMBR and WELL 2012/13 fennel theses, 53 vs 31 t ha-1 in IMBR and WELL 2013 lettuce theses and 40 vs 31 t ha-1 in IMBR and WELL 2013/14 fennel theses respectively) and improved product quality, while simultaneously saving money for chemical fertilizers not supplied, producing less environmental impact.Kirje Band structures for binding and holding of objects made from recycled metallic materials(2017) Mironovs, V.; Boiko, I.; Lisicins, M.; Zemcenkovs, V.The aim of the present research is the investigation of the possibility and effectiveness of using the band structures made from recycled metallic materials for binding and holding of objects (in particular, tubular objects as pipelines or shells). The using of band elements and structures as such is a perspective way to increase the safety and bearing capacity of the pipelines and vessels. Nowadays during repair works the outer surfaces of the mentioned objects are braided by the steel tapes, i.e. the objects are strengthened by the binding. The mentioned steel bands are specially produced for binding purpose. From the other hand after stamping of smallsize details (like the elements of supply chains for different apparatus) the metallic waste in the shape of perforated metallic tapes are received and needs to be reused in compliance with the good practice in effective resource using and recycling. The band structures for binding and holding of tubular objects, produced from the perforated metallic tape by the longitudinal profiling, multilayer and spiral winding are presented. It is proposed to apply in industry the composite band structures made from perforated metallic materials and epoxy matrix for binding and holding of tubular objects as pipelines or shells, which allows simplifying and speeding up the repair works especially in the cases of the local damages.Kirje Production and analysis of non-traditional beer supplemented with sea buckthorn(2017) Adadi, P.; Kovaleva, E.G.; Glukhareva, T.V.; Shatunova, S.A.; Petrov, A.S.In recent years, there has been a growing demand for non-traditional beer (craft) with different flavours hence the main aim of this research is to produce beer with sea buckthorns (SBT). Brewing software BeerSmith was used to design the Kölch beer. After one month of primary fermentation, SBT were sanitised and crashed before adding into the green beer. Carbonation was done using keg with 1.8 bar of carbon dioxide. Physicochemical properties, microbial load and sensory evaluation of Kölch fruit beer (KFB) were determined. All the physiochemical parameters measured were significantly (P < 0.05) influenced by the fermentation time. The pH dropped from 5.8 ± 0.1 to 3.9 ± 0.1 toward the end of the fermentation. There was no microbial growth when KFB was inoculated in the media. °Brix likewise decreases from 13.3 ± 0.43 to 3.86 ± 0.25. There was a change in the colour of the wort throughout the fermentation from 11.2 ± 0.44 to 32.5 ± 0.56 EBC. A decrease from 1.48 ± 0.02 to 0.86 ± 0.02 mg maltose per 100 ml in the reducing sugar was observed during the entire period of fermentation. A total of 32 volatile compounds were identified. All assessed sensory variables of KFB were significantly different (P < 0.05) and preferred by the panellists, however, foaminess and clarity of KFB should have to be improved. KFB showed higher DPPH radical scavenging activity as compared to other types of beer examined due to biologically active substances contributed by SBT.Kirje The effect of bedding amount on gas emissions from manure during storage(2017) Šimon, J.; Vegricht, J.; Bradna, J.One of the major agricultural pollutants of environment is manure from livestock. We focused on dairy cows kept in the barns with straw bedding commonly used in the Czech Republic. We tested the hypothesis that the amount of bedding used daily relative to the number and size of animals kept has a significant effect on the emissions of gases from manure stored in a manure pile. In the experiment, a group of 10 dairy cows of Holstein and Czech Red Pied breed was housed in a stable bedded with various amounts of wheat straw (4–10 kg/livestock unit per day). The manure was removed from the stable after 48 h and mixed was stored in cubic containers with drain floor allowing measurement of manure leachate release. For 50 days we measured weight, volume, weight of manure leachate and manure temperature. Decreasing stored manure weight can be attributed to release of manure leachate and emissions of gases, primarily water vapor, as a result of microbial activity and increased temperature in the manure during storage. Using the calculated model, we found that daily production of emissions of water vapor and other gases was related to bedding amount in a statistically significant manner (P < 0.001). The cumulative amount of gas emissions grew rapidly in all treatments. Also total amount of emissions was related to bedding amount in a statistically significant manner (P = 0.004). We also found the relationship between internal manure temperature and the logarithm of the amount of emissions produced to be statistically significant (P < 0.001).Kirje Evaluation of smart economy development in the RIGA planning region (LATVIA)(2017) Rivža, B.; Āzena, L.; Rivža, P.To evaluate the potential development of smart economy in the Riga planning region (henceforth – RPR), it is important to understand the present situation in the region, its specificity, and role in the context of provisional future trends. Two approaches have been employed in the present study to evaluate the situation on a regional level. One includes the collection and comparison of the basic economic development indicators, whereas AHP method has been used in the second approach, where 5 experts expressed their opinion on the options of potential development of smart specialisation in the RPR. RPR as a capital city region is pronouncedly monocentric, with Riga city as its socioeconomic core that develops a wide network of functional ties, and creates a home for the part of the society that works in Riga, but lives in the adjacent suburban territories – Pieriga. Traditionally the basic indicators of development include only the demographic and economic indicators. Sometimes these results are not objective, do not describe the potential for development, but clearly show the inequal social and economic situation in the region. To characterise the economic development in the RPR, we will include the economic profile data, statistical data and expert opinions on the population, regional government, state and EU influence on the development of the Pieriga region smart specialisation.Kirje Analysis of Arabidopsis defensin-like genes and ovule development during fertilization and Fusarium infection(2017) Spalvins, K.; Blumberga, D.Defensins are small, highly stable antimicrobial peptides. Many defensin-like (DEFL) peptides found in flowering plant Arabidopsis thaliana are believed to have role in either natural immunity or cell-to-cell communication during fertilization. However, little is known about the DEFL peptides and their functions during these events. The goal of this work is to investigate the genes encoding selected DEFLs by observing their expression patterns during fertilization and Fusarium graminearum infection. According to the results 4 selected genes of interest (GOI) are downregulated after fertilization and infection and mock treatments are causing degradation and delay of development in treated ovules.Kirje Effect of slurry lagoon redesign on reduction of ammonia emission during livestock manure storage(2017) Aboltins, A.; Priekulis, J.; Aboltina, B.; Melece, L.In accordance with the international and EU aims to reduce emissions of ammonia and other air pollution substances farm manure management, including its storage, especially for the animal breeding sector, is one of the most essential stages. One of the preventing steps is covering of the slurry lagoons. The most effective – hard covering can be provided only after the lagoon is constructed. The aim of the research: to develop methodology for calculations of emission reducing lagoon design volume and surface area. In the result of the theoretical research the possibilities of reducing the reflection surfaces at the same capacity of the lagoon have been discovered, as well as the changes of the reflection surface area, if instead of one lagoon several lagoons with less volume are installed and sequential filling of these lagoons is ensured. The article presents the calculation algorithms obtained during the research and recommendations for construction of low emission lagoons.Kirje Work strain predictors in construction work(2017) Roja, Z.; Kalkis, H.; Roja, I.; Zalkalns, J.; Sloka, B.The aim of this study was to predict the work strain indicators for construction workers and to work out measures for prevention of strain at work. Subjective and objective research methods were utilized in the research, including survey, work intensity measurements (Borg Scale), work strain index, fatigue index and work ability index determination, objective blood pressure and pulse measurements. Statistical analysis with significance calculations was carried out. The limitation of this study is the small number of subjects involved in the research. Subjective evaluation of fatigue index and strain index resulted in moderate and somewhat hard work heaviness categories accordingly to Borg Scale. Measurements of heart rate, blood pressure approved work strain of employees of both professions does not exceed the admissible heart rate limit during physical load. The research proved that the strongest work strain predictors were connected with psycho-social risks rather than with physical ones.Kirje Substantial factors influencing drivers’ comfort in transportation(2017) Zewdie, R.; Kic, P.Research shows that driver stress is associated with workload and fatigue, and an inappropriate microclimate in the driving cabin can have an impact on overall driver’s safety. The aim of this scientific study is to examine whether driver stress, across various urban and field drive conditions, can affect performance in a confined environment and whether the natural breathing process can also compound these effects and aggravate health hazards. This paper will address the influencing parameters associated with driver comfort of everyday job occupations in the urban communication network of Prague city public transport. In this research paper the authors will characterize cardinal components directly accountable to the safe operation elements; the concentration of carbon dioxide (CO2) and the relative humidity (Rhi) in the driving cabin, affecting the contentment of the drivers comfort while performing their duties. Similar inquiries were carried out on ventilation emphasis and air intake impact in drivers’ cabin, recommending a design to minimize safety problems associated with comfort. Data on the concentration of carbon dioxide and internal relative humidity in the respective cabins have been collected carefully for detailed analysis. This research paper is the outcome of these findings.Kirje Through economic growth to the viability of rural space(2017) Rivza, B.; Kruzmetra, M.; Zaluksne, V.Rural areas as a living space for the population has been increasingly explored in official documents of various EU institutions and in research topics. Both the documents and the research papers stress the necessity to enhance and maintain the viability of rural areas. The viability of rural areas is ensured by employment opportunities and readiness of residents for active and innovative economic activities. The paper presents an analysis of vertical and horizontal changes in entrepreneurship in the period of 2009–2015 and their effect on changes in the living space of the analysed territories in Latvia’s regions. The processes in administrative territories of regions, municipalities were analysed, as the life of residents is influenced not only by national policies but also by on-going processes in the administrative territories of local governments. The data of LURSOFT for the period of 2009–2015 and the Central Statistical Bureau for the period of 2013–2015 were used as the sources of information. The data were processed by quantitative (growth) and qualitative (structural change) statistical analysis methods. The Eurostat methodology and the methodology developed by the authors for classification of industries were employed for the analysis of structural changes in the national economy. The development level-rate matrix method was used for an in-depth examination of the research results. The research results showed that, in spite of the global economic crisis, both vertical growth and positive horizontal change took place in the national economy of all five regions of Latvia, nine cities of national significance as well as all 110 municipalities that composed the rural areas of Latvia. The authors arrived at the conclusion that, first, performance trends contributing to economic growth were observed in the rural space; second, there was no direct causal relationship between the population density and economic activity in the rural territories; third, the economic growth in the rural territories was greatly affected by the quality of local governance and local community residents’ readiness for active, innovative and inclusive activities.
