Уточнить поиск
Результаты 901-910 из 2,008
Sanitary state of naturally and artificially regenerated Picea abies (L.) H.Karst young stands in Oxalidosa
2018
Miezite, O., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Ruba, J., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
In Latvia, P.abies (L.) H. Karst stands occupy about 18% of the total forest area (3.01 million) forming pure and mixed stands. Regardless of the main goals, productivity of the future forest stands must be preserved; therefore, it is very important for forest management to identify risk factors. P.abies often suffers from various risk factors. The aim of the research was – to assess the sanitary state of Picea abies (L.) H. Karst in Oxalidosa, where the area of forest stands has been restored both anthropogenically and naturally. Selected young stands are located in Limbazi district of Latvia. Empirical data was collected in 5 spruce stands with the total area of 9.2 ha in Oxalidosa. In total, 67 sample plots were installed with radius of 3.99 m, measuring 799 trees. Diameter was measured for all trees in the sample plot. For sanitary state of P.abies young stands characterization damage caused by biotic factors was assessed visually after four-point scale: health tree (0), minor damage to 25% (1), moderately damaged 26 – 50% (2), severely damaged or dried – from 51% (3). Damage caused by P.abietina and browsing was found in several stands, while damage produced by P.abietina larvae was detected only in one pure stand. Occurrence of browsing damage is 10 – 28%, while damage intensity – 7.7 – 21.8%. There are significant differences between occurrence of browsing damage (p=0.001) and also between damaged tree damage intensity (p=0.003). Nature of browsing damage depends on the size of pure and mixed stand area, the location in forest massif and adjoining territory.
Показать больше [+] Меньше [-]The relation of green infrastructure and tourism in urban ecosystem
2018
Straupe, I., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Liepa, L., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
Green infrastructure (GI) is a strategically planned network of high quality natural and semi-natural areas and provides a range of ecosystem services and protects biodiversity in urban settings. It is very important to increase understanding of the role of GI from a scientific and a socio-economic perspective. The main goal was to understand and assess the ways that tourists use from experiencing urban green infrastructure in the cities they visit. An interview questionnaire survey took place among tourists of the following countries and cities: Latvia (Riga and Jelgava) and Portugal (Lisbon and Faro). The questionnaire includes perception, psychological aspects and preferences, behaviour and activities and general questions as well as biographical information about tourists. The study represents that no significant differences have been found between respondent groups in Latvia and Portugal. The results of the survey show that in future there is a need to improve the linkage between GI and social-cultural activities in cities. Therefore, studies for tourists’ perceptions, preferences and uses of GI will provide the alternative management approaches for urban planning and tourism development in future.
Показать больше [+] Меньше [-]Density of wood of pine-tree and spruce in the mixed mature forests of the north-west Russia boreal zone
2018
Danilov, D., Leningrad Scientific Research Inst. of Agriculture ''Belogorka'', Belogorka village, Gatchina district, Leningrad region (Russian Federation) | Belyaeva, N., Saint-Petersburg State Forest Technical Univ. named after S.M. Kirov (Russian Federation);Leningrad Scientific Research Inst. of Agriculture ''Belogorka'', Belogorka village, Gatchina district, Leningrad region (Russian Federation) | Zaytcev, D., Saint-Petersburg State Forest Technical Univ. named after S.M. Kirov (Russian Federation);Leningrad Scientific Research Inst. of Agriculture ''Belogorka'', Belogorka village, Gatchina district, Leningrad region (Russian Federation)
The influence of coniferous stand composition on the density of pine (Pinus sylvestris) and spruce (Picea abies) wood is considered in this work. Processing of a large quantitative material of wood cores with the use of the ANOVA and rank analysis made it possible to reveal the influence on the macrostructure of wood of the quantitative representation of pine and spruce in the stand. In the pine part of the stand, the correlation of the wood density with the zones of early and late xylem is weak or medium. There is no wood density correlation with the width of the annual ring for stands with different shares of pine. In pine-prevailing stands with a share of pine 80% – 100%, there is a weak but reliably straight relationship between wood density and the size of late wood zone and an inverse relationship with early zone of xylem. For forest stands with a smaller part of pine participation, the relationship between these indicators is medium and reliable. For spruce, we observe a close relationship between the density of xylem and the parameters of its macrostructure in all its variants of participation in mixed coniferous plantations. In most of the studied mixed stands, the density of wood in spruce is not significantly differentiated and more homogeneous.
Показать больше [+] Меньше [-]Variation of organic matter concentrations in stream water in manure fertilized fields
2018
Miseviciene, S., Aleksandras Stulginskis Univ., Akademija, Kauno reg. (Lithuania)
The article provides the research data on the variation of organic matter in the Jaugila Stream, which flows through drained fields fertilized with organic fertilizers. The aim of the research was to determine the effect of manure application in drainage basin to the changes of organic matter concentration in the Jaugila Stream. Water samples for chemical analysis were taken once a month from the drainage water and the river. The samples from the river were taken upstream and downstream manure fertilized fields and the drainage water – from the outlets of the drainage system, which drains the fertilized area. Water analysis was performed by the Analytical Laboratory of Chemical Analysis of the ASU Water Research Institute. BOD7 was determined by titrimetric method. The research has shown that a greater impact on the increase of BOD7 concentrations in the Jaugila Stream was due to the stream water, saturated with the organic matter, flowing from the upstream areas, rather than the drainage water flowing into this stream from manure fertilized area. The assessment of BOD7 concentrations according to the water quality requirements for surface waters determined that in most cases the water of the Jaugila Stream, both in above and below fertilized areas, was in a very good or good ecological status. The impact of manure fertilized areas on the organic matter concentration in the stream was determined to be minimal, as the statistical analysis of the data has shown that the difference between BOD7 concentrations above and below fertilized areas is negligible.
Показать больше [+] Меньше [-]Food research opportunities and challenges: methods in food safety and functional food development: a review
2018
Karus, A., Estonian Univ. of Life Sciences, Tartu (Estonia) | Karus, V., Estonian Univ. of Life Sciences, Tartu (Estonia)
Large amounts of waste and by-products which are suitable for further use are generated in the food production chain. Globally, one-third of the food produced virtually becomes waste, in total 1.3 billion tonnes per year. The livestock sector is experiencing new challenges in the food and feed supply chain and waste valorization and there is a considerable diversity in animal origin food processing systems and broad knowledge base of expertise across Europe. However, due to local food production peculiarities, there is a considerable discrepancy in the waste management and processing methodology. An increasing amount of different novel feed and new functional food is available. These new products require a proper authentication and health and safety verification. Available know-how is increasing exponentially and therefore the potential for new and old bioactive component production from various currently poorly used materials is huge. Similarly, our knowledge about threats and food/feed safety is increasing. It is crucial to keep the balance between these processes. There are also several obstacles in data harmonization (data collection, used methodologies and reliability) and in data quality (lack of the comparability and completeness). The aim of the paper is to summarize the challenges in food research related to latest developments in methods.
Показать больше [+] Меньше [-]The current status and future perspectives of lactobionic acid production: a review
2018
Sarenkova, I., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Ciprovica, I., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
Lactobionic acid is a high value added compound industrially produced through energy intensive chemical synthesis, which uses costly metal catalysts, like gold and platinum. In the next years, biotechnological production of lactobionic acid can be supposed to take the full transition to the manufacturing stage. Productivity of lactobionic acid by microbial production can be affected by various factors – choice of microorganism and its concentration, supply of oxygen, temperature, substrate, cultivation method, pH and aeration rate. The aim was to review research findings for lactobionic acid production as well innovative and efficient technology solutions for self-costs reducing. Whey was recommended as a cheap and suitable substrate for the lactobionic acid production. Whey processing has been advised with Pseudonomas teatrolens in 28 °C and in pH 6 to 7 for yielding the highest productivity. The increasing commercial importance urges the progression of schemes for lactobionic acid biotechnological manufacturing.
Показать больше [+] Меньше [-]Quality of specialty coffee: balance between aroma, flavour and biologically active compound composition: review
2018
Laukaleja, I., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Kruma, Z., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
Specialty coffee, according to Specialty Coffee Association of America (SCAA) standards, is coffee which has been standardized from the coffee plantation process until its delivery to the consumer, in compliance with all quality standards, to highlight the characteristics of the beverage. With increasing coffee consumption, more attention is focused not only on the flavour and texture of the drink, but also on the impact of coffee on health. The beneficial effects of coffee on human health are mainly based on a wide range of biologically active components. The coffee composition of the biologically active compounds and flavour compounds are influenced differently by almost all technological processes. The aim of this review was to summarize recent scientific developments about composition of aroma, flavour and biologically active compounds in specialty coffee and evaluate the best possibilities to balance health promoting and flavour attributes. Specialty coffee mainly focuses on fruity, floral, sweet and acidic notes in coffee, which are opposite to phenolic compound aroma characteristics during roasting process. In conclusion, roasting temperature significantly influences all biologically active compounds and important aroma, flavour volatiles in coffee. All compound concentration, except coffee melanoidins, decreases during roasting process. Light-medium roast level could provide stability among floral, fruity aroma, flavour notes and biologically active compounds (phenolic compounds and coffee melanoidins) in coffee.
Показать больше [+] Меньше [-]Radiodensity of medial coronoid process in dogs
2018
Veksins, A., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Kozinda, O., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
The aim of this study was to detect radiodensity of a medial coronoid process of elbow joints with a medial coronoid disease and normal elbow joints in dogs. The study includes 91 large and giant breed dogs at the age from 6 to 30 months. Medial coronoid disease was diagnosed in 65 dogs and 26 dogs had normal elbow joints. Computed tomography was performed with Philips MX – 16 CT scanner and imaging data analysis performed using Horos v.2.2.0 software. CT technical data included 140 kVp, 250 mAs, 1 second rotation time and 0.75 slice thickness. The density of a medial coronoid process (MCP) was measured by two unrelated measurement methods. The study describes Hounsfield unit values in different areas of MCP in normal elbow joints and in medial coronoid disease affected joints. In 91.8% cases, MCP subchondral sclerosis observed with MCP fragmentation or fissure. We conclude that both bone density measurement methods are suitable for veterinary diagnostic imaging and can be used to evaluate canine elbow joints.
Показать больше [+] Меньше [-]Impact of inulin on production of methane, carbon dioxide and gastrointestinal canal functionality in calves
2018
Jonova, S., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Ilgaza, A., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)) | Grinfelde, I., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Zolovs, M., Daugavpils Univ. (Latvia)
Ruminants produce a large amount of methane (CH4 ) and carbon dioxide (CO2 ) in their foregut. These gases cause greenhouse effect. There are a lot of studies about different feed additives which can reduce the production of greenhouse gases in ruminants. Prebiotics can also change the amount of bacteria in animal gastrointestinal tract and reduce the occurrence of diarrhoea. The aim of this study was to test whether the prebiotic inulin affects the production of CH4 and CO2 in calves’ rumen and whether it affects the bacteria count in the rumen fluid and bacterial overgrowth in intestines. We used the flour of Jerusalem artichoke (Helianthus tuberosus L.) containing 50% of inulin. Approximately fifty days old, Holstein Friesian crossbreed calves were used in this study. Eight were in the control group, 8 received 12 g of flour and 8 received 24 g per day. On the 28th and 56th day of the research, we measured the amount of CH4 and CO2 in calves’ rumen took rumen fluid samples for bacterial analysis and urine to measure the level of phenol and indican. We concluded that adding the flour of Jerusalem artichoke at doses 12 g and 24 g did not significantly impact the production of CH4 and CO2 in calves’ rumen, the prebiotic inulin may suppress the growth of anaerobic microorganisms in the rumen at concentration 12 g of inulin reaching 56th day of experiment. The amount of phenol and indican in calves’ morning urine did not correlate with the faecal consistency of calves.
Показать больше [+] Меньше [-]Assessment of the immunogenicity and protective effectiveness of Refluvac® in mice challenged with a pandemic A/H1N1 influenza
2018
Nurpeisova, A., Kazakh National Agrarian Univ., Almaty (Kazakhstan) | Kassenov, M., Research Inst. for Biological Safety Problems, Gvardeyskiy settlement, Zhambyl Oblast(Kazakhstan) | Makbuz, A., Kazakh National Agrarian Univ., Almaty (Kazakhstan) | Sansyzbay, A., Research Inst. for Biological Safety Problems, Gvardeyskiy settlement, Zhambyl Oblast(Kazakhstan) | Valdovska, A., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Khairullin, B., Research Inst. for Biological Safety Problems, Gvardeyskiy settlement, Zhambyl Oblast(Kazakhstan)
This article describes the results of a pre-clinical study of immunogenicity and effectiveness of an inactivated pandemic vaccine (Refluvac®) on model mice. Mice received two 0.5 ml intraperitoneal inoculations with an interval of 14 days in three doses: containing 10.0, 5.0 and 2.5 μg HA (hemagglutinin) per animal. As a comparator preparation, the study used a semi-finished product (SP) vaccine diluted with phosphate buffered saline (PBS) to obtain HA concentrations of 5 μg and 10 μg. For a control group, the study used PBS as the negative control. We determined the vaccine’s protective effectiveness level by analysing its response in animals challenged with a pandemic А/California/7/09 (Н1N1) pdm09 virus. We assessed the immunogenicity of the vaccine by examining the mean geometric titre (GMT) of antibodies against the influenza virus as measured by hemagglutination-inhibition test (HAI). In the course of testing the GMT, we noted a dependence of the concentration of antibodies in serum on the vaccine’s antigen load. The highest GMT was observed in the group of mice vaccinated with a HA load of 10.0 μg – it amounted to 278.6 (95% CI, 135.6 to 572.4). We established a high tolerability of the vaccine tested. Our study shows that Refluvac® yields a high degree of protectivity against influenza A/H1N1 and prevents clinical signs, death or accumulation of influenza virus in the organs of vaccinated animals. There were deaths and clinical signs including general depression, hypodynamia and anorexia in the negative control group. The results of our study were used for the clinical study of the first Kazakhstan produced Refluvac® vaccine against pandemic A/H1N1 influenza virus.
Показать больше [+] Меньше [-]