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Stalk material cutting energy
2005
Smits, M.(Latvia Univ. of Agriculture, Jelgava (Latvia))E-mail:mareksmi@llu.lv | Kronbergs, E.(Latvia Univ. of Agriculture, Jelgava (Latvia))
Systainable energy systems and food security can be obtained in rural areas by usage of renewable energy resources and development of agro-ecotechnologies. Substitution of fossil feedstock for energy and raw materials by biomass is important measure also for greenhouse gas (GHG) emission mitigation. The article presents investigation of reed biomass size reduction processes flattening and cutting. The necessity to reduce the size of common reeds (Phragmites australis) to particles smaller than 3 mm for solid biofuel production is determined by compaction properties of biomass. It was stated that unflattened reed stem cutting energy consumption is 2 times more than flattened stem cutting energy. There are no sufficient differences in the energy consumption values for single flattened reed stalk cutting with different shaped knives. The average difference is approximately 2.4 kJ square m with knife edge angles 90 deg and 20 deg.
Показать больше [+] Меньше [-]Cost efficient biodiversity production in the pastoral landscape - estimation of cost functions
2005
Nilsson, F.(Swedish Univ. of Agricultural Sciences, Uppsala (Sweden))E-mail:Frederik.Nilsson@ekon.slu.se
Same public goods can only be produced jointly with private goods. This paper focuses on the biological diversity that could be produced on semi-natural pastures through the assistance of grazing animals. The question that is being investigated is what shapes the total and marginal cost functions for biological diversity production on semi-natural pastures have if private goods are already being produced using livestock at farms near the pastures. The empirical analysis shows that a quadratic function describes the costs well and that the production is characterized by increasing marginal costs.
Показать больше [+] Меньше [-]Structural divergence of Zemgale farms
2005
Liscova, A.(Latvia Univ. of Agriculture, Jelgava (Latvia))E-mail:Anna.Liscova@llkc.lv
The results of synthesis and analysis regarding the structural diversity of farms, their differences, divergence and development in Jelgava district and Zemgale agricultural region are expanded in the article. Commercial farms and semi-subsistence farms are particularly studied on the basis of farm accountancy data.
Показать больше [+] Меньше [-]Investigation of the quality of dough with germinated grain additive
2005
Rakcejeva, T.(Latvia Univ. of Agriculture, Jelgava (Latvia))E-mail:Tatjana.Rakcejeva@llu.lv | Skudra, L.(Latvia Univ. of Agriculture, Jelgava (Latvia)) | Legzdina, L.(Latvia Univ. of Agriculture, Jelgava (Latvia))
Germinated grains are added to wheat dough with the purpose to promote the biological value of bread. As a result, a new product was obtained with a higher content of protein, fibre, B group vitamins; and vitamins C and E. The task was to investigate gluten quality changes at grain germination time, wheat dough rheological properties changes with various wheat, rye and barley amount additions, germinated for a different time. With the purpose to save maximum stability value of gluten, it was ascertained that the germination time of wheat grain could not be more than 24 hours. The best dough quality was obtained with germinated wheat grain additive. Germinated rye and barley grain additive (more than the experimentally ascertained amount) increases dough softening, decreases dough development time and dough stability. Only adding experimentally determined optimal amount of germinated grain, which promotes high quality bread, could produce dough with accepted rheological properties.
Показать больше [+] Меньше [-]Effects of gender and HCG administration on skatole levels in liver and hepatic activities of cytochromes P4502E1 and P4502A6 in pigs
2005
Zamaratskaia, G.(Swedish Univ. of Agricultural Sciences, Uppsala (Sweden))E-mail:Galia.Zamaratskaia@lmv.slu.se | Chen, G.(Swedish Univ. of Agricultural Sciences, Uppsala (Sweden)) | Lundstroem, K.(Swedish Univ. of Agricultural Sciences, Uppsala (Sweden))
Accumulation of skatole levels in porcine fat tissue is a major reason for boar taint, an objectionable odour in meat from entire male pigs. In contrast to males, female pigs do not accumulate skatole in increased amounts. Hepatic metabolism is critical for the regulation of skatole. Cytochromes P4502E1 (CYP2E1) and P4502A6 (CYP2A6) are key enzymes involved in skatole metabolism. The objectives of this study were to evaluate the effects of gender and hCG stimulation on the activities of CYP2A6. Liver samples were taken at slaughter and analyzed for skatole concentrations, and for activities of CYP2E1 and CYP2A6. It was found that female pigs expressed higher CYP2E1 activity whereas activity of CYP2A6 did not differ between sexes. Skatole levels in the liver were higher in male pigs than in female pigs. Neither skatole levels nor enzyme activities were affected by hCG stimulation. It was concluded that the incidence of boar taint may depend on both the amount of skatole reaching the liver, and the activities of enzymes involved in skatole metabolism.
Показать больше [+] Меньше [-]The dynamics of growing of bifidobacterium lactis in substrate enriched with lactulose
2005
Beitane, I.(Latvia Univ. of Agriculture, Jelgava (Latvia)) | Ciprovica, I.(Latvia Univ. of Agriculture, Jelgava (Latvia))E-mail:inga.ciprovica@llu.lv
Lactulose is recognized world-wide as one of the most clinically reliable bifidogenic factor. Lactulose is used in various types of food products (infant formula, baby food, confectionary, soft drink, milk products) and also pharmaceutically to improve hepatic encephalopathy and constipation (Mizota, 1996; Strohmaier, 1998). The object of this study was to investigate the influence of concentration of lactulose on growing Bifidobacterium lactis in milk. A bifidogenic lactor, lactulose was added (1, 2, 3, 4 and 5%) into 100g of milk. The milk samples were inoculated with Bifidobacterium lactis (BB-12, Chr. Hansen, Denmark) and incubated at 38 deg C for 16 hours. Lactulose as a prebiotic influences the growth of bifidobacteria in milk. Trends of development of acidity in the milk samples with or with out lactulose were not similar. Laboratory studies have generally shown that growth of Bifidobacterium lactis in milk depends on the concentration of lactulose. Data on the final cell count in fermented milk indicates that increasing the lactulose concentration from 2% to 3% enhanced the growth of the Bifidobacterium lactis, whereas no significant difference between lactulose concentration 4-5% and control sample was observed. Present result furthermore indicate that finding combination of prebiotic and probiotic pairs where the prebiotic would benefit the specific probiotic strain, e.g. during production and formulation into foods, is not a simple task.
Показать больше [+] Меньше [-]The effect of some ingredients on stability of butter during the storage time
2005
Vitola, I.(Latvia Univ. of Agriculture, Jelgava (Latvia))E-mail:vineta.vitola@laima.lv
The effect of some ingredients on stability of butter during its storage time has been investigated in order to better evaluate the functionality of confectionery. The research established that butter does not contain enough free fatty acids, derived as a result of hydrolysis, to decrease the number of mould and group of Enterobacteriaceae, but they hinder the growth of yeast and aerobic mesophilic and facultative anaerobic microorganisms. The quality of the products can be provided and propagation of microorganisms can be hindered by the comounds that are not traditional preservatives, such as vanilin and glucose syrop. A 10% glucose syrup additive worked as the facilitator of the development of microorganisms because it increased growth of aerobic mesophilic and facultative anaerobic microorganisms, 50% of glucose syrup additive worked as the procrastinator of the development of microorganisms.
Показать больше [+] Меньше [-]The characteristic of birch natural woodland habitats in Latvia
2005
Straupe, I.(Latvia Univ. of Agriculture, Jelgava (Latvia))E-mail:inga.straupe@llu.lv
The role of birch natural (NWH) and potential natural (PNWH) woodland habitats for maintaining of biodiversity in Latvia is described and evaluated. The analysis of the proportion of area of birch stands and natural and potential natural woodland hibitats by regions, by age structure, and by growing conditions has been done. The distribution of birch natural and potential woodland hibitats by habitat groups, as well as most often recognized habitat specialist and indicator species is described.
Показать больше [+] Меньше [-]Competence in higher education in multi-dimensional aspect
2005
Tomsons, V.(Latvia Univ. of Agriculture, Jelgava (Latvia))E-mail:Vilnis.Tomsons@llu.lv
The term "competence" has not been clearly defined in the literature. Two meanings of the term have been identified. One refers to the outputs or results of education (training), but other - to the inputs or underlying attributes needed for a person to demonstrate competent performance. Each meaning has been used to describe both individual and organizational competences. A classification of the meanings of competence is given to show that the term has several meanings depending on the purpose for which it is used. Although competence is an important concept in education, it is unclear what competence is. Constructivism is a way out of the competence confusion - we don't search for one absolute true definition, but do use the competence concept for our own purposes. At the end of article a description (definition) of competence is given. This definition is appropriate to define inputs for undergraduate programmes and to improve student's lifelong and life wide learning competences while studying undergraduate study programmes.
Показать больше [+] Меньше [-]Study course "Rural tourism" in higher educational establishments
2005
Dunska, I.(Latvia Univ. of Agriculture, Jelgava (Latvia))E-mail:inara_dunska@hotmail.com
Rural tourism is becoming more and more important in Latvia and Europe, where rural environment changes, began already more than a couple of decennaries ago. Current trends in development of tourism are favourable for lasting development of rural tourism in the whole European Union. Rural tourim in Latvia extremely popular, because it includes both recreational and cognitive elements of tourism, and takes place in countryside. It gives people a chance to become acquainted witg a country lifestyle, the process of production and be in touch with nature, be able to obtain strength and take emotional pleasure in the energy of nature. The study course "Rural tourism" is lectures both in Latvia's, and foreign higher educational establishments. This course usually is the free choice study object. The aim of the work is to observe study course "Rural tourism" aims and describe the content of this study course in higher educational establishments in Baltic States and North Europe.
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