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Flow behavior of petrol, bio-ethanol and their blendsVojtěch Kumbár, Adam PolcarActa Univ. Agric. Silvic. Mendelianae Brun. 2012, 60(6), 211-216 | DOI: 10.11118/actaun201260060211 |
Atraktivita odvětví produkce jablek v ČRDagmar KudováActa Univ. Agric. Silvic. Mendelianae Brun. 2006, 54(3), 47-60 | DOI: 10.11118/actaun200654030047 The paper deals with evaluation of attractiveness of apple production in the Czech Republic using the Industry attractiveness evaluation matrix according to the methodology of Higgins and Vincze (1989). It identifies the key criteria for evaluation of attractiveness from five fields: market factors, competition factors, financial and economic factors, technological factors, and socio-political factors. The key criteria are described in detail and evaluated from the viewpoint of a producer operating in the apple production industry. The text comes from the papers from the field of fruit production and apple production published by Kudová (2003, 2004, 2005) and Chládková (2003). Application of these methods on other industries was applied by Žufan et al. (2001) and Tomšík, and Žufan (2004). |
Atraktivita odvětví vinohradnictví a vinařství v České republice ve fázi adaptace na jednotný trh Evropské uniePavel Tomšík, Pavel Žufan, Jiří SedloActa Univ. Agric. Silvic. Mendelianae Brun. 2006, 54(3), 101-114 | DOI: 10.11118/actaun200654030101 The paper focuses on the viniculture sector in the Czech Republic in the stage of its adaptation to the united EU-market. The period before the entrance of the Czech Republic to the EU can be characterized by an effort to develop the necessary resources for its quantitative and qualitative growth at the maximum possible level. Evaluation of this period comes from analysis of: legislature and governmental and EU laws, directives and measures, development of the area of vineyards, human resources and businesses, wine market in the Czech Republic and the European Union, financial support of winegrowing and wine-production, structure of wine production, and price of grapes. Legislature for this sector had been changed in relation to the legislature of the EU - the main impacts being in registration of vineyards, the ban on new planting. Area of vineyards was enlarged by about 7 thousand hectares, and the main focus in the near future will be directed to their renewal - because of the age of the vineyards and bad heritage from the past in terms of low investments. The size structure of business subjects changed as well. Production potential is 19.3 thousand hectares of vineyard, there is filed more than 18 thousand wine-growers and nearly 600 wine producers. There is a potential for 20 thousand jobs in this sector, and considering the limited production area of vineyards, this projects into a high influence on the character, and development level of these areas. Consumption of wine is gradually increasing (16.5 litres per habitant per year, as yet). Prices, which were found, are relatively stable in the period of focus, with differences between white and blue varieties. Whereas the financial support of winegrowing was focused on enlarging the area of vineyards, in the pre-accession period, it is redirected to the restructuring of vineyards, integrated production of grapes, and reproduction of vines, in the current period. Wine imports constantly outweigh the exports in volume and value. Prices of grapes have been stable, in the past three years, but the price in 2005 was negatively influenced by wine imports. The analysis is summarized using the industry attractiveness evaluation matrix. It evaluates the selected influences with regard to the wine-production industry, which is evaluated as not very attractive, especially due to the low profitability of winegrowers, excessive regulation, and differences in financial support in different EU-member states. |
Vliv druhu a ošetření na kvalitu a zdravotní bezpečnost travních silážíJiří Skládanka, Petr Doležal, Jan Nedělník, Hana Moravcová, Roman Poštulka, Ivo VyskočilActa Univ. Agric. Silvic. Mendelianae Brun. 2010, 58(5), 329-336 | DOI: 10.11118/actaun201058050329 The paper evaluates the quality of model silages made of wilted grass biomass and treated with silage additives. Grass species used for the production of silages were Lolium perenne, Festulolium pabulare and Festulolium braunii harvested in the first cut at the stage of earing. The assessed grass species were wilted after the cut for an identical time 36 hours (2008), resp. 24 hours (2009). The treatment was made either with a chemical preparation (formic acid, propionic acid, ammonium formate) and/or with a biological inoculant (Enterococcus faecium, Lactobacillus plantarum, Pediococcus acidilactici, Lactobacillus salivarius, cellulase, hemicellulase and amylase). The amount of the chemical ingredient was 4 l.t-1 and the amount of the biological additive was 10 g.t-1. The biomass was after wilting ensilaged in containers whose diameter and height were 0.15 m and 0.64 m, respectively. After 60 days of ensilaging, the silages were assessed for pH, organic acids content, ethanol content and acidity of water extract (AWE); organic nutrients assessed in the silages were crude fibre (CF), neutral detergent fibre (NDF), acid detergent fibre (ADF), crude protein (CP) and digestibility of organic matter (DOM). Hygienic safety was assessed from the contents of zearalenon, fumonisin and aflatoxin mycotoxins. The high (P < 0.05) dry matter (DM) content in Festulolium pabulare silages indicates that the species tends to rapid wilting. The higher DM content reflected in lower biomass losses (P < 0.05). The lowest pH values (P < 0.05) were detected in silages made of Festulolium braunii. The fact relates to the higher content of lactic acid in the prepared microsilages. The use of ensiling additives affected the quality of extracts. Namely the application of the biological additive led to the increased content (P < 0.05) of not only lactic acid but acetic acid too. Titrable acidity was not affected by the ensiling additives. As to the emanation of ethanol, heterofermentative bacteria of lactic fermentation apparently took part in the fermentation process of the silages as well. While the evaluated forage species showed differences in the digestibility of organic matter (P < 0.05), the application of preservatives did not influence the content of organic nutrients. Fumonisin was not detected at all and aflatoxins were below the level of detection. None of the assessed factors had an effect on the content of zearalenon; in spite of the fact, an apparent tendency towards a higher content of zearalenon was recorded in Lolium perenne. |
PŘÍSTUPY K HODNOCENÍ ZMĚN KAPITÁLOVÉ STRUKTURY PRŮMYSLOVÝCH ODVĚTVÍMartin Landa, Dana MartinovičováActa Univ. Agric. Silvic. Mendelianae Brun. 2010, 58(6), 259-268 | DOI: 10.11118/actaun201058060259 Capital structure is described as a relation between equity and debts while the mutual consequences among items of company's assets and resources employed as well as the cost of capital are also taken into account. Both, the theory and practice, at evaluation of approaches to capital structure are focused on creation and optimization of capital structure. Relatively less frequent approach is the analysis of a state and of changes in capital structure on the level of whole business branch. But on this basis, it is possible to investigate some "average" approaches to selection of financial resources. At capital structure optimization (the proportion between equity and debts), a wide range of criteria plays a substantial role, e.g. cost of capital, risk, expected profitability, liquidity, dividend policy. These criteria have joint effect. This way, a logic question which criteria are preferred more and which criteria are preferred less appears. The article deals with the analysis of capital structure of three branches of manufacturing industry (the branch of production of plastics, the branch of production of electric equipments, the branch of production of textile) in the years 2007-2009 with the special focus on development of financial structure, capital structure and on cost of capital. |
Indukce polyploidie u Phlox paniculata L. v in vitro podmínkáchPavel Matiska, Hana VejsadováActa Univ. Agric. Silvic. Mendelianae Brun. 2010, 58(1), 101-106 | DOI: 10.11118/actaun201058010101 The objective of this work was to find an effective method of polyploidy induction using chemomutagens, colchicine and oryzalin, in diploid cultivar of Phlox paniculata 'Fujiyama' (syn. Mt. Fuji, Fuji). Ploidy level was determined by the flow cytometry method (FCM). Two methods of treating the explants (in vitro regenerated shoots) were tested; chemomutagen infiltration from nutrient media ("the infiltration method") and dipping of the explants in a chemical mutagen solution ("the dip method"). The highest values of tetraploid (5%), mixoploid (1.67%) frequency and polyploidization efficiency (1.25) were found in explants treated with 0.2% colchicine for 24 h in the dip method. Concentrations of 10 µM oryzalin and 0.2% colchicine for 14 d were the most effective for obtaining tetraploids in the infiltration method. The results will be exploited to other P. paniculata cultivars for breeding of this species. |
VLIV MIKROVLNNÉ PLASTIFIKACE, PLOŠNÉHO SLISOVÁNÍ A VYSOKOTEPLOTNÍ ÚPRAVY NA ROVNOVÁŽNOU VLHKOST A SESÝCHÁNÍ DŘEVA SMRKU ZTEPILÉHO (Picea abies (L.) KARST.)Lukáš Merenda, Andrea NasswettrováActa Univ. Agric. Silvic. Mendelianae Brun. 2010, 58(1), 107-114 | DOI: 10.11118/actaun201058010107 The wood is heterogenous material compound from substance of cell walls and air. It is colloidal capillary-cellular material with ortogonal anisotropy (Babiak, 1976). The wood has possibility to bound liquids and gases into the structure. Due to this the wood is hygroskopic material leads to changes in dimensions and volume of wood generating at adsorption and desorption of water molecules into the wood. The dimentional changes evoked by changes in moisture content (bounded water) during shrinkage and sweeling have the biggest importance. Shrinkage is making the linear dimensions, area and volume shorter and smaller (Požgaj a kol., 1997). Hygroscopicity and dimensional instability is possible to affect by drying or modification (Horáček, 2004). |
SWOT ANALÝZA KONKURENCIESCHOPNOSTI ODVETVIA OVOCIA A ZELENINY VYKONANÁ MULTIDIMENZIONÁLNYM ŠKÁLOVANÍMEva UhrinčaťováActa Univ. Agric. Silvic. Mendelianae Brun. 2010, 58(6), 597-606 | DOI: 10.11118/actaun201058060597 We present a SWOT analysis of the competitiveness of fruit and vegetables sector carried out by multidimensional scaling. Those present in view of the original methodology and given the obtained results. Identification of criteria for distinguishing objects in a multidimensional scaling was carried out by questionnaire investigation for representative firms. Perception of indicators in groups of "strengths" and "weaknesses" refers to a holistic concept in the minds of respondents - respondents do not separate from context of each particular technology and direct components of production and trading process. This perception determines the need for holistic management concept for the development of positive industry perceived position in terms of competitiveness. Groups of "strengths" and "opportunities" are perceived relatively separately and compactly. Indicators groups "weaknesses" and "threats" are diffuse. It is considered to a greater degree of disorder in the perception of indicators, which are representatives of the negative aspects in the SWOT analysis. |
Charakteristika huminových kyselin pomocí EDXS a 13C NMR spektroskopieĽubica Pospíšilová, Naděžda Fasurová, Tibor Liptaj, Lubomír JuricaActa Univ. Agric. Silvic. Mendelianae Brun. 2010, 58(1), 139-146 | DOI: 10.11118/actaun201058010139 Determination of humic acids spectral characteristics performed fast and convenient method for their quality evaluation. Humic acids (HA) were isolated from five different soil types (Luvi-haplic Chernozem, Haplic Luvisol, Haplic Cambisol, Leptic Cambisol and Eutric Cambisol) and from compost. Basic soil characteristics were determined by commonly used methods. Fractional compositon of humus showed that humic acids content was decreasing in order: compost > Luvi-haplic Chernozem > Haplic Luvisol > Eutric Cambisol > Haplic Cambisol > Leptic Cambisol. Isolated humic acids preparations were characterized comparatively by chemical and spectroscopic methods. Elemental analysis showed the highest carbon content in Luvi-haplic Chernozem HA. The lowest carbon amount was in Eutric Cambisol. Energy-dispersive X-ray spectroscopy detected elements in situ in HA molecule. All samples contained Fe, Cu, Zn, Ti, Ca, K, S, P, Si and Br. Practically no differences in elements content between soil humic substances and compost were detected. The amount of aromatic carbon was higher in Luvi-haplic Chernozem to compare with other samples. Humic acids isolated from Cambisols, on the basis 13C NMR spectroscopic data, showed that all samples contained less aromatic carbon and significantly more aliphatic carbon. |
SLEDOVÁNÍ EROZNÍHO SMYVU PŮDY U VARIANT S RŮZNÝMI MEZIPLODINAMIBarbora Badalíková, Jan HrubýActa Univ. Agric. Silvic. Mendelianae Brun. 2010, 58(2), 27-34 | DOI: 10.11118/actaun201058020027 In a pilot experiment established in a sugar beet growing region the erosive washing away of soil was studied in the years 2006 to 2008. The area is located at an altitude of 246 m with the long-term mean precipitation of 500 mm and the mean annual temperature of 8.4 °C. The soils are classified as Chernozem, moderately heavy, loamy, with a good supply of nutrients, humus content of 2.30 % and an alkaline soil reaction. Slope gradient is 12 %, exposition is NE. To study the role of intercrops in erosion control, three variants were established after the harvest of the main crop, two variants with different intercrops and one (control) with no intercrop. These were Variant 1 with Secale cereale L. var. multicaule METZG. ex ALEF., a non-freezing intercrop, Variant 2 with cluster mallow (Malva verticillata L.), a freezing intercrop, and a control variant with no intercrop. In Variant 1 Secale cereale L. var. multicaule was desiccated with the herbicide Roundup in early spring. All the variants involved maize as the main crop. In variants 1 and 2, maize was sown in intercrop residues after seedbed preparation by Vario and a compactor. In Variant 3 maize was sown after conventional seedbed preparation. For assessment of soil conditions soil samples were taken to determine soil physical and chemical properties and water content in the soil. Soil loss by erosion was determined using specially-designed pockets. Erosive washing away of soil was monitored during the entire growing season of maize. The variants in which intercrops were used were found very effective in soil erosion control. In Variant 3 (control) without surface crop residues, the washing away of soil was recorded with each heavy torrential rain. During the all years the total amount of soil loss by erosion in this treatment was 2.25 t.ha-1. |
Vlivy nadmořskÉ výšky lokality na některé chemické, zdravotní, mikrobiologické, fyzikální a technologické ukazatele kravského mléka a senzorické vlastnosti sýrůOto Hanuš, Vladimír Černý, Jan Frelich, Marek Bjelka, Jan Pozdíšek, Jan Nedělník, Marcela VyletělováActa Univ. Agric. Silvic. Mendelianae Brun. 2005, 53(2), 19-32 | DOI: 10.11118/actaun200553020019 In general, the over sea height is cumulative factor, which can influence significantly the farm conditions. This effect consists of temperature (mean year temperature), rain (sum of rainfulls), sunshine (total period of sunshine) and so on, in terms of climate, which can influence the dairy cow keeping directly and indirectly. Direct effects can influence the welfare of dairy cows in terms of hot stress for example, which could decrease a mastitis resistance of cows or their milk yield in simply way. Indirect effects can influence the dairy cows and their milk production (milk yield and milk composition and quality) by typical kinds of forages and preserved rough fodders, by their botany composition and nutritional quality. In general it is possible to say, that increasing over sea height decreases economical efficiency of dairying. On the other hand the higher over sea height is sometimes linked with pastoral system of dairy cow rearing and nourishment and more often with possibility to ecological and biodynamical agriculture application. In the fact, the mountain and submountain localities are named as less favourable areas (LFAs) in terms of agriculture efficiency and sustainability under the Czech Republic conditions. Despite of above mentioned facts, the pastoral system of dairying plays very important role for tourism development in different countries such as Alpine or Scandinavien countries, Ireland, The Netherlands or in particular in New Zealand. |
Vliv skladování na obsah aminokyselin v hlízách bramborMonika Černá, Stanislav KráčmarActa Univ. Agric. Silvic. Mendelianae Brun. 2010, 58(5), 49-56 | DOI: 10.11118/actaun201058050049 The aim of this study was to investigate the effect of storage duration on amino acids content in potato tubers. Tubers of six cultivars were stored for 16 weeks. Crude protein was determined by the Kjeldahl method. The amino acid content was identified after acid hydrolysis; sulphur amino acids were oxidized with the mixture of hydrogen peroxide, formic acid and phenol. The essential amino acids index and chemical score was calculated. The whole egg protein was used as reference protein. The effect of storage duration and cultivar on the total amino acids content was found to be significant in all potato varieties. The level of the total amino acids contents was determined within the range of 80-87%. Similar downward trend was observed in crude protein. The essential amino acids index varied considerably among the potato cultivars, ranging from 42 to 57%. Sulfur amino acids and isoleucin were the limiting amino acids in all the investigated tubers. |
VLIV LOKALITY OŠETŘENÍ PROTI ZAVÍJEČI KUKUŘIČNÉMU (Ostrinia Nubilalis), HYBRIDU A PŘÍDAVKU SILÁŽNÍHO ADITIVA NA BACHOROVOU DEGRADOVATELNOST ŠKROBURoman Poštulka, Petr DoležalActa Univ. Agric. Silvic. Mendelianae Brun. 2010, 58(2), 175-180 | DOI: 10.11118/actaun201058020175 The ruminal degradability of starch ("RDS") is an important indicator of utilization of starch by ruminal microorganism. Degradability rate influences the starch amount that will be utilized in rumen and the amount that will be digested in abomasum. The importance of those by-pass nutrients grows up with the increasing of dairy milk production. |
INFORMAČNÍ A KOMUNIKAČNÍ TECHNOLOGIE V MALOOBCHODĚ V ČESKÉ REPUBLICEAleš Hes, Daniela Šálková, Marta RegnerováActa Univ. Agric. Silvic. Mendelianae Brun. 2010, 58(6), 143-150 | DOI: 10.11118/actaun201058060143 Besides agricultural primary production, the food industry and all other branches of the economy /services/ it is the information and communication technology used in retail that is one of the factors that markedly influence food retail. Therefore it is necessary to analyse the effect of electronic transactions that are used by food retail to attract and acquire other target groups of the consumers purchasing food. Though globally the retail companies (for ex. in Great Britain) invest in this technology heavily in order to increase their competitiveness on the market the food e-business in the Czech Republic has been more or less stagnating, though the recent years have been showing slight increase of interest in this form of shopping. This article identifies both the positive and the negative reasons of this situation. The technological level of computer network and its high accessibility proven by the fact that the vast majority of consumers can use internet for purchasing any kind of goods incl. food can be considered the positive reason. On the other hand the poor offer of food presented on the internet by retailers who - for fear of low demand for other kinds of food - focus mainly on beverages and dry food can be considered one of the negatives. The weakest point here is the timely delivery of goods in unchanged quality. Despite these facts the purchasing of food via internet can still serve well for busy or handicapped customers with limited mobility. |
VLIV POUŽÍVÁNÍ BIOPALIV NA PROVOZNÍ PARAMETRY SPALOVACÍCH MOTORŮ TRAKTORŮTomáš Šmerda, Jiří ČuperaActa Univ. Agric. Silvic. Mendelianae Brun. 2010, 58(2), 219-228 | DOI: 10.11118/actaun201058020219 Application of alternative fuels brings the social benefits in terms of reducing dependence on oil industry and its products as well as decreasing of damage of the environment together with using of natural resources, especially in field of renewable energy resources. The use of biofuels is the most important part of energy strategy in European Union, whose member states have agreed the content of biofuels will achieve 5.75% of the total energy sum of fuel for transport purposes in 2010. Operation of internal combustion engine fueled by RME brings environmental benefits as described several authors in analysis of the life cycle. The contribution deals with technical difficulties of the RME usage in internal combustion engine used in agricultural tractors. Different fuel causes different process of combustion which means changes in output power and pollution. The aim of this experiment was to determine these effects. Experimental work was divided into two parts according to various fuel systems. The first tractor was equipped with mechanical injection system, the second one was provided with common-rail fuel system. The test procedures consisted of measurement of power-torque curves where the engine load was created by Eddy current dynamometer. Exhaust gas analyzer sampled the pollution of carbon monoxide, carbon dioxide and hydrocarbons as the most important indicators of combustion process. |
Charakteristika odvětví vinohradnictví a vinařství AustrálieDagmar KudováActa Univ. Agric. Silvic. Mendelianae Brun. 2005, 53(3), 257-270 | DOI: 10.11118/actaun200553030257 The paper is focused on a description of the winegrowing and wine-production in Australia, a country, which is becoming a more and more significant producer and exporter of wine in the world, and has become a part of competitive environment of the winegrowing and wine-production industry in the Czech Republic. |
Trh vína v USA a KaliforniiHelena ChládkováActa Univ. Agric. Silvic. Mendelianae Brun. 2005, 53(6), 215-224 | DOI: 10.11118/actaun200553060215 The paper describes wine market in the United States and in the California. The paper is focused on characteristic of winegrowing, wine-production, wine-consumption and wine export too. Export of California wine is growing and wine is exported to the EU for the first. We can expect to grow of interest of our consumers too. California wine will compete in high quality and low prices. |
SLOŽENÍ A TECHNOLOGICKÉ VLASTNOSTI MLÉKA ZÍSKANÉHO Z RANNÍHO A VEČERNÍHO DOJENÍMartin Skýpala, Gustav ChládekActa Univ. Agric. Silvic. Mendelianae Brun. 2008, 56(5), 187-198 | DOI: 10.11118/actaun200856050187 Milk yield varies during lactation, following what is termed a lactation curve. ŽIŽLAVSKÝ and MIKŠÍK (1988) recorded changes in milk yield within a day, too. TEPLÝ et al. (1979) a KOUŘIMSKÁ et al. (2007) published variation within a day ± 1.10 kg in milk yield, ± 0.75 % in milk fat content and ± 0.20 % in milk protein content. Milk yield of cows can be expressed in many different ways, for instance, in kilograms per lactation or in kilograms per day. A practical parameter describing milk production is milk yield (kg) per milking. |
Statististická analýza agregátů souhrnného zemědělského účtu české republiky v období let 1998-2003Božena Bodečková, Erich MacaActa Univ. Agric. Silvic. Mendelianae Brun. 2005, 53(6), 19-32 | DOI: 10.11118/actaun200553060019 Results of the statistical analysis of the of the total economic aggregate account for the Czech Republic enabled, in addition to the quantification of its performance, also to asses the developmental tendencies of economic phenomena under study. From this point of view, the most important were the data obtained within the framework of studies on the total output of Czech agricultural industry. Among the major indicators of the production intensity, the level of intermediate consumption was explored as well. This analysis involved also an exact estimation of both gross and net added value because such an analysis enables to express the the final economic effect of agriculture within the framework of the national economy as a whole. A complex approach to the solution of these problems is presented on the base of studies on the structure of both plant and animal production and of the total intermediate consumption |
Změny fyzikálních a chemických parametrů hypertrofního rybníka po aplikaci prasečí kejdyRadovan Kopp, Jan Mareš, Andrea Ziková, Tomáš VítekActa Univ. Agric. Silvic. Mendelianae Brun. 2008, 56(2), 95-100 | DOI: 10.11118/actaun200856020095 During the years 2001 and 2002 we conducted hydrochemical monitoring of intensively managed pond to evaluate the impact of high pig slurry doses on eutrophication. Pig slurry application was carried out in colder period of the year (February-April) via tube system with sludge pump from nearby piggery. |
MĚŘENÍ HUSTOTNÍHO PROFILU NEROVNOMĚRNĚ SLISOVANÉHO DŘEVA OSIKY OBECNÉ POMOCÍ PŘÍSTROJE X - RAY DENSE - LABAleš Dejmal, Jan Šrajer, Jaroslav HrázskýActa Univ. Agric. Silvic. Mendelianae Brun. 2009, 57(5), 71-78 | DOI: 10.11118/actaun200957050071 The paper deals with the measuring of the density profile of unevenly pressed wood of European aspen (Populus tremula L.). The main aim of the work is to examine in an experimental way the possibilities of using the X - RAY DENSE - LAB laboratory equipment designed for the determination of density profiles of agglomerated and plied large-area materials. The work uses the X - RAY DENSE - LAB equipment to determine the density profile of the cross-section of unevenly pressed aspen wood, plasticized hydrothermically, without the presence of chemical substances. The work also presents calculations of the level of compression/densification in dependence on the density and it describes the factors that can influence the density profile of compressed/densified wood; at the same time, it presents the possible ways to determine the density profile in the cross-section. Further, it includes the creation of the methodology for sample preparation so that the results do not get distorted during measuring. It describes the preparation of sample pieces, the orientation of the anatomic structure, the methodology of pressing, air conditioning, sample preparation, their measuring and analysis. The paper also describes the theory and the principles of measuring with use of X - RAY DENSE - LAB and its calibration. The paper analyses the obtained results of density profiles and searches for and describes the causes of the uneven distribution of the density in the cross-section. It concludes by summarizing the results and recommending the procedure for future measuring. |
Rozdíly některých ukazatelů vlastností syrového mléka a zejména minerálního složení mezi malými přežvýkavci ve srovnání s kravami v České republiceOto Hanuš, Marcela Vyletělová, Václava Genčurová, Irena Hulová, Hana LandováActa Univ. Agric. Silvic. Mendelianae Brun. 2008, 56(5), 51-56 | DOI: 10.11118/actaun200856050051 Sheep and goat farming is returning back into the Czech Republic (CR) because of positive effects of alternative milk consumption on human health. Especially the elements Ca and Mg are important for nutrition. Paper presents the comparison of mineral milk composition of goats (White short-haired-W, n = 60), sheep (Tsigai-C, n = 60) and cows (Holstein-H, n = 36; Czech Fleckvieh-B, n = 93). Cow milk results were considered as reference. The herds were kept at altitude 260 m (H), 360 m (B), and 572 m above sea level (W, C) with total precipitation 449, 700 and 1200 mm per year and mean air temperatures 9.6, 7.0 and 3.7 °C. Bulk milk samples (4-8 animals in sample) from the first two thirds of the lactation and the winter and summer season were investigated. Goat milk freezing point differed from other species (P < 0.001), -0.6048 for C < -0.5544 W < -0.5320 H < -0.5221 °C for B. Cow milk Ca values were comparable to former results although milk yield (MY) was higher. Along lower MY the Ca was higher (1299.6 > 1172.0 mg.kg-1; P < 0.001) in B than H, similar trend was in Mg (122.0 > 107.4 mg.kg-1; P 0.05) between species were in Ni and also mostly in Cu. Iodine results differed between species but not between cow breeds (P < 0.001; 462.8 H and 434.9 B > 126.0 W and 164.2 μg.l-1 C). It could be explainable by using of I disinfection at teat treatment in cows and absence of treatment in small ruminants. Macroelements were mostly highest (Ca, P, Na, Mg) in sheep milk, with exception of K. Phosphorus values (950.1 H, 1016.9 B, 1042.6 W and 1596.7 mg.kg-1 C) in species were linked with crude or true protein and casein values. Small ruminant milk could be good source of minerals for human nutrition, especially in the case of Ca and Mg of sheep and goat milk. |
Vnímanie kvality chleba spotrebiteľomĽudmila Nagyová, Patrik Rovný, Jana Stávková, Martina Uličná, Ľudmila MaďarováActa Univ. Agric. Silvic. Mendelianae Brun. 2009, 57(3), 115-122 | DOI: 10.11118/actaun200957030115 The aim of this paper is to evaluate consumers' perception of bread quality in Slovakia. Bread belongs to essential foodstuffs and we all have it served on our table every day. |
POROVNÁNÍ VLASTNOSTÍ DŘEVA BUKU LESNÍHO Fagus sylvatica (L.) V RŮZNÉM STAVU A STUPNI DEGRADACE DŘEVOKAZNÝMI HOUBAMIJiří Holan, Blanka StávkováActa Univ. Agric. Silvic. Mendelianae Brun. 2009, 57(5), 119-130 | DOI: 10.11118/actaun200957050119 This work focus on comparison of biological degradation of wood caused by wood-decay fungi (white and brown rot). Test samples were made of European Beech Fagus sylvatica (L.). As wood-decay fungi were used Trametes versicolor (L.) Lloyd (white rot) and Serpula lacrymans (Wulf. Ex Fr.) Schroet (brown rot). Aim of this work was comparison of rate of propagation of wood-decay fungus and degradation of wood in time. After termination of the test was made comparison of intensity of degradation between both fungi species. Weights of test samples were diminishing for both groups of wood-decay fungi during three months. Moisture content increased in direct proportion with time. Compression strength in direction of wood fibers of tested samples was diminishing. Samples tested by Serpula lacrymans had the fastest decrease of compression strength after first and second week of degradation. Samples tested by Trametes versicolor had different course. Compression strength significantly decreased after first month and third month of degradation. On the other hand module of elasticity of both tested groups was diminishing already during first and second week of degradation. Generally, it is possible to say that Trametes versicolor has more significant impact on changes of mechanical characteristic of wood, because it causes degradation of all chemical constituents of wood. |
MODELOVÁNÍ OHYBOVÉHO NAMÁHÁNÍ DEMONTOVATELNÝCH NÁBYTKOVÝCH SPOJŮ METODOU KONEČNÝCH PRVKŮMilan Šimek, Petr KoňasActa Univ. Agric. Silvic. Mendelianae Brun. 2009, 57(1), 137-146 | DOI: 10.11118/actaun200957010137 Presented work focuses on bending moment stress modeling of dismountable furniture joints with a use of Finite Element Method. The joints are created from Minifix and Rondorfix cams combined with non-glued wooden dowels. Laminated particleboard 18 mm of thickness is used as a connected material. The connectors were chosen such as the most applied kind in furniture industry for the case furniture. All gained results were reciprocally compared to each other and also in comparison to experimental testing by the mean of stiffness. The non-linear numerical model of chosen joints was successfully created using the software Ansys Workbench. The detailed analysis of stress distribution in the joint was achieved with non-linear numerical simulation. A relationship between numerical simulation and experimental testing was showed by comparison stiffness tangents. A numerical simulation of RTA joint loads also demonstrated the important role of non-glued dowels in the tested joints. The low strength of particleboard in the tension parallel to surface (internal bond) is the most likely the cause of the joint failure. Results are applicable for strength designing of furniture with the aid of Computer Aided Engineering. |
ZMĚNY TUKU V PRŮBĚHU FRITOVÁNÍ A VÝSLEDNÁ KVALITA JEMNÉHO PEČIVAViera Šottníková, Klára BorutováActa Univ. Agric. Silvic. Mendelianae Brun. 2009, 57(1), 147-152 | DOI: 10.11118/actaun200957010147 The purpose of this attemt was to evaluate the influence of deep-frying fat on the quality of frying pastry and observe chemical changes of frying fat during frying. |
Vliv ochrany proti zavíječi kukuřičnému na mšice a jejich přirození nepřátelé v porostech kukuřiceVáclav Psota, Vladimír HulaActa Univ. Agric. Silvic. Mendelianae Brun. 2008, 56(1), 149-156 | DOI: 10.11118/actaun200856010149 Over the period of July to September 2005 effects of insecticide Integro with the effective substance methoxifenozide and biological preparation Trichoplus using parasitoid wasps Trichogramma evanescens and T. pintoi were evaluated in maize stands. These natural enemies of aphids were recorded in monitored fields (located in South Moravia, Czech Republic): parasitoids of genera Aphidius and Praon (Hymenopetra, Aphidiidae), predatory syrphid flies (Diptera, Syrphidae), ladybirds (Coleoptera, Coccinellidae), Orius bugs (Heteroptera, Anthocoridae), Green Lacewing - Chrysoperla carnea (Neuroptera, Chrysopidae) and spiders (Araneida). No significant difference (T = 0.003; F = 4.894; P = 0.004) in populations of aphids and their antagonists was found in the studied variants (Integro, Trichoplus). More remarkable differences were found only soon after spraying with Integro. Syrphid flies pupae decreased by 41% in the Integro variant, and by 13% in the Trichoplus variant. Ladybird larvae did not occur in the Integro variant after spraying, there where 0.12 ladybird larvae on plant in the Trichoplus variant. Number of ladybird adults increased from 0.01 to 0.53 individuals per plant in the Trichoplus variant, but from 0.03 to 0.1 individuals in the Integro variant. Number of ladybird pupae decreased from 0.32 to 0.02 pupae per plant in the Integro variant, but it has increased from 0.04 to 0.54 in the Trichoplus variant. Correlative relationship between ladybird adult growing coefficient and aphid populations in the Trichoplus variant was found. |
Obnova lesa pod výstavky dubu letního (Quercus robur L.)Jiří Libus, Oldřich MauerActa Univ. Agric. Silvic. Mendelianae Brun. 2009, 57(5), 197-204 | DOI: 10.11118/actaun200957050197 Work objective was to establish reasons to the impaired vitality of woody and herbaceous vegetation growing under standards of pedunculate oak (Quercus robur L.). The paper analyzes the influence of insolation, root competition, soil moisture content and chemical composition of soil on the growth of pedunculate oak seedlings under standards. The analyses included three standards of pedunculate oak aged over 150 years, growing at an altitude of 160 m a.s.l. Controls were plots occurring at a distance of 20 m from the standards. Conclusions following out from the analyses are as follows: The number of seedlings emerged under the standards was lower than the number of seedlings emerged in the open area. Shoot height as well as root collar diameter of seedlings under the standards were lower than in the control seedlings. Total cover of herbaceous layer and height of herbs under the standards were lower than in the open area. The impaired vitality of woody and herbaceous vegetation resulted from a great amount of the fine roots of pedunculate oak standards, withdrawing water up to the wilting point. The amount of photosynthetic active radiation (PAR) under the standards was sufficient for the growth of plants. |
OPTIMALIZAČNÍ MODEL VYUŽITÍ TĚŽEBNÍHO ZAŘÍZENÍ V LESNICKÉ PRAXIJitka Janová, M. LindnerováActa Univ. Agric. Silvic. Mendelianae Brun. 2009, 57(6), 105-112 | DOI: 10.11118/actaun200957060105 The decision support systems commonly used in industry and economy managerial practice for optimizing the processes are based on algoritmization of the typical decision problems. In Czech forestry business, there is a lack of developed decision support systems, which could be easily used in daily practice. This stems from the fact, that the application of optimization methods is less successful in forestry decision making than in industry or economy due to inherent complexity of the forestry decision problems. There is worldwide ongoing research on optimization models applicable in forestry decision making, but the results are not globally applicable and moreover the cost of possibly arising software tools are indispensable. Especially small and medium forestry companies in Czech Republic can not afford such additional costs, although the results of optimization could positively influence not only the business itself but also the impact of forestry business on the environment. Hence there is a need for user friendly optimization models for forestry decision making in the area of Czech Republic, which could be easily solved in commonly available software, and whose results would be both, realistic and easily applicable in the daily decision making. |
VLIV MIKROVLNNÉ PLASTIFIKACE, PLOŠNÉHO LISOVÁNÍ A VYSOKOTEPLOTNÍ ÚPRAVY NA MODUL PRUŽNOSTI A MEZ PEVNOSTI V OHYBU KOLMO KE SMĚRU VLÁKEN V RADIÁLNÍM SMĚRU U SMRKU ZTEPILÉHO (Picea abies (L.) KARST.)Lukáš Merenda, Květoslav NiklActa Univ. Agric. Silvic. Mendelianae Brun. 2009, 57(5), 205-212 | DOI: 10.11118/actaun200957050205 Nowadays wood modification is very-discussed and its importance is growing up. Wood plasticization alias a temporary change of wood properties makes subsequent processing possible. Plasticization is very suitable for subsequent mechanical compressing of wood. Instead steaming and boiling there is a microwave heating for wood plasticization. This kind of heating cuts down the time of plasticization from hours to seconds and also reduces energy consumption. |


