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Sustainable pig and poultry nutrition by improvement of nutrient utilisation – A review

Nachhaltige Schweine- und Geflügelernährung durch Steigerung der Nährstoffnutzungseffizienz – Eine Übersicht

Karl Schedle

nutrient availability. Nevertheless, knowledge of the effect of feed treatments on the modification of nutrient availability seems to be very important when calculating precise and sustainable diets for pigs and poultry. The nutrient availability of feedstuffs for pigs and poultry varies widely ( Sauvant et al., 2004 ; NRC, 2012 ). Possible reasons for such a high degree of fluctuation include all those factors that interfere with the utilisation of nutrients, thus limiting their use particularly in the nutrition of pig and poultry. These factors, e.g. the anti

Open access

Z. Kledyński, P. Falaciński, A. Machowska, J. Dyczek and Ł. Kotwica

References 1. ASTM C379-65 Specification for fly ash for use as a pozzolanic material with lime. 2. M. Brandt (ed.), “Utilization of fly ashes from circulating fluidal bed combustion in construction concrete”, Pol Acad of Sci Com of Civil Eng, Poland, 2010 (in Polish). 3. S. Diamond, “Cement pastes microstructure - an overview at several levels. Proc. of a Conf. on Hydr Cem Paste: their structure and properties”, Sheffield, 1976. 4. EN 12390-3: Testing hardened concrete. Compressive strength of

Open access

R. Jame, V. Zelená, B. Lakatoš and Ľ. Varečka

Abstract

Five bacterial isolates were tested for their ability to generate hydrogen during anaerobic fermentation with various carbon sources. One isolate from sheep rumen was identified as Escherichia coli and four isolates belonged to Clostridium spp. Glucose, arabinose, ribose, xylose, lactose and cellobiose were used as carbon sources. Results showed that all bacterial strains could utilize these compounds, although the utilization of pentoses diminished growth yield. The excretion of monocarboxylic acids (acetate, propionate, formiate, butyrate) into medium was changed after replacing glucose by other carbon sources. Di- and tricarboxylic acids were excreted in negligible amounts only. Spectra of excreted carboxylic acids were unique for each strain and all carbon sources. All isolates produced H2 between 4—9 mmol·L−1 during the stationary phase of growth with glucose as energy source. This value was dramatically reduced when pentoses were used as carbon source. Lactose and cellobiose, starch and cellulose were suitable substrates for the H2 production in some but not all isolates. No H2 was produced by proteinaceous substrate, such as blood. Results show that both substrate utilization and physiological responses (growth, excretion of carboxylates, H2 production) are unique functions of each isolate.

Open access

Gregor Izrael, Juraj Bukoveczky and Ladislav Gulan

Utilisation of Modeling, Stress Analysis, Kinematics Optimisation, and Hypothetical Estimation of Lifetime in the Design Process of Mobile Working Machines

The contribution deals with several methods used in the construction process such as model creation, verification of technical parameters of the machine, and life estimation of the selected modules. Determination of life cycle for mobile working machines, and their carrying modules respectively by investigation and subsequent processing of results gained by service measurements. Machine life claimed by a producer is only relative, because life of these machines depends not only on the way of work on that particular machine but also the state of material which is manipulated by the machine and in great extent the operator, their observance of security regulations, and prescribed working conditions.

Open access

Marcin Markowski

Abstract

Dynamic data transfer demands are often being a challenge for present communication networks, as they appear in unpredictable time and must be satisfied prior to deadline. Important kind are the multi-target demands occurring in task of replication, backup, database synchronization or file transferring in pear-to-pear networks. Optimal scheduling usually depends of the nature of transport network. In the paper dynamic deadline-driven multicast scheduling problem over elastic optical network is considered. Particularly, the method for improving link utilization by traffic balance for multicast demands is proposed. Few heuristic algorithms and results of experiments, proving the benefits of balancing concept are presented

Open access

Krzysztof Jesionek, Andrzej Chrzczonowski, Paweł Ziółkowski and Janusz Badur

Abstract

The paper presents thermodynamic analysis of the gas-steam unit of the 65 MWe combined heat and power station. Numerical analyses of the station was performed for the nominal operation conditions determining the Brayton and combined cycle. Furthermore, steam utilization for the gas turbine propulsion in the Cheng cycle was analysed. In the considered modernization, steam generated in the heat recovery steam generator unit is directed into the gas turbine combustion chamber, resulting in the Brayton cycle power increase. Computational flow mechanics codes were used in the analysis of the thermodynamic and operational parameters of the unit.

Open access

Michal Kopček

Abstract

The concept Industry 4.0 is a top theme of recent times. Even if it represents the so-called 4th industrial revolution its main ideas could be used also to support the education of subjects from IT and automation. Furthermore, the basic IT and web technologies inherited by this concept are very well known to students. This paper introduces the embedded webserver of PLC and the options for its optimal utilization. The web server is essentially a simple and widely well-known technology, therefore it was chosen as an example.

Open access

Nasim Sahraei Nejad and Sharghi Ali

Abstract

Content Identifying Methodology or (CIM) was developed to measure public preferences in order to reveal the common characteristics of landscapes and aspects of underlying perceptions including the individual's reactions to content and spatial configuration, therefore, it can assist with the identification of factors that influenced preference. Regarding the analysis of landscape photographs through CIM, there are several studies utilizing image analysis software, such as Adobe Photoshop, in order to identify the physical contents in the scenes. This study attempts to evaluate public’s ‘preferences for aesthetic qualities of pedestrian bridges in urban areas through a photo-questionnaire survey, in which respondents evaluated images of pedestrian bridges in urban areas. Two groups of images were evaluated as the most and least preferred scenes that concern the highest and lowest mean scores respectively. These two groups were analyzed by CIM and also evaluated based on the respondent’s description of each group to reveal the pattern of preferences and the factors that may affect them. Digimizer Software was employed to triangulate the two approaches and to determine the role of these factors on people’s preferences. This study attempts to introduce the useful software for image analysis which can measure the physical contents and also their spatial organization in the scenes. According to the findings, it is revealed that Digimizer could be a useful tool in CIM approaches through preference studies that utilizes photographs in place of the actual landscape in order to determine the most important factors in public preferences for pedestrian bridges in urban areas.

Open access

Jozef Konôpka

Od produkcie k multifunkčnému využívaniu lesných ekosystémov

Charakterizuje sa vývoj využívania lesov ako producenta dreva a zdroja nedrevných produktov. Osobitná pozornosť sa venuje verejnoprospešným (mimoprodukčným) funkciám lesov. Definuje sa multifunkčné (funkčne integrované) lesné hospodárstvo. Uvádza sa súčasná situácia v jeho realizácii, ako aj jej bariéry. Je to najmä finančná podvýživenosť lesného hospodárstva, keď až 80 % príjmov je z predaja drevnej suroviny. Navrhuje sa verejnoprospešné funkcie lesov včleniť do ekonomického mechanizmu subjektov obhospodarujúcich lesy. Tieto činnosti zabezpečovať ako riadne platené služby.

Open access

Barbora Mrázová, Markéta Martínková, Václav Martínek, Eva Frei and Marie Stiborová

Optimalization of preparation of apocytochrome b5 utilizing apo-myoglobin

Cytochrome b5 (cyt b5), a component of endoplasmic reticulum membrane, plays a role in modulation of enzymatic activity of some cytochrome P450 (CYP) enzymes. The effect of apo-cytochrome b5 on this enzymatic system has not been investigated in details, because preparation of cyt b5 as a pure protein failed in many laboratories. In order to prepare the native apo-cytochrome b5 in a large scale we utilized a protein with higher affinity toward the heme; the apo-myoglobin from the equine skeletal muscle. In the first step, we extracted heme moiety from the native myoglobin by butanone extraction. Than the effect of pH on spontaneous heme release from both proteins was investigated: purified rabbit cyt b5 as well as equine skeletal muscle myoglobin. The prepared apo-myoglobin was incubated with the cyt b5 and heme transfer was monitored as a shift of absorption maximum from 413 to 409 nm in pH varying between 3-6 (10 mM KH2PO4, pH 3-6). Here, we obtained 43 mg of the equine skeletal muscle apo-myoglobin (43% yield). The optimal pH range for heme transfer from cyt b5 into apo-myoglobin was between 4.2 and 5. Native apo-cytochrome b5 was successfully prepared using procedure described here.