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Phytoremediation as tool for prevention of contaminant flow to hydrological systems
2018
Valujeva, K., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Burlakovs, J., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Grinfelde, I., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Pilecka, J., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Jani, Y., Linnaeus Univ. (Sweden) | Hogland, W., Linnaeus Univ. (Sweden)
This paper aims to deal with the phytoremediation approach for protection of environment and preventing the streaming of contaminant flows to hydrological systems. Phytoremediation is a cost-effective environmentally friendly clean-up technology, which uses plants and microorganisms in rhizosphere for soil and groundwater treatment. Phytoremediation is enhancing degradation of organic pollutants and improving stabilization of inorganic contaminants where plants can be used to treat soil and water polluted with hydrocarbons, chlorinated substances, pesticides, metals, explosives, radionuclides as well as to reduce the excess of nutrients. Selection of species for this type of treatment processes is based on evapotranspiration potential and ability to bioaccumulate contaminants. The project entitled “Phytoremediation Park for treatment and recreation at glassworks contaminated sites” (PHYTECO) aimed at cross-sector international partnership. The challenge of project was to develop remediation strategy where negative consequences from centuries long anthropogenic influence are turned to be something positive – development of the recreation park from the glass dump. New “Knowledge in Inter Baltic Partnership Exchange for Future Regional Circular Economy Cooperation” (PECEC) project is sequential continuation.
Показать больше [+] Меньше [-]Computational fluid dynamics pressure wave and flow rate analysis of intake runner design in internal combustion engine
2018
Banis, K., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
This paper investigates the effect of intake runner design on pressure wave propagation and reflection in sparkignited internal combustion (IC) engine. These events are known to leave a noticeable influence on the overall engine performance therefore the aim of this study is to evaluate how changes in intake runner geometry affect pressure oscillations and volume flow rate. Time-dependent computational fluid dynamics (CFD) analysis was carried out to determine how these changes affect the pressure oscillations during a full engine cycle at constant crankshaft speed. Steady state CFD analysis at constant pressure differential was carried out to evaluate the effect on volume flow rate. The simulations were carried out in SolidWorks Flow Simulation environment. Honda CRF450R motorcycle engine was used to define the initial conditions and basic intake runner design. Intake air speed at port entrance cross-section was calculated based on engine parameters and operating speed. The average pressure values with respect to physical time were measured and graphed across the intake port opening cross-section. Six different intake runner designs were compared. It was concluded that the runner taper angle has influence on pressure wave-length but internal geometry (steps, curvature and taper angle) has influence on volume flow rate. It was observed that cylindrical intake runner design produced an increase in pressure wave-length but a cylindrical section of the intake runner with a stepped transition to tapered extension produced a slight increase in pressure wave amplitude.
Показать больше [+] Меньше [-]Conceptual design of modular multi functional agricultural mobile robot
2018
Pecka, A., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Osadcuks, V., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
In order to improve competitiveness in today’s business environment, farmers also have to think about the rapid technological development in their enterprises. The most important factor that can positively influence the progress of the agricultural sector is the application of modern, efficient and labour-saving technologies at the various stages of crop growing and processing. Introduction of robotics in the farming processes emerges as one of the options. Current state of technologies allows only a few tasks processed by robots to be technologically and economically viable; the most relevant example is lawn mowing robots. One of the issues that prevent widespread use of robots in agriculture is that there are still no regulations or standards in the robotic sector for the industry to allow each robot manufacturer to follow them, such as mountable equipment communication protocols, dimensions of chassis and body, control systems including sensors and actuators etc. Each robot developer chooses his own approach and interpretation in robot protocols and modules. This article presents a conceptual design of mobile robot “Formica 01” for various agricultural applications. A prototype of the proposed design has been developed and in the article various cases of its usage on strawberry fields have been described.
Показать больше [+] Меньше [-]Survival of pathogens in high pressure processed milk
2018
Liepa, M., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Baltrukova, S., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia);Institute of Food Safety, Animal Health and Environment BIOR, Riga (Latvia) | Zagorska, J., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Galoburda, R., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
The aim of the study was to assess the ability of pathogens metabolic repair from injury within 10 days of refrigerated storage of milk after high pressure treatment. Two pathogenic strains – Listeria monocytogenes ATCC 7644 (LM) and Escherichia coli ATCC 25922 (EC) were inoculated in ultrahigh-temperature treated (UHT) milk at concentration of about 107 CFU mLE-1 and treated at 400, 500, 550, and 600 MPa for 15 min with inlet temperatures 20 °C, and then stored at 4 ± 2 °C to evaluate survival and growth of pathogens. By increasing the applied pressure, an increased rate of the pathogens’ inactivation was achieved. After 10 days of storage, milk treated at 400 MPa showed growth over 3.5 log CFU mLE-1 of L. monocytogenes and 1.7 log CFU mLE-1 of E. coli. In 550 MPa and 600 MPa treated milk samples after 8 and 10 days of storage colony formation occurred (3 CFU mLE-1 (550 LM) and 2 CFU mLE-1 (550 EC, 600 LM and 600 EC)). Although high pressure treatment is effective method for reducing of pathogenic bacteria, the metabolic repair from injury of bacterial cells in milk during storage should be considered.
Показать больше [+] Меньше [-]High pressure effect on the sensory and physical attributes of pork
2018
Sazonova, S., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Galoburda, R., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)) | Gramatina, I., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Straumite, E., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
High-pressure processing (HPP) is typically used for the microorganism inactivation, which provides safety and prolonged shelf life of meat and meat products. However, for consumers along with safety, it is important to have good sensory properties, which is a combination of tender and juicy meat with an intense meat flavour. These attributes may change because of the high pressure processing; therefore, the aim of the study was to evaluate the effect of HPP on sensory and physical attributes of pork upon processing at 300 and 600 MPa at room temperature for 1 and 15 min. After HPP the processed pork samples were cooked within the package in a water bath. Colour of cooked pork did not differ among samples. Moisture content of samples decreased with the increased processing time. Sensory evaluation revealed that HPP treatment did not influence the colour and flavour of cooked pork irrespective of treatment parameters applied in the current study. The panellists indicated that increased pressure made pork samples drier and tougher, thus changing such sensory attributes as juiciness and chewiness, which are important for meat palatability. The correlation found between chewiness determined by sensory analysis and toughness determined by Warner-Bratzler shear device suggested this instrumental method as a better tool when compared to the instrumental texture profile analysis (TPA).
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 [-]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 [-]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 [-]Barbarea arcuata as a potentially expansive species in agricultural landscapes in Latvia
2018
Rurane, I., University of Latvia, Riga (Latvia). Botanical Garden;University of Latvia, Riga (Latvia);Daugavpils Univ. (Latvia) | Roze, I., University of Latvia, Riga (Latvia)
The distribution and abundance of Barbarea arcuata (Opiz ex J. et C. Presl) Rchb. were investigated throughout the territory of Latvia. The field survey was carried out to estimate the abundance patterns, and the herbarium materials were used to compile a distribution map. In total 411 localities were recorded in the period from 2015 to 2017. The species has been commonly found on roadsides, which accounts for 66% of the localities. Seventeen percent of the localities occurred in grasslands, 10% – in croplands, 4% – in fallows, 2% – on road embankment slopes, and 1% – on railway embankments. The highest density of B. arcuata were found in new fallows where it forms large populations. Whole field localities account for 5% of the total localities. Medium-sized stands are found in about 20% of localities and are mostly found in grasslands, roadsides, as well as croplands which include cereal fields and oilseed rape fields. Individual specimens are mostly found on roadside habitats and grasslands and account for 75% of the total number of localities. As dominant weed species it is found on fields of oilseed rape, cereal fields and fallows. Herbarium data and the Institute of Biology, University of Latvia lists of species show that B. arcuata distribution was frequent during the period from 1970 to 2014.
Показать больше [+] Меньше [-]Amino acids content in triticale grain depending on meteorological, agrotechnical and genetic factors
2018
Jaskiewicz, B., Institute of Soil Science and Plant Cultivation – State Research Inst., Pulawy (Poland) | Szczepanek, M., UTP Univ. of Science and Technology, Bydgoszcz (Poland)
The field studies were conducted in the years of 2011 and 2014 at the Experimental Station in Osiny, Poland. Triticale (Triticosecale) is a valuable fodder cereal with a high nutritional value of grains. It can also gain importance as a consumer cereal, providing the body with the necessary amino acids. The aim of the study was to determine the influence of precipitation and temperature conditions in the harvest year, agronomic factors (intensive or integrated type of production) and the percentage of cereals in crop rotation (50, 75 and 100%) on the amino acid content of two winter triticale cultivars (‘Pizarro’ and ‘Pigmej’) as well as to determine the nutritive value of the protein: chemical score (CS) and essential amino acid index (EAAI). Our studies have shown that although the amino acid content of winter triticale is strongly genetically determined, it also depends on weather and agrotechnical factors. Precipitation and temperature factors had the biggest effect on the tyrosine (Tyr) content. The contents of essential and non-essential amino acids in triticale grains and EAAI value were higher under intensive technology, with 50% of cereal grains in the crop rotation, and in the traditional cultivar ‘Pizarro’ as compared to the dwarf one ‘Pigmej’. The most important amino acids that limit the quality of protein in the grain are lysine (Lys) and tryptophan (Trp). Using intensive technology, reducing the cereal percentage of cereals in the crop rotation and selecting a proper cultivar, it is possible to maximize the content of the desired essential and non-essential amino acids in the triticale grains, and thereby improve their feed and consumer value.
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