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Rhizobium sp. – a potential tool for improving protein content in peas and faba beans
2017
Senberga, A., Latvia Univ. of Agriculture, Jelgava (Latvia) | Dubova, L., Latvia Univ. of Agriculture, Jelgava (Latvia) | Alsina, I., Latvia Univ. of Agriculture, Jelgava (Latvia) | Strauta, L., Latvia Univ. of Agriculture, Jelgava (Latvia)
Legume seed inoculation prior to sowing is a well-known practice in agriculture. Nitrogen fixation, due to the symbiotic relationship between legumes and rhizobia, improves the productivity of legumes. Rhizobia strain specificity can be observed very often, leading to differences in the total protein content. In this study two faba bean cultivars (‘Karmazyn’ and ‘Bartek’) and five pea cultivars (‘Retrija’, ‘Zaiga’, ‘Lāsma’, ‘Vitra’ and ‘Bartek’) were tested using various rhizobia strains. In addition, strain effectivity was observed in four different soil types. Overall, the protein content increase was observed after seed inoculation with Rhizobium sp. Rhizobia strain and plant cultivar interaction specification was observed. Plant cultivar appeared to have a decisive role in the formation of protein content when inoculated with Rhizobium sp. From these pilot experiments, it can be concluded that, when choosing Rhizobium sp. strains for legume inoculation, soil type also should be considered. Rhizobia has the potential to be used as a commercial preparation intended for increasing legume protein content, alongside with increased legume yield; however, different rhizobia strains should be mixed together to achieve the optimal result.
显示更多 [+] 显示较少 [-]Effect of nitrogen and sulphur fertilization on chlorophyll content in winter wheat
2017
Skudra, I., Latvia Univ. of Agriculture, Jelgava (Latvia). Faculty of Agriculture. Inst. of Agrobiotechnology | Ruza, A., Latvia Univ. of Agriculture, Jelgava (Latvia). Faculty of Agriculture. Inst. of Agrobiotechnology
Nitrogen management strategy in plant growth period based on chlorophyll content evaluation in plant can improve nitrogen usage efficiency and reduce environmental contamination. This study is aimed to determine the impact of different nitrogen and sulphur fertilizers rates on dynamics of chlorophyll content in winter wheat during vegetative growth and to determine the relationship between nitrogen and chlorophyll content and grain yield of winter wheat. Field trial involving a winter wheat (Triticum aestivum L.) variety ‘Kranich’ was conducted at the LUA Research and Study Farm Vecauce during a three-year period (2012-2015). The treatments were 0, 85, 153, 175+S21, 175 (in 2015), 187 N kg haE−1 and different nitrogen norms according to chlorophyll meter Yara N-tester (Konica Minolta Ltd.) data: 180, 150, 205 N kg haE−1 depending on the year. The results of the trial show that the maximum chlorophyll content in different plant parts was observed at the end of flowering stage. The chlorophyll content depended on the level of mineral fertilisation. The highest chlorophyll content in leaves, stems and ears was obtained by using additional sulphur in two trial years. Usage of chlorophyll meter Yara N-tester obtained the highest chlorophyll content in all analysed plant parts in one trial year. Chlorophyll content was significantly dependant on plant growth stage in stems in all trial years, in leaves in two trial years, and in ears in one year. Nitrogen fertilization significantly affected chlorophyll content in leaves and stems in one trial year. Close positive correlation was observed between grain yield and wheat plant chlorophyll content and average nitrogen concentration at the end of flowering stage in all three trial years.
显示更多 [+] 显示较少 [-]Mathematics education problems and attempts to solve them in nowadays Lithuanian school
2017
Malaukyte, I., Aleksandras Stulginskis Univ., Akademija, Kaunas reg. (Lithuania). Centre of Mathematics, Physics and Information Technology
The decreasing number of the Lithuanian residents has strong impact on the educational system: the number of pupils is decreasing, the schools are getting closed. School is considered to be the provider of educational services, so it is necessary to search, how to preserve and attract clients – pupils. The growing competition induces search for distinctiveness among the schools. According to the theory of generations of William Strauss and Neil Howe, now we have to educate representatives of generation Z, who do not like violence, restrictions, want to be distinctive and are open to the world of technologies. The teacher faces the challenge when s/he wants to convey mathematical skills to these pupils. The profile teaching followed by training based on individual curricula provided more choices for the pupils. This freedom led to the dead-end of mathematical literacy and forced to return to a compulsory national final exam of Mathematics and to change the indexes for the persons entering studies of the first cycle and integrated studies. In the article, mathematics achievements and situation in schools in Lithuania as well as the measures taken to improve mathematical literacy in the country are described.
显示更多 [+] 显示较少 [-]Mathematics admission test remarks
2016
Ideon, E., Estonian Univ. of Life Sciences, Tartu (Estonia). Inst. of Technology | Aruvee, E., Estonian Univ. of Life Sciences, Tartu (Estonia). Inst. of Technology
Since 2014, there have been admission tests in mathematics for applicants to the Estonian University of Life Sciences for Geodesy, Land Management and Real Estate Planning; Civil Engineering; Hydraulic Engineering and Water Pollution Control; Engineering and Technetronics curricula. According to admission criteria, the test must be taken by students who have not passed the specific mathematics course state exam or when the score was less than 20 points. The admission test may also be taken by those who wish to improve their state exam score. In 2016, there were 126 such applicants of whom 63 took the test. In 2015, the numbers were 129 and 89 and in 2014 150 and 47 accordingly. The test was scored on scale of 100. The arithmetic average of the score was 30.6 points in 2016, 29.03 in 2015 and 18.84 in 2014. The test was considered to be passed with 1 point in 2014 and 20 points in 2015 and 2016. We analyzed test results and gave examples of problems which were solved exceptionally well or not at all.
显示更多 [+] 显示较少 [-]Fault diagnosis of low-power three-phase induction motor
2016
Gedzurs, A., Latvia Univ. of Agriculture, Jelgava (Latvia). Faculty of Engineering
An induction motor reliability survey at an egg processing plant shows that almost 50% of the total motor failures are fan induction motors. Visual investigations of the faulty fan motors show that the main cause of the induction motor failure is air gap eccentricity. In this study, experimental tests are performed on a 1.1kW three-phase induction motor to detect air gap eccentricity and overheating of the induction motor. Heating tests show that end shield housing temperature reaches 100°C with blocked air flow from the fan, which can reduce the lifespan of the bearing. Dimension measurements of the end shield housing show that the dimensions of both tested motors back-end shields are larger than ISO tolerance grade limit. It leads to a loose fit between the housing and bearing, causing air gap eccentricity. Also, both motor back end shield housing has an out-of-round condition leading to an unbalanced magnetic pull. To detect the air gap eccentricity caused by too loose of a fit between housing bore and bearing, current Park’s vector approach is used. To measure three phase current, Hall Effect current transducers, a digital oscilloscope is used and Matlab software to process the measurement data. Results show that Park’s vector approach can be used to detect the air gap eccentricity caused by too loose a fit between bearing and housing. Therefore, the Park’s vector approach can be used to diagnose air gap eccentricity and analyse the type of the air gap eccentricity.
显示更多 [+] 显示较少 [-]The correctness problems in applying inductive statistics in economics and agriculture
2017
Jaunzems, A., Ventspils Univ. College (Latvia) | Balode, I., Aleksandras Stulginskis Univ., Akademija, Kauno reg. (Lithuania)
In the article “Professor Tinbergen’s Method” (Keynes J. M. Professor Tinbergen’s Method. − The Economic Journal. 1939. Vol. 49. No. 195) John Maynard Keynes expressed critical notes concerning insufficient scientific level of the Jan Tinbergen’s results obtained with the help of econometric methods. The conclusion of present research is that the critical appraisal of econometric applying given by John Maynard Keynes in 1939 can be completely assigned to many published in Latvia research in economics and business done by inductive statistics because scientists carelessly apply the linear regression model in absence of the knowledge a priori required by proper theorems and algorithms. Moreover, many times there is no sense even to speak about stochastic experiment because the most important condition − ceteris paribus does not fulfil, namely, economic environment is not homogeneous enough. As the result, the causal inferences derived from Regression Report are not scientifically justified. The second conclusion is that the objective criticism in econometrics applications area in order to keep the satisfactory level of scientific correctness and scientific ethics in Latvia has to be established. We also assert that the applications of inductive econometrics in agriculture are much more justified due to possibility to repeat the stochastic experiments many times in constant circumstances like in physics and mechanics. The meta-target of present article is to remind the protests of John Maynard Keynes to the careless utilization of econometric theorems and to raise a wide discussion about the problems of correctness in applying inductive statistics in economics and agriculture in Latvia.
显示更多 [+] 显示较少 [-]10. Baltic-Nordic Agrometrics Conference: Mathematics and Statistics for the Sustainable Development
2016
Vintere, A., Latvia Univ. of Agriculture, Jelgava (Latvia). Dept. of Mathematics
X Baltic-Nordic Agrometrics conference “Mathematics and Statistics Society for Sustainable Development” was held from 15 to 17 September at the Latvian University of Agriculture (LLU) in the framework of the Nordplus Higher Education 2016 project NPHE-2016/10342 “Raising awareness about the role of math skills in building specialists’ competence for the sustainable development of society”. Agrometrics is mathematics and statistics in agricultural science and studies. The aim of the X Baltic-Nordic Agrometrics conference was to exchange ideas, find out new solutions or highlight topical problems on the mathematics, statistics, informatics and physics education tendencies, practical application and research in the context of sustainable development.
显示更多 [+] 显示较少 [-]Application of statistical methods in the analysis of sentence structure
2016
Piaseckiene, K., Siauliai Univ. (Lithuania). Faculty of Technology, Physical and Biomedical Sciences
The goal of this research is to explore sentence structures expressed by parts of speech. Due to a small amount of data, a problem of sparse data has arisen, which was solved by recording the annotated sentences and considering a “framework” of a sentence made up from a verb and a noun, which was conditionally called a code. The code of a sentence is created by changing each word of a sentence by a symbol (letter or number) that encodes one or other property of that word as a constituent of the sentence. Zipf’s law describes sentences, encoded like that, rather well. If we ‘learn’ well to identify and analyze (annotate, translate, etc.) sentences of the simplest structure, we can automatically process quite a large part of text sentences. It is possible to identify at least 17% of sentences consisting of the simplest structure.
显示更多 [+] 显示较少 [-]The characteristics of extruded faba beans (Vicia faba L.)
2016
Strauta, L., Latvia Univ. of Agriculture, Jelgava (Latvia). Faculty of Food Technology | Muizniece-Brasava, S., Latvia Univ. of Agriculture, Jelgava (Latvia). Faculty of Food Technology
Faba beans (Vicia faba L.) are an excellent protein source and should be more present in human diet, but due to their long cooking time, they are rarely used. So, in order to increase the accessibility of faba beans (Vicia faba L.), experiments were carried out to obtain new food products. Extrusion-cooking was chosen as the potential thermal cooking process and two different products were obtained. One was made exclusively from faba bean (Vicia faba L.) flour, while the second one was produced with a 50% addition of wheat flour to bean flour. Protein content, size, volume mass, pH and starch content for obtained products were analysed in order to characterise the products, as well as to see the differences from non-extruded faba beans (Vicia faba L.) and obtained samples. The experiments were carried out using faba beans (Vicia faba L.) obtained at Ltd. “Pure Horticultural Research Centre”. They were milled at Ltd. “Grauda spēks” and extruded with a twin screw extruder at Ltd. “Milzu”. The experiments showed that the extrusion process had decreased the protein content by 9%, but the starch content had risen by 13% with the addition of wheat flour. But, for sample, without added wheat flour differences were not significant. No significant size differences were observed in the obtained samples and pH values had no significant differences between extruded samples.
显示更多 [+] 显示较少 [-]Food safety challenges in the tourism processes
2019
Zsarnoczky, M.B., Kodolanyi Janos Univ., Budapest (Hungary) | Zsarnoczky-Dulhazi, F., University of Physical Education, Budapest (Hungary) | Adol, G.F.C., Szent Istvan Univ., Goedoelloe (Hungary) | Barczak, M., University of Economy, Bydgoszcz (Poland) | David, L.D., Constantine the Philosopher Univ. in Nitra (Slovak Republic)
The modern food industry is among the key partners of today’s global tourism. As part of the tourism processes, tourists buy and consume local food in the local catering facilities. Furthermore, tourists are usually willing to try out gastronomy specialties during their travels. Food safety is important for tourists although it is not always part of their conscious behaviour in the destination. Food safety standards are regulated by international contracts based on the analysis of more half a century’s experiences. Within processes related to the changes in the external environment, there are emerging issues – although in different intensity - like chemical and microbiological contamination or food terrorism. Due to the immense number of participants in tourism, it is of key importance to raise awareness of threats like food decay, infections and other negative impacts, because food safety if a basic needs in all tourism destinations. The amount of waste food is increasing dramatically at a global scale. The study will introduce the findings of a food safety research in Hungary, providing useful knowledge to all stakeholders of the tourism industry.
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