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xxx P. Kic, L. Ruzek and E. Popelarova
Concentration of air-borne microorganisms in sport facilities
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Concentration of air-borne microorganisms in sport facilities

P. Kic¹*, L. Ruzek² and E. Popelarova²

¹Czech University of Life Sciences Prague, Faculty of Engineering, Department of Technological Equipment of Buildings, Kamycka 129, CZ165 21 Prague, Czech Republic
²Czech University of Life Sciences Prague, Faculty of Agrobiology, Food and Natural Resources, Department of Microbiology, Nutrition and Dietetics, Kamycka 129, CZ165 21 Prague 6, Czech Republic
*Correspondence: kic@tf.czu.cz

Abstract:

This paper is focused on the microclimatic research in several buildings and rooms used for sport at the University. The attention is paid mainly to the problems of dimensions of space, capacity and activity of sportsmen, and influence of space ventilation. The air samples for microbiological analyses were taken by the microbial air sampler Merck Mas-100 Eco and cultivated by potato-dextrose agar and nutrient agar. Captured microorganisms, are expressed as colony forming units per m3 (CFU m-3). Measurement results showed that bacteria average quantity was statistically significantly less without students (562 CFU m-3) than with students (1,024 CFU m-3). The students inside the rooms increased the bacteria concentration. From this point of view the ventilation is not adequate for the removal of bacteria from ventilated spaces. From the results we can conclude that the great importance on the air quality in terms of a specific bacteria concentration has the specific volume of the room per one athlete. The worst situation is in rooms with the smallest volume, which has the largest biological load of the space. The lowest quantity of bacteria was in the swimming pool all year round (152 to 300 CFU m-3). The opposite situation was in average quantity of filamentous fungi, which was with students and ventilation (57 CFU m-3) and without students but without ventilation (109 CFU m-3). The pollution of air by fungi was higher without ventilation.

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xxx M. Buřič, P. Novák, and J. Hůla
Effect of PTO- driven tillage machines on soil particles transfer
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Effect of PTO- driven tillage machines on soil particles transfer

M. Buřič, P. Novák*, and J. Hůla

Czech University of Life Sciences Prague, Faculty of Engineering, Kamýcká 129, CZ165 21 Prague 6 – Suchdol, Czech Republic
*Correspondence: novakpetr@tf.czu.cz

Abstract:

Displacement of soil particles by erosion can be seen as a major threat to the quality of agricultural land in the conditions of Czech Republic. While the effects of water and wind erosion have long been investigated and reported, the effect of soil tillage technology on soil particles translocation are relatively new area of agriculture research. Soil tillage may contribute to the undesirable translocation of soil particles towards lower-lying parts of fields especially on slopes. The effect of soil tillage implements on soil particle translocation has not been sufficiently explained yet. The object of this research was to assess the influence of PTO (power takeoff)-driven tillage machines on soil particle translocation during secondary tillage (soil preparation). Measurements to determine the displacement of soil particles were performed in location Nesperská Lhota in the Central Bohemia Region. Measurements were performed on a sandy loam cambisol after harvest winter cereals (winter wheat). To indicate displacement of soil particles was used grit of white limestone (size 10–16 mm). Limestone was put down into the trench with known position orthogonal to the direction of working operations. Subsequently were performed working operations in the specified sequence. Limestone particles were counted and weighed in each section. It was detected by measuring the different nature of displacement for each machine. Statistical significance of differences in the weight of translocated particles was evaluated for different type of machines.

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xxx M. Kroulik, J. Hulaand V. Brant
Field trajectories proposals as a tool for increasing work efficiency and sustainable land management
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Field trajectories proposals as a tool for increasing work efficiency and sustainable land management

M. Kroulik¹*, J. Hula¹and V. Brant²

¹Czech University of Life Sciences Prague, Faculty of Engineering, Department of Agricultural Machines, Kamycka 129, CZ16500 Prague, Czech Republic
²Czech University of Life Sciences Prague, Faculty of Agrobiology, Food and Natural Resources, Department of Agroecology and Biometeorology, Kamycka 129, CZ16500 Prague, Czech Republic
*Correspondence: kroulik@tf.czu.cz

Abstract:

Together with the requirement for higher productivity the average performance and the weight of agricultural machines are increasing. Agricultural land is increasingly exposed to pressures caused by agricultural machinery. The heavy agricultural machinery passes across a field are frequently associated with technogenic soil compaction. Soil compaction is one of the main problems of modern agriculture. From the previous measuring of the traffic intensity it was found 86.13% of the total field area was run-over with a machine at least once a year, when using conventional tillage and 63.75% of the total field area was run-over when using direct seeding technology, with dependence on the working width of the machines. Field passes are inevitable in present agriculture. As a result of the increase of total machines weight, it is necessary to optimize the traffic lines trajectories and limit the entries of the machines in the field. At present, the choice of traffic lines direction is based primarily on the experience of drivers or the practice of farmers. There are a number of influences that affect the machine work efficiency. Monitoring of the tractor, on an irregular 8 fields showed the following results. Eight-meter working width tiller or seeder brought shortening of total length of turns at headlands with the change in trajectory azimuth. For purposes of measuring the monitored tractors were equipped with monitoring units ITineris. An overview of the chosen directions of the trajectories and the lengths of working and non-working passes was obtained. Based on the shape of the plot, the trajectory of the lines was also modelled. Suitable traffic lines directions in terms of the ratio of work and non-work passes were searched.
Based on records of real trajectories, the ratio of working and non-working path ranged between 6.3 and 15.2%. It was obvious from the results that the shortening of non-working passes and turns in comparison with the originally chosen trajectory directions was achieved by optimization. This was especially valid for complex shapes of fields. Trajectory optimization leads to a reduction of total length of path in all cases. The reduction in total length of path ranged from 69.7 m to 1,004.8 m. Changing the length of the working path ranged from 10.9 m to 264.9 m with the change in azimuth. The extension was observed in three cases. The highest part on the change of the overall length of the path presented nonworking rides.

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xxx K. Tamm, I. Bender, E. Nugis, L. Edesi and T. Võsa
The impact of the termination technology of agro-ecological service crops on soil properties in open field vegetable production
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The impact of the termination technology of agro-ecological service crops on soil properties in open field vegetable production

K. Tamm*, I. Bender, E. Nugis, L. Edesi and T. Võsa

Estonian Crop Research Institute, J.Aamisepa 1, EE48309 Jõgeva, Jõgeva Vald, Estonia
*Correspondence: kalvi.tamm@etki.ee

Abstract:

The agro-ecological service crops (ASC) are introduced in the agro-ecosystems to provide or enhance ecological services, thus promoting the whole soil-plant system equilibrium. To avoid competition with the subsequent cash crops, the growth of the interposed ASC is terminated in advance of the cash crop planting. The traditional, most widespread technique to terminate the ASC is incorporation as green manure into the soil by tillage (GM). However, since tillage includes energy and labour consuming and soil disturbing operations, the use of no/reduced tillage techniques (as the roller crimping technology-RC) has received increasing interest.
An international research consortium (SOILVEG) including Estonian Crop Research Institute, was established in 2015 with the aim to study among others the impact of ASC termination on soil dry bulk density (BD), water content, soil structure and microbiological activity. Data are collected from Estonian trials in 2016 and 2017 at Jõgeva.
The physical properties of 0–40 cm soil layers were determined. Higher BD in soil layers (0–20 cm) of plots with ASC and RC was determined comparing to the GM and control plots. Bigger water content in same layer of plots with ASC and the RC was determined comparing to the GM plots. The use of the ASC-s helped to arise ratio of agronomically preferred soil particles.
Microbial activity was estimated by assessing of enzyme dehydrogenase activity in 0–20 cm soil layer. There were no statistically relevant differences in soil dehydrogenase activity (DHA) between the RC and GM treatments.

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xxx J. Sepp, K. Reinhold, M. Järvis and P. Tint
Human factors and ergonomics in safety management in healthcare: building new relationships
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Human factors and ergonomics in safety management in healthcare: building new relationships

J. Sepp¹*, K. Reinhold², M. Järvis² and P. Tint²

¹Tallinn Health Care College, Kännu 67, EE13418 Tallinn, Estonia
²Tallinn University of Technology, Ehitajate 5, EE19086 Tallinn, Estonia
*Correspondence: jaana.sepp@ttk.ee

Abstract:

Human factors are playing an essential role in ensuring occupational health and safety at work. In the healthcare sector, relevant factors include optimizing the interaction of humans with their technical, social working environment, and human characteristics such as knowledge and motivation. Those factors affect the ability to provide good quality of healthcare and safety performance. The aim of this paper is to analyse factors related to safety knowledge, communication and professional competence among caregivers in nursing homes. A group of professionals studied (n = 241, includes nurses and caregivers) completed a validated questionnaire. Descriptive statistics and correlation analyses were applied, using SPSS Statistics 24.
Our study revealed that over half of the respondents possess an occupational certificate and the majority of employers organize regular in-service training at workplaces. Respondents who claimed that in-service trainings are not regular still stated that they generally receive safety and ergonomic related trainings, trainings for working with special equipment. However, only a quarter of respondents have access to occupational safety trainings that focus on specific risks at work.
Based on the results of the study, we emphasize the need of integrating human factors in the safety management system in nursing homes with a special focus on adequate safety training in order to develop necessary skills and knowledge of workers. This would enhance employees’ ability to cope successfully with the elderly and people with special needs, to provide safe and high-quality care as well as confidence and the knowledge how successfully they manage conflicts in order to keep good relationships at work.

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xxx A. Kabutey, D. Herak, C. Mizera and P. Hrabe
Mathematical description of loading curves and deformation energy of bulk oil palm kernels
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Mathematical description of loading curves and deformation energy of bulk oil palm kernels

A. Kabutey¹*, D. Herak¹, C. Mizera¹ and P. Hrabe²

¹Czech University of Life Sciences Prague, Faculty of Engineering, Department of Mechanical Engineering, Kamycka 129, CZ16521 Prague, Czech Republic
²Czech University of Life Sciences Prague, Faculty of Engineering, Department of Material Sciences and Manufacturing Technology, Kamycka 129, CZ16521 Prague, Czech Republic
*Correspondence: kabutey@tf.czu.cz

Abstract:

The study aimed at describing the experimental and theoretical relationships between the force and deformation curves as well as the deformation energy of bulk oil palm kernels under compression loading. Vessel diameters of 60, 80 and 100 mm with initial pressing heights of the bulk kernels measured at 40, 60 and 80 mm were examined by applying a maximum compressive force of 200 kN and a speed of 5 mm min-1. For the theoretical description of the force and deformation curves, the tangent curve mathematical model was applied using the MathCAD 14 software where the force coefficient of mechanical behaviour, A (kN), the deformation coefficient of mechanical behaviour, B (mm-1) and the fitting curve function exponent, n (-) were determined respectively. The determined coefficients in addition to the maximum deformation values obtained from the compression test were used for the estimation of the theoretical or analytical deformation energy. The determined regression models expressing the deformation, numerical energy and theoretical energy as well as the tangent model coefficients A and B dependent on the vessel diameter and pressing height were statistically significant (P < 0.05) or (F-ratio > F-critical). Improving the mechanical pressing of oil extraction for both domestic and industrial applications still remain a concern of researchers and engineers.

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xxx I. Szabó, M. Hushki, Z. Bártfai A. Lágymányosi and L. Kátai
Modelling of operator’s focusing scheme along working hours: Windrowing and cultivating operations
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Modelling of operator’s focusing scheme along working hours: Windrowing and cultivating operations

I. Szabó, M. Hushki, Z. Bártfai A. Lágymányosi and L. Kátai*

Szent István University, Faculty of Mechanical Engineering, Institute of Mechanics and Machinery, Páter K. street 1, HU2100 Gödöllő, Hungary
*Correspondence: katai.laszlo@gek.szie.hu

Abstract:

Enhancing productivity and cost reduction are two main targets for any production operation. In the agricultural field; It is the role of researchers to come out with reliable models and make it available to be used in modern farming management organizations as well as to the rural farmers. When it comes to the Human Machine Interface it is essential to assess the system in term of the Human Cantered Design aspects. This research is focusing on the developing simple models for the operator’s focusing scheme as a human behaviour inside an off-road vehicle cabin based on the operator’s focusing scheme measuring along working hours using proven and up to date technologies. The results of this research provide the decision makers with reliable inputs using proven methodology regarding the change of operator’s focusing scheme along working hours in two agricultural operations ‘windrowing and cultivating’. Both operations are requiring continuous physical involvement of the operator for checking the attached tool and steering of the vehicle in the planned track, which is directly related to the accumulated passive fatigue as a main contributor of resulted data.

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xxx D. Kļava, S. Kampuse, L. Tomsone, T. Kince and L. Ozola
Effect of drying technologies on bioactive compounds maintenance in pumpkin by-products
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Effect of drying technologies on bioactive compounds maintenance in pumpkin by-products

D. Kļava, S. Kampuse*, L. Tomsone, T. Kince and L. Ozola

Latvia University of Life Sciences and Technologies, Faculty of Food Technology, Riga street 22, LV-3004 Jelgava, Latvia
*Correspondence: skampuse@inbox.lv

Abstract:

During the pumpkin processing large amounts of waste material as a combination of pumpkin peel, seeds and the flesh between seeds has produced. Therefore it is important to investigate the possibilities for using the pumpkin residues. The aim of this research was to investigate the effect of different drying technologies on maintenance of bioactive compounds in pumpkin by-products. Two pumpkin residue products of Hubard group pumpkins were used to obtain pumpkin powder: residue products formed in the process of extracting industrial pumpkin purée by heating it in a heat exchanger and treating through a sieve of pulpier; residues resulting from pumpkin juice extraction process mechanically pressed from fresh, chopped pumpkins. In order to be able to choose the most suitable drying technology pumpkin by-products were dried in the microwave-vacuum, convective (at 40, 50, 70 and 80 °C) and freeze-drying type dryers. For all samples total carotenes, the ascorbic acid, total phenols content (TPC) and antiradical activity (DPPH˙, ABTS˙+) were determined by using standard methods. The highest total carotenes content was retained in freeze-dried pumpkin powders. The most suitable drying method for obtaining pumpkin powder with the highest ascorbic acid, total phenolic content and antiradical activity is drying in convective type drying at 80 °C temperature.

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xxx E. Merisalu, D. Mugur and P. Kic
Importance of microclimate conditions and CO2 control in educational buildings: a case study
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Importance of microclimate conditions and CO2 control in educational buildings: a case study

E. Merisalu¹*, D. Mugur¹ and P. Kic²

¹Estonian University of Life Sciences Tartu, Institute of Technology, Fr. R. Kreutzwaldi 56/1, EE51006 Tartu, Estonia
²Czech University of Life Sciences Prague, Faculty of Engineering, Department of Technological Equipment of Buildings, Kamýcká 129, CZ165 21 Prague, Czech Republic
*Correspondence: eda.merisalu@emu.ee

Abstract:

Current efforts to minimize energy losses and maximize energy savings for heating of all houses are most often gained by insulating facades and replacing windows. However, these measures can have a significant negative impact on human health and these problems can occur in buildings with a high concentration of people, such as school buildings. The aim of this paper is to analyse the results of measurements of air temperature, relative air humidity and carbon dioxide in winter period in the classrooms of two universities, Estonian University of Life Sciences (EULS) in Tartu and Czech University of Life Sciences (CULS) in Prague. The measurements have carried out in 2017-2018 in eight classrooms of the EULS and two classrooms of the CULS. The external and internal temperature, relative humidity and concentration of carbon dioxide have measured in the classrooms during a few days in the winter period. In the lecture rooms of CULS, when the air conditioning was off, the levels of CO2 exceeded the recommended levels about two times. The average internal temperature and CO2 concentrations in the classrooms of EULS follows the norms and refers on good ventilation. The extremely low relative humidity in the classrooms of EULS at 17.1 ± 2.6% refers to a high risk of allostatic load and respiratory symptoms among students. It is important to pay attention on regular ventilation and relative air humidity control in the teaching rooms, especially with high number of students to prevent seasonal sickness of upper respiratory tract.

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xxx D.V. Cao and P. Kic
Analysis of indoor temperature in the workshop building during the summer: a pilot study
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Analysis of indoor temperature in the workshop building during the summer: a pilot study

D.V. Cao* and P. Kic

Czech University of Life Sciences Prague, Faculty of Engineering, Department of
Technological Equipment of Buildings, Kamýcká 129, CZ165 21, Czech Republic
*Correspondence: caodoan2006@gmail.com

Abstract:

The aim of this paper is the presentation of measurements’ results and the calculation
method for analysis and evaluation of climate conditions as well for using of natural illuminance
in two large simple buildings during summer which could be used to calculate power demand for
the air cooling to reduce the indoor temperature caused by solar radiation. In this research, we
carried out experiments of measuring the indoor temperature at level of working place which is
1.1 m, in two similar large workshops with floor area 260 m2 and height 6.5 m, during several
hot summer days. The indoor conditions were strongly influenced by the solar radiation as the
buildings have large wall and roof windows. The indoor air temperatures in the first building
achieved 39.5 °C, which caused the heat stress for workers. The indoor air temperatures in the
second building achieved only 29.5 °C. The calculated power demand for the air cooling to reduce
the indoor temperature to 25 °C is 25.6 kW in the first building, the cooling power for second
building is 14.9 kW. We investigated measured construction of the workshop and we set up the
formula in order to calculate thermal balance. The measurement results and calculated results in
two buildings are compared and summarized in the tables and in the graphs for analysis. As a
general conclusion, it must be said that solar radiation has a big influence on the air temperature
and methods of passive air-conditioning should be more applied also on the production buildings
in industry, agriculture and other branches of civil engineering to release heat increasing air
temperature inside the building.

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xxx M. Polák
Application of conversion model for designing hydrodynamic pumps in turbine mode
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Application of conversion model for designing hydrodynamic pumps in turbine mode

M. Polák

Czech University of Life Sciences in Prague, Faculty of Engineering, Kamýcká 129, CZ16521, Praha 6, Czech Republic
Correspondence: karel@tf.czu.cz

Abstract:

The use of the smallest water resources has been coming again to the centre of interest in recent years. A water engine – turbine, is the heart of these power plants. This is usually the highest expense for the investor, in terms of cost. The effort is therefore to seek investment less demanding alternatives. One of them is the use of hydrodynamic pumps in reverse turbine operation. This paper provides a methodology for conversion of parameters of the smallest power pumps (micro hydro sites) to turbine operation. The conversion model is based on the results of experimental research at the author’s workplace and is suitable for pumps with low specific speeds and outputs. The pump design process for turbine mode is complemented by a practical example for a specific deployment site. This example also serves to verify the accuracy of the conversion model.

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xxx A. Trūpa, B. Ošmane and I.H. Konošonoka
Fodder beans and peas in the diet of dairy cows
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Fodder beans and peas in the diet of dairy cows

A. Trūpa¹*, B. Ošmane² and I.H. Konošonoka²

¹Latvia University of Life Sciences and Technologies, Liela iela 2, LV-3001 Jelgava, Latvia
²Institute of Agricultural Resources and Economics, Priekuli Research Centre, Zinatnes iela 2, LV-4130 Priekuli, Priekulu parish, Priekulu district, Latvia
*Correspondence: aiga.trupa@llu.lv

Abstract:

The Holstein-Friesian Black-and-White cows were grouped into four treatments groups according to the analogue principle (n = 4 × 5). Lactating dairy cows were included in the trial in the initial lactation phase with the average milk yield of 23.00 kg per day, fat content 4.10% and 3.20% protein content in milk. The analyses of the chemical composition of legume grains show, that crude protein and undegraded intake protein (UIP) were higher in fodder beans than in peas, respectively 29.97% and 25.04% of dry matter but UIP content, respectively 40.51% and 39.69% of crude protein. There was a total of 17 amino acids detected in legume grains and soybean meal. The highest concentration of arginine, leucine, glutamic acid, aspartic acid and isoleucine was in fodder beans, respectively 0.76%, 0.58%, 0.67%, 0.42% and 0.29% more than in peas. Even though the daily milk yields decreased for all the cow groups during the experiment, which was normal during the lactation period, yet the milk yield decreases for the trial groups. The highest total amount of amino acids in milk was detected in 3rd and 2nd trial cow groups, respectively, 4.00 g kg-1 and 3.90 g kg-1 which was fed fodder beans and peas. The milk sale and feed cost summary records for the trial that lasted 90 days show that economic efficiency of peas plus beans has been positive.

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xxx R. Põldaru, A.-H. Viira and J. Roots
Optimization of arable land use to guarantee food security in Estonia
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Optimization of arable land use to guarantee food security in Estonia

R. Põldaru*, A.-H. Viira and J. Roots

Estonian University of Life Sciences, Institute of Economics and Social Sciences, Department of Business Informatics and Econometrics, Fr. R. Kreutzwaldi 1, EE51006 Tartu, Estonia
*Correspondence: Reet.Poldaru@emu.ee

Abstract:

Agricultural and food sector has an important role to play in ensuring food security. A competitive agricultural sector warrants food security through increasing level of self-sufficiency in food, and export of surplus production in the sub-branches where it has a comparative advantage. One of the strategic tasks of the state is to secure food supply for the population. To perform this task, the state should estimate if the agricultural producers have the necessary capacity and resources to produce food to meet the needs of population. Mathematical modelling can be used as a tool in solving this analytical problem. The paper demonstrates possibilities of implementing linear programming model in optimizing the use of arable land for ensuring the food demand of Estonian population. The Estonian arable land use optimization model is essentially a static balancing model that simulates the demand and supply of basic food products (meat, dairy products, cereal products and potatoes). The basis for the demand side in the model is Estonian population, divided into 10 groups according to gender and age. The energy and protein needs of the respective population groups are taken into account. The supply side of the model is a typical agricultural production model that guarantees the consistency of crop and livestock farming. The model consists of 163 variables and 178 constraints (equations). The objective of the model is to minimize the use of arable land for field crops to ensure fodder for animal feed, and food for human food consumption. The model is used to analyse various land use strategies. According to the modelling results for ensuring food security of Estonia and to maintain export of dairy products, for which Estonia has a comparative advantage, in the 2016 volume, the total optimal arable land equals to 490,688 ha. There should be 83,600 dairy cows (with average milk yield 9,000 kg cow-1). It is necessary to grow 755,700 piglets per year in order to secure 40 kg of pork per inhabitant. Land use optimization results indicate that Estonian agriculture is able to supply Estonian people with the minimum necessary main food products to guarantee food security, and allows to export essential products (cheese, butter, skimmed milk powder, whole milk powder).

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