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The use of pesticides dominates agriculture today, but unfortunately poses several threats to the environment and humans, through bioaccumulation and biomagnification. This research tested the efficacies of Salvia officinalis subsp. lavandulifolia and Salvia officinalis subsp. major aqueous extracts against Botrytis cinerea in order to curb chemical control and subsequent reduction in their threats. The leaves of Salvia officinalis subsp. lavandulifolia and Salvia officinalis subsp. major were collected in July and September 2019 and shed-dried. Then 90 ml hot distilled water was added to10 g of the crumbled leaves from each sample, left for 24 hours and the filtrate was used to prepare two different media concentrations: CC1 containing 99 ml PDA (i.e. Potato Dextrose Agar) and 11 ml extract (or ion-exchange water as control 1); and CC2 containing 88 ml PDA and 22 ml extract (or ion-exchange water as control 2). The 10 ml from each mixture (CC1, CC2 and the controls) was used as the growth media in 5 replications. Each Petri dish was centrally inoculated with 9 mm2 B. cinerea mycelia, and the area of colony was taken. All the extracts effectively inhibited the growth of Botrytis cinerea, with Som2 showing the highest inhibition. In Salvia officinalis subsp. lavandulifolia, Sol1 (July harvested) showed higher inhibition (53.90%) compared to September harvested Sol2 (40.78%) in CC2 at 3 days post inoculation (PI), while in Salvia officinalis subsp. major, Som2 (September harvested) showed higher inhibition (15.01%) compared to July harvested Som1 (0.04%) in CC1 at 7 days PI. Generally, CC2 showed higher inhibition compared to CC1.

One of the main goals of the ship design process is the reduction of the total resistance, which is nowadays even more highlighted due to increasingly stringent rules related to ship energy efficiency. In this paper, the investigation of the impact of the bow on the total resistance of a yacht is carried out for three models by towing tank tests and numerical simulations. The verification and validation studies are performed, and satisfactory agreement is achieved. Also, a comparison of three turbulence models for the prediction of the total resistance of a yacht is made. The flow around the models of the yacht is analysed and it is demonstrated that bulbous bow causes the reduction of wave elevations. Experimental and numerical results indicate that the decrease in the total resistance due to bulbous bow can be up to 7%. Finally, the applicability of CFD within the ship design process is presented.

The effects of a single strain lactic acid producing bacteria (LAB) (Lactobacillus farciminis 5x109 CFU/kg) and a single strain butyric acid producing bacteria (BAB) (Clostridium butyricum 2.5x109 CFU/kg) with or without wheat bran supplementation (WB), were investigated on the production traits and on several gut characteristics of broiler chickens. In total, 576 male Ross 308 day-old chickens were divided into 24 floor pens and fed a corn-soybean based control diet (C) and five other probiotic or wheat bran supplemented diets (LAB, BAB, LAB+WB, BAB+WB, C+WB) in 4 replicates. The wheat bran content of the starter, grower and finisher diets were 3, 6 and 6%, respectively. During the 37 day long fattening period, growth rate, feed intake were recorded and feed conversion was calculated. At the end of the trial, 8 chickens per treatment were slaughtered and the following parameters investigated: trypsin, lipase and amylase activity of the jejunal chyme, ileal histomorphology and Lactobacillus load. None of the treatments resulted significant differences in the production traits (P>0.1). BAB supplementation tended to decrease digestive enzyme activity. Feeding WB in all combination increased crypt depth (P=0.002), ileal muscle layer thickness (P=0.001) and decreased the villi: crypt ratio (P=0.037) in the ileum.

Authors analysed the reproductive, growth and slaughter records of Pannon White rabbits based on records collected between 1992 and 2014. The examined traits were: average daily gain (ADG), thigh muscle volume (TMV) and litter weight at day 21 (LW21). Genetic parameters were estimated using basic and extended (with dominance effects) single trait animal models using the REML procedure. Heritability estimates ranged between low and moderate for all traits (ADG: 0.25-0.3±0.01, TMV: 0.21-0.24±0.02-0.03, LW21: 0.07-0.19±0.01). Random litter effects were moderate for ADG (0.24-0.25±0.01) but were low for TMV (0.09-0.1±0.01-0.03). Magnitude of permanent environmental effects exceeded that of the heritability values for LW21 in most models. Applying the extended complete models dominance effects were low for ADG and TMV (0.03±0.01-0.02) and moderate for LW21 (0.23±0.01). Among the estimated genetic correlation coefficients, the observed negative value between ADG and TMV (-0.31±0.03) and between TMV and LW21 (-0.38±0.13) were unfavourable. Based on the different models the estimated breeding values showed high stability as their rank correlation coefficients were close to unity (0.93-0.99).

The assessment of hydrodynamic characteristics of a screw propeller in open water test is of crucial significance in the preliminary design stage of a ship. The open water characteristics can be accurately predicted by towing tank measurements. Taking into account the significant advances in computational fluid dynamics which has enabled the numerical assessment of the open water characteristics, the time and the cost of propeller design are significantly reduced. Open water characteristics can be assessed numerically using potential and viscous flow theory. The former one allows faster and simpler preliminary determination of open water characteristics. Within this paper, numerical simulations are performed for Gawn series propellers utilizing open source code OpenProp based on the moderately loaded lifting line theory and commercial software package STAR-CCM+ based on viscous flow theory. The latter one is more time consuming regarding the time required for the preparation of simulation as well as computational time. The obtained numerical results are compared with regression polynomials based on the experimental data. The validation of the results has pointed out that OpenProp can be used as practical and efficient tool in preliminary design of screw propellers.

Common ragweed (Ambrosia artemisiifolia) is an invasive alien species indigenous to North America. Ragweed is a big threat to agriculture and has a serious impact on human health. The most important area with ragweed occurrence within Europe is Pannonian Plain in Central Europe. This research introduces for the first time the unique, direct broad-scale survey of A. artemisiifolia in relation to real-life occurrence and infestation in the field. To understand the distribution of ragweed in the territory the geospatial analysis was applied to create 2D map in ArcGIS environment. The field survey was undertaken during summer 2014 in the Žitný ostrov (Slovakia). The investigation revealed that spatial occurrence of A. artemisiifolia is not homogeneous and there is also striking territorial heterogeneity of infestation rate. Ragweed was observed at 80 (47.2%) out of 169 sites. The infestation of arable land (mostly stubbles) varied from weak infestation, 24 sites (1-30 plants*10 m-2) to heavy infestation, 26 sites (˃80 plants*10 m-2). The research on associated plant communities was also carried out. Stubble field’s vegetation was found to be highly species poor, on an average only 2.5 species*10 m-2. Among 40 recorded species the most frequent (noticed at 25% sites) were Datura stramonium, Chenopodium album, and Mercurialis annua. This broad-scale survey provides an overview and useful information on considerations needed to make decisions about ragweed control and potential future expansion. The presented study offers also inventory of ragweed frequency over the large area.

In this paper, numerical simulation of the viscous flow around a tanker model was carried out utilizing software package STAR-CCM+. A mathematical model based on Reynolds Averaged Navier-Stokes equations, k-ε turbulence model and Volume of Fluid method for describing the motion of two-phase media are given. Necessary boundary conditions for the mathematical model and the method of discretization are described as well. The influence of the grid density on the numerical results for the total resistance of tanker model was investigated using three different grid densities. Two different types of k-ε turbulence model are implemented and the deviations in numerical results are highlighted. Results for total resistance of tanker model, obtained by numerical simulations, were validated against experimental results. Experiments were performed in the towing tank of Brodarski Institut in Zagreb for wide range of Froude numbers. It has been shown that for all three grid densities and both types of k-ε turbulence model satisfactory agreement with experimental results can be achieved for whole range of Froude numbers. The scale effects are investigated by Computational Fluid Dynamics study for the same tanker model in three different scales. Numerically calculated scale effects on the wave resistance are reviewed.

Impact of pesticides and plant nutrition on wheat crop, as well as their interaction was studied in a small plot field trial run at the experimental site on eutric cambisol type soil, in 2006 and 2007. The results obtained suggest, that treatments applied – both the increasing rate of fertilizers (N0P0K0, N40P100K100, N80P100K100, N120P100K100, N160P100K100) and the increasing intensity of pesticide application (Ø, herbicide, herbicide+ fungicide, herbicide+ fungicide+ insecticide) – had significant effect on the grain yield of wheat. In case of fertilizer application each N rate resulted in a further significant yield increase in the average of pesticide applications. In 2006 the minimum yield was 2.2 t ha-1, the maximum 5.5t ha-1, and the average 4.3 t ha-1. In 2007 the minimum yield was 1.00 t ha-1 and the maximum 4.6 t ha-1 the average 3.2 t ha-1. In accordance with the increment of the level of plant nutrition and plant protection applications a decreasing magnitude of yield increase was observed. Plant nutrition applications had a more definite effect on yield figures in comparison with that of plant protection treatments. Meteorological conditions of the crop years studied were considerably buffered by agronomic applications applied.

Pedigree and field test data - collected between 1997-2005 - were analyzed in a group of 68062 Hungarian Landrace pigs. The analysed traits were loin depth (LD), fat depth1 (FD1) and fat depth2 (FD2). In the present study inbreeding coefficients, pedigree completeness (complete generation equivalents) and inbreeding depression for LD, FD1 and FD2 were estimated. Increasing number of generations that were considered in the pedigree the estimated inbreeding coefficients did not change after the 5th generation, but pedigree completeness was continuously increasing. The estimated inbreeding depression for LD, FD1 and FD2 were different applying 5 different models but the magnitude of the differences was small. Increasing inbreeding coefficient by 10% caused LD decrease by 0.084 mm, the FD1 by 0.062 mm and did not affect FD2. It can be concluded that the estimated inbreeding depression was low and substantial depression can not be expected in the near future. However, the low level of inbreeding of the studied population can partly be explained by the short pedigrees. This suggests that Hungarian pig breeders may often import breeding animals or carry out herd replacements rather than apply within group selection.

Genetic analysis was conducted on Hungarian pig seed stocks. The breeds, which were used in the investigation, were Hungarian Large White, Hungarian Landrace, Duroc, and Pietrain respectively. Regarding the field test (own performance test) 40391; 54523; 4318; 3501; different animals were recorded in the above mentioned breeds. Meanwhile in the station test 3911; 2457; 695; 568 records were used concerning the same breeds. Genetic parameters were estimated using the software VCE 4 developed by Groeneveld (1998). Variance components were obtained by running a joint model (field and station test). During the analysis special attention was given to the received genetic correlation coefficients in order to compare the results of the field and station tests respectively. Genetic correlation coefficients of 0.52; 0.36; 0,43; 0.80 were found between the age at the time of the test (field test) and days of fattening (station test) having the same order of the breeds as previously. The moderately high genetic correlation coefficients between these previously mentioned traits (representing the growing intensity) justify that these methods are based upon each other and make the efficient selection possible. Among the traits representing meat quality genetic correlation coefficients of –0.13; -0.41; -0.63; +0.13 were found between the average backfat depth (field test) and valuable cuts (station test) respectively. The high variability of the coefficients suggests the need for further investigation of this area and also the importance of precise measurement of the average backfat depth since a possible imprecise measurement of this trait might be the reason for the received variability.