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This study aims to analyse the effect of selected variation factors on the ejaculate characteristics of boars and to characterise changes in ejaculate characteristics in Landrace, Large White, Duroc, and Pietrain boars during their use for artificial insemination. The original value of this work lies in the estimation of the percentage share of individual components of variability in shaping the traits of boar ejaculate. A total of 943 ejaculates collected from 77 boars used for artificial insemination were analysed. This study began when the boars were at 8–9 months old. Ejaculates were collected in nine consecutive months from the start of the boars’ use. Immediately after collection, they were analysed for ejaculate volume, sperm concentration, percentage of sperm with progressive motility, total number of spermatozoa, and number of insemination doses per ejaculate. The results were analysed according to three criteria: breed of boar (Landrace, Large White, Duroc, and Pietrain), age of boar (up to 10 months, 11–13 months, 14–17 months, and more than 17 months), and season (spring, summer, autumn, and winter). The analysis of the variation in ejaculate characteristics took into account the share of each factor (boar breed, boar age, and season) in the variation, as well as the interactions between factors. The effects of the three factors and interactions between them were calculated using an ANOVA (analysis of variance). The variation was shown to depend mainly on the breed and age. These two factors and the interaction between them determine about 80% of the variation in ejaculate characteristics. The season also has an effect, but its share in the influence of variation on ejaculate characteristics is relatively small. Ejaculates from Landrace boars are the most favourable for insemination, with a large volume, a relatively high sperm concentration, and the highest number of sperm. The highest number of insemination doses can be prepared from Landrace ejaculates—on average, 2.7–6.7 more doses than from the other breeds. Duroc boar ejaculates are most distinctive, with a very low volume but a very high sperm concentration and the highest sperm motility. The ejaculates of Pietrain boars showed the opposite pattern, with the largest volume but the lowest sperm concentration. The sexual development of young boars, expressed as an increase in ejaculation performance, progresses during their first year of insemination use.

Shallow landslides damage buildings and other infrastructure, disrupt agriculture practices, and can cause social upheaval and loss of life. As a result, many scientists study the phenomenon, and some of them have focused on producing landslide susceptibility maps that can be used by land-use managers to reduce injury and damage. This paper contributes to this effort by comparing the power and effectiveness of five machine learning, benchmark algorithms—Logistic Model Tree, Logistic Regression, Naïve Bayes Tree, Artificial Neural Network, and Support Vector Machine—in creating a reliable shallow landslide susceptibility map for Bijar City in Kurdistan province, Iran. Twenty conditioning factors were applied to 111 shallow landslides and tested using the One-R attribute evaluation (ORAE) technique for modeling and validation processes. The performance of the models was assessed by statistical-based indexes including sensitivity, specificity, accuracy, mean absolute error (MAE), root mean square error (RMSE), and area under the receiver operatic characteristic curve (AUC). Results indicate that all the five machine learning models performed well for shallow landslide susceptibility assessment, but the Logistic Model Tree model (AUC = 0.932) had the highest goodness-of-fit and prediction accuracy, followed by the Logistic Regression (AUC = 0.932), Naïve Bayes Tree (AUC = 0.864), ANN (AUC = 0.860), and Support Vector Machine (AUC = 0.834) models. Therefore, we recommend the use of the Logistic Model Tree model in shallow landslide mapping programs in semi-arid regions to help decision makers, planners, land-use managers, and government agencies mitigate the hazard and risk.

An attempt was made to adapt the physical and chemical characteristics of rapeseed oil (Ro), including its density, viscosity and surface tension to diesel oil in the aspect of its use as a biofuel in diesel engines by adding 10 and/or 15 percent n-hexane to the oil and contacting the obtained mixture with ethanol. After establishing an equilibrium of ethanol extraction in the phase containing a mixture of Ro and n-hexane and the mixture components in ethanol, measurements of the viscosity, surface tension and density of oil phases were performed. The obtained values of these physicochemical parameters for the Ro and n-hexane mixture phase were close to those of diesel oil. Next, engine tests were carried out on the Ro+n-hexane mixture after its contact with ethanol under real driving conditions. The tests showed that the mixture of rapeseed oil with 10% n-hexane in contact with ethanol achieved the highest torque and power values among all Ro-based fuels, and that the decrease in these parameters compared to diesel fuel was the smallest. Moreover, compared to Ro and the mixture of Ro with 10% n-hexane, a higher energy efficiency was obtained, which is due to the favorable physicochemical properties of the fuel—the reduced viscosity and improved volatility.

Introduction: The effect of two smear staining methods on the dimensions and shape of sperm cells in the semen of domestic pigs was evaluated. Material and Methods: The studies were carried out on 30 ejaculates collected from 15 boars, which included five Duroc boars, five Pietrain boars, and five hybrid Duroc × Pietrain boars. Each ejaculate was next sampled to make two microscopic slides, of which one was stained with eosin-nigrosin and the other with eosin-gentian dye. In total, 600 measurements of sperm cells were made. Each sperm was measured for the following morphometric parameters: head length, head width, head area, head perimeter, tail length, and the total sperm length. Results: Sperms measured on slides stained with eosin-nigrosin showed lower dimensions as compared with those stained with the eosin-gentian dye method. Sperm stained with eosin-nigrosin had shorter and narrower heads than sperm stained with eosin-gentian dye. The method of staining, therefore, affected not only the dimensions of the sperm, but also the proportions of the dimensions defining the shape of the sperm. Conclusions: The size and shape parameters in porcine sperm may take on different values depending on the method of semen staining. Sperm cells stained with eosin-nigrosin are smaller than the sperm stained with eosin-gentian dye. The sensitivity of the sperm to the type of dye used for the fixation may be associated with genetic factors.

Groundwater is an important natural resource in arid and semi-arid environments, where discharge from karst springs is utilized as the principal water supply for human use. The occurrence of karst springs over large areas is often poorly documented, and interpolation strategies are often utilized to map the distribution and discharge potential of springs. This study develops a novel method to delineate karst spring zones on the basis of various hydrogeological factors. A case study of the Bojnourd Region, Iran, where spring discharge measurements are available for 359 sites, is used to demonstrate application of the new approach. Spatial mapping is achieved using ensemble modelling, which is based on certainty factors (CF) and logistic regression (LR). Maps of the CF and LR components of groundwater potential were generated individually, and then, combined to prepare an ensemble map of the study area. The accuracy (A) of the ensemble map was then assessed using area under the receiver operating characteristic curve. Results of this analysis show that LR (A = 78%) outperformed CF (A = 67%) in terms of the comparison between model predictions and known occurrences of karst springs (i.e., calibration data). However, combining the CF and LR results through ensemble modelling produced superior accuracy (A = 85%) in terms of spring potential mapping. By combining CF and LR statistical models through ensemble modelling, weaknesses in CF and LR methods are offset, and therefore, we recommend this ensemble approach for similar karst mapping projects. The methodology developed here offers an efficient method for assessing spring discharge and karst spring potentials over regional scales.

Parameters of sexual activity were determined in 49 young boars used for artificial insemination, four times at three-month intervals. The parameters included the time from entering the arena until mounting the phantom; the time from mounting the phantom until achieving erection; the time from achieving full erection until the start of ejaculation; duration of ejaculation; and the number of times the boar mounted the phantom. Characteristics of the ejaculates were also assessed. The libido parameter associated with the greatest efficacy of artificial insemination was the effectiveness of artificial insemination service, the time from entering the arena until the start of ejaculation. The significance of this trait for predicting ejaculation performance was analysed. The libido characteristics were classified into three categories: boars with a short reaction time to the phantom, boars with an intermediate reaction time, and boars with a long reaction time. For these groups, the characteristics of ejaculates collected at the start of the period during which ejaculates were collected and after three, six and nine months were determined. The sexual experience of boars was not associated with the expression of sexual behaviour because young boars during their first three months of ejaculate collections required less time to initiate ejaculation. The ejaculates with the greatest utility were obtained after six months of service. These ejaculates had the largest volume (255.22 mL), and the most insemination doses could be prepared from these ejaculates. On average, more than 23 insemination doses were prepared from ejaculates collected after six months of semen collections, which is about four doses more than from ejaculates collected at the start of artificial insemination service (p < 0.01).The time from entering the arena to beginning ejaculation can be used to predict a boar’s future libido. A relationship was shown between the level of libido and ejaculate characteristics. The ejaculates of the boars which needed the longest time to begin ejaculation at the start of semen collections had the greatest sperm concentration and number. In group 3, the boars’ejaculates contained about 6–9 × 109 more sperm than the ejaculates of boars from group 1. After six months of the experimental period, the difference was nearly 15 × 109 sperm (p < 0.05), and after nine months, it exceeded 22 × 109 sperm (p < 0.01).

This study examined how adding ethanol to diesel fuel affects combustion characteristics, cylinder pressure and NOx emissions in an AVL engine. The research focused on key engine parameters, including autoignition delay, in-cylinder pressure rise rates, the peaks of the mean in-cylinder temperature and NOx emissions. Three fuel types were tested: pure diesel (DF) and blends with 10 and 20% ethanol by volume (DF10 and DF20). The results obtained indicate that increasing the ethanol content in diesel fuel significantly affects the combustion process of the fuel mixture, particularly in its early stage, reducing the benefits of the pilot fuel injection. Moreover, it was observed that the combustion of the DF20 mixture leads to a substantially higher pressure increase in the cylinder, exceeding the values recorded for pure diesel fuel by approximately 25%. Furthermore, the study revealed that ethanol addition increases the peaks of the mean in-cylinder temperature, with a recorded difference of up to 60 °C between pure diesel fuel and DF20. Since NOx formation is highly temperature-dependent, this temperature rise is likely to result in higher NOx concentration. Additionally, a slight effect of ethanol on increasing the ignition delay angle was observed. This remained minor, and did not exceed approximately 1 CA. These findings highlight the complex relationship between ethanol content in diesel fuel, combustion dynamics, and emissions. They emphasize the need for optimizing the injection process for ethanol–diesel blends to balance the benefits of ethanol addition with potential challenges related to combustion efficiency, engine load and NOx concentration.

This paper presents a compact nonlinear thermal model of pulse transformers. The proposed model takes into account differentiation in values of the temperatures of a ferromagnetic core and each winding. The model is formulated in the form of an electric network realising electrothermal analogy. It consists of current sources representing power dissipated in the core and in each of the windings, capacitors representing thermal capacitances and controlled current sources modelling the influence of dissipated power on the thermal resistances in the proposed model. Both self-heating phenomena in each component of the transformer and mutual thermal couplings between each pair of these components are taken into account. A description of the elaborated model is presented, and the process to estimate the model parameters is proposed. The proposed model was verified experimentally for different transformers. Good agreement between the calculated and measured waveforms of each component temperature of the tested pulse transformers was obtained. Differences between the results of measurements and calculations did not exceed 9% for transformers with a toroidal core and 13% for planar transformers.

The aim of this study was to evaluate the dependence between ejaculate traits, sperm morphology, and ejaculate volume in Duroc boars. The analysis involved 121 ejaculates collected from 12 Duroc boars kept in three artificial insemination centres located in central Poland. Ejaculates were collected manually at one-month intervals, over a period of 10 months. At least 10 ejaculates were collected from each boar. The material was divided by ejaculate volume and each ejaculate was assigned to one of three volume groups: 160 mL and lower, 161–200 mL, and 201 mL and higher. The ejaculates were assessed to identify the basic physical traits and determine the incidence of morphological abnormalities in the spermatozoa, specifying major and minor abnormalities. Furthermore, the morphological structure indices for the spermatozoa were also calculated. In large-volume ejaculates, spermatozoa were more elongated in shape, their heads were more elongated and had the largest flagella. With an increase in the ejaculate volume, sperm concentration in the ejaculate decreased. Moreover, while the total number of sperm in the ejaculate increased, the number of insemination doses obtained from a single ejaculate were higher. The volume of ejaculate has little impact on the occurrence of morphological abnormalities and the size of sperm cells. Ejaculate volume is important for the shape of the sperm cells.

This paper presents an analysis of the exhaust gas concentration of a compression ignition engine powered by diesel fuel and rapeseed oil under dynamic conditions. The measurement cycle consisted of a 100 s segment of the WLTC cycle. An attempt was then made to estimate the exhaust gas concentration using predictive algorithms based on parameters recorded using the OBD-II diagnostic interface. The model was validated based on previously unobserved measurements of the measurement cycle, and the procedure was repeated several times with random parameter changes. Due to the dynamic nature of the combustion process (taking into account its non-linearity and inertia), a delayed feature design was used. A consistent time horizon of input information was selected for the tabular and sequential models used. The results obtained indicated that Gradient-Boosted Regression Trees class algorithms achieved the highest quality of fit and were characterised by the greatest stability.