bluuebunny/crossref_metadata_2025 huggingface dataset:
Power and Efficiency Characteristics of a Hybrid Electrochemical-ICE Cycle
Authors: Diskin David , Tartakovsky Leonid
Published: April 2021

Power and efficiency characteristics of a hybrid cycle combining an electrochemical device (Fuel-Cell) and an internal combustion engine (ICE) were analyzed using the low-dissipation model. The low-dissipation model links energy dissipation with the energy transfer rate through the cycle. In the considered cycle, the electrochemical device transforms chemical potential of the fuel to electrical work, and the ICE uses the heat rejected by the electrochemical device and its exhaust effluent for mechanical work production. The cycle efficiency was calculated as a function of the hybridization level. The latter is defined as the electrical work fraction in the total cycle work. The results of the study show that the cycle efficiency is growing with the electrical work fraction increase. On the other hand, maximum power of the cycle is attained at an intermediate hybridization level. Moreover, power to weight ratio and power density of the cycle have maxima at different hybridization level. Cycle cooling losses are modeled as heat leak to the ambient that depends on the temperature and the duration of the cycle. Cooling losses are found to be the most influential parameter in optimization of the hybridization level for maximum power. In the extreme case of zero cooling losses, maximum power could be attained with ICE operation alone without the electrochemical reaction. The latter finding might be of interest for aerial propulsion systems. However, if efficiency is more important - for example for ground propulsion systems - the hybrid cycle is beneficial.
A Digital Twin Based Approach for Simulation and Emulation of an Automotive Paint Workshop
Authors: Escriche lng Sergio , Royo Lucía , Ruperez lng Adrián , Cucalón lng Guillermo , Martinez Aitor , Bacaicoa Luis , Rodriguez Francisco , Lopez Blanca
Published: April 2021

The automotive sector has been adapting in recent years to become a reference in the cutting-edge technological revolution. Concepts like cyber-physical systems, simulation and digital twins have been applied in several aspects of automotive field, from factories to vehicles. A further step towards promoting the digitalization and the impulse of Industry 4.0 within this sector consists in being able to develop a connection between the virtual and the physical world, developing both simulation and Virtual Commissioning (VC).

Considering the relevance of applying these concepts to existing manufacturing plants, this paper deals with the simulation and emulation of an Automotive Volkswagen (VW) Paint Workshop located in Navarra (Spain). The main objective of this paper is to replicate and emulate the behavior of several lines of the workshop based on a Digital Twin (DT) approach, considering mainly production features (number of cars and cycle time). The methodology combines numerical simulation with experimental validation based on both automotive performance guidelines and Workshop schedule. Several ad-hoc models have been developed within Plant Simulation software within Siemens portfolio to simulate the elements of the Workshop. The novelty of the article lies in the combination and integration of both simulation and emulation for analysis and optimization purposes in a real automotive plant. A complete design of experiments has been done to assess different combinations of the simulation.

Results extracted from the Digital Twin approach show a reduction of 66% in commissioning (emulation) and reduction of 16% in cycle time losses (simulation).
Application of Artificial Intelligence to Solve an Elasto-Plastic Impact Problem
Authors: Chavan Shakti , Hor Hassan
Published: April 2021

Artificial intelligence (AI) is dramatically changing multiple industries. AI’s potential to transform Computer-Aided Engineering (CAE) cannot be overlooked. Conventionally, Finite Element Analysis (FEA) is the simulation of any given physical phenomenon to obtain an approximate solution to a group of problems governed by Partial Differential Equations (PDE). Implementation of AI methods in this area combines human intelligence with numerical solutions to make them more efficient. This paper attempts to develop a Deep Neural Network (DNN) model to solve an elasto-plastic impact problem of a symmetric short crush tube made of three materials impacted by a moving wall. A structured learning database was established to train and validate the model using finite element simulations. Tube size, gauge and elasto-plastic material properties were used as input attributes or features. The maximum axial displacement of the tube is the target label to predict. The dataset was analyzed to understand relations among the design features such as section size, gauge, and elasto-plastic material properties. The DNN model architecture and the hyper-parameters tuned to improve the model fit. The trained model was then evaluated with an unseen dataset to assess its prediction accuracy in real-world settings. The output of the DNN model was compared with the finite element simulation results. The established model shows a reasonable co-relation. Thus, this paper offers an alternative or a supplemental tool to conventional FEA methods to accelerate and augment design decision making. This paper offers an alternative or a supplemental tool to conventional FEA methods to accelerate and augment design decision making, and briefs an overall process to set up the Machine Learning (ML) model using TensorFlow and Python libraries. Finally, recommendations are made to propose potential research areas.
Stochastic Cycle to Cycle Prediction in a Reactivity Controlled Compression Ignition Engine Using Double Wiebe Function
Authors: Mishra Chinmaya , Subbarao P M V
Published: April 2021

The present paper proposed a cycle to cycle prediction of in-cylinder pressure profile using double Wiebe function in a reactivity controlled compression ignition (RCCI) engine. RCCI engines lack direct control over combustion by means of any explicit hardware such as fuel injection or spark timing. Therefore, cylinder pressure sensor based control or model driven control is necessary for RCCI engines. In this work, an iterative algorithm to generate double Wiebe function parameters, were designed to model cycle average measured cylinder pressure. The model and measured data were in good agreement. However, when, this model was compared with measured cycles, the error and regression exhibited a near normal distribution. The quality of error and regression was found to deteriorate with premix energy share (ES) in RCCI mode due to higher cycle to cycle variations. To address this challenge, a range of double Wiebe parameters were generated to mimic the inner and outer most pressure cycle at three times the standard deviation from the cycle average cylinder pressure (99.7% confidence interval). This parameter range was randomized using Gaussian distribution and model cycles were generated stochastically. Leveraging this modelling approach for realistic sensing of selected combustion control parameters, indicated robustness and reliability. The stochastic approach was found to be an innovative strategy for RCCI engine model driven control.
Experimental and 0D Numerical Investigation of Ultra-Lean Combustion Concept to Improve the Efficiency of SI Engine
Authors: De Bellis Vincenzo , Malfi Enrica , Bozza Fabio , KUMAR Deepak , Serrano David , Dulbecco Alessio , Zaccardi Jean-Marc
Published: April 2021

Recently, the car manufacturers are moving towards innovative Spark Ignition (SI) engine architectures with unconventional combustion concepts, aiming to comply with the stringent regulation imposed by EU and other legislators. The introduction of burdensome cycles for vehicle homologation, indeed, requires an engine characterized by a high efficiency in the most of its operating conditions, for which a conventional SI engine results to be ineffective. Combustion systems which work with very lean air/fuel mixture have demonstrated to be a promising solution to this concern. Higher specific heat ratio, minor heat losses and increased knock resistance indeed allow improving fuel consumption. Additionally, the lower combustion temperatures enable to reduce NOX production.

Since conventional SI engines can work with a limited amount of excess air, alternative solutions are being developed to overcome this constraint and reach the above benefit. Among all these solutions, replacing the spark-plug with a Pre-Chamber (PC) ignition system is gaining increasing interest. For this architecture, the combustion process starts in the PC and propagates in the main-chamber in the form of multiple turbulent jets of hot gas, with high-turbulence level. This ensures stable flame propagation even under extremely lean mixtures.

In this research activity, an ultra-lean PC SI engine is numerically and experimentally investigated to assess the potential improvement of the thermal efficiency for ultra-lean operations. To this aim, a research single cylinder engine, fuelled with gasoline, is tested at fixed load and speed, realizing an air / fuel ratio sweep. A 1D/0D model of the examined engine is implemented in a commercial modelling framework (GT-Power™), where “in-house developed” sub-models are embedded, simulating in-cylinder phenomena, such as combustion, turbulence, heat transfer and pollutant emissions.

The numerical approach, preliminarily tuned against 3D simulations and experimental outcomes, demonstrated to accurately reproduce the engine behaviour, without requiring any case-dependent tuning of the model constants. Both numerical and experimental results proved that working in ultra-lean condition allows to significantly improve the indicated thermal efficiency, abating the NOx emissions, while penalizing the HC production.
Controls and Hardware Development of Multi-Level Miller Cycle Dynamic Skip Fire (mDSF) Technology
Authors: Ortiz-Soto Elliott , Yang Xiaojian , Van Ess Joel , Owlia Shahaboddin , Joshi Abhishek , Younkins Matthew
Published: April 2021

mDSF is a novel cylinder deactivation technology developed at Tula Technology, which combines the torque control of Dynamic Skip Fire (DSF) with Miller cycle engines to optimize fuel efficiency at minimal cost. mDSF employs a valvetrain with variable valve lift plus deactivation and novel control algorithms founded on Tula’s proven DSF technology. This allows cylinders to dynamically alternate among 3 potential states designated as: High Fire, Low Fire, and Skip (deactivation). The Low Fire state is achieved through an aggressive Miller cycle with Early Intake Valve Closing (EIVC). The three operating states in mDSF can be used to simultaneously optimize engine efficiency and driveline vibrations. Acceleration performance is retained using the all-cylinder, High Fire mode. mDSF can be implemented cost-effectively using an asymmetric intake valve lift strategy, with one high-flow power charging port and one high-efficiency Miller port.

Prototype mDSF cylinder heads were based on the EA888 Gen 3B engine by retrofitting the valvetrain with asymmetric intake cams, deactivatable roller finger followers and two oil control valves per cylinder. Event-based engine controls were developed to enable for each cylinder dynamic selection of the three mDSF operating modes: High Fire, Low Fire and Skip. Appropriate air estimation, fuel control and ignition control techniques were employed to ensure acceptable torque delivery and tailpipe emissions.

Engine dynamometer tests showed a 23% reduction in engine fuel consumption at 1500 rpm, 2 bar NMEP. Maximum torque and power from the baseline production engine up to 5000 rpm were also achieved. mDSF vehicle tests on the WLTC demonstrated a 6% reduction in CO2 from Miller 2-step. Euro 6d compliant emissions were also reported. Further improvements in fuel economy, drivability and NVH may be possible by leveraging mixed firing densities more extensively.
Lean-Stratified Combustion System with Miller Cycle for Downsized Boosted Application - Part 2
Authors: Battiston Paul , Wheeler Jennifer , Solomon Arun , Sczomak David
Published: April 2021

Automotive manufacturers relentlessly explore engine technology combinations to achieve reduced fuel consumption under continued regulatory, societal and economic pressures. For example, technologies enabling advanced combustion modes, increased expansion to effective compression ratio and reduced parasitics continue to be developed and integrated within conventional and hybrid propulsion strategies across the industry. A high-efficiency gasoline engine capable for use in conventional or hybrid electric vehicle platforms is highly desirable. This paper is the second of two papers describing the multi-cylinder integration of a technology package combining lean-stratified combustion with Miller cycle for downsized boosted applications. The first paper describes the design, analysis and single-cylinder testing conducted to down-select the combustion system deployed to the multi-cylinder engine. This paper defines a light-duty engine package capable of achieving a 35% fuel economy improvement at US Tier 3 emission standards over a naturally aspirated stoichiometric baseline vehicle. A multi-mode combustion system was developed enabling highly efficient lean-stratified operation at light-load and stoichiometric Miller-cycle operation at mid- to high-loads. A central direct-injection four-valve layout was designed with high-tumble ports and a bowl-in-piston capable of stable operation under highly dilute mixtures when properly matched to fuel spray characteristics, injection strategy, and a high-energy ignition system. Boost system layout and base engine architecture were selected to minimize parasitics and maximize aftertreatment effectiveness. A multi-cylinder engine was developed and calibrated over a steady-state map. Results fed vehicle simulations over the EPA city and highway test cycles to predict the fuel economy improvement and tailpipe emissions potential. Fuel economy improvements over the baseline vehicle were projected at 42% and 39% for active-urea and passive-ammonia SCR aftertreatment systems respectively. Controls complexity to achieve regulatory compliance and the cost of the lean aftertreatment system were identified as the primary challenges to commercial viability.
Lean-Stratified Combustion System with Miller Cycle for Downsized Boosted Application - Part I
Authors: Solomon Arun , Battiston Paul , Sczomak David
Published: April 2021

Automotive manufacturers relentlessly explore engine technology combinations to achieve reduced fuel consumption under continued regulatory, societal and economic pressures. For example, technologies enabling advanced combustion modes, increased expansion to effective compression ratio, and reduced parasitics continue to be developed and integrated within conventional and hybrid propulsion strategies across the industry. A high-efficiency gasoline engine capable for use in conventional or hybrid electric vehicle platforms is highly desirable. This paper is the first to two papers describing the development of a combustion system combining lean-stratified combustion with Miller cycle for downsized boosted applications. The work was completed under a multi-year US DOE project. The goal was to define a light-duty engine package capable of achieving a 35% fuel economy improvement at US Tier 3 emission standards over a naturally aspirated stoichiometric baseline vehicle. A multi-mode combustion system was developed enabling highly efficient lean-stratified operation at light-load and stoichiometric Miller-cycle operation at mid- to high-loads. Some of the unique challenges in synergistically combining the two concepts are highlighted in this paper. A central direct-injection four-valve layout was designed with high-tumble ports and a bowl-in-piston capable of stable operation under highly dilute (lean plus EGR) mixtures when properly matched to fuel spray characteristics, a multiple-injection strategy, and a high-energy ignition system. Other challenges specific to meeting exhaust emissions requirements with a high-efficiency engine are also explored in this study. In this Part 1 of the paper, the single-cylinder combustion system design, analysis, and testing is described. Multi-cylinder engine system design, analysis and development is described in Part 2 of the paper [1].
Market Fuel Effects on Low Speed Pre-Ignition
Authors: Swarts Andre , Kalaskar Vickey
Published: April 2021

Low-Speed Pre-ignition (LSPI) is an undesirable abnormal combustion phenomenon observed in turbocharged, direct-injection spark-ignition engines and is characterized by early heat release, high cylinder pressures and severe, potentially damaging knock. LSPI has been studied for more than a decade and engine design, operating conditions and fuel and engine oil formulations have all been identified as contributing factors. A significant focus on engine oil has led to the establishment of the Sequence IX engine test and the second-generation of GM dexos® oil requirements, as well as a convergence of engine oil detergent causality. Conclusions about the effects of fuel on LSPI have been more varied, but as part of a recently completed research consortium, the LSPI tendency of market fuels with a range of properties, including composition, boiling point distribution, ethanol content and particulate matter index (PMI) were evaluated. Tests were performed in a 2-liter GM LHU engine and each test comprised of at least 24 repeats of a high-load, low-speed, steady-state test segment, with engine boundary conditions and calibration adjusted to amplify LSPI. All market fuel tests were bracketed by baseline tests and severity adjustments were made to account for changes in engine condition. It was found that the PMI and certain boiling points correlated the best with the frequency of LSPI events. In addition, decreased LSPI severity, quantified by the peak-to-peak knock values, was found to correspond with increased octane numbers and higher ethanol content of the market fuels.
Signal Reconstruction of Two-Color Pyrometry Technique Using CFD and a Detailed Spectral Radiation Model in a Marine Diesel Engine Setup
Authors: Geringer Stefan , Haworth Daniel , Boulouchos Konstantinos , von Rotz Beat , Bolla Michele , Mazzetta Marco
Published: April 2021

Optical soot pyrometry is a mature experimental technique that has been applied to a broad range of combustion systems for measuring soot temperature and concentration. Even though the method is widely used and well documented, the line of sight nature of the technique makes the interpretation of its results challenging. Notably, gradients in temperature and soot concentration along the line of sight or across the field of view can introduce significant levels of uncertainty in the results. This paper presents a numerical study where the signal from the experimental two-color pyrometry technique in a marine diesel engine reference experiment is reconstructed employing computational fluid dynamics (CFD) and a detailed Line-by-Line (LBL) spectral radiation model. The analysis is aimed at qualitatively supporting interpretability of experimental observations. Further, the role of soot and temperature gradients along and normal to the line of sight are assessed in two canonical configurations in which the signals are reconstructed numerically. In addition, the impact of different optical thicknesses is analyzed parametrically. The results obtained with the numerical pyrometry showed that gradients in temperature along the line of sight significantly affect the pyrometry temperature, leading to an overestimation of the effective soot averaged temperature in the range of 50 K to 250 K (i.e. 2-12%), depending on the soot concentration. Further, a saturation effect in the pyrometry KL-factor along the line of sight was observed at higher soot concentrations, resulting in an underestimation of the average soot volume by a factor of four to six in the canonical configurations. Gradients across the field of view were found to have a lower impact on the pyrometry results and to introduce much smaller biases than gradients along the line of sight.
A Computational Investigation of PPCI-Diffusion Combustion Strategy at Full Load in a Light-Duty GCI Engine
Authors: Zhang Yu , Sellnau Mark
Published: April 2021

A two-stage PPCI-diffusion combustion process recently showed good potential to enable clean and fuel-efficient gasoline compression ignition (GCI) combustion at medium-to-high loads. By conducting closed-cycle 3-D CFD combustion analysis, a further step was undertaken in this work to evaluate and optimize the PPCI-diffusion combustion strategy at a full load operating point (2000rpm-23.5 bar IMEPcc) while keeping engine-out NOx below 1 g/kWh.

The light-duty GCI engine used in this investigation featured a custom-designed piston bowl geometry at a 17.0 compression ratio (CR), a high pressure diesel fuel injection system, and advanced single-stage turbocharging. A split fuel injection strategy was used to enable the two-stage PPCI-diffusion combustion process.

First, the injector spray pattern and swirl ratio effects were evaluated. In-cylinder air utilization and the PPCI-diffusion combustion process were notably influenced by the closed-cycle combustion system design. Among the different spray patterns at a swirl ratio of 0, the one with 120° spray inclusion angle, 8-hole, and 1.5 times total nozzle area (TNA) was favored due to enhanced late-stage fuel-air mixing and more rapid diffusion combustion. In the second step, a fuel injection strategy optimization campaign was performed through a space-filling Design of Experiments (DoE) approach. Overall, the optimized injector spray pattern and the optimized fuel injection strategy together were predicted to produce 5.1% lower ISFC and 50% soot reduction over the baseline. A competitive analysis showed the optimized PPCI-diffusion combustion strategy had the potential to generate substantially lower NOx and soot than a modern light-duty diesel engine at full load.
Effect of Light Intensities on Growth Performance of Tetrapleura tetraptera Seedlings Schum. (Thonn.)
Authors: Ayeni O.D. , Onilude Q.A. , Adekola P.J. , Awosusi B.M. , Mba N.C. , Ogoliegbune U. , Okumodi B.O. , Audu M.A.
Published: April 2021

The study assessed the effect of varying light intensities and optimum percentage of sunlight favourable for raising Tetrapleura tetraptera seedlings. The light intensity was measured through photometer. The experiment was subjected to a control without wire mesh(T1) and three other treatments (T2, T3 and T4) covered with different layers of black wire mesh with 99.5%, 75%, 49.8% and 25% light intensities respectively. Each of the treatments was replicated six times in a completely randomized design. The plant height, leaf production and stem diameter were all monitored for 12 weeks. Analysis of Variance (ANOVA) was employed and the means separated using Least Significant Difference (LSD). The results showed that the significance effect (P = α0.05) was only observed in the seedlings height of Tetrapleuratetrapteraseedlings. However, the mean values obtained for all the parameters considered revealed the treatment 1(i.e. 99.8% wire mesh) was observed to be the best performing treatment. For the plant height, mean value ranged between 13.09 cm and 16.8 cm, a range from 0.22cm to 0.28mm was recorded for stem girth while the mean values between 22 and 27 were obtained for number of leaves among the treatments. It may be concluded from the study, that light intensity of 100% i.e without interference should be used for the growth and development as well as production of Tetrapleura tetraptera seedlings in the nursery.

Keywords: Growth development, light intensities, Tetraplura tetreptera seedlings, wire mesh size
Growth Evaluation of In-Vitro Propagated Embryo of Morinda Citrifolia L. Seeds
Authors: Afolabi J.O. , Adegboyega D.A. , Fasakin Y.O.
Published: April 2021

The dormant nature of Morinda citrifolia seeds is a limitation to its efficient in-vitro plantlet multiplication. Hence, the use of embryo culture for successful in-vitro culture initiation. Matured embryo of freshly collected noni seeds were cultured on Murashige and Skoog basal medium supplemented with kinetin (Kn) and Benzyl amino purine (BAP) in the range of A: control (no addition); B: 0.5 mg/l Kn+1.0 mg/l BAP; C: 1.0 mg/l Kn+2.0 mg/l Bap; D: 1.5 mg/l Kn+3.0 mg/l BAP and E: 2.0 mg/l Kn+4.0 mg/l BAP. The results at 4 weeks after inoculation (WAI) showed that germination was faster from medium A without hormone whereas highest percentage germination was obtained from both medium D and E with 80 %. Medium B and C had 65 % each while medium A gave the least (40%). The development of the plantlets showed that longest shoot (3.9 cm) from medium A was closely related to 3.58 cm from Medium B while root lengths (2.28 cm) and number of adventitious roots (26) from medium A were significantly higher than other media at 12 WAI. Highest number of nodes (2.25) obtained from medium D was comparable to Media C and B while medium A had the least at 12 WAI. Number of leaves obtained was similar between the media at 12 WAI. These results indicated that using embryo is reliable for fast in-vitro propagation and shoot development of noni plant with optimum cytokinins (0.5/1.0 mg/l Kn/BAP) application.

Keywords: Culture initiation, Cytokinins, Embryo culture, Plantlet, Shoot development
Investigation of Bulb Extracts of Crinum jagus for Antibacterial and Antifungal Activities
Authors: Alawode T.T. , Lajide L. , Owolabi B.J. , Olaleye M.T.
Published: April 2021

This study investigates the bulb extracts of Crinum jagus for antimicrobial activities. The bulb samples were dried, ground and subjected to successive extraction using hexane, ethylacetate and methanol. The extracts were screened for activity against Staphylococcus aureus, Escherichia coli, Bacillus subtilis, Pseudomonas aeruginosa, Salmonella typhi, Klebisidlae pneumonae, Candida albicans, Aspergillus niger, Penicillium notatum and Rhizopus stolonifer at concentrations between 6.25 and 200 mg/ml. Antimicrobial assays werecarried out using agar diffusion method. The Minimum Inhibitory Concentration (MIC) of the extracts was determined. The percentage yields obtained for the hexane, ethylacetate and methanol extracts of the bulbs are 0.28 %, 0.44% and 24.68 % respectively. Results showed that the methanolic extract had better antibacterial and antifungal activities than the other extracts. The methanol extract showed the highest antibacterial activity against S. aureus with a zone of inhibition of 28 mm at 200 mg/ml. Also, the methanol extract showed the highest antifungal activities against C. albicans, A. niger and P. notatum with a zone of inhibition of 20 mm at 200 mg/ml. The hexane and ethylacetate extracts had no activity against the microorganisms at 6.25 mg/ml.The methanol extract had the lowest Minimum Inhibitory Concentration (MIC) of 2.50 mg/ml against S. aureus, E. coli, B. subtilis, P. aeruginosa and S. typhi. The methanol extract could be a source of potent antimicrobial compounds.

Keywords: Antibacterial, Antifungal, Crinum jagus, Agar diffusion, MIC
Evaluation of Asa River Water in Ilorin, Kwara State, Nigeria for Available Pollutants and their Effects on Mitosis and Chromosomes Morphology in Allium cepa Cells
Authors: Akinboro A. , Peter N.A. , Rufai M.A. , Ibrahim A.O.
Published: April 2021

T: This study evaluated water samples from Asa River in Kwara state, Nigeria, for cytogenotoxicity at 25.0 %, 50.0 %, 100.0 % following the Allium cepa assay. Onions were grown in the water samples for microscopic and macroscopic screenings. Heavy metals and volatile organic pollutants in the water were elucidated using AAS and GCMS techniques. The Water samples except the sample ‘C’ induced higher mitotic index (MI) than the negative control. Root growth was significantly promoted at 25.0 %, and significantly reduced at 50.0 % and 100.0 % of the sample ‘C’ and 100.0 % of the sample ‘A’. Water sample ‘A’ (100.0%) induced highest percentage chromosomal aberrations (CA) while the water samples ‘B’ and ‘C’ induced higher percentage CA than the negative control. Cadmium was detected at a concentration higher than its permissible limit in drinking water. Poly aromatic hydrocarbons, Aromatic amines, Acridine dye, Phenolic and Polychlorinated compounds were detected in the water sample. The observed proliferative, inhibitory, cytotoxic and genotoxic effects of the water samples on A. cepa cells suggest that Asa river was polluted, having potential to adversely affect humans, animals and plants utilizing it along its course.

Keywords: Allium cepa; Asa River; cytogenotoxicity; Nigeria; pollutants
Antibiotic susceptibility pattern of Klebsiella pneumoniae and Pseudomonas aeruginosa isolated from some drinking wells in Ondo town southwest Nigeria
Authors: Aromolaran O. , Amodu O.A.
Published: April 2021

Antibiotic-resistant bacteria (ARB) strains have become a global health threat. This study aimed to determine the antibiotic susceptibility pattern of Klebsiella pneumoniae and Pseudomonas aeruginosa isolated from wells in Ondo town, Southwest Nigeria. Twenty-eight well water samples were analyzed for the presence of K. pneumoniae and P. aeruginosa by standard pour plate technique. The bacterial isolates were tested against eight commonly use antibiotics using Kirby Bauer disc diffusion method. The percentage occurrence of K. pneumoniae and P. aeruginosa in the well water samples were 17.86% and 21.43%, respectively. Two multi-drug resistant strains of K. pneumoniae were isolated, which were resistant to at least three classes of antibiotics. Fifty percent of the P. aeruginosa isolates were resistant to caftazidime, cefuroxime, nitrofurantoin, and ampicillin. None of the isolates was fully susceptible to cefuroxime, but have all showed resistance to β-lactam (ceftazidime, cefuroxime augmentin, and ampicillin) antibiotics. Cefuroxime may not be effective an effective drug in the treatment of K. pneumoniae and P. aeruginosa implicated infections in these communities in Ondo. Also, the over-use of antibiotics should be discouraged in order to curtail the menace of antibiotic resistance

Keywords: Well water, Antibiotics, Klebsiella pneumoniae, Pseudomonas aeruginosa
Effects of non-steroidal growth implant and dietary zilpaterol hydrochloride on growth and carcass characteristics of feedlot lambs
Authors: Webb E.C. , Allen J , Morris S.D.
Published: April 2021

The effects of steroidal growth implants alone or in combination with β-adrenergic agonist feed additives have not been studied thoroughly in mutton sheep in South African feedlot conditions. This study investigated the effects of a non-steroidal growth implant zeranol (Ralgro®), alone or in combination with zilpaterol hydrochloride (Zilmax®), on growth performance, carcass characteristics, and selected meat quality traits in 160 SA Mutton Merino ram lambs fed in a commercial feedlot. The experimental design consisted of two Ralgro treatment groups x two Zilmax treatments x two Zilmax feeding periods x 20 animals per treatment group. Lambs were randomly allocated to eight treatment groups, of which one half were implanted with Ralgro after arrival, followed by feed supplementation with Zilmax at two Zilmax feeding periods during the finisher phase, compared with negative control treatments (e.g. no Ralgro or Zilmax; Ralgro + no Zilmax; or no Ralgro + Zilmax). All lambs were fed the grower ration traditionally used by the commercial feedlot, which contained 16.89% crude protein (CP) and 2.94 Mcal/kg dry matter (DM). Zilmax was supplemented in the feed at 40 mg per animal per day and fed for 18 days or 25 days, plus three days withdrawal. Lambs that did not receive the Zilmax treatment were fed the basal diet without Zilmax feed supplementation. Ralgro significantly increased average daily gains (ADG) and cold carcass mass (CCM) of lambs. Lambs supplemented with Zilmax during the finisher phase had higher ADG, greater CCM and increased dressing percentage by ca.1.1% compared with those in the control group. Lambs fed Zilmax for 25 days had higher CCM than those fed for 18 days. The duration of the Zilmax treatment also decreased hide weight, fat thickness and shear force values (tenderness). Zilmax increased ADG and CCM in lambs, particularly if combined with Ralgro implants during the growing phase. The results from this study indicate that the combination of Ralgro implants with Zilmax feed supplementation during the finisher phase had additive effects and increased ADG and CCM of feedlot lambs.Keywords: Growth performance, meat quality, South African Mutton Merino, sheep, Ralgro®, Zilmax®
Predicting the growth and feed intake of Boer goats in a feedlot system
Authors: Brand T.S. , Van Der Merwe D.A. , Raffrenato E. , Hoffman L.C.
Published: April 2021

This research sought to develop a mathematical model to predict the growth and feed intake of Boer goat kids destined for slaughter. Data were collected from castrated kids that were housed in individual pens and fed diets that varied in energy content (11.3, 12.0, and 12.7 MJ metabolizable energy (ME)/kg feed). Growth and feed intake were monitored weekly for 20 weeks, from the time that the kids weighed 22.2 ± 3.5 kg until they were slaughtered at 48.3 ± 0.8 kg. The linear equation (bodyweight = 0.202 age – 5.241 (R2 = 0.84)) was found to predict the growth of kids between 126 and 266 days old. Correlations between expressions of intake and bodyweight were evaluated, cumulative feed intake and bodyweight being most highly correlated (r = 0.93). Linear models were developed to predict cumulative feed intake from bodyweight for goats fed each diet. Regression coefficients were compared between diets, with the slope of the equation for goats on the low energy diet (6.74 ± 0.25) being greater than that of the medium (5.80 ± 0.23) and high energy diets (5.82 ± 0.23). This indicates that goats on the medium and high energy diets gained weight more efficiently than those on the low energy diet. The results from this study can be used by goat producers to predict the growth and intake of goats and determine the ideal feedlot finishing period for optimal productivity.______________________________________________________________________________________Keywords: cumulative intake, dietary energy, modelling
Analysis of non-genetic and genetic influences underlying the growth of Kajli lambs
Authors: Ali A. , Javed K. , Zahoor I. , Anjum K.M.
Published: April 2021

Data on 2931 Kajli lambs, born from 2007 to 2018, were used to quantify environmental and genetic effects on growth performance of Kajli sheep. Traits considered for evaluation were birth weight (BWT), 120-day adjusted weight (120DWT), 180-day adjusted weight (180DWT), 270-day adjusted weight (270DWT), and 365-day adjusted weight (365DWT). Fixed effects of year of birth, season of birth, sex, birth type, and dam age on these traits were evaluated using linear procedures of SAS, 9.1. Similarly, BWT, 120DWT, 180DWT, and 270DWT were used as fixed effects mixed model analyses. Variance components, heritability and breeding values were estimated by restricted maximum likelihood. The genetic trend for each trait was obtained by regression of the estimated breeding values (EBV) on year of birth. Analyses revealed substantial influence of birth year on all traits. Sex and birth type were the significant sources of variation for BWT and 120DWT. Season of birth did not influence birth weight meaningfully, but had a significant role in the expression of 120DWT, 180DWT, and 270DWT. Heritability estimates were generally low (0.003 ± 0.018 to 0.099 ± 0.067) for all traits. With the exception of the genetic correlation of 180DWT and 365DWT, the genetic correlations between trait were strong and positive. Only 365DWT had a positive genetic trend. Although the heritability estimates for almost all weight traits were low, high and positive genetic correlations between BWT and other weight traits suggest that selection based on BWT would result in the improvement of other weight traits as a correlated response.Keywords: bodyweight, breeding value, genetic correlation, sheep
Supplementing diets for broilers that are low in crude protein and amino acids with protease
Authors: Sarica S. , Yurtseven S. , Polat I.
Published: April 2021

The study evaluated supplementation of broiler diets with a protease enzyme. Six hundred Ross 308 female broiler chicks were acquired at one day of age and randomly distributed to three treatments with five replicates of 40 chicks each. The experimental treatements consisted of i) a positive control diet with normal levels of crude protein, digestible lysine and digestible sulphur containing amino acids (PC); ii) a negative diet with reduced levels of crude protein, digestible lysine and digestible sulphur containg amino acids (NC); and iii) the NC diet augmented with Ronozyme ProAct protease at 200 mg/kg (NC+ENZY). Compared to the other diets, feeding the PC produced the highest final bodyweight (BW), bodyweight gain (BWG), and feed intake (FI) and best feed conversion ratio (FCR) over 0 - 42 days. The PC diet also produced the highest hot and cold carcass yields, ileal protein digestibility and improved the serum biochemistry parameters. Relative to the NC, the NC+ENZY diet increased BW, BWG and FI, improved FCR, increased ileal protein digestibility, hot and cold carcass yields, and the crude protein content of meat. However, it decreased serum triglyceride and very low density lipoprotein (VLDL) cholesterol levels and the crude fat content of meat of broilers. As a result, protease supplementation at the level of 200 mg/kg may not remove the detrimental effects that are caused by a 6% reduction in crude protein and digestible amino acids on performance, hot and cold carcass yields and ileal digestibility of crude protein of broilers.

Keywords: broiler, growth performance, low crude protein diet, meat, nutrient digestibility, protease, serum biochemistry parameters
Adding wheat and rapeseed meal to corn-soy diets affects intestinal morphology and nutrient digestibility in broilers
Authors: Amirahmadi E. , Safamehr A.R. , Nobakht A. , Mehmannavaz Y.
Published: April 2021

This study was conducted to investigate the effects of thyme essential oil and enzyme supplementation on rations with two different energy (wheat or corn) and protein resources (soy or rapeseed meals) on gut morphology and protein digestibility of broiler chickens. Three hundred eighty-four male Ross-308 broiler chickens were used with a 23 factorial arrangement with treatments according to a completely randomized design. The morphological examinations of the intestine were carried out on 1-cm long excised segments from duodenum, jejunum and ileum. Adding wheat to the diet increased small intestine length in birds compared to other feedstuffs (P <0.05). Duodenum crypt depth and jejunum villi length were also higher in groups fed with rations containing wheat (P <0.05). Groups that received thyme essential oil and enzyme supplementation had increased length of the duodenum (P <0.05). However, the two- and three-factor interaction effects were not significant. Protein digestibility was not affected by treatment (P >0.05). Feeding wheat to broiler chickens may increase the surface area for nutrient absorption in the small intestine as compensation for the anti-nutritive activity of non-starch polysaccharides in wheat-based diets. Wheat based diets are expected to be acceptable for broilers when supplemented with appropriate enzymes or thyme essential oil.
Boosting fish production in Cameroon: Incorporated fish-rice farming versus earthen pond fish culture in Buea, Mount Cameroon region
Authors: Oben B.O , Narika A.F , Arrey M.A , Ebobenow J , Oben M.P
Published: April 2021

Wetland incorporated fish-rice farming (FRF) is a possible solution to the problem of high costs of fish feeds in aquaculture in Cameroon. For 12 weeks, at the University of the Buea (UB) the growth of the fish, Clarias gariepinus in concurrent culture with rice (Oryza sativa, L.) in two rice plots (rice plot 1 and rice plot 2stocking sites) in the University of Buea wetland and in two earthen ponds (fish pond 1 and fish pond 2stocking sites) fed compounded diet at 5% body weight was investigated. Physico-chemical water quality parameters of all the fish culture sites were monitored. Mean fish weight gain was significantly higher (P<0.01) in the wetland rice plots (329.21±44.35g) than in the two earthen ponds (30.01±2.84g). Apart from low mean dissolved oxygen values in the rice plot 1 (3.14±1.19 mg/L) and rice plot 2 (2.18±0.23 mg/L), mean values for physico-chemical water quality parameters were within recommended ranges for C. gariepinus growth in all the four culture sites. This FRF experiment proved a better practice in fish growth than the conventional earthen pond culture in Buea, Cameroon. Its adoption by local fish farmers is recommended.

Keywords: Wetland integrated fish-rice farming, C gariepinus, earthen pond culture, and fishpond.
Antibiogram of faecal Streptococci isolates for pollution source determination in the Ikpoba river, Benin City
Authors: Sekegor C.O
Published: April 2021

Water samples from various sites of the Ikpoba River, Benin City, were bacteriologically analysed to determine bacterial indicators of faecal pollution and heterotrophic bacterial concentration. Sampling points 1 was the point of drainage discharge from the University of Benin Teaching Hospital, 2 was at the Bridge at Upper Mission Road, 3 was the point of effluent discharge from Oredo Local Government Area Abbatoir, 4 was at the Bridge along Benin-Agbor Road and 5 was the point of effluent discharge from Guinness Nigeria PLC. Faecal coliform count was generally high in all sample sites with the point of discharge of effluent from the Abbatoir showing the highest mean count of 1.51 × 107 cfu/ml; and the Bridge at Upper Mission Road had the lowest mean count of 1.20 × 107 cfu/ml. Faecal streptococci count was highest at the point of discharge of effluent from Guinness Nigeria PLC at 8.21 × 107 cfu/ml. while the Bridge at Upper Mission Road had the lowest faecal streptococcus count of 5.83 × 106 cfu/ml. Antibiotic Resistance Patterns of faecal streptococci isolates on day 1 were observed to be more susceptible to the battery of antibiotics than faecal streptococci isolates on days 2 and 3. The results of the ratio of faecal coliform to faecal streptococci and the antibiotic resistance pattern on faecal streptococci showed that faecal pollution of the Ikpoba River has both human and animal origin. There are undoubted risks to human health from surface water polluted with animal faeces, nevertheless, it is human faeces that represent a much greater risk and thus constant investigations should be carried out by environment monitoring agencies to evaluate the pollution status of the river and residents around the river should administer filtration techniques before domestic use.

Keywords: faecal pollution, faecal streptococci, antibiotic resistance patterns
Food items and feeding habits of two Nothobranchiidae, Epiplatys chaperi sheljuzhkoi (poll, 1953) and Nimbapanchax petersi (sauvage, 1882) in Banco river, Côte d’ivoire
Authors: Kouamé Ouanko D.A , Konan Y.A , Kamelan T.M , Gooré B.G , Gogbé Z.M
Published: April 2021

Food and feeding habits of two Nothobranchiidae species, Epiplatys chaperi sheljuzhkoi (Poll, 1953) and Nimbapanchax petersi (Sauvage, 1882) from Banco River were investigated between January and December 2016. Stomach contents of 119 and 397 individuals of E. sheljuzhkoi and N. petersi were respectively analyzed, ranging in size from 13 and 55 mm, 11 and 48 mm standard Length, respectively. Formicidae being terrestrial insects, constituted the main prey (RI>50) of both species, and aquatic insect larvae (Hydrophilidae and Chironomidae) were secondary or accessory preys. The food items in stomach showed a small spectrum in E. sheljuzhkoi than N. petersi but differences were not significant (Chi-square, p>0.05). Diet composition of both species showed little variation according to seasons, sampling zones and size groups (Anova, p>0.05). However, a decreasing trend in terrestrial insects and an increase of other preys in stomach contents has been observed from upstream to downstream. For ontogenic variation, large specimens group fed much more on aquatic insect larvae, fish scales and macrophytes than small size group. This work indicated that both species fed on a small range of prey items dominated by insects in Banco River and could be considered strict insectivorous predators. This work concludes that both species have similar diets and the canopy cover of Banco forest plays an important role in the feeding and conservation of these species.

Key words: Epiplatys, Nimbapanchax, canopy cover, diet, terrestrial insects, Formicidae, predator.
Niewykorzystany kapitał. Pomoc międzynarodowa a początki rehabilitacji zawodowej w Polsce po II wojnie światowej
Authors: Łotysz Sławomir
Published: April 2021

Unused Assets. International Aid and the Birth of Vocational Rehabilitation in Poland after the Second World War In 1946, at the request of the Polish government, UNRRA sent in two British experts in vocational rehabilitation to help establish the national framework of helping people with disabilities. During numerous meetings with government representatives, medical doctors, and social workers, as well as by trainings, lectures, and screenings of instructional films, they tried to familiarise Poles with the British model of rehabilitation. The model assumed close integration of medical and vocational rehabilitation and aimed at placing the disabled workers in the industry alongside those without disabilities. Initially, officials from the Polish Ministry of Labour and Social Welfare seemed to be keen to adopt such an approach, but in 1949, they turned toward the Soviet solutions. One of the main effects of this shift was moving away from employing the disabled in the industry. They were encouraged to join cooperatives instead, which, in the end, proved to be unfavorable to their social rehabilitation. The article reconstructs the activity of the British experts in Poland and analyses their observations from the encounters. By situating these events in a broader context of political and social conditions, I argue that replacing the progressive British model with Soviet solutions stemmed from the ongoing process of the Sovietization of Poland.
Nie tylko kurs historii naturalnej. Księżnej Anny Jabłonowskiej zbiór „wszystkich przedmiotów dociekań rozumu człowieka”
Authors: Arabas Iwona , Bondar Larysa , Czechowicz Lidia
Published: April 2021

Not Only a Natural History Course. Duchess Anna Jabłonowska’s “Collection of All Objects of Human Reason Inquiries”

One of the richest natural history collections in Europe at the end of the 18th century was the Cabinet of Natural History of Duchess Anna Jabłonowska née Sapieha (1728–1800) in Siemiatycze. In 1802, the collection was purchased by Tsar Alexander I and handed over to the University in Moscow (where it burned down in 1812). It was only possible to recreate the richness of the collection and the way it was taken over after the sales documents had been found in 2008 in the Archive of the Russian Academy of Sciences in St. Petersburg. However, some documents were illegible, and it was only in 2020 that the entire documentation was read. It revealed a completely different image of the collection than expected, as in one part the collection refers to cabinets of curiosities. The article is the first publication in Polish on Anna Jabłonowska’s “art cabinet”, with translations of the lists of exhibits by Count Stanisław Sołtyk (from French) and by V.M. Severgin and A.F. Sevastyanov (from Russian).
Recenzje
Authors: Gaidai Olga , Przeperski Michał
Published: April 2021

Olga Gaidai, Оксана Пилипчук, Київське юридичне товариство (1877–1919)[Oksana Pylypczuk, Kijowskie Towarzystwo Prawnicze (1877–1919)], Talkom, Kijów 2020, ss. 547

Michał Przeperski, Andrzej Friszke, Państwo czy rewolucja. Polscy komuniści a odbudowanie państwa polskiego 1892–1920, Wydawnictwo Krytyki Politycznej, Warszawa 2020, ss. 740