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Number of results: 49
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Abstract

So far, numerous studies have been published on the selection of appropriate maintenance tactics based on some factors affecting them such as time, cost, and risk. This paper aims to develop the TRIZ contradiction matrix by explaining the dimensions and components of each of the following Reactive maintenance tactics. The related findings of previous studies were analyzed by adopting “Rousseau and Sandoski” seven-step method to identify and extract the relationships between TRIZ principles and Reactive maintenance tactics. Thereafter, 5 Reactive maintenance tactics were replaced TRIZ’s 40 principles in the TRIZ contradiction matrix. Finally, the ANP method were used to extract and prioritize the appropriate Reactive maintenance tactics. The proposed matrix in this research was used in the desalination section of one of the oil companies to select on the appropriate Reactive maintenance tactics. The results of this research is useful for managers and maintenance specialists of units in making decisions to provide appropriate Reactive maintenance tactics for the desired equipment.
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Authors and Affiliations

Mohammad Amin Mortazavi
1
Atefeh Amindoust
1
Arash Shahin
2
Mehdi Karbasian
3

  1. Department of Industrial Engineering, Najafabad Branch, Islamic Azad University, Najafabad, Iran
  2. Department of Management, University of Isfahan, Isfahan, Iran
  3. Department of Industrial Engineering, Malek-Ashtar University of Technology, Isfahan, Iran
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Abstract

The article presents the consequences of the introduction of EU regulation 2016/631 for power park modules (PPMs), of which wind farms are a typical example. Analysing the yearlong course of changes in the generated power, the possibility of a typical wind farm meeting the requirements for the production and absorption of reactive power was checked. It was shown that in the selected cases it was necessary to introduce additional sources of reactive power on the side of the farm’s MV.

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Authors and Affiliations

Piotr Kacejko
Paweł Pijarski
Michalina Gryniewicz-Jaworska
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Abstract

In order to investigate the mechanism of adsorption of reactive dyes from the textile industry on ash from heating plant produced by brown coal combustion, some characteristic sorption constants are determined using Langergren adsorption equations for pseudo-fi rst and pseudo-second order. Combined kinetic models of pseudo-first order and pseudo-second order can provide a simple but satisfactory explanation of the adsorption process for a reactive dye. According to the characteristic diagrams and results of adsorption kinetic parameters of reactive dyes on ashes, for the applied amounts of the adsorbents and different initial dye concentrations, it can be concluded that the rate of sorption is fully functionally described by second order adsorption model. According to the results, the rate constant of pseudo-second order decreases with increasing initial dye concentration and increases with increasing amount of adsorbent – ash.

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Authors and Affiliations

Dragan Djordjevic
Dragan Stojiljkovic
Miodrag Smelcerovic
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Abstract

In the present study the adsorption of Reactive Blue 19 dye on the hydroxyapatite (HAp) nanopowders was investigated. The batch adsorption experiments were performed by monitoring the adsorbent dosage, contact time, dye solution concentration, pH and temperature. At pH 3 and 20°C, high dye removal rates of about 95.58% and 86.95% for the uncalcined and calcined nanohydroxyapatites, respectively, were obtained. The kinetic studies indicated the dye adsorption onto nanohydroxyapatite samples to follow a pseudo-second order model. The Langmuir isotherm was found to be the best to represent the equilibrium with experimental data. The maximum adsorption capacity of uncalcined and calcined nanohydroxyapatite samples has been found to be 90.09 mg/g and 74.97 mg/g, respectively.

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Authors and Affiliations

Gabriela Ciobanu
Simona Barna
Maria Harja
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Abstract

Single-branch filters are still popular and are commonly used for power quality improvement purposes. Analysis of a single-branch filter is a relatively simple task. Although individual filters tuned to specific harmonics can be easily designed, after connecting them into a group it turns out that the capacitance and inductance mutually influence each other, distorting the resulting frequency characteristics. This article presents a matrix method for design a group of single-branch filters, so that the resultant frequency characteristic satisfies the design requirements including the requirements for location of the frequency characteristic maxima. Designer indicates the frequencies of the parallel resonances.

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Authors and Affiliations

Ryszard Klempka
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Abstract

The levitation melting has a potentially wide range of applications, especially in the processing of reactive metals whose contact with the crucible material causes their contamination and damage to the crucible itself. Despite its advantages, levitation melting, already proposed in the 1920s, has not yet found significant use in industrial conditions. This is due to the nature of the electromagnetic field used in previously developed devices. The disappearance of this field in the system axis causes overcoming, in the case of larger charges, surface tension forces and metal leakage from the device. The article contains a comparative analysis of a conventional solution and a newly developed levitation melting device, whose completely different design eliminates the previous weight limit of the charge.

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Authors and Affiliations

S. Golak
B. Panic
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Abstract

Freedom and Resentment (1962), written by Peter Frederick Strawson, is one of the most influential papers in 20th century investigations regarding the problem of free will. An interesting criticism of that work was proposed by his son, Galen Strawson, who analyzed and rejected his father’s view, called the theory of reactive attitudes. In my paper I reconstruct the views of Peter Strawson and present counterarguments put forward by Galen Strawson. In the summary I suggest, following Robert Kane, that the disagreement may reflect some important changes in analytic philosophy.

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Authors and Affiliations

Jacek Jarocki
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Abstract

Self-esteem and emotional reactivity may be important personality determinants of human functioning in situations of social exposure. In this study, we compared the levels of these personality variables in a group of professional theater actors and a group of professional illusionists with a control group of participants who were neither actors nor illusionists and had no artistic education. We also examined the correlations between emotional reactivity and self-esteem in the three groups. For emotional reactivity, we found (1) very strong evidence that the level is less for magicians than for controls, (2) substantial evidence that the level is less for magicians than for actors, (3) anecdotal evidence that the level is less for actors than for controls, and (4) decisive evidence that the average score is less for males than for females. For self-esteem, we found (1) anecdotal evidence that the level is higher for magicians than for controls, (2) substantial evidence that there is no difference between actors and magicians, (3) anecdotal evidence against a difference between actors and controls, and (4) anecdotal evidence against a difference between males and females. Based on the entire sample we found a moderate correlation between self-esteem and emotional reactivity (r = -.30, p < 0.001). Our results are compatible with the notion that emotional reactivity – as part of the temperament concept – is a factor influencing the choice of an artistic profession.
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Authors and Affiliations

Wojciech Napora
1
Vebjørn Ekroll
2

  1. Jan Dlugosz University in Częstochowa, Poland
  2. University of Bergen, Norway
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Abstract

This paper proposes a fair calculation approach for the cost and emission of generators. Generators also have reactive power requirements along with the active power demand to meet up the total power demand. In this paper, firstly the reactive power is calculated considering the random active power operating points on the capability curve of a generator then the cost for reactive power generation as well as emission are calculated. In order to develop the mathematical function for the reactive power cost and reactive power emission, a curve-fitting technique is applied, which gives the generalised reactive power cost and reactive power emission functions. At the end, the problem is formulated as a multiobjective problem, considering conflicting objectives such as combined active- reactive economic dispatch and combined active-reactive emission dispatch. The problem is converted from the multiobjective load dispatch problem (MOLDP) into a scalar problem, using the weighting method and the best compromised solution has been calculated using the particle swarmoptimization (PSO) technique.Afuzzy cardinal method has been applied to choose the best solution. In order to demonstrate the efficiency of developed functions the proposed method is applied on a 3 generator unit system and a 10 generator unit system, the results obtained show its validity and effectiveness.

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Authors and Affiliations

Harinder Pal Singh
Yadwinder Singh Brar
D.P. Kothari
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Abstract

Silver nanoparticles (AgNPs) are widely used in numerous industries and areas of daily life, mainly as antimicrobial agents. The particles size is very important, but still not suffi ciently recognized parameter infl uencing the toxicity of nanosilver. The aim of this study was to investigate the cytotoxic effects of AgNPs with different particle size (~ 10, 40 and 100 nm). The study was conducted on both reproductive and pulmonary cells (CHO-9, 15P-1 and RAW264.7). We tested the effects of AgNPs on cell viability, cell membrane integrity, mitochondrial metabolic activity, lipid peroxidation, total oxidative and antioxidative status of cells and oxidative DNA damage. All kinds of AgNPs showed strong cytotoxic activity at low concentrations (2÷13 μg/ml), and caused an overproduction of reactive oxygen species (ROS) at concentrations lower than cytotoxic ones. The ROS being formed in the cells induced oxidative damage of DNA in alkaline comet assay. The most toxic was AgNPs<10 nm. The results indicate that the silver nanoparticles, especially less than 10 nm, may be harmful to the organisms. Therefore, risk should be considered when using nanosilver preparations and provide appropriate protective measures when they are applied.

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Authors and Affiliations

Lidia Zapór
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Abstract

Recently, there has been research on high frequency dissipative mufflers. However, research on shape optimization of hybrid mufflers that reduce broadband noise within a constrained space is sparse. In this paper, a hybrid muffler composed of a dissipative muffler and a reactive muffler within a constrained space is assessed. Using the eigenvalues and eigenfunctions, a coupling wave equation for the perforated dissipative chamber is simplified into a four-pole matrix form. To efficiently find the optimal shape within a constrained space, a four-pole matrix system used to evaluate the acoustical performance of the sound transmission loss (STL) is evaluated using a genetic algorithm (GA).

A numerical case for eliminating a broadband venting noise is also introduced. To verify the reliability of a GA optimization, optimal noise abatements for two pure tones (500 Hz and 800 Hz) are exemplified. Before the GA operation can be carried out, the accuracy of the mathematical models has been checked using experimental data. Results indicate that the maximal STL is precisely located at the desired target tone. The optimal result of case studies for eliminating broadband noise also reveals that the overall sound power level (SWL) of the hybrid muffler can be reduced from 138.9 dB(A) to 84.5 dB(A), which is superior to other mufflers (a one-chamber dissipative and a one-chamber reactive muffler). Consequently, a successful approach used for the optimal design of the hybrid mufflers within a constrained space has been demonstrated.

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Authors and Affiliations

Min-Chie Chiu
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Abstract

Asynchronized (doubly-fed) machines with two (three) excitating winding and reversing excitation system allow to control vector of magnetomotive force. This solution allows separating regulation of the electromagnetic torque (active power) and voltage (reactive power). This paper describes the experience in the development and operation of asynchronized turbogenerators and condensers.

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Authors and Affiliations

Yury Shakaryan
Pavel Sokur
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Abstract

With the increasing penetration rate of grid-connected renewable energy generation, the problem of grid voltage excursion becomes an important issue that needs to be solved urgently. As a new type of voltage regulation control method, electric spring (ES) can alleviate the fluctuations of renewable energy output effectively. In this paper, the background and basic principle of the electric spring are introduced firstly. Then, considering the influence of an electric spring on noncritical load voltage, noncritical loads are classified reasonably, and based on the electric spring phasor diagram, the control method to meet the noncritical load voltage constraint is proposed. This control method can meet the requirements of voltage excursions of different kinds of noncritical load, increase the connection capacity of the noncritical load and improve the voltage stabilization capacity of the electric spring. Finally, through the simulation case, the feasibility and validity of electric spring theory and the proposed control method are verified.

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Authors and Affiliations

Yixi Chen
Gang Ma
Uchao Xu
Hang Zhang
Rong Ju
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Abstract

The presented paper concerns the issues of communication networks applied to monitoring and control of reactive power compensator for small hydroelectric plants installed in areas distant from urban agglomerations. Ethernet, CAN, Modbus and GPRS transmission protocols has been used. Industrial programmable controller as a data collector has been used also.

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Authors and Affiliations

Remigiusz Olesiński
Paweł Hańczur
Janusz Wiśniewski
Włodzimierz Koczara
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Abstract

Allelopathy refers to the beneficial and detrimental effects of one plant on another plant in both crops and weeds through the production of secondary compounds. In order to evaluate the allelopathic effects of wheat ( Triticum aestivum L.) as a crop and redroot pigweed ( Amaranthus retroflexus L.) as a common weed worldwide on each other in intercropping, these plants were cultivated under controlled conditions at Tabriz University laboratory. The ratios of wheat to redroot pigweed were, 100 : 0 and vice versa as a control, 75 : 25, 50 : 50, and 25 : 75. The results showed that at the ratio of 25 : 75 (wheat : redroot pigweed), the fresh and dry weight of roots and shoot length of wheat decreased significantly compared to the control. The fresh and dry weight of wheat shoots showed a significant decrease at different ratios compared to the control. Shoot peroxidase (POD), root superoxide dismutase (SOD), and root and shoot catalase (CAT) activities in redroot pigweed increased in all intercropping ratios compared to the control. POD activity in wheat roots was higher at all ratios than in the control. Furthermore, the ratio of 75 : 25 (wheat : redroot pigweed) led to increased activity of POD enzymes and malonedialdehyde (MDA) content in wheat shoots. Moreover, roots of redroot pigweed showed increased activity of ascorbate peroxidase (APX) and SOD enzymes and MDA content. With increased density of redroot pigweed, the soluble sugar content of wheat roots reduced significantly. However, the content of insoluble sugar and total protein increased. Root exudate compounds such as terpenoids, phenolic compounds, fatty alcohol, steroids, fatty acids, and alkanes were identified using gas chromatography/mass spectrometry (GC/MS). The findings showed that the roots were more exposed to oxidative stress due to direct contact with allelochemical compounds. Our results support the hypothesis that increasing the density can reduce the toxicity of allelochemical compounds and that increasing the activity of the antioxidant system will improve plant growth under allelochemical stress.
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Authors and Affiliations

Zahra Alizadeh
1
ORCID: ORCID
Rouhollah Motafakkerazad
1
ORCID: ORCID
Seyed Yahya Salehi-Lisar
1
Gholamreza Zarrini
2

  1. Plant, Cell and Molecular Biology Department, Faculty of Natural Sciences, University of Tabriz, Tabriz, Iran
  2. Animal Biology Department, Faculty of Natural Sciences, University of Tabriz, Tabriz, Iran
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Abstract

The paper aims at the higher reactive power management complexity caused by the access of distributed power, and the problem such as large data exchange capacity, low accuracy of reactive power distribution, a slow convergence rate, and so on, may appear when the controlled objects are large. This paper proposes a reactive power and voltage control management strategy based on virtual reactance cloud control. The coupling between active power and reactive power in the system is effectively eliminated through the virtual reactance. At the same time, huge amounts of data are treated to parallel processing by using the cloud computing model parallel distributed processing, realize the uncertainty transformation between qualitative concept and quantitative value. The power distribution matrix is formed according to graph theory, and the accurate allocation of reactive power is realized by applying the cloud control model. Finally, the validity and rationality of this method are verified by testing a practical node system through simulation.

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Authors and Affiliations

Wei Min Zhang
Yan Xia Zhang
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Abstract

Catalytic reforming is an important intermediate in the processing of crude (naphtha in particular) to obtain gasoline. The catalyst used in the process (platinum) is quite expensive and may negatively impact the business if not used judiciously. The aforesaid not only refers to the reduction in loss of the catalyst per unit of gasoline produced but also to the manufacturing of an environmentally friendlier product alongside which is the need of the planet and also a necessity to meet the increasingly strict government norms. In order to meet the above requirements, various refineries around the world use various well-known conventional methods which depend on the quality and quantity of crude manufactured by them.
This paper focuses on highlighting recent advancements in methods of catalytic regeneration (CR) in the reforming unit of petroleum industries to produce high octane gasoline, without any major replacements in their existing setup. Research papers formulated by the application of methodologies involving non-linear models and real-time refinery data have only been considered to avoid any deviations/errors in practical applications. In-depth analysis of these papers has led to the origin of some ideas which have been included as suggestions and can be considered as subjects of further research. In all, the objective of the paper is to serve as a reference for researchers and engineers working on devising optimum methods to improve the regeneration of reforming catalysts.
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Authors and Affiliations

Aviral Gupta
1
S.K. Gupta
1

  1. Harcourt Butler Technical University, Department of Chemical Engineering, Kanpur-208002, India
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Abstract

The paper focuses on two research objectives. First, it aims to critically examine a reductio ad absurdum argument against incompatibilism whose main themes can be found in Peter F. Strawson’s Freedom and Resentment. The doubts raised about the argument are inspired by a thought experiment based on fictitious Ludovico’s technique described in Anthony Burgess’s novel A Clockwork Orange. The second objective consists in outlining a version of the compatibilist stance – the version which is immune to Strawson’s objections against the traditional rendering of compatibilism and enables deeper understanding of various possible interpretations of the controversy between compatibilists and their opponents. The proposed position includes a hypothesis on the function of the attitude of participation and the expressivist explications of the concepts crucial for the practice of ascribing moral responsibility. The important feature of the analyses in question is the central role of the states of mind whose content are plans for reactive moral sentiments.

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Authors and Affiliations

Adrian Kuźniar
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Abstract

The article presents Peter F. Strawson’s remarks on the free will debate, which he has presented in the essay ‘Freedom and Resentment’. Strawson avoids taking a stance on the question whether the thesis of determinism is correct. Instead he shows the essential difficulties and far reaching consequences of acknowledging this thesis. He recognizes the inseparable connection between freedom and responsibility in the philosophy after Kant. He consequently questions whether we really understand what it would mean to claim that determinism is true. He focuses on what he calls ‘reactiv attitudes’ triggered by the way in which other people behave toward us. Their behavior evokes emotional reaction in us – gratitude, respect, curiosity, but also distrust, resentment, disappointment. Those emotional responses are not purely subjective and they underlie moral judgments and complicated interpersonal relations. We suspend our reactive attitudes towards animals, very small children or people that we think are mentally ill. Instead we adopt objective (psychiatric, scientific) attitudes towards them. But to acknowledge the thesis of determinism implicates that we should treat all people this way. The paper is not so much concerned with an analysis of advantages and weak points of Strawson’s version of compatibilism, but focuses instead on the originality of his contribution to the debate on free will and on his brilliant treatment of reactive attitudes.

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Authors and Affiliations

Karolina Rychter
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Abstract

The paper is the second part of the work, devoted to a DC power supply with a power factor correction function. The power supply is equipped additionally with a shunt active power filter function, which enables the compensation of reactive and distortion power, generated by loads, connected to the same power grid node. A tunable inductive filter, included at the input of the power electronics current source – the main block of the power supply – allows for an improvement of the quality of the system control, compared to the device with a fixed inductive filter. This improvement was possible by extending the current source “frequency response”, which facilitated increasing the dynamics of current changes at the power supply input. The second part of the work briefly reminds the reader of the principle of operation and the structures of both the power supply control system and its power stage. The main purpose of this paper is to present the selected test results of the laboratory model of the electric system with the power supply.
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Bibliography

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Authors and Affiliations

Michał Gwóźdź
1
ORCID: ORCID
Rafał Wojciechowski
1
ORCID: ORCID
Łukasz Ciepliński
1
ORCID: ORCID

  1. Poznan University of Technology, Faculty of Control, Robotics and Electrical Engineering, Piotrowo 3A, 60-965 Poznan, Poland
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Abstract

The aim of this study was to measure serum neopterin and C-reactive protein (CRP) concen- trations in female dogs with mammary tumours and evaluate the association between the values of these indicators and some clinical characteristics of the tumour. Fifty three female dogs were used for this study, including 43 dogs with mammary gland tumours (10 benign and 33 malignant) and 10 healthy controls. The concentrations of neopterin and CRP were determined using the ELISA technique and commercial ELISA kits. The mean serum neopterin concentration in fe- male dogs with mammary tumours was lower than in healthy dogs, but significant difference was not found. Similarly, there were no significant differences in neopterin concentrations in female dogs based on tumour size, tumour ulceration and metastasis. The mean CRP concentration was significantly higher (p<0.05) in dogs with malignant tumours compared to dogs with benign tu- mours and control. Furthermore, serum CRP concentration was significantly higher (p<0.05) in dogs with metastatic malignant tumours compared to dogs with non-metastatic mammary tu- mours. The CRP concentration was significantly lower (p<0.05) in dogs with tumours less than 3 cm compared to those with larger tumours, and significantly higher in dogs with ulcerated tu- mours compared to those without ulceration. Our findings suggest that the neoplastic process in the mammary gland does not cause significant changes in serum neopterin concentrations in dogs. Higher concentrations of serum CRP in dogs with advanced stages of malignant tumours may suggest that CRP could be a potential prognostic marker in canine malignant mammary tu- mours, but this hypothesis needs further study.

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Authors and Affiliations

M. Szczubiał
R. Dabrowski
W. Łopuszyński
M. Bochniarz
M. Krawczyk
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Abstract

The work presents a DC power supply with power factor correction (PFC). This device is also equipped with a parallel active filter function, which enables the possibility of compensation (minimization) of reactive and distortion power, generated by a group of loads, connected to the same power grid node. A passive filter with variable inductance applied at the input of the power supply allows for a significant improvement in quality of the system control (given specific criteria), as compared to the solution with a filter with fixed parameters. This is possible by increasing the dynamics of current changes at the power supply input (extending its “frequency response”). The paper presents the principle of operation as well as structures and models of the power supply control system and its power stage. Selected test results of the simulation model of the electric system with the power supply, in various operating conditions, are also presented.

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Authors and Affiliations

M. Gwóźdź
Ł. Ciepliński
M. Krystkowiak
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Abstract

Reactive powder concrete (RPC), due to its characteristic composition with reduced water quantity, often below a stoichiometric ratio, the addition of pozzolana usually close to or above 20% of the weight of cement and a significantly reduced inclusion rate compared to normal or high performance concrete, has a different nature of the interfacial transition zone between the micro aggregate grains and the binder matrix. Due to the significant influence of RPC curing conditions on the morphology of the interfacial transition zone, the analysis included composites cured in water of Tmax=20°C, subject to low-pressure steam curing Tmax=90°C and autoclaved at Tmax=250°C. The paper presents a qualitative assessment of the interfacial transition zone in reactive powder concretes with the use of a scanning microscope with the use of linear EDS and quantitative analysis by means of stereological analysis of the image obtained with the use of a BSE detector. The results of the study unequivocally confirm the lack of portlandite crystallisation at the phase interface and the different phase composition in the interfacial transition zone in relation to the mean mass composition.

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Authors and Affiliations

Tomasz Zdeb
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Abstract

Drug-abuse detection tests are becoming increasingly commonplace in patient care today and provide a rapid and effective method for identifying illicit substances. Occasionally, they may yield a positive result, indicating the presence of a substance, even though the individual has not consumed the suspected drug what sometimes can significantly impact both medical and legal decisions. The study outlines the substances that can lead to false-positive drug test results for amphetamines, cannabinoids, and benzodiazepines. The study’s findings have revealed pivotal insights for patients receiving chronic treatment and their primary care physicians. Notably, amphetamine assays appear to be most prone to cross-reactivity with other substances. The beta-blocker group of medications, confirmed by various studies to interfere with amphetamine assays, could pose a substantial challenge in drug screening given its widespread use. Efavirenz also warrants mention, as it frequently triggers positive results for both benzodiazepine and cannabinoid assays among its users. This research helps highlight new areas for further investigation and aims to guide clinicians in their daily practice, especially when interpreting questionable positive drug-abuse test results. This comprehensive review serves as a valuable resource for clinicians to navigate false-positive scenarios effectively and maintain the highest standard of patient care.
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Authors and Affiliations

Kamil Możdżeń
1
Konrad Kaleta
1
Agnieszka Murawska
1
Jakub Pośpiech
1
ORCID: ORCID
Piotr Panek
1
Barbara Lorkowska-Zawicka
2
Beata Bujak-Giżycka
2

  1. Student Scientific Group of Clinical Pharmacology, Jagiellonian University Medical College, Kraków, Poland
  2. Depatment of Clinical Pharmacology, Jagiellonian University Medical College, Kraków, Poland

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