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Electrospinning is a very interesting method that allows the fabrication of continuous fibers with diameters down to a few nanometers. This paper presents an overview of electrospinning systems as well as their comparison using proposed three-dimensional parameterized numerical models. The presented solutions allow an analysis of the electric field distribution.

Design and control of electric motors in such a way as to ensure the expected motor dynamics, are the problems studied for many years. Many researchers tried to solve this problem, for example by the design optimization or by the use of special control algorithms in electronic systems. In the case of low-power and fractional power motors, the manufacture cost of the final product is many times less than cost of electronic system powering them. The authors of this paper attempt to improve the dynamic of 120 W line-start synchronous reluctance motor, energized by 50 Hz mains (without any electronic systems). The authors seek a road enabling improvement of dynamics of the analyzed motor, by changing the shape and material of the rotor, in such a way to minimize the modification cost of the tools necessary for the motor production. After the initial selection, the analysis of four rotors having different tooth shapes, was conducted.

Electrospinning is an experimental method of the polymer super thin fibres formation using the electrostatic field. The distribution of electrostatic field affects the effectiveness of the electrospinning. In order to analyse the electrostatic field for given technological parameters the 3-D computer model of an electrospinning device must be applied.

Since their discovery by Iijima in 1991 [1], carbon nanotubes have sparked unwavering interest among researchers all over the world. This is due to the unique properties of carbon nanotubes (CNTs). Carbon nanotubes have excellent mechanical and electrical properties with high chemical and thermal stability. In addition, carbon nanotubes have a very large surface area and are hollow inside. This gives a very broad spectrum of nanotube applications, such as in combination with polymers as polymer composites in the automotive, aerospace or textile industries. At present, many methods of nanotube synthesis are known [2, 3, 4, 5, 6]. It is also possible to use carbon nanotubes in biomedical applications [7, 8, 9, 10, 11, 12, 13, 14], including the destruction of cancer cells using iron-filled carbon nanotubes in the hyperthermia process. Computer modelling results of Fe-CNTs induction heating process are presented in the paper. As an object used for computer model creation, Fe-CNTs were synthesized by the authors using CCVD technique.

A fan with cycloidal rotor (CRF) becomes a popular idea in wide application such as aviation, HVAC (heat, ventilation and air conditioning) or marine propeller systems. This is due to advantages such as direct control of the flow direction, larger flow rates than in a conventional machines without cycloidal control. In the presented article, velocity fields of CRF placed in a rectangular channel was measured, using Laser Doppler Anemomentry (LDA) method and thermoanemometric probe (TA).

The aim of this article is to thoroughly analyse the influence of condensation models on the modelling of condensation phenomena in transonic flow of moist air. The reason for the study was the fact that different condensation models are used by researchers to obtain satisfactory results of numerical modelling. The condensation models tested herein differ in the nucleation rate formula and the droplets growth equation. Four most often used condensation models were selected for detailed investigations. The results obtained from each model were compared with experiments for the nozzle flow. The main focus was on the location of the onset of the nucleation process. Moreover, the droplets growth intensity was compared and discussed. The nozzle flow CFD calculations were performed using the ANSYS Fluent commercial tool. Finally, the condensation model which is the most suitable for the moist air transonic flow was recommended.

For many years, the Department of Power Engineering and Turbomachinery of the Silesian University of Technology has been using a small-capacity (about 500 kWe) steam-gas power plant. Based on many years of experience in operation of this power plant utilizing the Velox-type gas-steam system, an idea arose to modify this type of thermal power cycle to create a combined heat and power (CHP) plant of small capacity, dedicated for distributed heat and power production or production process steam with high temperature. Previous thermodynamic and economic analysis of that type of low-power CHP plant confirmed many advantages of using this type of solution in low-power engineering. The new idea is to add a throttle valve between the economizer and the evaporator for the reference cycle of the gas-steam Velox-type CHP plant. It was further assumed that water would partially be vaporized on the valve. This paper presents a thermodynamic and economic analysis of this type of a system with an added throttle valve. Downstream the valve, the evaporated water fraction is fed directly into the steam superheater. It is determined how such a retrofit affects the system thermodynamic and economic characteristics. The system is modelled in the EBSILON® Professional 14 software.

The experimental research, initiated at the Institute of Power Engineering and Turbomachinery of the Silesian University of Technology at the end of the last century, created an opportunity to supplement knowledge about the phenomenon of steam flow with condensation, tested by numerical fluid mechanics by IMiUE employees. In parallel with the numerical work, significant progress has been made in experimental studies on thflow of wet steam. Recently, measuring techniques based on recording the phenomenon of extinction of light have been elaborated or improved. The basic value determined in the final stage in the experimental way was the contentof the liquid phase defined as the wetness fraction. The methodology of tests and experimental investigations was presented, as well as the applied and developed measurement systems. Next, some developed designs of X probe and their modifications are described. Article present also some examples of applications of the developed measurement techniques in application to experimental research conducted on wet steam in the IMiUE. Examples of comparison between experimental and numerical tests are also provided.

For many years, the Institute of Power Engineering and Turbomachinery of the Silesian University of Technology has been using a small-capacity (about 500 kWe) steam-gas power plant. Based on many yearsof experience in operation of this power plant utilizing the Velox-type gas-steam system, an idea arose to modify this type of thermal power cycle to create a combined heat and power (CHP) plant of small capacity, dedicated for distributed heat and power production of the range up to 500 kW or production process steam with high temperature. Previous thermodynamic and economic analysis of that type of CHP plant were conducted for natural gas as afuel. The new idea is use the alternative gas fuels or waste heat for Velox-type CHP plant. An adaptation of the Velox-type CHP plant for various fuelscan be done in simple way by moving the combustion chamber out from the setof heat exchangers, in similar way as it is done for HRSG. This paper presents a thermodynamic analysis of the Velox-type steam-gas cycle fired with various alternative gas fuels such as coke gas, blast furnace gas, biogas orgas from gasification. The systems are modelled in the EBSILON® Professional 13 program.

The present paper describes an experimental and numerical study of steam condensing flow in a linear cascade of turbine stator blades. The experimental research was performed on the facility of a small scale steam power plant located at Silesian University of Technology in Gliwice, Poland. The test rig of the facility allows us to perform the tests of steam transonic flows for the conditions corresponding to these which prevail in the low-pressure (LP) condensing steam turbine stages. The experimental data of steam condensing flow through the blade-to- blade stator channel were compared with numerical results obtained using the in-house CFD numerical code TraCoFlow. Obtained results confirmed a good quality of the performed experiment and numerical calculations.

Introduction: Radiation induced lymphopenia (RIL) deteriorate survival and diminishes the benefit of immune checkpoint inhibitors in combined treatment of lung cancer. Given the inconsistent data across various studies on the predictors of RIL, we aim to methodically elucidate these predictors and formulate a practical guide for clinicians., Methods: We conducted observational cohort study in four tertiary cancer centers. Patients with non-small cell lung cancer and small cell lung cancer, without lymphopenia grade >1, who underwent standalone radiotherapy (RT) in minimum 15 fractions were eligible. Dose-volume parameters of structures and clinical factors were comprehensively analyzed using various predictors selection methods and statistical models (Linear Regressors, Elastic Net, Bayesian Regressors, Huber Regression, regression based on k-nearest neighbors, Gaussian Process Regressor, Decision Tree Regressor, Random Forest Regressor, eXtreme Gradient Boosting, Automated Machine Learning) and were ranked to predict lymphocytes count nadir (alc_nadir)., Results: Two hundred thirty eight patients (stage I-3.4%, II-17.6%, III-75.2%, IV-3.8%) who underwent RT to median dose of 60 Gy were analyzed. Median alc_nadir was 0.68K/mm 3 . The 60 feature sets were evaluated in 600 models (RMSE 0.27-0.41K/mm ³ ). The most important features were baseline lymphocyte count (alc_1), mean lung_dose, lung v05, lung v10, heart v05 and effective dose to immune cells (edic). In patients with alc_1 ≤ 2.005K/mm 3 , median alc_nadir predictions were 0.54K/mm3 for lung_v05p > 51.8% and 0.76K/mm 3 for lung_v05p ≤ 51.8%. Lymphopenia was rare in patients with alc_1 > 2.005K/mm 3 ., Discussion: RIL was most severe in patients with low early lymphocyte counts, primarily triggered by low RT doses in the heart and lungs., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Kuncman, Pajdziński, Smółka, Bilski, Socha, Stando, Peszyńska-Piorun, Korab, Jereczek-Fossa and Fijuth.)

Permanent Magnet (PM) Brushless Direct Current (BLDC) actuators/motors have many advantages over conventional machines, including high efficiency, easy controllability over a wide range of operating speeds, etc. There are many prototypes for such motors; some of them have a very complicated construction, and this ensures their high efficiency. However, in the case of household appliances, the most important thing is simplicity, and, thus, the lowest price of the design and production. This article presents a comparison of computer models of different design solutions for a small PM BLDC motor that uses a rotor in the form of a single ferrite magnet. The analyses were performed by using the finite element method. This paper presents unique self-defined parts of basic PM BLDC actuators. With their help, various design solutions were compared with the PM BLDC motor used in household appliances. The authors proved that the reference device is the lightest one and has a lower cogging torque compared to other actuators, but also has a slightly lower driving torque.

Objectives: Vestibular rehabilitation leads to a gradual diminution of the subjective and objective symptoms that accompany the vestibular disorders. The aim of the study was to compare the impact of 2 different types of vestibular rehabilitation on vestibular compensation in patients with chronic unilateral vestibular dysfunction., Material and Methods: The study was conducted on a group of 58 subjects (43 females and 15 males) aged 40-64 years, who presented with chronic unilateral vestibular dysfunction and were hospitalized. The patients were randomly assigned to either of the 2 groups established. The study was conducted in a 6-week period. Group 1 consisted of patients who underwent customized group vestibular rehabilitation in an outpatient setting. The program was performed once a week for 1 h 30 min, under the supervision of a physiotherapist and a physiatrist. Group 2 was instructed to perform Cawthorne-Cooksey exercises and simple balance exercises twice a day for 15 min., Results: An improvement in the outcomes of the Dynamic Gait Index as well as the Berg Balance Scale was statistically significant for group 1. The time for fulfilling the task in the Timed Up and Go Test improved in both groups (p < 0.05). The subjective estimation of the symptoms evaluated with the use of the Dizziness Handicap Inventory and the Visual Analogue Scale revealed a statistically significant improvement in both groups, yet it was higher in group 1., Conclusions: The compensation achieved after 6 weeks of the customized, supervised outpatient rehabilitation program in group 1 was superior to the results of the home-based unsupervised Cawthorne-Cooksey and balance exercises. Int J Occup Med Environ Health. 2020;33(3):273-82., (This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.)

Cultivated carrot and its wild ancestor co-occur in most temperate regions of the world and can easily hybridize. The genetic basis of the process of domestication in carrot is not well understood. Recent results of an investigation on genetic diversity structure of cultivated and wild carrot and signatures for domestication using Diversity Arrays Technology (DArT) allowed identification of polymorphisms differentiating wild and cultivated accessions. We selected one of these polymorphisms, showing the strongest evidence for directional selection in the course of domestication, and converted it into a co-dominant cleaved amplified polymorphic site (CAPS) marker named cult. To achieve that, we designed site-specific primers anchored in sequences flanking the original DArT clone, amplified and sequenced the PCR products derived from cultivated and wild carrot. A PstI restriction site present in the 'cultivated' variant and absent in the 'wild' was subsequently used for routine differentiation the two variants. We validated the cult marker on 88 accessions of cultivated and wild carrot, each represented by five individuals. The allelic variant associated with the wild phenotype was only rarely observed in cultivated carrot, mostly in purple-rooted accessions originating Turkey and Iran, possibly indicating that the physical association between the diagnostic polymorphism and the putative 'domestication gene' has been broken in a group of Eastern carrots.

Introduction: It is estimated that between XVI and XIX century one fourth of European population died of tuberculosis. Nowadays tuberculosis is still one of the most important infectious diseases. In 2009 estimately 9 million new cases were registered worldwide, mortality due tuberculosis reached 1.5 million. In Poland extrapulmonary tuberculosis is rare (7% of overall morbidity) and most commonly affects pleura, lymph nodes, bones, joints and genitourinary system. Head and neck tuberculosis is rare and causes many diagnostics problems., Methods: Retrospective analysis of case histories of patients admitted to ENT Department of Silesian Medical University in Katowice., Results: Between 1993 and 2010 four cases of head and neck tuberculosis were diagnosed in our Clinic. Two of patients were admitted to the hospital with symptoms of laryngeal tumor such as difficulty in swallowing. During direct laryngoscopy tissue specimens were taken. Examination of the third patient showed tumor located below left angle of mandibule. During superficial parotidectomy tumor was removed. In the fourth registered case tuberculosis manifested as tumor of nasopharynx. In every case which is mentioned above pathology reports revealed epithelioid cell granulomas with caseous necrosis typical for tuberculosis. Patients underwent tuberculostatic treatment., Conclusion: Rare occurrence and lack of characteristic symptoms of head and neck tuberculosis often lead to misdiagnosis. Histopathological examination is the most important diagnostic procedure. Microbiological examination is difficult in extrapulmonary tuberculosis, because of low concentration of pathogens in specimens. Tuberculostatic therapy is the leading method of treatment in every case of tuberculosis., (Copyright © 2011 Polish Otolaryngology Society. Published by Elsevier Urban & Partner (Poland). All rights reserved.)

Küttner's tumor is a benign tumour-like lesion of the salivary glands. Predominantly affects the submandibular gland. It is also known as chronic sclerosing sialoadenitis or cirrhosis of submandibular gland. This is an underrecognized entity in the surgical pathology and cytology literature. Most patients experience recurrent pain, discharge and swelling that is often associated with eating, but others only have asymptomatic hard swelling of the submandibular gland. Histologic examination of the excised submandibular glands revealed preserved lobular architecture, thickening of interlobular septa by sclerotic tissue, dense lymphoplasmacytic infiltrate, preservation of ducts with periductal fibrosis, and variable loss of acini. The morphologic appearance, in conjunction with the elevated IgG4 expression, distinguishes chronic sclerosing sialadenitis from other inflammatory diseases of the salivary glands. Chronic sclerosing sialadenitis belongs to the spectrum of IgG4-related diseases. We present a case of Küttner's tumor in a 62-year-old female treated by surgery. Although this disease was first described by Küttner in 1896, this clinical entity which masquerades as carcinoma is underdiagnosed by many surgeons. There is not enough evidence to support any diagnostic means that could help in the differential diagnosis of this benign condition. Given the high rate of malignancy in firm, painless lesions of the submandibular gland, surgical excision is often advocated and Küttner's tumor is usually diagnosed by the histopathologist., (Copyright © 2011 Polish Otolaryngology Society. Published by Elsevier Urban & Partner (Poland). All rights reserved.)