Repozytorium Uniwersytetu Śląskiego RE-BUŚ
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Twelve-Month Evaluation of Temperature Effects of Radiotherapy in Patients after Mastectomy
Get PDFThe aim of this study was to verify the changes in the temperature distribution within the
breast at twelve months after the end of radiotherapy for breast cancer. The study included twentyfour
women. The first test group consisted of twelve women who underwent breast mastectomy
and qualified for radiotherapy according to standard medical treatment procedures. The second
group included twelve healthy women. The tests were conducted before treatment with radiation
therapy and two months, six months, nine months, and one year after the end of treatment. The
mean temperature values changed depending on the time that had elapsed since the end of
treatment. The highest temperature increase in all patients was observed six months after the end
of radiotherapy. This research has confirmed that the assessment of temperature changes in the
breast area after radiotherapy can evaluate the severity and lesions in the time course of the
radiation reaction
The Thickness of Talus Deposits in the Periglacial Area of SW Spitsbergen (Fugleberget Mountainside) in the Light of Slope Development Theories
Get PDFPeriglacial slopes are susceptible to recent climate change. The rate of morphogenetic processes depends on numerous factors. The most important of these is the warming of the air and ground, increased precipitation (extreme rainfall in particular), and the rate of snow cover decay. The dynamics of these processes may effectively modify contemporary slope development models. The paper shows the structure of selected talus slopes on a Fugleberget mountainside, based on field observations and radar (GPR) soundings. The results are then compared to classical slope models. The radar survey in April and May 2014 used a RAMAC CU II Malå GeoScience system equipped with a 30 MHz RTA antenna (Rough Terrain Antenna). Five GPR profiles of different lengths were obtained along the talus axes, transversally on Fugleberget and partly on the Hansbreen lateral moraine. According to the radar soundings, the maximum thickness of the debris deposits is 25–30 m. The thickness of the weathered material increases towards the talus cone’s terminal part, and debris deposits overlap marine sediments. The talus slopes’ morphometry shows that their current forms differ from standard slope models, which may be due to the significant acceleration of geomorphic processes resulting from climate change, including rapid warming in the last four decades
Tuning Physical Properties of NiFe2O4 and NiFe2O4@SiO2 Nanoferrites by Thermal Treatment
Get PDFThe comparison between NiFe2O4 (co-precipitation) and NiFe2O4@SiO2 (co-precipitation and
microemulsion) ferrite nanoparticles in their as-received and annealed form is presented. The
structural characterization revealed the gradual crystallization of as-received samples induced
by thermal treatment. The existence of cubic inverse spinel ferrite structure with tetrahedral and
octahedral iron occupancy is confirmed in all samples by the comprehensive study. The Fouriertransform
infrared (FTIR) spectroscopy confirmed the typical spinel structure and other Febased
states, whereas the presence of nonstoichiometric hematite is detected in the annealed
NiFe2O4 sample. In the case of nanoparticles embedded into the silica matrix, the crystallization
of initially amorphous silica is revealed in structural and microstructural characterization. As
shown by FTIR, the applied thermal treatment reduces the water molecules and hydroxyl units
compared to the initial material. The separation of the rhombohedral hematite α-Fe2O3 phase in
the NiFe2O4 ferrite evidenced during the annealing process is demonstrated in structural and
magnetic studies. The analysis of saturation magnetization pointed to the spin canting phenomenon
in the surface layer with a slight change of the so-called dead layer upon heating. The
room temperature superparamagnetic state (SPM) is modified in the NiFe2O4 sample across
annealing as an effect of ferrite crystallization and grain growth as well as hematite separation.
For as-received NiFe2O4, with temperature decrease, the blocking process preceded by the
freezing process is observed. The silica shell is recognized as the sustaining cover for the SPM
state. The electronic structure studies confirmed the complex nature of the Fe-based states
Multifunctional Silver(I) Complexes with Metronidazole Drug Reveal Antimicrobial Properties and Antitumor Activity against Human Hepatoma and Colorectal Adenocarcinoma Cells
Get PDFSilver salts and azole derivatives are well known for their antimicrobial properties. Recent evidence has demonstrated also their cytotoxic and genotoxic potential toward both normal and cancer cells. Still, little is known about the action of complexes of azoles with silver(I) salts. Thus, the goal of the study was to compare the chemical, cytotoxic and antimicrobial properties of metronidazole complexes with silver(I) nitrate and silver(I) sulfate to metronidazole and pure silver(I) salts. We synthetized a novel complex, [Ag(MTZ)2]2SO4, and confirmed its chemical structure and properties using 1H and 13C NMR spectroscopy and X-Ray, IR and elemental analysis. To establish the stability of complexes [Ag(MTZ)2NO3] and [Ag(MTZ)2]2SO4, they were exposed to daylight and UV-A rays and were visually assessed. Their cytotoxicity toward human cancer cells (HepG2, Caco-2) and mice normal fibroblasts (Balb/c 3T3 clone A31) was determined by MTT, NRU, TPC and LDH assays. The micro-dilution broth method was used to evaluate their antimicrobial properties against Gram-positive and Gram-negative bacteria. A biofilm eradication study was also performed using the crystal violet method and confocal laser scanning microscopy. The photo-stability of the complexes was higher than silver(I) salts. In human cancer cells, [Ag(MTZ)2]2SO4 was more cytotoxic than Ag2SO4 and, in turn, AgNO3 was more cytotoxic than [Ag(MTZ)2NO3]. For Balb/c 3T3 cells, Ag2SO4 was more cytotoxic than [Ag(MTZ)2]2SO4, while the cytotoxicity of AgNO3 and [Ag(MTZ)2NO3] was similar. Metronidazole in the tested concentration range was non-cytotoxic for both normal and cancer cells. The complexes showed increased bioactivity against aerobic and facultative anaerobic bacteria when compared to metronidazole. For the majority of the tested bacterial strains, the silver(I) salts and complexes showed a higher antibacterial activity than MTZ; however, some bacterial strains presented the reverse effect. Our results showed that silver(I) complexes present higher photo-stability, cytotoxicity and antimicrobial activity in comparison to MTZ and, to a certain extent, to silver(I) salts
Can insecticide-free clean water regenerate the midgut epithelium of the freshwater shrimp after dimethoate treatment?
Get PDFInsecticides such as dimethoate persist for a long time in freshwater environments, influencing the physiology of
the animals inhabiting such environments. In aquatic organisms, toxic substances can enter the body through the
epidermis and the digestive system. The midgut is part of this system in which intense processes constitute a
barrier against the effects of toxic substances on the body. The aim of this study was to evaluate the toxic potential
of dimethoate in the midgut epithelium of the freshwater shrimp Neocaridina davidi, emphasizing ultrastructural
alterations. However, the additional and main purpose was to determine whether the midgut
epithelium can regenerate after placing animals in insecticide-free clean water after various periods of exposure
to dimethoate. N. davidi originates from Asia, but it has also been described in European rivers. This species is of
particular interest among breeders worldwide due to its ease of breeding and reproduction. The animals were
treated with dimethoate for 1, 2, and 3 weeks and then placed in clean water for 1, 2, and 3 weeks. The qualitative
and quantitative analysis revealed different sensitivity of organs forming the midgut in freshwater
crustaceans and the possibility for midgut regeneration after insecticide exposure. We concluded that different
processes were triggered in the intestine and hepatopancreas to regenerate cells after damage, and mitochondria
were the first organelles to respond to the appearance of a stressor in the living environment
Unraveling the hidden paleobiodiversity of the Middle Devonian (Emsian) crinoids (Crinoidea, Echinodermata) from Poland
Get PDFMost previous publications on Devonian crinoids from the Holy Cross Mountains in Poland have concentrated on crinoid columns, and until now, little has been published about crinoid cups and calyxes. Herein, five crinoid taxa are described from an abundant occurrence of aboral cups and partial crowns from the Bukowa Góra Member (Emsian) in the Holy Cross Mountains of southern Poland. The following taxa are described: Bactrocrinites sp., Codiacrinus sevastopuloi sp. nov., Halocrinites geminatus (Bohatý, 2005), Halocrinites schlotheimii Steininger, 1831, and a single brachial plate from a flexible crinoid placed in Flexibilia incertae sedis. Simple discoid holdfasts are also present encrusted to cylindrical stromatoporoids. These taxa are the first crinoids described from the remains of partial crowns from Emsian strata of Poland
Digital media and political consumerism in the United States, United Kingdom, and France
Get PDFDigital media use can connect citizens across geographic boundaries into coordinated action by distributing political information, enabling the formation of groups, and facilitating political talk. These activities can lead to political consumerism, which is an important and popular form of political participation that translates across geographic borders. This article uses original survey data ( n = 9284) to examine the relationship between digital media use and political consumerism in the United States, United Kingdom, and France. Talking politics online, joining social groups on social media, and searching online for political information increase participation in political consumerism. However, the strength of these positive correlations differs by age, country, and mode of political consumerism. Joining social groups on social media has a much larger effect size on buycotting compared to boycotting. The findings imply that social groups are more salient in the mobilization process for buycotting campaigns compared to boycotting campaigns
Kursy typu MOOC na polskiej platformie edukacyjnej Navoica - perspektywa twórców
Get PDFCEL NAUKOWY: Celem artykułu jest przedstawienie standardów tworzenia kursów typu MOOC
na platformie edukacyjnej Navoica, a także opisanie procedury uruchamiania tych kursów w języku
polskim i angielskim oraz wyeksponowanie roli profesjonalistów (m.in. uniwersytetów) w upowszechnianiu
aktualnych treści naukowych w sposób odpowiadający preferencjom cyfrowych odbiorców.
PROBLEM I METODY BADAWCZE: Realizacja wskazanych zadań była możliwa dzięki jakościowej
analizie danych zastanych, tzw. analizie treści, obejmującej dokumenty, wywiady i literaturę
poświęconą wyzwaniom stawianym edukacji XXI wieku. Artykuł zawiera także charakterystykę warsztatu
– platformy edukacyjnej Navoica, która służy do generowania i realizacji kursów zdalnych.
PROCES WYWODU: Wywód obejmuje: uzasadnienie podjęcia tematu (zob. Wstęp); analizę wybranych
treści opublikowanych w dokumencie Navoica. Polska platforma edukacyjna oferująca kursy
typu MOOC. Wytyczne dla twórców kursów; opis wdrażania tych standardów na przykładzie dwóch
kursów typu MOOC (zob. m.in. podrozdział Warsztat autora kursu typu MOOC); refleksje wynikające
z doświadczeń autora kursu typu MOOC (zob. podrozdział Perspektywa autora kursu typu MOOC);
a także odniesienia do kształcenia zdalnego w sytuacji globalnej pandemii (zob. Odbiorcy kursów
typu MOOC, Kursy typu MOOC a realia edukacyjne w czasie globalnej pandemii – podsumowanie).
WYNIKI ANALIZY NAUKOWEJ: Czas globalnej pandemii wykazał, że powszechny dostęp do
kursów, szkoleń czy webinarów zwiększa szanse edukacyjne przedstawicieli różnych pokoleń. Nie
istnieją ograniczenia geograficzne, wiekowe, zawodowe czy inne dla potencjalnych uczestników
kursów, w tym – dla osób z niepełnosprawnościami. Natomiast dostępność kursów w globalnym
języku angielskim znosi także barierę językową i komunikacyjną.
WNIOSKI, INNOWACJE, REKOMENDACJE: Idea tworzenia kursów typu MOOC jest warta
upowszechniania, ponieważ dostęp do aktualnych treści naukowo-badawczych w sposób, który odpowiada wymaganiom i preferencjom zwłaszcza pokoleń Y i Z, jest szczególnie ważny w czasach
postpandemicznych
Application and Multi-Stage Optimization of Daylight Polymer 3D Printing of Personalized Medicine Products
Get PDFAdditive technologies have undoubtedly become one of the most intensively developing
manufacturing methods in recent years. Among the numerous applications, the interest in 3D
printing also includes its application in pharmacy for production of small batches of personalized
drugs. For this reason, we conducted multi-stage pre-formulation studies to optimize the process of
manufacturing solid dosage forms by photopolymerization with visible light. Based on tests planned
and executed according to the design of the experiment (DoE), we selected the optimal quantitative
composition of photocurable resin made of PEG 400, PEGDA MW 575, water, and riboflavin, a
non-toxic photoinitiator. In subsequent stages, we adjusted the printer set-up and process parameters.
Moreover, we assessed the influence of the co-initiators ascorbic acid or triethanolamine on the
resin’s polymerization process. Next, based on an optimized formulation, we printed and analyzed
drug-loaded tablets containing mebeverine hydrochloride, characterized by a gradual release of
active pharmaceutical ingredient (API), reaching 80% after 6 h. We proved the possibility of reusing
the drug-loaded resin that was not hardened during printing and determined the linear correlation
between the volume of the designed tablets and the amount of API, confirming the possibility of
printing personalized modified-release tablets
An effective similarity measurement under epistemic uncertainty
Get PDFThe epistemic uncertainty stems from the lack of knowledge and it can be reduced when the knowledge increases. Such inter-pretation works well with data represented as a set of possible states and therefore, multivalued similarity measures. Unfortunately, set-valued extensions of similarity measures are not computationally feasible even when the data is finite. Measures with properties that allow efficient calculation of their extensions, need to be found. Analysis of various similarity measures indicated logic-based (additive) measures as an excellent candidate. Their unique properties are discussed and efficient algorithms for computing set-valued extensions are given. The work presents results related to various classes of fuzzy set families: general ones, intervals of fuzzy sets, and their finite sums. The first case is related to the concept of the Fuzzy Membership Function Family, the second corresponds to the Interval-Valued Fuzzy Sets, while the third class is equivalent to the concept of Typical Interval-Valued Hesitant Fuzzy Sets