ANALIZA JAKOŚCI WYDRUKOWANYCH PRÓBEK PLA PRZY UŻYCIU RÓŻNYCH DRUKAREK 3D I PROGRAMÓW DO PRZYGOTOWANIA WYDRUKU

The article presents the impact of individual settings of both 3D printers and software dedicated to the preparation of printouts. 3D printing methods are discussed. The individual methods and tools necessary for the implementation of 3D prints are described. Materials that are used in 3D printing technology are also discussed. In addition, the construction of printers on which the samples for the tests described in this work were prepared was discussed. The advantages and disadvantages of using individual slicers for 3D printing are presented. The obtained measurement results of samples made of polylactide (PLA) are presented. The work was summarized with final conclusions.W artykule przedstawiono wpływ poszczególnych ustawień zarówno drukarek 3D oraz oprogramowania dedykowanego do przygotowania wydruków. Omówiono metody druku 3D. Opisano poszczególne metody i narzędzia niezbędne do realizacji wydruków 3D. Omówiono także materiały, które są wykorzystywane w technologii druku 3D. Ponadto omówiono budowę drukarek, na których zostały przygotowane próbki do badań opisanych w tejże pracy. Przedstawiono wady i zalety korzystania z poszczególnych slicerów do druku 3D. Zaprezentowano otrzymane wyniki pomiarowe próbek wykonanych z polilaktydu (PLA). Pracę podsumowano wnioskami końcowymi

Taxonomic and chemical assessment of exceptionally abundant rock mine biofilm

Background An exceptionally thick biofilm covers walls of ancient gold and arsenic Złoty Stok mine (Poland) in the apparent absence of organic sources of energy. Methods and Results We have characterized this microbial community using culture-dependent and independent methods. We sequenced amplicons of the 16S rRNA gene obtained using generic primers and additional primers targeted at Archaea and Actinobacteria separately. Also, we have cultured numerous isolates from the biofilm on different media under aerobic and anaerobic conditions. We discovered very high biodiversity, and no single taxonomic group was dominant. The majority of almost 4,000 OTUs were classified above genus level indicating presence of novel species. Elemental analysis, performed using SEM-EDS and X-ray, of biofilm samples showed that carbon, sulphur and oxygen were not evenly distributed in the biofilm and that their presence is highly correlated. However, the distribution of arsenic and iron was more flat, and numerous intrusions of elemental silver and platinum were noted, indicating that microorganisms play a key role in releasing these elements from the rock. Conclusions Altogether, the picture obtained throughout this study shows a very rich, complex and interdependent system of rock biofilm. The chemical heterogeneity of biofilm is a likely explanation as to why this oligotrophic environment is capable of supporting such high microbial diversity

Elements of crisis e-learning : perspectives of Polish teachers

The aim of the research was to investigate teachers' perspectives on the elements of emergency e-learning during the COVID-19 pandemic. The research was conducted with 134 teachers from different types of schools in Poland during the first wave of crisis e-learning (March - May 2020). The variables included in the analysis comprise teachers' use of differentiated teaching methods, student collaboration, school support for modern ICT, and teachers' digital competence. The findings are summarized as follows: (1) about a third of students did not develop the ability to work together in emergency e-learning; (2) more than two-thirds of teachers underlined that their schools actively promoted the idea of implementing ICT in education; (3) more than two-thirds of teachers emphasized that their school principals had systematically modernized the IT facilities necessary for effective teaching; (4) approximately half of the teachers were supported by the school authorities in strengthening their digital competence; and (5) teachers used various teaching methods in emergency e-learning, and the most popular methods were videos, presentations, e-learning platforms, and interactive games and applications; (6) teachers who did not differentiate digital teaching methods did not believe in the development of opportunities for soft skills among students; (7) the schools invested in technological facilities and supported the development of digital competence among teachers; and (8) the intensive use of e-learning platforms by teachers increased their positive attitude towards the development of soft competences (e.g., collaboration skills) among students

ANALYSIS OF THE QUALITY OF PRINTED PLA SAMPLES USING VARIOUS 3D PRINTERS AND PRINT PREPARATION PROGRAMS

The article presents the impact of individual settings of both 3D printers and software dedicated to the preparation of printouts. 3D printing methods are discussed. The individual methods and tools necessary for the implementation of 3D prints are described. Materials that are used in 3D printing technology are also discussed. In addition, the construction of printers on which the samples for the tests described in this work were prepared was discussed. The advantages and disadvantages of using individual slicers for 3D printing are presented. The obtained measurement results of samples made of polylactide (PLA) are presented. The work was summarized with final conclusions

Unprecedented Water Effect as a Key Element in Salicyl-Glycine Schiff Base Synthesis

Salens, as chelating, double Schiff base ligands, are an important group utilized in transition metal catalysis. They have been used to build interesting functional metal-organic frameworks (MOFs). However, salens interacting with amino acids have also found applications in receptors. Here, we intended to form a “green” glycine-derived salen fragment, but the available literature data were contradictory. Therefore, we optimized the synthetic conditions and obtained the desired product as two different crystallographic polymorphs (orthorhombic Pcca and monoclinic P21/c space groups). Their structures differ in conformation at the glycine moiety, and the monoclinic form contains additional, disordered water molecules. Despite the high stability of Schiff bases, these newly obtained compounds hydrolyze in aqueous media, the process being accelerated by metal cations. These studies, accompanied by mechanistic considerations and solid-state moisture and thermal analysis, clarify the structure and behavior of this amino acid Schiff base and shed new light on the role of water in its stability

Ocena stanu odżywienia u pacjentów z nadciśnieniem tętniczym w zależności od stopnia uszkodzenia mięśnia sercowego

Introduction. Hypertension is the most frequently diagnosed chronic disease in Poland. It may be asymptomatic in years. However, over time affects the most important organs. Among many complications is damage to the myocardium. In addition to pharmacological treatment, proper diet and lifestyle modification are the basis for therapy. The aim of the study was to assess the nutritional status of patients with hypertension depending on the level of myocardial damage. Material and methods. The study involved 33 patients aged 35–70 years with diagnosed hypertension and normal ejection fraction of the heart. In all subjects, the body composition was analyzed using the bioelectrical impedance method, echocard iography and NT-proBNP measurement. Results. Analyzing the left ventricle mass for the entire study group, a positive correlation was found with body weight (r = 0.5125, p = 0.0023), muscle mass (r = 0.5395, p = 0.0012), adipose tissue mass (r = 0.4488, p = 0.0088), body mass index (r = 0.3913, p = 0.0243), total water volume (r = 0.5273, p = 0.0016), lean body mass (r = 0.5375, p = 0.0013), protein (r = 0.5328, p = 0.0014), waist circumference (r = 0.5282, p = 0.0055), waist-to-hip ratio (r = 0.4914; p = 0.0043). The thickness of the intraventricular septum correlates positively with the duration of hypertension (r = 0.6979, p = 0.0248). The composition of the body of patients with hypertension correlates with the level of damage to the left ventricle. Weight reduction in obese or overweight people can have a positive effect on the condition of the heart muscle. Conclusions. It is necessary to educate patients about the proper diet and lifestyle changes. It is advisable to cooperate with a dietician. The inclusion of the body composition analysis in the diagnostics may improve the prognosis of the patients and motivate them to take an active part in the therapy.WSTĘP: Nadciśnienie tętnicze jest najczęściej diagnozowaną chorobą przewlekłą w Polsce. Latami może przebiegać bezobjawowo. Zaniedbanie leczenia może prowadzić do wielu powikłań, a wśród nich do uszkodzenia mięśnia sercowego. Obok leczenia farmakologicznego, odpowiednia dieta i modyfikacja stylu życia są podstawą terapii. Celem badania była ocena stanu odżywienia u pacjentów z nadciśnieniem tętniczym w zależności od stopnia uszkodzenia mięśnia sercowego. MATERIAŁ I METODY: W badaniu wzięło udział 33 pacjentów w wieku 35–70 lat, ze zdiagnozowanym nadciśnieniem tętniczym i prawidłową frakcją wyrzutową serca. U wszystkich badanych wykonano analizę składu ciała metodą impedancji bioelektrycznej, badanie echokardiograficzne oraz pomiar NT-proBNP. WYNIKI: Analizując masę lewej komory dla całej grupy badanej, wykazano dodatnią korelację z masą ciała (r = 0,5125; p = 0,0023), masą mięśniową (r = 0,5395; p = 0,0012), masą tkanki tłuszczowej (r = 0,4488; p = 0,0088), indeksem masy ciała (r = 0,3913; p = 0,0243), całkowitą objętością wody (r = 0,5273; p = 0,0016), beztłuszczową masą ciała (r = 0,5375; p = 0,0013), białkiem (r = 0,5328; p = 0,0014), obwodem talii (r = 0,5282; p = 0,0055), wskaźnikiem talia–biodro (r = 0,4914; p = 0,0043). Grubość przegrody międzykomorowej koreluje dodatnio z czasem trwania nadciśnienia (r = 0,6979; p = 0,0248). Kompozycja składu ciała pacjentów z nadciśnieniem tętniczym koreluje ze stopniem uszkodzenia lewej komory serca. Redukcja masy ciała u osób otyłych lub z nadwagą może mieć pozytywny wpływ na stan mięśnia sercowego. WNIOSKI: Niezbędne jest edukowanie pacjentów w zakresie prawidłowej diety i zmian stylu życia. Wskazana jest współpraca lekarza z dietetykiem. Włączenie do diagnostyki badania analizy składu ciała może poprawić rokowanie chorych oraz stanowić dla nich motywację do brania czynnego udziału w terapii

Research Concerning Electro magnetic Emissions from Residential On-grid PV Systems, Journal of Telecommunications and Information Technology, 2021, nr 4

The paper presents the results of grid power quality tests and wide frequency electromagnetic radiation level tests to which home power networks with photovoltaic systems have been subjected. The said results are meaningful from the point of view of safety and compatibility of electrical devices and the power supply system they are connected to. The tests covered stability of phase voltage and its frequency, harmonic level flicker, as well as RF radiated and emission levels. The measurements performed provide an answer to the question concerning the level of compliance of randomly selected home-installed PV systems with applicable recommendations and regulations concerning electromagnetic compatibility. The ability to meet the applicable standards translates into the health and safety of building inhabitants, which is the ultimate goal. Legal regulations concerning electromagnetic compatibility of renewable energy sources are consistent throughout the entire European Unio

Aktywizacja, rozwój, integracja: ku niezależnej starości

Praca recenzowana / peer-reviewed pape