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The paper presents the microstructure, chemical and phase composition of thin scale, obtained as a result of high-temperature corrosion of X20Cr13 stainless steel. Samples were exposed to gas atmosphere of the following composition: 0.25 vol.% of SO2 and 99.75 vol.% of Ar at 600 °C for 5 h. As a consequence, thin compact scale was formed on steel surface. This scale consisted of three different zones. An amorphous zone was formed close to steel surface. Then, nanocrystalline zone could be observed. Finally, larger grains were formed during the corrosion process. The analysis of the chemical composition revealed higher concentration of chromium near steel surface. In contrast, to chromium, the content of iron, increased near the scale surface. It was found out that the (Cr, Mn, Fe)5O12 phase appeared in the thin scale.

The aim of the study was to evaluate the effect of processing variables on the porosity and fractography of Cr and Cr-Mo PM steels. The measurements were performed on sintered steels made from commercial Höganäs pre-alloyed powders: Astaloy CrA, Astaloy CrL and Astaloy CrM with two different carbon concentrations (0.2% and 0.6%) added in the form of ultra fine graphite powder grade C-UF. Following mixing in Turbula mixer for 30 minutes, green compacts were single-action pressed at 660 MPa according to PN-EN ISO 2740 standard. Sintering was carried out in a laboratory horizontal tube furnace at 1120°C and 1250°C for 60 minutes, in an atmosphere containing 5%H2 and 95%N2. After sintering, the samples were tempered at 200°C for 60 minutes in air. For porosity evaluation computer software was employed. Hitachi S-3500M SEM equipped with EDS (made by Noran) was employed for fracture analysis. The steel based on Astaloy CrM pre-alloyed powder is characterized by fine pores and good mechanical properties. When sintered at 1250°C, it had area of pores approx. 7.12 μm2, ultimate tensile strength (UTS) about 679 MPa and elongation about 4%. The steels were characterized by ductile/cleavage and ductile fractures.

The article presents the investigation results concerning the determination of the characteristics of erosive wear caused by the impact of Al2O3 solid particles on the surface of Inconel 625 alloy after plastic working and the same material after weld cladding process using the CMT method. Erosion wear tests were performed at two temperatures: 20°C and 650°C. The erosion tests were conducted using the standard ASTM G76. A jet with a specified abrasive waight was directed to the surface of the tested material at an α impingement angle varied in the range of 30-90° at a velocity imparted to the abrasive by the medium, which was compressed air. The eroded surface was examined using a scanning electron microscope (SEM), while the depths of craters caused by the erosion tests were measured with an optical profilometer. The predominant mechanisms of the formation of mass losses during solid particle erosion were microcutting and microfissuring.

Asthma is a chronic, inflammatory, heterogenic disease of the bronchi. It is characterised by bronchial obstruction in the form of wheezing, coughing, shortness of breath and breathing difficulty, showing variable intensity and resolving after medication, or sometimes spontaneously. Making the diagnosis of asthma in children under 5 years of age is based on clinical criteria – the presence of symptoms of bronchial constriction, confirmation of its reversibility and lack of symptoms suggestive of other clinical diagnosis. The criterion for diagnosis are usually three episodes of bronchial obstruction, or a single episode of severe intensity. A detailed history and physical examination allows in most cases to rule out other diseases with similar clinical course. Frequent recurrence of symptoms is an indication for the initial differential diagnosis in primary health care, including a chest X-ray, blood count, often an ENT and/or allergological consultation. However severe, frequent and not responding to treatment episodes of bronchoconstriction indicate the need for diagnostics in specialist hospital wards. Chronic treatment of asthma is based on the administration of anti-inflammatory drugs, inhaled therapy is the treatment of choice in most patients. The assessment of the severity of asthma exacerbation determines the range of treatment, on an outpatient basis consisting of bronchodilators, corticosteroids and oxygen therapy. An important element of treatment is appropriate patient education, with particular attention to the exacerbation risk factors and correct inhalation technique. Children suffering from asthma should be vaccinated against pneumococcal disease and against influenza annually.

The influence that general contractors and subcontractors have on the operation of a company is immense. Keeping this in mind, the authors have decided to develop and algorithm based on the analysis of partnering relations between construction companies that would select the best possible construction company for the purposes of cooperation. This algorithm, developed for a given construction company, is meant to support its decision-making system in the field of the selection of another construction company to cooperate with. The author has made references to earlier research, in which she had used the ELECTRE III method, and in which she bad analysed the possibility of applying the BIPOLAR method in order to solve the problem of the selection of a construction company to develop partnering relations with. The author provided an example of the calculations performed for a selection of construction companies.

The gut microbiota plays a pivotal role in the maintenance of human health. Numerous factors, including the mode of delivery, impact early gut colonization in newborns. Recent research focuses on the use of probiotics in the prevention of gut dysbiosis in newborns delivered by cesarean section (CS). The objective of this study was to determine whether a probiotic supplement given to newborns delivered by CS during their stay in the maternity ward alters the pattern of early gut colonization by lactic acid bacteria versus potential pathogens. A prospective, randomized trial was conducted. In total, 150 newborns, born at 38–40 weeks gestational age and delivered by CS, were included in the study. They were randomized into the intervention group, supplemented orally with a probiotic containing Bifidobacterium breve PB04 and Lactobacillus rhamnosus KL53A, and the control group. Stool samples were obtained on days 5 and 6 of life and after one month of life and were analyzed for the presence and abundance of the main groups of bacteria. An application of two probiotic bacteria during the first days of life after CS resulted in quick and abundant colonization by days 5 and 6, with high populations of L. rhamnosus and B. breve. The applied bacterial strains were present in the majority of neonates one month after. The supplementation of term neonates delivered by cesarean section immediately after birth with a mixture of L. rhamnosus and B. breve enriched the gut microbiota composition with lactic acid bacteria.

This paper presents a proposal for a historic building thermal diagnostics algorithm for the example of a historical townhouse located in Lviv, Ukraine. The authors proposed a testing and diagnostics procedure that should precede design and renovation work associated with improving the energy standard of the buildings under discussion. The procedure was presented using a case study of a selected historical building. The scope of the study included an assessment of the building’s technical condition, thermal vision diagnostics, wall moisture, and water absorption in the context of protection against rain. Sample thermal and hygrothermal calculations were performed for a sample architecture element. The calculations included simulations of partition envelope behaviour after planned thermal retrofitting had been carried out. Performing the presented thermal diagnostics methods in three interlinked blocks (A, B, and C) shall ensure the proper thermal retrofitting of historical buildings in the context of their further occupancy.

Caries are a pathological process of extracorporeal nature, characterized by demineralization of inorganic substances as well as proteolysis triggered by acids produced by bacteria present in dental plaque, as a result of metabolism of sugars of both external and internal origin. Periodontal disease, on the other hand, is a multifactorial degenerative disease associated with inflammation, involving a group of tissues that surround the dental cervix and root of the tooth. It is believed that one of the mechanisms in the etiopathogenesis of caries and periodontitis are disorders of local and/or general oxidative stress (OS) parameters. Numerous clinical studies have confirmed the relationship between oxidative stress markers and oral diseases. In most analyzed studies, technical and biological variability was so high that none of the markers so far has proven suitable for routine clinical use. The aim of systematic reviews of the literature is to present the existing studies on OS parameters, mainly concerning the activity of antioxidant enzymes in saliva of patients with caries and periodontitis.

The paper discusses thermal quality improvement in historic buildings. It is based on a case study of a wooden historical building in an architectural style typical of Zakopane, located in the Podhale region of Poland. The building’s historical value and timber structure prevent the application of typical thermal retrofitting solutions. This paper presents an analysis of the possibilities of the improvement of energy performance of a historic building (villa) which included: a review of the available energy performance improvement solutions applicable to this type of building, with a particular focus on applying internal insulation; a technical condition assessment using non-invasive methods, the identification of problematic areas in terms of the thermal retrofitting of buildings with timber walls and decks; in situ tests: thermovision tests which showed the places with temperature distribution field disturbances in the building’s envelope, focusing on thermal bridges; measurements of actual thermal transmittance coefficients for extant partitions; measurements of the building’s airtightness and the microclimate in selected rooms; numerical analysis: an assessment of the influence of the thermal bridges on the building’s existing condition, an analysis of water content changes in wall systems post-insulation. The presented approach enables the improvement of the energy performance of timber historical buildings while preserving the historical value of its architecture. It is innovative because it tries to fill in a research gap concerning a lack of relevant guidelines in Poland. The research questions that the authors asked were as follows. Is it possible to improve the thermal insulation of a building’s wooden walls without adversely affecting the building’s technical condition? With regard to the necessity to meet nZEB (nearly zero energy building) standards, is it feasible to improve the timber walls of historical buildings? The study found that under the correct assumptions and while maintaining a responsible approach to design, it is possible to improve the energy performance of historical buildings without interfering with historical heritage.

Adapting historic buildings to new, modern forms generates not only financial benefits for developers but can also allow them to survive for future generations through proper remodelling. The variety of decision criteria related to the selection of a new function of a historic building makes this problem multidimensional. Many of these criteria are interrelated and have a non-linear nature which requires a comprehensive network-based rather than a classic hierarchical approach to conducting multi-criteria analysis. A comprehensive approach taking into account the specificity of the analysed problem was proposed. The study was supported by an example of the choice of building function as part of the adaptive reuse of a historic building located in Zakopane. The following variants have been analysed: a hostel (existing state), a five-star hotel, a folk art gallery and a conference and training centre. The final rating of alternatives indicates that the hotel best meets the adopted decision criteria.

This paper reports the characterization of iron oxide magnetic nanoparticles obtained via the thermal decomposition of an organometallic precursor, which were then loaded into nanocapsules prepared via the emulsification process in the presence of an amphiphilic derivative of chitosan. The applied synthetic method led to the formation of a hydrophobic layer on the surface of nanoparticles that enabled their loading in the hydrophobic liquid inside of the polymer-based capsules. The average diameter of nanoparticles was determined to be equal to 15 nm, and they were thoroughly characterized using X-ray diffraction (XRD), magnetometry, and Mössbauer spectroscopy. A core−shell structure consisting of a wüstite core and maghemite-like shell was revealed, resulting in an exchange bias effect and a considerable magnetocrystalline anisotropy at low temperatures and a superparamagnetic behavior at room temperature. Importantly, superparamagnetic behavior was observed for the aqueous dispersion of the nanocapsules loaded with the superparamagnetic nanoparticles, and the dispersion was shown to be very stable (at least 48 weeks). The results were analyzed and discussed with respect to the potential future applications of these nanoparticles and nanocapsules based on biopolymers as platforms designed for the magnetically navigated transport of encapsulated hydrophobic substances.

The Directive 2010/31/EU on the energy performance of buildings has introduced the standard of “nearly zero-energy buildings” (NZEBs). European requirements place the obligation to reduce energy consumption on all European Union Member States, particularly in sectors with significant energy consumption indicators. Construction is one such sector, as it is responsible for around 40% of overall energy consumption. Apart from a building’s mass and its material and installation solutions, its energy consumption is also affected by its placement relative to other buildings. A proper urban layout can also lead to a reduction in project development and occupancy costs. The goal of this article is to present a method of optimising single-family house complexes that takes elements such as direct construction costs, construction site organisation, urban layout and occupancy costs into consideration in the context of sustainability. Its authors have analysed different proposals of the placement of 40 NZEBs relative to each other and have carried out a multi-criteria analysis of the complex, determining optimal solutions that are compliant with the precepts of sustainability. The results indicated that the layout composed of semi-detached houses scored the highest among the proposed layouts under the parameter weights set by the developer. This layout also scored the highest when parameter weights were uniformly distributed during a test simulation.

Juvenile dermatomyositis (JDM) is a rare form of childhood autoimmune myositis that presents with proximal muscle weakness and skin rash. B cells are strongly implicated in the pathogenesis of the disease, but the underlying mechanisms are unknown. Therefore, the main objective of our study was to investigate mechanisms driving B cell lymphocytosis and define pathological features of B cells in JDM patients. Patients were recruited through the UK JDM Cohort and Biomarker study. Peripheral blood B cell subpopulations were immunophenotyped by flow cytometry. The results identified that immature transitional B cells were significantly expanded in active JDM, actively dividing, and correlated positively with disease activity. Protein and RNAseq analysis revealed high interferon alpha (IFNα) and TLR7-pathway signatures pre-treatment. Stimulation of B cells through TLR7/8 promoted both IL-10 and IL-6 production in controls but failed to induce IL-10 in JDM patient cells. Interrogation of the CD40–CD40L pathway (known to induce B cell IL-10 and IL-6) revealed similar expression of IL-10 and IL-6 in B cells cultured with CD40L from both JDM patients and controls. In conclusion, JDM patients with active disease have a significantly expanded immature transitional B cell population which correlated with the type I IFN signature. Activation through TLR7 and IFNα may drive the expansion of immature transitional B cells in JDM and skew the cells toward a pro-inflammatory phenotype.

The paper presents results of the microstructure investigation, changes of chemical composition and hardness of the 7CrMoVTiB10-10 steel joints and their analyzes after heat treatment at 755 °C for 0.5 h, 1 h, 2 h. The joints were performed with a CO2 laser. Microstructural research where carried out using light and scanning electron microscopy. The energy dispersive spectroscopy was applied to specify distribution of chemical elements in the welded joints and revealed precipitates. Moreover the hardness tests were determined in order to define change of hardness at the cross-section of the joints. Investigation shown homogenous chemical composition in the welds. In the joints the precipitates rich in Ti, Mn, and V were revealed. Hardness of the weld amounted 400 HV1, but of HAZ – 360 HV1. Heat treatment led to decreasing of the hardness of laser joints to about 270 HV1.

The article presents the use of the Mamdani fuzzy reasoning model to develop a proposal of a system controlling partnering relations in construction projects. The system input variables include: current assessments of particular partnering relation parameters, the weights of these parameters' impact on time, cost, quality and safety of implementation of construction projects, as well as the importance of these project assessment criteria for its manager. For each of the partnering relation parameters, the project’s manager will receive control recommendations. Moreover, the parameter to be improved first will be indicated. The article contains a calculation example of the system's operations.

In this work the pulsed laser deposition (PLD) and the pulsed electron beam deposition (PED) techniques were used for fabrication of Mo-Bi2O3, La1−xSrxCoO3, La1−xCaxCoO3 and Al-Mg thin films. An influence of ablation process basic parameters on the coatings structure and properties was discussed. Two types of laser ablation systems were applied: one equipped with a KrF excimer and second with a Q-switched Nd:YAG. Films were deposited on Si and MgO substrates. Scanning (SEM) and transmission (TEM) electron microscopy, atomic force microscopy (AFM) as well as X-ray diffraction (XRD) were used for structural analysis. Investigations focused on structure and chemical composition showed that smooth and dense thin films with nanocrystalline structure, preserving the composition of the bulk target, could be obtained by the both PLD and PED techniques. Research study showed that by a proper selection of PLD and PED process parameters it was possible to deposit films with significantly decreased amount and size of undesirably nanoparticulates.

Celem artykułu jest przedstawienie aktualnych badań dotyczących roli wskaźników prognostycznych EEG i QEEG (ilościowa elektroencefalografia) w przewidywaniu rezultatów leczenia przeciwdepresyjnego. Depresja należy do najczęstszych zaburzeń psychicznych; rozpowszechnienie w populacji to 7–25% w ciągu całego życia. Wybór leku przeciwdepresyjnego opiera się na metodzie prób i błędów, co często wiąże się z niepowodzeniami. Konieczne są dalsze badania zmierzające do ustalenia obiektywnych biomarkerów oraz ich kombinacji w celu przyspieszenia leczenia depresji i zwiększenia jego skuteczności. W badaniach z zastosowaniem QEEG różnice w pomiarach przed leczeniem korelowały z późniejszą poprawą kliniczną. W szczególności istotne klinicznie wydają się następujące zależności: niższa moc theta przed włączeniem leczenia, spadek wskaźnika kordancji theta w czasie od 48 godzin do 2 tygodni po rozpoczęciu farmakoterapii, wzrost mocy alfa, wzrost mocy theta nad zakrętem obręczy, większa moc alfa nad prawą półkulą. Z kolei wzrost mocy theta i delta wiąże się ze słabą odpowiedzią na leczenie przeciwdepresyjne.

The present paper uses the developed model of the influence of partnering relations on the time, cost, quality and safety of implementation of construction projects. On its basis, a questionnaire has been created and a preliminary survey has been conducted. The paper presents an analysis of correlations between the level of partnering relations in the context of the partnering measures indicated in the model and their influence on the time, cost, quality and safety of implementation of construction projects. The analysis was conducted based on the data collected in 52 construction projects. The values of the Spearman rank correlation coefficient and the Pearson product-moment correlation coefficient have been calculated for the examined relations. The analysis allowed for indicating the measures of partnering whose improvement most often brings benefits with regard to the time, cost, quality and safety of implementation of construction projects. Among the 80 analysed correlations, the ones identified as strong were: 15 relations connected with the time, 8 with the cost, 5 with the quality and 1 with the safety of implementation of construction projects.

The directions of development of the construction market are not only related to the need to own one’s own home but also to increasing functional and economic requirements and conditions of sustainable development. The perception and understanding of prefabrication in housing construction are undoubtedly starting to change. Sustainable construction criteria may constitute a significant turning point and support for the development of new prefabricated housing construction technologies. Entrepreneurs are slowly perceiving an opportunity for the development of prefabrication in the construction market. The implementation and popularisation of ready-made homes will undoubtedly constitute a favourable change in the Polish construction market; however, this will require a modification of habits. This article presents an historical analysis of the development of the prefabricated housing construction market as well as an attempt to answer questions concerning the future of prefabrication in housing construction in Poland based on the conducted studies.