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Purpose The purpose of this paper is to investigate the effect of remelting each layer on the homogeneity of nickel-titanium (NiTi) parts fabricated from elemental nickel and titanium powders using laser powder bed fusion (LPBF). In addition, the influence of manufacturing parameters and different melting strategies, including multiple cycles of remelting, on printability and macro defects, such as pore and crack formation, have been investigated. Design/methodology/approach An LPBF process was used to manufacture NiTi alloy from elementally blended powders and was evaluated with the use of a remelting scanning strategy to improve the homogeneity of fabricated specimens. Furthermore, both single melt and up to two remeltings were used. Findings The results indicate that remelting can be beneficial for density improvement as well as chemical and phase composition homogenization. Backscattered electron mode in scanning electron microscope showed a reduction in the presence of unmixed Ni and Ti elemental powders in response to increasing the number of remelts. The microhardness values of NiTi parts for the different numbers of melts studied were similar and ranged from 487 to 495 HV. Nevertheless, it was observed that measurement error decreases as the number of remelts increases, suggesting an increase in chemical and phase composition homogeneity. However, X-ray diffraction analysis revealed the presence of multiple phases regardless of the number of melt runs. Originality/value For the first time, to the best of the authors’ knowledge, elementally blended NiTi powders were fabricated via LPBF using remelting scanning strategies.

Nickel–titanium (NiTi) alloys have shown promise for a variety of biomedical applications because of their unique properties of shape memory, superelasticity, and low modulus of elasticity (Young's...

Artykuł przedstawia rekonstrukcję i interpretację sposobów wykorzystania lokali gastronomicznych oraz stoisk przedstawicieli przemysłu spożywczego w działach polskich na trzech wystawach międzynarodowych zorganizowanych w okresie międzywojennym (w Paryżu w 1925 i 1937 r. oraz w Nowym Jorku w 1939 r.). Podstawowym celem strony polskiej było skonstruowanie reprezentacji tożsamości kulturowej narodu, którego odrębność i prawo do samostanowienia stanowiły główną legitymizację istnienia II Rzeczpospolitej. Dlatego autorka zastanawia się, czy jedzenie można traktować jako pełnoprawny element tej reprezentacji oraz jakie wyobrażenia polskości konstruowano przy jego pomocy. Wskazuje, że w 1925 r. potencjał jedzenia nie został wykorzystany, natomiast w latach 1937 i 1939 było ono coraz skuteczniej włączane do reprezentacji polskiej tożsamości kulturowej. Zgodnie z zasadami gastrodyplomacji największy sukces odniósł kompleks gastronomiczny, w którym zaaranżowano sytuację staropolskiej biesiady.

Modern antiandrogens: abiraterone acetate (inhibitor of CYP17 cytochrome) and enzalutamide (irreversible inhibitor of androgen receptor) are the drugs that are increasingly often administered in treatment of castration-resistant prostate cancer. Despite their clinical efficacy, especially in terms of prolonged survival and improved quality of life of patients, they pose of problem for a practicing oncologist such as possible cardiovascular complications (particularly arterial hypertension), which may lead to the cessation of this form of therapy. This article provides a brief overview of the mechanisms responsible for the above complications, including practical recommendations in the event such complications arise. A simple scheme of action for control of cardiovascular risk factors has been presented, which can improve the prognosis in this population of patients.

Our recent exploration into the use of biodegradable metals and surface treatments resulting in sufficient strength for skeletal reconstruction applications has led to the need to test these devices’ cytotoxicity. More specifically, our group has developed a resorbable magnesium alloy, Mg–1.2Zn–0.5Ca–0.5Mn, that can be strengthened by heat treatment and coated with a ceramic layer offering time-certain resorption of a medical device. This in vitro study shows that these treatments do not result in cytotoxicity. Both heat-treated (HT) and HT + ceramic-coated (sol–gel) coupons demonstrated more than 70% viability. Thus, these processing steps are likely to be useful in producing biocompatible, resorbable implants that incorporate our Mg–1.2Zn–0.5Ca–0.5Mn alloy.

Of all the European Union’s member states, Poland has the most acute ambient air pollution problem. An urgent transition from solid-fuel heating ('e.g.' coal and wood) in the housing sector is required to improve air quality in the country. National regulations still allow the sale of solid fuels for heating, but some municipalities impose local resolutions with binding deadlines for solid-fuel bans. A real-world study covering 422 apartments in heritage tenements in Wrocław is presented. A link between domestic solid-fuel usage and tenure type is identified: solid fuels prevail in social housing. The transition to other forms of heating will adversely affect the inhabitants already vulnerable to fuel poverty. Solid fuel proves to be the least preferred heating option and is linked to substandard living conditions. Fuel poverty vulnerability for low-income households is established based on cost analysis for different heating options, thermal retrofit strategies, internal temperatures and apartment sizes. The results indicate that climate injustice is likely to occur for the poorest inhabitants due to their inability to afford increased costs. Policy implications to address this injustice are needed to ensure the transition from solid-fuel heating will avoid new vulnerabilities. 'Policy relevance' Domestic solid-fuel combustion for heating purposes is linked to poor air quality in urban areas in Poland. Heritage tenements are the most technically deprived building stock and their inhabitants are already vulnerable to fuel poverty. To improve air quality and respond to climate change, solid fuels need to be substituted with less polluting but more expensive heating options. Potential climate injustice (harm) is likely to occur if the poorest inhabitants cannot afford to heat their homes due to a ban on solid fuels. The change of heating needs to be combined with additional support (thermal retrofit and appropriate pricing of alternative fuels). Air quality-driven polices focused on solid-fuel eradication should not ignore fuel poverty already experienced mainly by social housing residents using expensive electric heating on a standard tariff. Fuel poverty has a gender aspect related to the gender pay gap that needs addressing.

NiTi alloys are widely used in different industrial and medical applications. Due to the inherent difficulty in the machining of these alloys, the use of Additive Manufacturing (AM) methods has become a popular method for their production. When working with NiTi alloys, there is a requirement on the precise control of their chemical composition, as this determines the phase transition temperatures which are responsible for their shape memory or superelastic behaviour. The high energies used in AM to melt the NiTi alloy leads to nickel evaporation, resulting in a chemical change between the batch powder and the additively manufactured part. Therefore, in AM techniques applied to different NiTi alloys, understanding the relationship between the melting strategy and nickel evaporation is crucial during the developing the desired chemical composition of the final-fabricated material. In this study, three NiTi alloys were fabricated using laser powder bed fusion (LPBF) starting from elementally blended Ni and Ti powders. Different melting strategies, including single and multiple melting, were studied in this work. Remelting improved the density and reduced cracking of the AM part. Microscopic observations, using a Scanning Electron Microscope (SEM) with a Backscattered Electron (BSE) detector, showed that the chemical homogeneity of the materials was enhanced by multiple remelting. Pure Ni and Ti were not found in any of the samples, proving that the applied melting strategies ensured good alloying of both powders. Regardless of the number of melting runs, X-ray diffraction (XRD) analysis showed the presence of NiTi (B2) and (B19′ ) phases, as well as NiTi2, Ni4Ti3 and Ni3Ti precipitates in all samples. The research demonstrated that, during the AM process, and depending on the melting strategy, 1.6–3.0 wt% of nickel evaporates from the material. It was demonstrated that the amount of evaporated nickel increased with the increasing number of melt cycles., peer-reviewed

Additive Manufacturing of scaffolds with controlled porosity has demonstrated its value in many fields such as tissue regeneration and filtration applications. However, there is a scarcity of reports investigating the manufacturing of scaffolds with hollow fibers. Mainly, this was due to the lack of proper tools (extrusion nozzles) that enable the production of such structures. In this study, a methodology of designing and manufacturing of a nozzle that can be fitted onto a fused filament fabrication 3D printer is proposed. Titanium laser powder bed fusion technology, coupled with chemical polishing, was used to produce the complex design of the nozzle with minimal post processing steps. Through this approach, we were able to produce a nozzle with the required internal structure. Numerical simulations and experimental analyses were conducted to better understand the melt flow behavior within the nozzle and the extrudate swell. The designed nozzle was capable of extruding tubular fibers with an outer and inner diameter of 1.3 mm and 0.5 mm, respectively. This, for example, enables the fabrication of tissue engineering scaffolds with hollow fibers. This proposed method for designing and manufacturing can be used to produce nozzles capable of 3D printing scaffolds that best suit the intended application.

Diatom frustules, with their diverse three-dimensional regular silica structures and nano- to micrometer dimensions, represent perfect model systems for biomimetic fabrication of materials and devices. The structure of a frustule of the diatom Didymosphenia geminata was nondestructively visualized using nano X-ray computed tomography (XCT) and transferred into a CAD file for the first time. Subsequently, this CAD file was used as the input for an engineered object, which was manufactured by applying an additive manufacturing technique (3D Selective Laser Melting, SLM) and using titanium powder. The self-similarity of the natural and the engineered objects was verified using nano and micro XCT. The biomimetic approach described in this paper is a proof-of-concept for future developments in the scaling-up of manufacturing based on special properties of microorganisms.

Dental implants are, nowadays, established surgical devices for the restoration of lost teeth. Considered as an alternative for traditional prosthetic appliances, dental implants surpass them in reliability and patient feedback. Local drug delivery around the implants promotes osseointegration and reduces peri-implantitis. However, there are currently no methods of a multiple, precise topical administration of drugs to the implant area. Engineering coatings on the implants, drug application on carriers during implantation, or gingival pockets do not meet all requirements of dental surgeons. Therefore, there is a need to create porous implants and other medical devices that will allow a multiple drug delivery at a controlled dose and release profile without traumatic treatment. Due to the growing demand for the use of biologically active agents to support dental implant treatment at its various stages (implant placement, long-term use of dental superstructures, treatment of the peri-implant conditions) and due to the proven effectiveness of the topical application of pharmacological biologically active agents to the implant area, the authors would like to present a review and show the methods and devices that can be used by clinicians for local drug administration to facilitate dental implant treatment. Our review concludes that there is a need for research in the field of inventions such as new medical devices or implants with gradient solid–porous structures. These devices, in the future, will enable to perform repeatable, controllable, atraumatic, and repeatable injections of active factors that may affect the improvement of osteointegration and the longer survival of implants, as well as the treatment of peri-implantitis.

This paper presents the results of measuring the final energy consumption for heating and domestic hot water (DHW) preparation and indoor conditions in 15 apartments located in pre-war tenement houses. The measurements were compared to the computed energy consumption. The calculations ware made based on the model calibrated by field measurements. The discrepancies between measurements and calculations were assessed using the energy performance gap (EPG). Calculations were made separately for energy for heating and for DHW preparation. Additionally, the results of EPG calculations for different levels of analysis are presented aiming at assessing the impact of weather, temperature in the surrounding zones and users&rsquo, behavior. Users&rsquo, behaviors influencing the size of the EPG were divided into typical (energy saving or excessive energy consumption) and forced (energy poverty, response to the apartment&rsquo, s surroundings, technical limitations. The connection between the heating sources and the heating habits has been clearly observed in the research. The former (typical) behaviors were the origin of the energy gap in the apartments heated with natural gas and district heating. The latter (forced) were the origin of the gap in the apartments heated with mostly electricity and solid fuel (with one exception: one apartment that utilized the district heating).

High emission linked with residential combustion for heating purposes is a pressing challenge for most cities in Poland. There are multiple uncertainties linked with the development of economically feasible and socially acceptable strategies for transition towards environmentally friendly domestic heating systems. Local municipalities lack basic inventories of heating systems in use or evaluation of the performance of retrofit buildings. Attitudes towards the planned changes are unknown. A field research that attempts to close this gap is presented. A novel approach based on building performance evaluation experience used multiple data sources and mixed research methods to learn about the heating in 422 occupied dwellings in Wroclaw, Poland. The research covered an urban quarter of historic tenements. The share of different heating systems, that is, solid fuel-based, gas, electric and district heating was established. An insight into the factors underpinning inhabitants’ attitudes towards heating their homes and potential change resulting from solid fuel ban implementation was gained. New themes emerged from the study revealing key areas of concern for solid fuel burning households, for example, thermal comfort and mould issues, fuel transport issues and high operational cost of water heating. None of these themes is present in current narrative advocating change. The majority of solid fuel burning households (86%) interviewed proved to be willing to change their heating system. This suggests the key barrier to change in this building typology is not down to negative social attitudes but other constraints discussed in the paper. Conclusions include recommendations for future studies aimed at estimating the scope of challenge linked with solid fuel bans in domestic sector and change in narrative aimed at convincing households to swap solid fuel combustion for other options.

The article presents a statistical analysis of the monthly consumption of hot water in apartment buildings. On this basis, a monthly model of hot water consumption in multi-family buildings was proposed. This model consists of two sub models: model of average daily consumption of domestic hot water and a model describing changes in consumption of hot water in individual months of the year. To construct the model of average daily consumption of hot water, data on the consumption of hot water was used out of 16 multi-family buildings from the period of two years. The data was supplemented with information on the housing structure in the building. The study of changes in hot water consumption in the following months was based on data obtained from 30 buildings. Statistical analysis showed a strong correlation between the monthly consumption of hot water, the outside temperature and holiday period.

The article presents the analysis of the hot water consumption in apartment buildings. This study was conducted basing on the data gathered from 626 apartments during two following years. By statistical analysis of the collected data, the correlation between the DHW consumption and both the size of the apartments and the number of occupants in the dwellings was evaluated. The dependencies between the hot water consumption and these two parameters were calculated. The results were compared to the data available in the literature. The article lists the areas of the greatest inaccuracies in the calculations basing on the available indicators and proposes an alternative method that corrects them. The results were used to develop a calculation model for daily hot water usage in multi-apartment buildings.

Multiple myeloma (MM) is the second most common hematological malignancy, with an annual incidence in Europe and the USA of about 4-6 cases per 100,000. Several forms of renal disease are found in the course of MM, including: cast nephropathy, light chain (LC) deposition disease and primary amyloidosis. Less frequent forms include: acute and chronic tubulopathies, neoplastic plasma cell infiltration and interstitial nephritis. In this paper, we discuss a case of 53-year-old male patient with MM who presented with massive proteinuria (24 g/24 h), mild renal insufficiency (eGFR 43 mL/min), and Fanconi-like syndrome (as reflected by normoglycemic glycosuria). In kidney biopsy glomeruli were normal, whereas abundant AFOG-positive deposits were found in the cytoplasm of proximal tubular epithelial cells. These deposits were strongly positive for kappa light chains on immunofluorescence. Electron microscopy revealed electron-dense, intracytoplasmic crystalloid deposits of variable shape (needle-shaped, round and rectangular), and size in the proximal tubular cells. This unusual variant of microscopic renal lesions in the course of MM coupled with coincidence of Fanconi-like and nephrotic syndrome as a clinical manifestation has not been reported to date.

The energy consumption for space heating and domestic hot water preparation are significant burdens of a polish household budget, especially in old tenement houses. Simultaneously, lowering the emission of pollutants is under the great importance and one of main goals to achieve in big cities. This policy results in the need of elimination of systems based on solid fuels. The article analyses the environmental and social consequences of the exchange of heat sources in such buildings in one of the quarters in Wroclaw. It presents how this change will affect the levels of low emission and costs of energy supply to tenement buildings.

Photograph by Mark Dorrian. Ella Chmielewska We are in the heart of the city, across from the National Museum and from what used to be the Communist Party Headquarters (Stock Exchange, 1991–2000; c...

The article discusses the influence of the cold water temperature on the amount of energy consumed for the purposes of the DHW preparation in multi-family buildings. The article begins with a presentation of the DHW consumption readings from a multi-family building, recorded on a monthly basis during the period of 4 years. The readings constituted the base for calculating the demand for energy for the purposes of the DHW preparation. Subsequently, basing on the output water temperature readings from the water treatment plant, it was proved that the temperature of the mains water fluctuates throughout the year. The review of the available literature, as well as the measurements, confirmed that it is necessary to develop a new model of the cold water temperature that would take into account the type of intake in a water treatment plant. The final part of the article presents how the accepted assumptions about the temperature of the mains water influence the consumption of energy for the purposes of the DHW preparation.

A method of analysis of viscosimetric data of weak electrolytes of 1–2 type has been elaborated. For this purpose, the precise measurements of density and viscosity of aqueous solutions of dicarboxylic acids (oxalic, malonic, succinic, glutaric, adipic, pimelic, dl -tartaric, dl -malic, maleic, fumaric and o -phthalic) have been conducted at 298.15 K. Modified Jones–Dole equations taking into account all chemical species existing in the solution as well as the phenomenon of dimerization of dicarboxylic acids have been proposed. The values of coefficients of the modified equations ( A , B 0 , B D ) have been determined. It has been shown that linear correlations exist between values of B coefficients and between them and the number of carbon atoms in the hydrocarbon part of acids coming from the same homologous series.

The viscosities and densities of aqueous solutions of monosodium salts of the dicarboxylic acids ([(CH2]n(COOH)2, n = 0–5 and tartaric, malic, maleic, fumaric and o-phthalic) of the type NaHA were measured in the concentration range 0.02–0.1 mol dm− 3 at 298.15 K. The equilibria existing in these solutions were considered. A modified form of the Jones–Dole equation describing the relative viscosity of solution of acidic salts was proposed. This is the first time that this type of equation for acidic salts which takes into account all equilibria occurring in the solution has been proposed.

An attempt has been undertaken to apply viscosimetric measurements for the examination of incomplete dissociation of symmetric electrolyte solutions. For this purpose precise measurements of the viscosity and density of dilute aqueous solutions of monocarboxylic acids (formic, acetic, propionic and valeric) have been conducted at 298.15 K. Modified Jones–Dole equations have been proposed for incompletely dissociated electrolyte solutions of 1–1 type. The data have been analysed taking into account dimerization of carboxylic acids. The B coefficients for all chemical species in the solution have been determined.

The electrical conductivities of NaBPh4, NBu4I, NaI, NaCl, NaBr and NaClO4 have been studied in the mixtures of propan-1-ol with water. The obtained results were analysed using the Fuoss–Justice equation. The individual limiting ionic conductivities of Na+, NBu4+, BPh4−, I−, Cl−, Br−, ClO4− ions have been determined using the Fuoss–Hirsch assumption. The dependencies of the limiting molar conductances Λo and Walden products Λoη versus mixed solvent composition have been discussed.

Viscosities and densities of aqueous solutions of sodium salts of monocarboxylic acids (formic, acetic, propionic, valeric, chloroacetic, trichloroacetic, glycolic, phenylacetic) and dicarboxylic acids (oxalic, malonic, succinic, glutaric, adypic, pimelic, dl -tartaric, dl -malic, maleic, fumaric, o -phthalic) have been measured in the concentration range 0.02–0.1 mol·dm − 3 at 298.15 K. The effect of hydrolysis of salts on viscosimetric data describing the objects under study was considered. The modified Jones–Dole equation taking into account the phenomenon of hydrolysis was proposed. The viscosity B coefficients for these electrolytes were determined.