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Spasticity is an important factor limiting independency and activity of daily living for post-stroke patients. Our aim was to develop a cost effective, customized, lightweight active orthosis, which is convenient for daily home use.The study describes the steps of the development by using cutting edge technologies, as 3D printing for the frame of the device and nitinol smart memory alloy as the active part of the orthosis. Polyamide and thermoplastic polyurethane materials were characterized in terms of mechanical behaviour in different ambient conditions. To access the feasibility of the orthosis 6 voluntary post-stroke patients were asked to test the functionality with manual function test, daily living functionality tests and Likert scale. Movement analysis was used to evaluate the range of movement in the orthosis.The results showed significantly higher functionality by using the orthosis on manual function test, most of the daily functional tests, also the overall personal impressions accessed by Likert scale were positive.The new anti-spastic orthosis is a smart, active, lightweight, personalized device, which seems to be effective help for post-stroke patients to overcome spasticity. According to the initial data it is suitable for home use, therefore offers a convenient solution for advanced rehabilitation.

Additive manufacturing technologies are dynamically developing, strongly affecting almost all fields of industry and medicine. The appearance of electrically conductive polymers has had a great impact on the prototyping process of different electrical components in the case of upper limb prosthetic development. The widely used FFF 3D printing technology mainly uses PLA (polylactic acid) and ABS (acrylonitrile butadiene styrene) based composites, and despite their presence in the field, a detailed, critical characterization and comparison of them has not been performed yet. Our aim was to characterize two PLA and ABS based carbon composites in terms of electrical and mechanical behavior, and extend the observations with a structural and signal transfer analysis. The measurements were carried out by changing the different printing parameters, including layer resolution, printing orientation and infill density. To determine the mechanical properties, static and dynamic tests were conducted. The electrical characterization was done by measuring the resistance and signal transfer characteristics. Scanning electron microscopy was used for the structural analysis. The results proved that the printing parameters had a significant effect on the mechanical and electrical characteristics of both materials. As a major novelty, it was concluded that the ABS carbon composite has more favorable behavior in the case of additive manufacturing of electrical components of upper limb prosthetics, and they can be used as moving, rotating parts as well.

The authors studied 36 obsidian-tipped spears in the Oceania collection of the Museum of Ethnography in Budapest. In addition to describing the objects from the Admiralty Islands collected before 1897, the paper provides a summary of the related ethnographic information, including the technological and technical details of spear point making and the characterisation of the obsidian raw material used. The blades used for making the obsidian points presented in this study showed no sign of standardisation (an indicator of advanced blade technology) in the spear point-making process. According to 19th-century ethnographic sources, the functional part of the points was the most important, and much time and effort were invested in ensuring that the blades were effective weapons. Later, as a sign of decline, primary production of obsidian blades ceased, and manufacturers started scavenging old artefacts and utilising waste and by-products. As a result, the blades decreased in size and became more irregular, and an increasingly large number included parts of the cortex, the crust of obsidian. After 1911, the relative importance of decoration increased, and the type became more standardised. The irregular shape of the spear points presented in the study and the thin, weak shafts with an awkward curvature raise questions about whether the spears were actual weapons. At the same time, the artistic decoration of the mounting sockets and ethnographic parallels suggest that the pieces in the collection were likely status objects instead.

The archaeological artefacts of the Vámoscsalád-Kavicsbánya site were discovered, collected and preserved by István Marton and his brother, András Marton, mineral collectors from Mesterháza, in about 2015. The slight elevation on a terrace of the Répce River was mined for the M86 highway in 2012–2013. Apart from knapped stone tools, the main subject of our paper, several polished serpentinite and greenschist tools have been recovered from the site, which could be in use between the Neolithic and the end of the Bronze Age. Only a few potsherds indicated a settlement of the Transdanubian Linear Pottery culture (TLPC). Of the Copper Age, Lengyel III and Baden pottery fragments and a clay spatula are worth mentioning. Almost the entire Bronze Age is represented, the most exciting find being a rim fragment of a bowl, decorated with an encrusted geometric pattern on both sides, of the Somogyvár–Vinkovci culture. Given the presumed mixed character of the knapped stone record of the Vámoscsalád-Kavicsbánya site (as the finds were not recovered from a closed stratigraphic context), we looked for possible cultural analogies and relationships, primarily those corresponding to the system of raw material–technology–typology. Although the pottery fragments of the TLPC recovered from the site are few and uncharacteristic, and the recovered finds may represent more than one phase, the knapped stone assemblage most likely represents the industry of the Middle Neolithic cultural unit, as suggested by raw material composition, technological features, type distribution and characteristics of the retouched tools. It is perhaps even possible that we are dealing with relatively old, if not the oldest TLP finds ever unearthed in the county.

András Marton has recently come into the possession of a small, chipped stone assemblage from the legacy of a German amateur mineral collector from Hamburg. Unfortunately, very little is known about the deceased and his collection. A part of the finds, including tools, was donated to the Institute of Archaeology of the Eötvös Loránd University. The lithic assemblage contains a total of 27 chipped stone artefacts made exclusively of Baltic flint. Concerning the raw material used, these flint varieties with the banded structure are rather unusual in Schleswig-Holstein. They are much more likely to originate from Lower Saxony or perhaps Mecklenburg-Western Pomerania. Apart from the general technological description of the assemblage, some pieces from these non-formal tools have been selected for a detailed description. The application of the “direct percussion with a hard hammer” technique and the presence of the thick artefacts contradict the Palaeolithic or Mesolithic origin of the assemblage, except for the flint axe (“Kernbeil”), which has a possible Mesolithic association. Alternatively, if the edges of the artefacts are not worn out or rolled, then along the edges of all artefacts traces of some kind of “cryoturbation retouch” are observable. In this case, the Palaeolithic dating of the finds is more plausible.

With the following short review, we would like to remember our departed German friend and archaeologist Peter Nierling. He conducted several field trips in North Africa, Algeria, Lybia, and Tunisia, and on two occasions, in 1997 and 1998, one of us (A. P.) accompanied him. During these travels, field surveys were carried out mainly in the region of Gafsa. In the wider vicinity of the classical Paleolithic/Mesolithic sites of El Mekta (de Gafsa) and Lalla (de Gafsa), several unknown archaeological sites and find spots were localized. After these trips, one of the authors (A. P.) received a relatively great assemblage of various content from Peter Nierling to enrich the Palaeolithic and Mesolithic collections of the Hungarian stone tool research. Although the Palaeolithic and Mesolithic of North Africa is not our specialization, below we give a brief review of the assemblages.

Attila Péntek recently acquired a large amount of chipped stone artefacts from the legacy of his departed friend Peter Nierling († 2017), archaeologist and field researcher in Hamburg. The aim of bequeathing the finds was to support the Palaeolithic and Mesolithic research in Hungary. The beneficiary catalogued the finds according to the sites and together with the necessary documentation handed them over to the Institute of Archeology of the Eötvös Loránd University.

Additive manufacturing (AM) is a versatile technology with potential applications in healthcare and medical instruments, where surface disinfection or sterilization is essential. This study comprehensively the effect of commonly used cost-effective disinfectants, ethanol (70 V/V%) and chlorine solution on the mechanical and thermal properties of flexible 3D printed materials. The following materials were tested before and after a 5-cycle surface disinfection: Flexfill TPE 90A, Phyton Flex (TPU) for material extrusion, Flexible (resin), Elastic 50A (resin) for vat photopolymerization and Flexa Black (TPU) material for powder bed fusion technology. Mechanical tests included tensile, compression, Charpy impact, flex resistance and stress relaxation tests, as well as Shore A hardness and volume measurements. The structure was analyzed using scanning electron microscopy (SEM)and Raman spectroscopy. The cytotoxicity was assessed using a A549 cell viability assay. The results show that after disinfection, significant changes occurred mainly in the tensile and Shore A properties, such as the tensile strength of the disinfected Flexible (resin) materials was 3.44 MPa ± 0.51 MPa (ethanol) and 2.62 MPa ± 0.31 MPa compared to the native 2.02 MPa ± 0.24 MPa. Interestingly, the applied surface disinfectants can negatively affect biocompatibility. Medical devices have been designed and fabricated based on the findings. Our findings can serve as a guide to the potential applications of commonly used 3D printed flexible materials in the biomedical field.

Continuous development of additive manufacturing technologies has reached new areas, including medical research and healthcare applications, where precision, highly accurate reproducibility, disinfection, or even sterility of the end product is essential. The study aims to critically evaluate the effect of different sterilization and disinfection methods for most commonly used additive manufacturing technologies and materials in medical device development: PLA (polylactic acid), PETG (polyethylene terephthalate glycol), ABS (acrylonitrile butadiene styrene), and HIPS (high impact polystyrene) for material extrusion technology (FFF; fused filament fabrication), polyamide (PA2200) for powder bed fusion technology (SLS; selective laser sintering), MED610™ for PolyJet™ material jetting, and standard Formlabs™ white resin (V4) for SLA (stereolithography) technology. The materials were tested before and after different sterilization and disinfection protocols, including treatment with 70% ethanol, chlorine solution, H2O2 plasma sterilization, autoclave and dry heat sterilization, applying 10 and 20 cycles in all cases. Bacteriostatic/fungistatic and sterility tests were performed using Escherichia coli, Enterococcus faecalis, and Candida albicans as reference strains. Cytotoxicity was evaluated using A549 cells. The samples showed significant structural or aesthetic alterations detected by various mechanical tests, scanning electron microscopy, or differential scanning calorimetry (DSC-TGA). No significant cytotoxic effect was revealed during the experiment. Our results can serve as a guide for the selection of effective sterilization and disinfection methods for the most common materials used in 3D printing in medical and healthcare applications.