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A prototype device was developed as a simple yet effective tool for the rehabilitation of individuals with upper limb paresis resulting from stroke. The primary objective of the design process was to create a portable rehabilitation device that could be remotely controlled by a therapist via a Bluetooth protocol. The device enables the execution of upper limb rehabilitation exercises and integrates essential modules for assessment, reporting, and user feedback (biofeedback). It comprises a base and three movable arms, each fitted with a container at its distal end. The central arm, positioned at the midpoint of the device’s housing, holds a storage container from which specific objects are retrieved by the user. This arm features an adjustable reach. The remaining two arms are equipped with task-specific containers mounted at their ends. The conceptual framework is based on the execution of various tasks displayed on a screen. The user retrieves objects from the central storage unit and places them into either the left or right container, as indicated. The target container is highlighted both visually on the screen and via an illuminated LED indicator. Pre-programmed sequences for object retrieval and placement are presented on the display, offering clear guidance for the correct positioning and ordering of blocks within the designated containers. The device includes 12 dedicated blocks varying in shape, colour, material, and texture. A mechatronic control system governs the container positioning and arm inclination, enabling a precise adjustment of range of movement according to the exercise’s requirements. A dedicated software system has also been developed for control and management. Functional testing of the prototype was conducted to assess the device’s effectiveness and practical applicability in rehabilitation settings.

Background Cytomegalovirus (CMV) is a common pathogen that affects individuals of all ages and establishes lifelong latency. Although CMV is typically asymptomatic in healthy individuals, infection during pregnancy or in immunocompromised individuals can cause severe disease. Currently, treatments are limited, with no prophylactic vaccine available. Knowledge of the current epidemiologic burden of CMV is necessary to understand the need for treatment and prevention. A systematic literature review (SLR) was conducted to describe the most recent epidemiologic burden of CMV globally. Methods Medline, Embase, and LILACS were searched to identify data on CMV prevalence, seroprevalence, shedding, and transmission rates. The SLR covered the time period of 2010–2020 and focused geographically on Australia, Europe, Israel, Japan, Latin America (LATAM), and North America. Studies were excluded if they were systematic or narrative reviews, abstracts, case series, letters, or correspondence. Studies with sample sizes < 100 were excluded to focus on studies with higher quality of data. Results Twenty-nine studies were included. Among adult men, CMV immunoglobulin G (IgG) seroprevalence ranged from 39.3% (France) to 48.0% (United States). Among women of reproductive age in Europe, Japan, LATAM, and North America, CMV IgG seroprevalence was 45.6-95.7%, 60.2%, 58.3-94.5%, and 24.6-81.0%, respectively. Seroprevalence increased with age and was lower in developed than developing countries, but data were limited. No studies of CMV immunoglobulin M (IgM) seroprevalence among men were identified. Among women of reproductive age, CMV IgM seroprevalence was heterogenous across Europe (1.0-4.6%), North America (2.3-4.5%), Japan (0.8%), and LATAM (0-0.7%). CMV seroprevalence correlated with race, ethnicity, socioeconomic status, and education level. CMV shedding ranged between 0% and 70.2% depending on age group. No findings on CMV transmission rates were identified. Conclusions Certain populations and regions are at a substantially higher risk of CMV infection. The extensive epidemiologic burden of CMV calls for increased efforts in the research and development of vaccines and treatments. Trial registration N/A.

This paper presents the results of research on the impact of the use of different tools and the shape of the additional rivet, on the geometric quality of the joint, the energy consumption of the forming process, the distortion of the steel samples, and the load capacity of the joints. The tests were carried out for DX51D steel sheets with a thickness of 1.5 [mm] joined by using three different sets of tools. A steel rivet with a hardness of 400HV1 and various shapes was used for the tests. In addition to the full rivet, two types of rivet were used, the first with a through hole and the second with a depth of hole of 3 [mm]. The holes in the rivet had different diameters: 1.0, 1.5, 2.0 and 2.5 [mm]. The influence of changing the shape of the rivet (hole and its diameter) on the change in forming force and energy consumption of the joining process was analyzed. The lowest forming force was achieved for a rivet with a through hole and a hole diameter of 2.5 [mm]. The lowest joint forming force was obtained for the die with movable segments. For joints made with three tool arrangements and a series with a modified rivet, the amount of sheet metal deviation was analyzed. Of the three cases of arrangement of tools used to form the joint, the largest deviation of the sheets occurred at the clinch joint formed with a solid round die. In the case of a series of clinch-rivet joints with a modified rivet, the greatest deviation of the sheets occurred for the rivet with a hole of 1.5 [mm]. Changes in the geometric structure of the joint were also studied, and changes in the surface of the sheets in the joint area were observed. The highest value of the interlock in the joint was obtained when a solid rivet was used in the clinch-riveting technology. The strength of the joints was also identified in the lap shear test and the energy consumption at failure was determined. The use of a rivet increased the maximum load capacity to almost twice that of the clinch joint. Graphical abstract

This paper presents the deformation of a joined sheet after the clinch riveting process. The DX51D steel sheet with zinc coating was used. The samples to be joined with clinch riveting technology had a thickness of 1 ± 0.05 mm and 1.5 ± 0.1 mm. The sheet deformation was measured before and after the joining process. The rivet was pressed in the sheets with the same dimension between the rivet axis and three sheet edges: 20, 30, and 40 mm. For fixed segments of the die, from the rivet side close to the rivet, the sheet deformation was greater than that of the area with movable segments. The movement of the die’s sliding element caused more sheet material to flow in the space between the fixed part of the die and movable segments. Hence, the sheet deformation in these places was smaller than for the die’s fixed element—the sheet material was less compressed. For sheet thickness values of 1.5 mm and a width value of 20 mm, the bulk of the sheet was observed. For a sheet width of 20 mm, it was observed that the deformation of the upper and lower sheets in the area of the rivet was greater than for sheet width values of 30 or 40 mm.

Clinching is a manufacturing method of mechanically joining two or more materials without the use of heat or additional components. This process relies on high plastic deformation to create a secure bond. Clinching technology is widely used for joining materials of various grades and thicknesses. Especially in the automotive industry, clinching is an alternative to resistance spot welding. However, the load-bearing capacity of clinched joints is comparatively lower when compared to resistance spot-welded joints. This research aimed to increase the load-carrying capacity of clinched joints. To enhance the load-bearing capacity of the clinched joints, localized modification of the microstructure was carried out, primarily focusing on the neck area of the joint. The alteration of the microstructure within the clinched joint was accomplished through the application of localized heating using the resistance spot welding method. The microstructure distribution in the clinched joint region was analyzed using light and scanning electron microscopy, as well as microhardness measurements. Two material grades, micro-alloyed steel HX420LAD+Z and dual-phase ferritic–martensitic steel HCT600X+Z, were tested. Each grade underwent five groups of ten samples, which were subjected to identical experimental conditions of local heating by resistance spot welding (RSW) and clinching. The utilization of RSW on the clinched joint region resulted in an average enhancement of 17% in the load-carrying capacity for material HCT600X+Z, and an average increase of 25% for material HX420LAD+Z.

The paper presents the pressed joint technology using forming process with or without additional fastener. The capabilities for increasing the load-carrying ability of mechanical joints by applying special rivets and dies were presented. The experimental research focused on joining steel sheet metal made of different materials. The joint forming was performed with the solid round die and rectangular split die for riveted joint forming. The load-carrying ability of joints was evaluated by measuring the maximum load force in the shearing test in the tensile testing machine. The effect of joint forming process on joined material strain was compared by measuring the microhardness of the joints.

In this thesis, the results of an experimental analysis of blanking angled hooks with a punch of a sloping face in a thin steel sheet with a hardness of 55 HRC are presented. The blanking punch was made of K340 cold-work tool steel. Tests were carried out for three values of clearance, 5%, 10%, and 15% of sheet thickness. The results of the analysis of the influence of the number of cuts made by the punch on the growth of the burr at the sheet edge were presented. Moreover, the influences of the clearance on the initial values of burr (bh), deflection (Hb), and the bending radius (Rb) of the hook have been shown. The influence of the friction path on the intensity of degradation of working surfaces and the blanking edges of the punch was also demonstrated. The obtained results allow the selection of the proper clearance and new tool materials for blanking blades working in particularly difficult tribological conditions.

The objective of this study is to compare the strength of riveted joints fabricated by traditional riveting (with pre-drilled holes) and self-piercing riveting (SPR) for different types of joints. Riveted joints were produced using steel and aluminum alloy rivets and two types of sheet material: 235JR steel sheet and EN AW 6060 aluminum alloy sheet with the following dimensions: length l = 100 ± 1 mm, width b = 50 ± 1 mm and thickness g = 2 mm. For all tested types of riveted joints (pre-drilled and SPR), 5 sets of joints were fabricated, each set containing 6 samples. The sets of joints differed with respect to the number of rivets (1, 2, 3, 4 and 6 rivets), joint type (single-, three- and four-riveted joints) and lap length. For all tested joints, the highest load capacity was obtained for self-pierced riveted joints, while the lowest - for pre-drilled joints with aluminum alloy rivets. In addition, it was found that the shear strength of self-pierced riveted joints is higher than that of aluminum and steel blind rivets.

Blanking is one of the most frequently used processes in sheet metal forming. Unlike other forming processes, such as stamping, blanking not only deforms the metal plastically to give the appropriate size and shape, but also ruptures the sheet metal in the desired zones. Among the others, blanking enables manufacturing of electric motor components, such as rotor or stator parts. The parts of the low power commutator motor of rotor and stator are made of generator sheets, which are really difficult to do from the machining point of view. The shock loads and high reaction of the sheet metal of separation surface to the punch surface are presented during the blanking process. In this paper, an investigation has been made to study the effects of punch–die clearance, tool materials, and tool coatings on the wear of blanking tools. In the paper, the feasibility analysis for various materials used for production of the tools for punching the generator sheets is presented.

In the process of mining coal considerable amounts of waste material are generated from which it is possible to produce aggregates which could find application in the reclamation of opencast excavations. One of the basic characteristic parameters which may be used to assess the suitability of aggregates for filling reclaimed opencast excavation is sulfur. Total and leachable forms of sulfur content from gangue samples were analyzed in the study. It has been shown that it is possible to select aggregates which are safe for the environment when the main assessment criterion was the percentage of sulfur in the aggregates and sulfate concentration in leaching tests. The research confirmed the role of sulfur as the most important and characteristic parameter which determines where and in what specific conditions the use of gangue or mining waste may be possible. Studies of sulfur content in the samples should be carried out with sufficient periodicity and in a manner enabling to obtain most reliable results which would refer to the entire batch of material. The statistical evaluation makes it possible to estimate to what extent the obtained results of sulfur content in the samples are close to actual values for the entire mass of the material.