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The article presents research on ergonomics, biophysical comfort and safety of protective clothing. The resistance of the structural, thermal and mechanical properties of five fabrics (CBXS400, GG200T, Twaron CT736, Dyneema HB26 and T1790C), differing in geometry and raw material composition used in space suits, to dangerous ionizing radiation (β and γ) occurring in space was tested. For both types of radiation, four identical one-time doses in the range of 25-100 kGy were used. The effect of the applied absorbed doses of β and γ radiation on the parameters of textiles influencing ergonomics and safety of the cosmonaut's work was verified by structural tests (micro-computed tomography and optical microcopy), thermal resistance tests (sweating guarded-hotplate) and strength tests (tensile testing machine). Experimental studies of thermal properties are supplemented with heat transport simulations using the finite volume method performed with 3D models of real textiles. The greatest reduction of thermal resistance for Twaron CT736 (-0.0667 m 2 ·°C·W -1 for 100 kGy of β-radiation) and Dyneema HB26 (-0.0347 m 2 ·°C·W -1 for 50 kGy of β-radiation) is observed. Strength tests have shown that all tested textiles are resistant to both types of radiation. Three textiles were selected to create a three-layer assembly with potential application in a cosmonaut's glove (Extravehicular Activity-EVA).

Preterm infants, due to immature and dysfunctional skin, have increased water loss through the skin and consequently a decreased body temperature. In order to develop protective garments for preterm infants, it is important to select materials that will protect the child against water and heat loss. The authors are currently involved in the development of protective garments for premature babies, which are similar to baby clothes and contain a membrane that is partially permeable for vapor in combination with textile materials. This article presents the study of materials intended for the production of protective garments for pre-term infants. Samples of materials were investigated to determine biophysical comfort (tests of heat resistance, vapor resistance according to PN-EN ISO 11092:2014-11 and air permeability according to PN-EN ISO 9237) and porosity, surface mass in accordance with PN-EN 12127, and thickness in accordance with PN-EN ISO 5084. In order to determine the porosity of materials and to visualize the structure, tests on computer microtomography were carried out. The mechanical properties of the tested materials and the evaluation of the total hand value were characterized; the samples were tested on the KES device. The aim of this study was to select the most suitable fabrics for protective garments for premature infants to prevent excessive heat and moisture loss from the body, which can lead to hypothermia. For laminates, the optimal results of vapor resistance and heat resistance were obtained for laminate (15 g·m -2 PE foil + 15 g·m -2 PP non-woven), with a level of thermal resistance of 0.0766 m 2 ·K·W -1 and vapor resistance of 188.729 m 2 ·Pa·W -1 , and for laminate (15 g·m -2 PE foil + 10 g·m -2 PP non-woven), with a level of thermal resistance of 0.0683 m 2 ·K·W -1 and vapor resistance of 164.085 m 2 ·Pa·W -1 . For knitted fabrics, knitwear single cotton 155 g·m -2 showed the highest thermal resistance (0.0296 m 2 ·K·W -1 ), and knitwear interlock polyester 120 g·m -2 showed the lowest thermal resistance (0.0179 m 2 ·K·W -1 ). Knitwear cotton 120 g·m -2 had the highest water vapor resistance (8.402 m 2 ·Pa·W -1 ), while knitwear interlock polyester 130 g·m -2 sample had the lowest resistance (6.356 m 2 ·Pa·W -1 ). Garments for premature babies should have moisture barrier properties and high thermal insulation. They should also be characterized by optimal air permeability properties. Sample two-layer laminate (15 g·m -2 PE foil + 15 g·m -2 PP non-woven) had the best vapor resistance and thermal insulation properties. Moreover, this sample was characterized by good air permeability and surface weight compared to the other laminate samples. During the design of garments for premature babies, it is important to reduce the surface weight to as low as possible. Among the knitted fabrics, a knitwear single cotton 120 g·m -2 knitwear polyester interlock 120 g·m -2 was selected for having the best THV or tactile comfort. In addition, these knits were chosen for their lower surface weight. Based on the conducted tests, two-layer laminate (15 g·m -2 PE foil + 15 g·m -2 PP non-woven), the knitwear single cotton 120 g·m -2, and knitwear polyester interlock 120 g·m -2 were selected for further research.

A knitted implant, unilaterally modified with plasma-assisted chemical-vapor deposition (PACVD), and with a nano-layer of fluorine derivative supplementation, for reducing the risk of complications related to adhesions, and the formation of a thick postoperative scar was prepared. The biological evaluation of designed or modified medical devices is the main aspect of preclinical research. If such studies use a medical device with prolonged contact with connective tissue (more than 30 days), biocompatibility studies require a safety assessment in terms of toxicity in vitro and in vivo, allergenicity, irritation, and cancerogenicity, reproductive and developmental toxicity. The ultimate aspect of biological evaluation is biofunctionality, and evaluation of the local tissue response after implantation, resulting in the determination of all aspects of local biocompatibility with the implemented synthetic material. The implantation of PACVD-modified materials in muscle allows us to estimate the local irritation effect on the connective tissue, determining the risk of scar formation, whereas implantation of the above-mentioned knitted fabric into the abdominal wall, assists with evaluating the risk of fistula formation-the main post-surgical complications. The research aimed to evaluate the local reaction of the soft tissues after the implantation of the knitted implants modified with PACVD of the fluoropolymer in the nanostuctural form. The local effect that occurred during the implantation of the designed implants was quantitatively and qualitatively evaluated when PACVD unmodified (reference), and modified medical devices were implanted in the abdominal cavity (intra-abdominal position) for 12 or into the muscles for 56 weeks. The comparative semi-quantitative histological assessment included the severity of inflammatory cells (multinucleated cells, lymphocytes, plasma cells, macrophages, giant cells) and the tissue response (necrosis, neovascularization, fibrosis, and fat infiltration) on a five-point scale. The knitted implants modified by PACVD did not indicate cumulative tissue response when they were implanted in the muscle and intra-abdominally with direct contact with the viscera. They reduced local tissue reaction (score -2.71 after 56 weeks of the implantation) and internal organ adhesion (irritation score -2.01 and adhesion susceptibility -0.3 after 12 weeks of the implantation) compared with the reference (unmodified by PACVD) knitted implant, which had an identical structure and was made of the same source.

The thermal properties of clothing products are influenced by external environmental parameters, such as temperature, humidity, air flow and parameters related to the user's body, which mainly include temperature and humidity. Depending on the type of raw material, its thickness and the material manufacturing technique, clothing products are characterised by certain insulating properties to protect the human body from external factors. A multilayer system made of different material groups can change the thermal insulating capacity significantly, which cannot be determined by the testing of individual layers used in the production. In order to determine the influence of weather conditions on thermal insulation and air permeability, tests were carried out for two types of sleeping bags (summer and autumn) produced by the same manufacturer, differing in insulation thickness. Simulations were carried out using SolidWorks and verified using a Newton thermal mannequin. During tests, both the temperature (range from -20 °C to 20 °C) and humidity values were changed (range 40-80% humidity). For sleeping bags, the effective thermal insulation decreases along with the increase of temperature and decrease of humidity. It can be observed, for the autumn sleeping bags, that for a temperature of 20 °C and humidity of 60%, the thermal insulation is 1.063 m 2 ·K·W -1 , while for a temperature of -20 °C and humidity of 60% thermal insulation increases significantly and amounts to 1.111 m 2 ·K·W -1 . A similar situation occurs for the effective thermal insulation of a summer sleeping bag (20 °C/60% thermal insulation is 0.794 m 2 ·K·W -1 , while for -20 °C/60%-0.851 m 2 ·K·W -1 . During the tests, the humidity and temperature between the layers of the clothing system were also controlled, in order to learn more about the influence of these parameters on the thermal insulation properties of the sleeping bags.

This article presents research on ergonomics and physiological comfort of protective clothing. Biophysical properties of selected three-layer textile assemblies that differ in geometry and raw material composition for the production of types of mummy sleeping bags for premature babies were investigated. The tests included measurements of air permeability, thermal resistance and water vapor resistance (both by means of human skin model), thermal insulation, and water vapor resistance (both using newborn manikin). Experimental research was supplemented by modeling the thermal insulation of the assemblies by designing their 3D models using selected CAD software and applying the finite volume method. The obtained results allowed the evaluation of the influence of different geometry and the raw material composition of the proposed assemblies on the performance parameters of protective clothing.

A parastomal hernia is a common complication following stoma surgery. Due to the large number of hernial relapses and other complications, such as infections, adhesion to the intestines, or the formation of adhesions, the treatment of hernias is still a surgical challenge. The current standard for the preventive and causal treatment of parastomal hernias is to perform a procedure with the use of a mesh implant. Researchers are currently focusing on the analysis of many relevant options, including the type of mesh (synthetic, composite, or biological), the available surgical techniques (Sugarbaker's, "keyhole", or "sandwich"), the surgical approach used (open or laparoscopic), and the implant position (onlay, sublay, or intraperitoneal onlay mesh). Current surface modification methods and combinations of different materials are actively explored areas for the creation of biocompatible mesh implants with different properties on the visceral and parietal peritoneal side. It has been shown that placing the implant in the sublay and intraperitoneal onlay mesh positions and the use of a specially developed implant with a 3D structure are associated with a lower frequency of recurrences. It has been shown that the prophylactic use of a mesh during stoma formation significantly reduces the incidence of parastomal hernias and is becoming a standard method in medical practice.

In this study, differences in the kinetics of the thermal-supported hydrolytic degradation of polylactide (PLA) wet spinning fibres due to material variance in the initial molecular and supramolecular structure were analysed. The investigation was carried out at the microstructural and molecular levels by using readily available methods such as scanning electron microscopy, mass erosion measurement and estimation of intrinsic viscosity. The results show a varying degree of influence of the initial structure on the degradation rate of the studied PLA fibres. The experiment shows that hydrolytic degradation at a temperature close to the cold crystallization temperature is, on a macroscopic level, definitely more rapid for the amorphous material, while on a molecular scale it is similar to a semi-crystalline material. Furthermore, for the adopted degradation temperature of 90 °C, a marginal influence of the pH of the degradation medium on the degradation kinetics was also demonstrated.