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The objective of the present work was to evaluate the surface wettability of commercially available polymeric protective gloves, as well as to determine the effects of their surface topography in conjunction with the glove material on the hydrophobic properties of the final products, together with surface free energy (SFE) and work of adhesion.

Heated gloves have been gaining popularity due to increasing work safety demands. The objective of the present work was to evaluate the effects of the presence of chemical hand warmers in protective gloves. The study involved three types of gloves appropriate for work activities performed in cold environments. Several hand warmer variants were designed, differing in terms of shape and location within the glove, which are of great relevance to the comfort of use. Manual dexterity tests were designed to approximate real conditions of the work environment, allow for simulation of occupational activities, and involve various aspects of manipulation.

The objective of the work was to study the properties of functional insoles for protective footwear using an original methodology by simulating the dynamic real-life conditions. Two insole variants were examined; both are made from a three-layer composite with the middle layer being a polypropylene melt-blown nonwoven. The variants differed in terms of the presence or absence of a superabsorbent polymer (SAP) and a biocide in the middle layer. Insole samples were subjected to pressure and examined in terms of the adsorption and desorption of acidic and alkaline liquids, followed by tear strength experiments. In addition, the insoles were placed in protective footwear and the microclimate existing inside the resulting system was determined using T/RH sensors by means of three complementary methods: under controlled climatic conditions, on a thermal foot model, and on human subjects. The results clearly indicate that insoles containing SAP are more effective than those without SAP in terms of both hygienic and mechanical properties.

The objective of the present work was to evaluate the surface wettability of commercially available polymeric protective gloves, as well as to determine the effects of their surface topography in conjunction with the glove material on the hydrophobic properties of the final products, together with surface free energy (SFE) and work of adhesion. The geometric structures imparted to the surface led to different levels of hydrophobicity and SFE. Most of the studied materials were characterized by good wettability properties. It was shown that a textured surface topography affects wettability. The highest SFE was found for nitrile butadiene rubber materials. All materials except for nitrile butadiene rubber exhibited good hydrophobic properties and relatively low work of adhesion. [ABSTRACT FROM AUTHOR]

This paper discusses the cross-linking behaviors, mechanical and dynamical properties, and flammability of elastomeric composites containing unconventionally cured chlorosulfonated polyethylene (CSM). The purpose of this work was to verify the CSM ability to cross-link with iron(II,III) oxide (Fe3O4) and to produce flame retardant materials. During the first series of tests, three types of CSM were used, differing in the content of bound chlorine (29–43%). The results showed that the CSM with 43% bound chlorine (Hypalon 30, CSM43) was the most advantageous type of chlorosulfonated polyethylene in terms of its properties. It exhibited a short vulcanization time, a high degree of cross-linking, and very good mechanical properties. In the next stage, the CSM composites with various fillers (talc, arsil, kaolin, chalcedonite, or carbon black) were prepared, because filled rubber materials are of the greatest practical importance. The cross-linking kinetics, equilibrium swelling, mechanical and dynamic properties as well as flammability were studied. It was found that the addition of fillers led to a decrease in the degree of cross-linking, an increase in the vulcanization time (in the case of talc, arsil, or kaolin), an increase in the overall mechanical strength (in the case of carbon black, arsil or talc). All filled vulcanizates proved to be non-flammable, as the specific oxygen index value exceeded 37.5%. [ABSTRACT FROM AUTHOR]

The objective of the work was to study the properties of functional insoles for protective footwear using an original methodology by simulating the dynamic real-life conditions. Two insole variants were examined; both are made from a three-layer composite with the middle layer being a polypropylene melt-blown nonwoven. The variants differed in terms of the presence or absence of a superabsorbent polymer (SAP) and a biocide in the middle layer. Insole samples were subjected to pressure and examined in terms of the adsorption and desorption of acidic and alkaline liquids, followed by tear strength experiments. In addition, the insoles were placed in protective footwear and the microclimate existing inside the resulting system was determined using T/RH sensors by means of three complementary methods: under controlled climatic conditions, on a thermal foot model, and on human subjects. The results clearly indicate that insoles containing SAP are more effective than those without SAP in terms of both hygienic and mechanical properties. [ABSTRACT FROM AUTHOR]

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The middle region of the digestive system, the midgut of freshwater shrimp Neocaridina davidi is composed of a tube-shaped intestine and the hepatopancreas formed by numerous caeca. Two types of cells have been distinguished in the intestine, the digestive cells (D-cells) and regenerative cells (R-cells). The hepatopancreatic tubules have three distinct zones distinguished along the length of each tubule--the distal zone with R-cells, the medial zone with differentiating cells, and the proximal zone with F-cells (fibrillar cells) and B-cells (storage cells). Fasting causes activation of cell death, a reduction in the amount of reserve material, and changes in the mitochondrial membrane potential. However, here we present how the concentration of ROS changes according to different periods of fasting and whether re-feeding causes their decrease. In addition, the activation/deactivation of mitochondrial superoxide dismutase (MnSOD) was analyzed. The freshwater shrimps Neocaridina davidi (Crustacea, Malacostraca, Decapoda) were divided into experimental groups: animals starved for 14 days, animals re-fed for 4, 7, and 14 days. The material was examined using the confocal microscope and the flow cytometry. Our studies have shown that long-term starvation increases the concentration of free radicals and MnSOD concentration in the intestine and hepatopancreas, while return to feeding causes their decrease in both organs examined. Therefore, we concluded that a distinct relationship between MnSOD concentration, ROS activation, cell death activation and changes in the mitochondrial membrane potential occurred. [ABSTRACT FROM AUTHOR]