Quality Assessment of Socks Produced from Viscose and Lyocell Fibers.

Most casual socks are produced from cotton and are usually combined with synthetic fibers. The suitability of viscose and lyocell fibers for knitting socks needs to be investigated further. Therefore, three series of plain socks were produced, composed in the largest content from single-spun viscose or lyocell yarns fully plated with texturized polyamide 6.6 multifilament yarn. The quality of three types of main yarns manufactured by ring, open-end rotor, and air-jet spinning processes and two types of polyamide plating yarns used in the production of socks were assessed together with the structural, usage, and comfort quality of the socks before and after simulating household laundering. In comparison with cotton socks produced from ring-spun yarns under the same conditions, the results showed that viscose and lyocell socks have better moisture absorption and breathability, comparable dimensional stability, and lower abrasion resistance; lyocell socks have lower thermal resistance; and viscose socks are less prone to surface pilling after wet pretreatment.

Evaluation of DNA-Damaging Effects Induced by Different Tanning Agents Used in the Processing of Natural Leather-Pilot Study on HepG2 Cell Line.

For a long time, the production and processing of cowhide was based on the use of chrome tanning. However, the growing problem with chromium waste and its negative impact on human health and the environment prompted the search for more environmentally friendly processes such as vegetable tanning or aldehyde tanning. In the present study, we investigated the DNA-damaging effects induced in HepG2 cells after 24 h exposure to leather samples (cut into 1 × 1 cm2 rectangles) processed with different tanning agents. Our main objective was to determine which tanning procedure resulted in the highest DNA instability. The extent of treatment-induced DNA damage was determined using the alkaline comet assay. All tanning processes used in leather processing caused primary DNA damage in HepG2 cells compared to untreated cells. The effects measured in the exposed cells indicate that the leaching of potentially genotoxic chemicals from the same surface is variable and was highest after vegetable tanning, followed by synthetic tanning and chrome tanning. These results could be due to the complex composition of the vegetable and synthetic tanning agents. Despite all limitations, these preliminary results could be useful to gain a general insight into the genotoxic potential of the processes used in the processing of natural leather and to plan future experiments with more specific cell or tissue models.

Antibacterial Properties of Non-Modified Wool, Determined and Discussed in Relation to ISO 20645:2004 Standard.

Wool is considered to possibly exhibit antibacterial properties due to the ability of wool clothing to reduce the build-up of odor, which arises from the microbial activity of skin microbiota. Indeed, when tested with a widely used agar diffusion plate test method, even wool or other textiles not treated with any antimicrobial agent can be interpreted to show certain antibacterial effects due to the lack of growth under the specimen, as instructed in ISO 20645:2004 standard. Therefore, we analyzed in detail what happens to bacterial cells in contact with untreated wool and cotton fabric placed on inoculated agar plates by counting viable cells attached to the specimens after 1 and 24 h of contact. All wool and several cotton samples showed no growth under the specimen. Nevertheless, it was shown without a doubt that neither textile material kills bacteria or inhibits cell multiplication. A reasonable explanation is that bacterial cells firmly attach to wool fibers forming a biofilm during multiplication. When the specimen was lifted off the nutrient agar surface, the cells in the form of biofilm remained attached to the wool fibers, removing the biomass and resulting in a clear, no growth zone underneath it. By imaging the textile specimens with X-ray microtomography, we concluded that the degree of attachment could be dependent on surface topography. The results indicate that certain textiles, in this case, wool, could exhibit antibacterial properties by removing excess bacteria that grow on the textile/skin interface when taken off the body.

Evaluating thermophysiological comfort using the principles of sensory analysis.

Thermophysiological comfort applies to the way in which clothing lets through or retains heat and moisture and helps the body retain heat balance in rest position or at various levels of activities. In this paper, the principles of sensory analysis are used to define the protocol of new method for the evaluation of thermophysiological comfort wearing different garments. Sensory analysis was chosen because as a scientific discipline that applies experiment principles using human senses is used for the evaluation of consumer goods. Test protocol using assessors described in this paper consists of the following steps: defining the interview content, finding potential assessors and making an interview, creating a survey, conducting a survey, group discussion, test and group discussion scoring, selection of assessors, assessment preparation and subjective assessment. On average the most distinctive increase in the sensation of warmth was recorded for the polyester clothing ensemble, and the lowest one for the cotton clothing ensemble. Concerning the average grades of comfort given by assesors, the most comfortable clothing ensemble is the one made of viscose. It was also found out that the method is especially suitable if a representative group of assessors is formed.

Biomechanical trial of modified flexor tendon sutures: an in vitro study.

Proven benefits of early active mobilisation for intra-synovial flexor tendon repairs have inducted new criteria for a 'perfect suture'. This study has examined different variations of modified Kessler's suture, which could fulfil the new criteria. A total of 93 swine extensor tendons were transected, repaired and tested using a dynamometer with constant rate of extension. The first part of study tested clinically the most used modified Kessler suture, a variation of double modified Kessler suture and intact tendons as a control group. Further variations in the second part of study were due to type of suture, location and number of the knots and type of peripheral suture. According to the results, the tested version of double modified Kessler suture with crossed peripheral suture was the strongest one among all tested variations. The ultimate force for the authors preferred modification of the double modified Kessler (DMK) is significantly higher than modified Kessler suture. The version of DMK with crossed peripheral suture is the strongest one among all tested variations. The lowest strength manifests variation with two knots between tendon ends. The variations with interlocked and outsided knot or monofilament tread are not statistically significant regarding ultimate force. The frequency of suture failure events (suture pull out or tendon and/or suture rupture) is equal respecting braided or monofilament suture. The preferred modification of the double modified Kessler (DMK) suture with crossed peripheral suture is the strongest one among all tested variations and could achieve, concerning range of force, early active mobilisation. Further variations due to the type of thread and location, type and number of the knots did not show statistical significance.

The comparison of human perception to the measured sweat transfer rate.

The subjective investigation, that is focused on the sensations of a person, is a good tool for the evaluation of an environment that group of people consider comfortable. In the experiment reported here, participants were dressed into 1-layer and 2-layer clothing systems. They performed physical activity and rated the subjective perception of comfort, as well as the thermal and moisture sensation. The aim of this investigation is to compare the subjective human perception during the physical activity wearing different clothing systems to the objective results of sweat absorption.

Comparison of subjective and objective measurement of sweat transfer rate.

Sweat absorption is investigated using the subjective and objective methods. The subjective investigation analyses the physiological responses of male and female volunteers wearing two kinds of textile fabrics (cotton and polyester) during certain physical activity. The subjects were exposed to the different conditions of ambient temperature (23, 26, 29 and 32 degrees C) and constant relative humidity of 67 +/- 3%. In the objective investigation the sweating guarded hotplate (SGHP) system was used that stimulates the processes of sweat transfer between the human skin, textile material and environment. The results of mass absorption obtained from the objective measurement on the sweating guarded hotplate show the similar trend as the results obtained during the subjective measurement.