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Gloves
Published in Robert N. Phalen, Howard I. Maibach, Protective Gloves for Occupational Use, 2023
Marie-Noëlle Crépy, Pierre Hoerner
NR is a natural product that is well known since ancient times. It is harvested from rubber trees (mostly Hevea brasiliensis). When an incision is made on the bark of the tree, a liquid sap naturally flows to heal this incision. The sap is composed of colloidal particles of polyisoprene of high stereospecificity (99% of cis-1,4-polyisoprene) dispersed in water. The generic name of colloidal polymeric particles dispersed in water is “latex”; hence, the rubber tree sap is called “natural rubber latex.” The latex particle size ranges from 0.1 µm to 10 µm, as shown in Figure 3.1.
Aging, Growth and Maturation
Published in Wilmer W Nichols, Michael F O'Rourke, Elazer R Edelman, Charalambos Vlachopoulos, McDonald's Blood Flow in Arteries, 2022
The data in Figure 15.32 (see Nichols et al., 2011, 6th edition) are given as a guide. No data are available on the fatiguing properties of elastin. This may be different from that of natural rubber, but it would be expected to take the same general form. If elastin were to act like rubber as described by Osler (1892), the data in the figures show that the effects of repetitive stretch could explain the observations of the progressive fracture of elastin fibers from at least early adulthood in the central elastic but not in other arteries. Data could also explain the increased prevalence of degeneration in hypertension, where (at least initially according to Boutouyrie et al. (1992) greater pressure fluctuation could cause greater stretch and the virtual absence in experimental animals, where in a lifespan nowhere near 1 billion cycles of stretch is ever achieved. Progressive dilatation of the affected arteries is an expected consequence of elastin fiber fracture, as is fibrous remodeling (Lam et al., 2010). As expected, persistently elevated heart rate is associated with acceleration of aortic stiffening (Palatini and Parati, 2010).
Latex Allergy
Published in Pudupakkam K Vedanthan, Harold S Nelson, Shripad N Agashe, PA Mahesh, Rohit Katial, Textbook of Allergy for the Clinician, 2021
Ronald D DeGuzman, Pudupakkam K Vedanthan
Despite the decrease in latex hypersensitivity due to increased recognition and primary prevention measures, allergy to natural rubber latex continues to be a significant concern, particularly in the health care setting. Providers need to be aware of the clinical presentation and the diagnostic testing modalities available in order to accurately identify latex-allergic individuals. Patient education and establishing of avoidance measures in the home and work environment is critical in order to prevent further exposures and potential reactions.
Whole-body vibration exposure of roller compactor operators: characteristics and effect of waste rubber in damping the vibration
Published in International Journal of Occupational Safety and Ergonomics, 2021
Migunthanna Kariyakaranage Janitha Madhavie, Gardiyas Hewawasam Mummullage Jimila Subashi De Silva
Waste rubber, generated as a by-product of the rubber manufacturing process, has high potential in damping vibration similar to natural rubber. Sri Lanka is the seventh largest exporter of natural rubber and ranks among the top 10 largest rubber producers in the world [12]. The Sri Lankan rubber industry includes both manufacturing of raw rubber and finished products. The manufacturing processes generate waste rubber in different forms and different compositions. Based on the production procedures and item types, the quality and the quantity of waste produced may varies. However, there is no proper usage for this waste rubber. Rubber is commonly used as a vibration isolation material and generally possesses good damping properties, which can be further improved by compounding fillers and chemicals [13]. Usually polar structured rubber polymers improves the compatibility between layers and enhances the damping property, wear property and strength. Nitrile rubber has such a polar structure and is rich with damping ability [14]. In this study, the performance of a rubber mat produced by adding waste rubber sludge generated in the glove manufacturing industry was evaluated.
Frequency analyses of posturography using logarithmic translation
Published in Acta Oto-Laryngologica, 2020
Hiroki Watanabe, Ayane Makabe, Chiaki Hirai, Takamori Takeda, Keiji Honda, Shinichi Demura, Takeshi Tsutsumi
The foam rubber material was manufactured from natural rubber with a tensile strength of 2.1 Kgf/cm2, a density of 0.06 g/cm2, elongation stretch percentage of 110% and thickness of 3.5 cm. Body sway trajectory, as indicated by shifts in the centre of pressure (CoP) on the force platform, was recorded at a sampling frequency of 20 Hz. The power-spectral data of the CoP in the anteroposterior and lateral directions were obtained with the maximum entropy method. Power-spectral data were logarithmically translated for quantitative evaluation. To visually emphasize the characteristics of each age group and SCD patients, we calculated subtracted product between data of each group and the average of all healthy subjects to plot on the logarithmic frequency diagram. Statistical differences at each frequency were identified with the paired t-test for the healthy subjects, while the t-test was used for comparisons between the SCD patients and healthy subjects.
Skin reactions to latex in dental professionals – first Croatian data
Published in International Journal of Occupational Safety and Ergonomics, 2019
Iva Japundžić, Liborija Lugović-Mihić
In view of the frequency of undesirable reactions to latex, it is very important to identify their clinical manifestations early in order to ensure their adequate prevention and treatment. This is why a number of international campaigns have been organized to raise awareness. These have contributed to the decrease in the frequency of these types of skin lesions. A recent 2015 Danish study examined the prevalence trend in sensitized subjects and in those with a clinical allergy to the natural rubber in latex (2002–2013), and included testing for latex in 8580 patients [20]. The results indicate that latex sensitization has dropped from earlier results 6.1% (2002–2005) to 1.9% (2006–2009) and then to 1.2% (2010–2013). Also, the frequency of clinical manifestations to latex allergies has dropped from 1.3% (2002–2005) to 0.5–0.6% (2006–2013), indicating a substantial drop in the number of persons sensitized to latex or clinically manifesting a latex allergy. Other research has also shown a gradual decrease in the frequency of reactions to latex (from 8.5 to 4.3%), which is explained by the use of better quality latex gloves with less allergens [21,22].