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The analysis of three characters corresponding to different spaces and times shows the close link between literature and the history of medicine. On one hand, Don Quixote of La Mancha, who reflects the thought of the last years of the Renaissance and that has been assimilated in contemporary Mexico. On the other hand, Doctors Miguel Francisco Jiménez and Rita Levi Montalcini, who lived in the 19th and 20th centuries, respectively. Despite the years that separate these three personalities, many elements in common are observed that do not lose their validity: the value that is given to health, ethics, tenacity and experience to attain successful results. All three characters refer to the medicine of their time, their achievements and the promotion of humanism, always inherent to medicine.El análisis de tres personajes correspondientes a espacios y tiempos diferentes muestra el estrecho vínculo entre la literatura y la historia de la medicina. Por un lado, don Quijote de la Mancha, quien refleja el pensamiento de los últimos años del Renacimiento y ha sido asimilado en el México contemporáneo. Por otro lado, los doctores Miguel Francisco Jiménez y Rita Levi Montalcini, quienes vivieron en los siglos XIX y XX, respectivamente. A pesar de los años que separan a los tres personaje, se advierten numerosos elementos en común que no pierden vigencia: el valor que se otorga a la salud, la ética, la tenacidad y la experiencia para obtener resultados exitosos, entre otros. Los tres personajes aluden a la medicina de su tiempo, los logros alcanzados y la promoción del humanismo, siempre inherente a la medicina.

Pliable and water-resistant protein fibers from feathers were developed via continuous one-step spinning and crosslinking using sucrose-tetra-aldehydes. Though flexible protein fibers from feathers were developed, poor wet stability and low tenacity still limit the large and high-end applications of feather-derived fibers. Despite that saccharide aldehydes are considered as an efficient and sustainable crosslinker, substantial concerns such as generation of formaldehyde, high consumption of modifiers, loss of mechanical properties, yellowing, and decline in dyeability of fibers, exist after crosslinking. In this work, we controlled structures of crosslinkers and incorporated disaccharide-tetra-aldehydes into a continuous wet-spinning line. No formaldehyde was generated in the whole process. Protein fibers with controlled aldimine crosslinkages had not only a 92% tenacity retention after immersed in water for 1 week but also a substantial increase in mechanical properties. The dry and wet tenacity of feather-derived fibers was 120% and 90% of wool, respectively. Moreover, crosslinking from disaccharide-tetra-aldehydes retained the color of fibers and minimized the consumption of amine groups, the dyeing sites, on keratin. No toxicity was introduced by crosslinking. This work promotes resource recovery from poultry wastes, decreases the reliance of fiber industry on petroleum-based products, and diminishes environmental impact of fiber industries.

In the present study, an attempt is made to improve the ballistic performance of unidirectional (UD) ultra-high molecular weight polyethylene (UHMWP) fabrics through shear thickening fluid (STF) impregnation. Impact tests in the range of 250-700 m/s were conducted using an aero-ballistic range. It was observed that the ballistic limit ( V50) and the energy absorption of STF treated UD-UHMWP fabrics can be improved up to 5% and 13% respectively, corresponding to their neat ones. Increased energy absorption of STF treated fabric is attributed to the enhancement in the friction between layers of the STF-UHMWP fabric and the shear thickening effect. The effect of sample thickness of STF treated panels on the energy absorption, failure mechanism, and back face signature (BFS) is evaluated and compared with their neat counterparts. The damage was localised in the thinner panels (5 and 10 layers), and the layers were perforated through shear plugging near the impact region. The failure mode of thicker panels (20 and 30 layers) is accompanied by the tensile fracture of high tenacity fibres. It is concluded that the STF impregnation improves the ballistic resistance of UD-UHMWP fabric without affecting the flexibility and adding weight penalty.

In this study the influence of matrix type on plasma-treated high tenacity polypropylene fiber reinforced cementitious composites were investigated. The fibers were subjected to low frequency cold plasma of oxygen gas. Power rate of the generator was 50, 100 and 200 W, and duration was 0.5, 2 and 20 min. 25 × 60 × 300 mm prismatic samples were prepared with two type of matrices, and plasma-treated/untreated fibers. Scanning electron microscope was used to determine physical modifications on the fibre surface. Four point bending tests were conducted on prismatic samples. Matrices with treated and untreated fiber reinforcement were compared by means of flexural properties. Analysis of variences was applied to the plasma treated fiber reinforced groups. Test results showed that the flexural behaviour of composites was affected by plasma power and duration. There was physical modification for each plasma power and duration. The influence of plasma treatment on fiber-matrix bond properties was mainly affected by matrix type: weak matrix showed better flexural properties with low power and short duration plasma-treated fibers, whereas comparatively stronger matrix expressed greater flexural properties at higher power and longer durations when compared to untreated fiber reinforced composites.

Inter-yarn friction plays a pivotal role in determining the impact resistance of woven fabric based soft armour panels (SAPs). The current study presents a comparison of ballistic response of SAPs made from para-aramid, ultra-high molecular weight polyethylene (UHMWPE) and poly para-phenylene-2,6-benzobisoxazole (PBO) woven fabrics and demonstrates the importance of inter-yarn friction. Plain woven fabrics were prepared using para-aramid, UHMWPE and PBO yarns and SAPs of constant areal density was produced using multiple layers of these fabrics. It is found that despite lower tenacity and modulus of para-aramid fibres, in comparison to those of UHMWPE and PBO fibres, para-aramid SAP exhibits the lowest back face signature (BFS) owing to the highest inter-yarn friction. On comparing UHMWPE based SAPs made from fabrics with yarns of different fineness, fine UHMWPE yarn based fabric exhibits higher inter-yarn friction owing to more crossovers per unit length, which further translates into lower BFS of respective SAP. Therefore, while selecting fibres for soft body armour applications, inter-yarn friction should be considered along with the tensile properties.

The effect of chain extender Pyromellitic dianhydride (PMDA) on the comprehensive properties of the virgin (vPET) and recycled Polyethylene terephthalate (rPET) fibers was investigated. Five different weight fractions of PMDA were melt mixed with PETs to create long-chain branched (LCB) structures. The modified LCB-PET granules were melt spun into fibers using a capillary rheometer at 270 and 280 °C, and then aerodynamically stretched by an aspirator at seven take-up pressures. The different shear viscosity, thermal properties and spinnability of LCB-vPET and LCB-rPET, and the surface morphology, draw ratios, tenacity, elongation at break of PET fibers, as well as the performance-reliability plots using Weibull distribution were well discussed. A semi-empirical mathematical model further confirmed the exponential relationship between the tenacity and elongation at break of the PET fibers. This research depicts a visible window for academic and industrial researchers to produce PMDA modified PET fibers with desirable comprehensive properties.