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Phenol is used in the manufacturing process of phenolic resins from which residues remain that must be sent for confinement. For that reason, in this study, the wastewater of a resin factory was analyzed to isolate the bacteria present, identify them by molecular methods and finally evaluate their impact on bioremediation treatment. A total of 15 bacteria were isolated, of these, eight belong to the genus Bacillus spp. All bacteria were individually multiplied and inoculated in clusters in 15 L reactors which were carefully monitored for pH, electrical conductivity, chemical oxygen demand and temperature. The acquired data were analyzed using ANOVA with repeated measurements. The first test revealed that native bacterial communities reduce the phenol content by up to 20% and COD by 49%, which is significant with respect to the reactor not being inoculated with bacteria. Furthermore, when a mathematical model was applied to the reactors, it was shown that the bacteria require an adaptation time of approximately 100 h. A second test where the inoculation was interspersed with the addition of lime as a flocculant showed that, even though the reduction in phenol and COD was lower than in the previous test, the difference between treatments and control is statistically significant (α ≤ 0.05).

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Revisamos la antisepsia obstétrica, desarrollada a mediados del siglo XIX por O.W. Holmes y especialmente por I. Semmelweis, con una aportación fundamental en el control de infecciones, el lavado de manos previo a la atención al parto, lo que supuso un avance definitivo en la lucha contra la infección puerperal. Aproximadamente dos décadas más tarde, J. Lister introduce la antisepsia quirúrgica, que supuso asimismo un gran avance en el desarrollo de la cirugía, al reducir sustancialmente las infecciones y permitir intervenciones que hasta entonces no era posible realizar. En las postrimerías del siglo XIX, el método de Lister se fue modificando y la introducción de la esterilización dio paso a la asepsia que, junto con otros avances, como la introducción de guantes, primero de algodón y posteriormente de goma, así como gorro y mascarilla, permitieron modificar sustancialmente la práctica quirúrgica

In this paper we do a revision of obstetric antisepsis developed in the XIX century by O.W. Holmes and especially by I. Semmelweis. He did a fundamental contribution in controlling infections by introducing the washing of hands before the act of child bearing. This meant a definite advance in the fight against puerperal infection. J. Lister introduced the surgical antisepsis about two decades later. This also meant a significant advance in the development of surgery by reducing infections substantially and allowing surgical interventions hard to perform until then. By the end of the 19th century, Lister's method was modified and sterilization introduced. This gave way to antisepsis. The introduction of gloves- which were made out of cotton at first and of rubber later on - as well as surgical caps and masks, allowed substantial modifications to the surgical practice

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[reaction: see text] A shape-persistent, conjugated o-phenylene ethynylene cyclic trimer was prepared in one step from tetrasubstituted benzene monomer 4 in 86% isolated yield through precipitation-driven alkyne metathesis. The template-free, selective generation of the molecular triangle 5 is a thermodynamically favored process and under equilibrium control. A novel tetrameric macrocycle 7 was generated via scrambling metathesis between tricycle 5 and hexacycle 6 using this dynamic covalent chemistry.