El espacio en las Sintesi de Marinetti.

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Synchronous neoplastic lesions in colorectal cancer. An analysis of possible risk factors favouring presentation

Aim: few data have been published regarding the causes of synchronous lesions in patients with colorectal cancer. The aim of our study was to identify potential factors that might be implicated in the development of multicentric lesions, since this knowledge could be useful for tailored follow-up once initial synchronous lesions have been removed. Methods: we retrospectively reviewed 382 colorectal cancer cases diagnosed by total colonoscopy and histological study of surgical specimens. We divided our population into 2 groups, based on whether they had synchronous lesions or otherwise. Several data related to personal and family history, habits, symptoms, and tumor characteristics were assessed. Univariate and multivariate statistical analyses were performed. Results: 208 (54.5%) patients had synchronous adenomas and 28 (7.3%) had synchronous cancer. A multivariate analysis showed that the following parameters were consistently related to the presence of multicentric lesions –male gender: OR = 1.97; CI = 1.13-3.45; p = 0.017; age ≥ 59 years: OR = 2.57; CI = 1.54-4.29; p < 0.001; personal history of colonic adenomas: OR = 3.04; CI = 1.04-8.85; p = 0.042; and obstructive tumors: OR = 0.48; CI = 0.27-0.85; p = 0.012. Conclusion: our results show that several parameters that are easy to measure could be considered risk factors for the development of multicentric lesions. These factors need to be confirmed with follow-up studies analyzing their role in patients with and without metachronic lesions once all synchronous lesions have been removed

Detection of a new community genotype methicillin-resistant staphylococcus aureus clone that is unrelated to the USA300 clone and that causes pediatric infections in colombia

The dissemination of a clone of community genotype methicillin-resistant Staphylococcus aureus (CG-MRSA) that is related to USA300 has been reported in Latin America. We recently detected isolates of a new clone of CG-MRSA (spa type t1635 and ACME-negative) that was genetically unrelated to the USA300 clone and that causes infections in children in Colombia. This finding indicates the appearance of a new clone of CG-MRSA in our region. Copyright © 2013, American Society for Microbiology

Author Correction: Tree mode of death and mortality risk factors across Amazon forests (Nature Communications, (2020), 11, 1, (5515), 10.1038/s41467-020-18996-3)

The original version of this Article contained an error in Table 2, where the number of individuals in the “All Amazonia” row was reported as 11,6431 instead of 116,431. Also, the original version of this Article contained an error in the Methods, where the R2 for the proportion of broken/uprooted dead trees increase per year was reported as 0.12, the correct value being 0.06. The original version of this Article contained errors in the author affiliations. The affiliation of Gerardo A. Aymard C. with UNELLEZGuanare, Herbario Universitario (PORT), Portuguesa, Venezuela Compensation International Progress S.A. Ciprogress–Greenlife

Determinación de clorpirifos en leche mediante el uso de un biosensor amperométrico

RESUMEN: El clorpirifos es un insecticida comercial organofosforado, en Colombia su uso abarca diferentes cultivos de pastizales y sitios urbanos. El clorpirifos funciona como un inhibidor de la enzima acetilcolinesterasa, tanto en insectos como en mamíferos, afectando directamente al sistema nervioso central. En los rebaños lecheros el uso inadecuado del clorpirifos puede producir leche con residuos de pesticidas. Según la Organización Mundial de la Salud, el límite de concentración permitido de clorpirifos en la leche de vaca es de 0,02 mg / L. Este trabajo explora el uso de un biosensor amperométrico enzimático como herramienta capaz de determinar la presencia de clorpirifos en la leche de vaca, trabajando en paralelo con la técnica analítica de cromatografía de gases. La enzima acetilcolinesterasa fue utilizada como elemento biológico e inmovilizada sobre electrodos de diferentes materiales de tipo "screen printed" a través del método de "cross linking". Se determinaron las constantes cinéticas de la enzima libre y de la enzima inmovilizada. Se desarrolló un prototipo que permite mediciones de Voltametría en sensor impreso, con características de bajo costo, portabilidad y fácil manejo, dicho prototipo fué utilizado para la cuantificación de la señal bioquímica producida en la reacción enzimática dada sobre el electrodo previamente inmovilizado y utilizada en las pruebas de inhibición y optimización del biosensor. La validación de la técnica para la detección de clorpirifos mediante cromatografía de gases arrojó como resultado que esta técnica analítica cumple los criterios de linealidad, precisión, exactitud y especificidad para la cuantificación de valores traza de 10 μg / L a 100 μg / L con la presencia de un efecto matriz. Se concluye que el biosensor puede servir como técnica cualitativa para la detección de plaguicidas en leche pero no cuantitativa, por lo que los biosensores pueden ser herramientas capaces de detectar la presencia de clorpirifos en leche en tiempo real, permitiendo rechazar en el mismo hato lechero, leches que tienen presencia de clorpirifos y para la cuantificación se puede utilizar una técnica más robusta como la cromatografía de gases

Representación que los accionistas del Banco Nacional de San Carlos reunidos en Junta General hacen a las Cortes con motivo de las resoluciones de 18, 26 y 29 de mayo último, manifestando los medios que han adoptado para conciliar la obediencia a las decisiones del Congreso con sus derechos de propiedad ...

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El espacio en las Sintesi de Marinetti.

Sin resume

Nutrients Cycle within Swine Production: Generation, Characteristics, Treatment and Revaluation

The swine production generates slurries nutrients rich, which could be revaluated in cereal crops used for its food and energy generation (biogas) for use on the farm. However, the revaluation requires to know their physical–chemical and biological characteristics, which allow giving an adequate transformation (treatment). On the one hand, swine production and consumption market reveal the superiority of emergent countries on meat/cereal (feed) production and swine meat consumption (concentrated population). The food composition and growth phase will influence the swine slurries composition, which is rich in organic matter, macronutrients (N, P) and micronutrients (Cu and Zn). These characteristics will generate odors (organic matter, macronutrients) and ecotoxicology effects (macro/micronutrients) if they are not treated. Moreover, the swine slurries treatment allows revaluated them in agriculture and obtaining energy. Anaerobic technologies (anaerobic lagoon, mixed complete reactors, UASB, among others) are the most used/cost-effective to organic matter removal from swine slurries, obtaining from 0.28 to 0.83 m3 biogas/kg organic matter. Meanwhile, passive technologies (constructed wetlands) are the most used technologies to nutrients and metals removal. Treated swine slurries from constructed wetlands have agronomic properties. Therefore, the nutrients cycle within swine production would favor concepts of revaluation in origin

Degradation of polycyclic aromatic hydrocarbons in water: Alternative treatments to conventional processes.

Nowadays, polycyclic aromatic hydrocarbons (PAHs) are a group of chemical substances that deserves a great attention. PAHs consist of two or more condensed benzene rings, bonded in linear, cluster or angular arrangements that are ubiquitous in the environment. Due to their low solubility and high affinity for particulate matter, PAHs are found in water in extreme low concentrations, in the range of ng L-1 or µg L-1. However, even at these ultra-trace or trace levels, they exhibit harmful effects on living beings and humans, especially when present as mixtures. That is the case of anthracene (AN), which has been reported as an acute phototoxic compound, and benzo[a]pyrene (BaP), which is a carcinogenic and mutagenic pollutant. Therefore, their presence in the environment and, specifically in aquatic resources must be monitored. For this purpose, the chromatographic behavior of AN and BaP was studied, and three models were found describing the identification of AN and BaP, the quantification of AN and that of BaP. The factors influencing each of the models or indexes were also optimized and a new and fast analytical method allowing the determination of the analytes of interest at ultra-trace concentrations in surface water samples was developed. In addition to monitor the target pollutants, they must be also eliminated from water because of the adverse health effects associated. However, conventional processes water treatment facilities are operating with are not efficient in tackling the problem of AN and BaP pollution in water. In this regard, the implementation of alternative treatments, including advanced oxidation processes (AOPs), provides a very attractive option. AOPs have demonstrated to be highly interesting technologies for water remediation, particularly the combination of ultraviolet radiation in the UV-C range (UV-C) and hydrogen peroxide (H2O2). This Thesis addresses the evaluation of the efficiency of the UV-C/H2O2 oxidation system to treat water sampled from a natural reservoir polluted with AN and BaP. For this purpose, initially, the removal profiles of AN and BaP were investigated, as well as the organic matter mineralization capacity of the oxidation system and the production of innocuous degradation by-products. The system allowed obtaining very positive results in terms of the degradation of the pollutants of interest and the organic matter mineralization, avoiding the production of dangerous reactive intermediates. Furthermore, after the application of this treatment process, a residual H2O2 was observed in the reaction solution, which can be used for additional microbial load removal. The residual H2O2 found within the bulk after the application of the oxidation treatment was analyzed using an analytical method proposed here. Moreover, the oxidation potential of the UV-C/H2O2 process was assessed for the inactivation of wild total coliforms naturally contained in the water of study and the results were compared with the findings obtained from other photochemical technologies based on sonochemical reactions. It was found that the technology achieving the highest microorganism elimination in the shortest time and with the lowest electrical costs results was the UV-C/H2O2 process. Nevertheless, in spite of that, it is worth noting that the implementation of the UV-C/H2O2 oxidation process still requires high electrical needs, which increases the operating costs of the process. Therefore, in order to reduce such as costs, a photovoltaic (PV) array was sized and installed for supplying the energy requirements of the selected water treatment system. The installed PV system allows for the use of renewable energy both in developing and non-developing countries. In this regard, the treatment of water to be drinkable was observed to be plausible in countries with lack of economical resources and in communities far from the electrical grid, which exist in a high number in countries such as Colombia. In the second stage of the research, and taking into account the necessity of having kinetic models for finding out the optimal operating conditions without the necessity of conducting extensive experimentation, a kinetic model for the performance of the UV-C/H2O2 oxidation process was constructed and validated using a model compound. The kinetic model allows calculating the optimal level of H2O2 for efficiently degrading the pollutant of interest, as well as the effective level of HO• to be maintained throughout the reaction time of the UV-C/H2O2 system for achieving an efficient pollutant degradation, contributing to save costs and time.Ingeniería, Industria y Construcció