Macro- and micro- properties of multi-recycled aggregate concrete

ABSTRACT: In a future scenario in which all the concrete is recycled concrete, it will be necessary to recycle the recycled concrete. However, it is known that the recycling of concrete implies a loss of properties. This paper shows an innovative technique, the computerized microtomograph, used to evaluate closed porosity, volume of limestone aggregate fraction and volume of mortar of the multi-recycled aggregate concrete, in order to answer the question: how many times it is possible to recycle concrete? First, the source concrete mix using limestone coarse and fine aggregates was characterized. This mix was crushed to obtain a recycled aggregate that was used to manufacture the 1st generation or current recycled aggregate concrete. After the characterization of this 1st generation concrete, and in the same way, a 2nd and a 3rd generation concrete were obtained and characterized, using recycled aggregates from the 1st and 2nd concrete generations respectively. The evaluation by computerized axial tomography allows to know how the successive recycled affect the properties of the concrete. The results show that it is possible to observe the distribution and quantify the aggregate, cement paste and closed porosity contents of the recycled aggregate concrete showing that 3rd generation recycled concrete shows almost twice as much mortar as 1st generation one and demonstrates that it is only possible to recycle the concrete a finite number of times

Multiple recycled aggregate properties analysed by X-ray microtomography

This paper presents a novel technique used to analyse the volume of adhered mortar to the recycled aggregate. A computerized microtomograph (?CT) device was used to evaluate the volume of the aggregate, the volume of natural aggregate and the volume of adhered mortar. To this end, a natural aggregate has been characterized, using the ?CT, with which a source concrete has been produced. Subsequently, the source concrete has been crushed to obtain a first cycle recycled aggregate. After the characterization of the first-generation of recycled aggregate, a new source concrete has been made with it to be subsequently crushed again obtaining a second-generation recycled aggregates. In the same way a third-generation recycled aggregate has been obtained and has been equally characterized. The results show that the compaction capacity of the aggregate is reduced after successive recycling. It has been possible to quantify how much the closed porosity of the recycled aggregate decreases with the number of times it is recycled. The loss of natural aggregate and increase of the volume of adhered mortar have also been evaluated using this technique.The Erasmus+Program, founded by the Staff Mobility for Teaching Program of the European Council 2016/217, between Instituto Superior Técnico - University of Lisbon and the LADICIM - University of Cantabria. CERIS and the Foundation for Science and Technology (FCT) for funding this research

¿Pueden los factores clínicopatológicos mejorar la predicción de metástasis en ganglios linfáticos no centinelas en pacientes con cáncer de mama?

Introduction: To determine whether clinicopathological characteristics can improve the prediction of metastasis to nonsentinel lymph nodes (NSLNs) over the use of only mRNA copy number in sentinel lymph node (SLN) biopsies. Methods: This was a retrospective, observational study that included a total of 824 patients with T1-3 breast cancer who had clinically negative, ultrasound-negative axilla without evidence of metastasis and who underwent one-step nucleic acid amplification in SLN biop-sies. Results: 118 required a complete axillary lymph node dissection (ALNhD). About 35.6% (42/118) had metastases to a NSLN, and 64.4% (76/118) had no metastasis to a NSLN. The ROC curve of the total tumor load (TTL) presented an area under the curve (AUC) of 0.651 (95%; CI: 0.552-0.751). The 7294 copies of CK19 mRNA were established as the optimal cutoff point, with sensitivity: 93%, specificity: 63%, positive predictive value: 44%, and negative predictive value: 91%. By as-sociating the clinicopathological parameters (multicentricity, pooled immunohistochemistry [IHC], and progesterone receptors), the AUC went up to 0.752 (95% CI: 0.663-0.841). Conclusions: Clinicopathological factors should be considered together with the total CK19 mRNA copy number (the TTL) of the SLNs to improve the predictive capacity of metastatic involvement of the NSLNs

Continuous ultrafiltration during extracorporeal circulation and its effect on lactatemia: A randomized controlled trial

Introduction. Hyperlactatemia occurs during or after extracorporeal circulation in the form of lactic acidosis, increasing the risk of postoperative complications and the mortality rate. The aim of this study was to evaluate whether continuous high-volume hemofiltration with volume replacement through a polyethersulfone filter during the extracorporeal circulation procedure decreases postoperative lactatemia and its consequences. ||Materials and methods. This was a randomized controlled trial. Patients were randomly divided into two groups of 32: with or without continuous high-volume hemofiltration through a polyethersulfone membrane. Five patients were excluded from each group during the study period. The sociodemographic characteristics, filter effects, and blood lactate levels at different times during the procedure were evaluated. Secondary endpoints were studied, such as the reduction in the intubation time and time spent in ICU. ||Results. Lactatemia measurements performed during the preoperative and intraoperative phases were not significantly different between the two groups. However, the blood lactate levels in the postoperative period and at 24 hours in the intensive care unit showed a significant reduction and a possible clinical benefit in the hemofiltered group. Following extracorporeal circulation, the mean lactate level was higher (difference: 0.77 mmol/L; CI 0.95: 0.01–1.53) in the nonhemofiltered group than in the hemofiltered group (p<0.05). This effect was greater at 24 hours (p = 0.019) in the nonhemofiltered group (difference: 1.06 mmol/L; CI 0.95: 0.18–1.93) than in the hemofiltered group. The reduction of lactatemia is associated with a reduction of inflammatory mediators and intubation time, with an improvement in liver function. || Conclusions. The use and control of continuous high-volume hemofiltration through a polyethersulfone membrane during heart-lung surgery could potencially prevent postoperative complications. The reduction of lactatemia implied a reduction in intubation time, a decrease in morbidity and mortality in the intensive care unit and a shorter hospital stay.14 páginas

Praziquantel–Clays as Accelerated Release Systems to Enhance the Low Solubility of the Drug

Praziquantel is an antiparasitic drug indicated for the treatment of the schistosomiasis disease. This drug has very low aqueous solubility, requiring high oral doses for its administration which gives rise to side effects, therapeutic noncompliance and the appearance of resistant forms of the parasite. Clay minerals, like sepiolite and montmorillonite, are innocuous, non-toxic, biocompatible and low-cost excipients. Additionally, clays have high adsorbent properties that allow them to encapsulate drugs in nanometric spaces present in the channels in the case of the sepiolite or between the layers in the case of the montmorillonite. The interactions between the drug and clay minerals are studied experimentally with the strategy for preparing interactions products in organic solvents (ethanol, acetonitrile and dichloromethane) so that the interaction will be more effective and will be enhanced the aqueous solubility of praziquantel. The results showed that in the interaction products, the drug interacted with both clay minerals, which produced the loss of the crystallinity of the drug demonstrated by different techniques. This led to a significant increase in the dissolution rate of the praziquantel in all the interaction products in the simulated gastrointestinal tract media, except for the praziquantel–montmorillonite product prepared in dichloromethane that presented a controlled release in acid medium. Moreover, in vitro cytotoxicity and cell cycle studies were performed in the interaction products prepared with ethanol. The interaction product with sepiolite was biocompatible with the HTC116 line cells, and it did not produce alterations in the cell cycle. However, interaction products with montmorillonite did not produce cell death, but they showed affectation and damage of cells in the cell cycle study at the highest concentration tested (20–100 µM). Therefore, the different organic solvents used are adequate for the improvement of the biopharmaceutical profile of praziquantel. Drug–clay interaction products, specifically with sepiolite, showed very promising results in which new accelerated oral release systems of the praziquantel were obtained.Ministerio de Ciencia e Innovacion government PCIN-2017-098 FIS2016-77692-C2-2-P CGL2016-80833-RJunta de Andalucia RNM1897 P18-RT-378

Durability Assessment of a Plasma-Polymerized Coating with Anti-Biofilm Activity against L. monocytogenes Subjected to Repeated Sanitization

Copyright: © 2021 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/).[EN] Biofilm formation on food-contact surfaces is a matter of major concern causing food safety and spoilage issues to this sector. The aim of this study was to assess the durability of the anti-biofilm capacity of a plasma-polymerized coating composed of a base coating of (3-aminopropyl) triethoxysilane (APTES) and a functional coating of acrylic acid (AcAc). Coated and uncoated AISI 316 stainless steel (SS) plates were subjected to five sanitization cycles with sodium hypochlorite (0.05%) and peracetic acid (0.5%). The effectiveness of the coating for the inhibition of multi-strain Listeria monocytogenes biofilm formation was confirmed using a three-strain cocktail, which was grown on the SS plates at 12◦ C for 6 days. Compared to the uncoated SS, relative biofilm productions of 14.6% on the non-sanitized coating, 27.9% on the coating after sanitization with sodium hypochlorite, and 82.3% on the coating after sanitization with peracetic acid were obtained. Morphological and physicochemical characterization of the coatings suggested that the greater anti-biofilm effectiveness after sanitization with sodium hypochlorite was due to the high pH of this solution, which caused a deprotonation of the carboxylic acid groups of the functional coating. This fact conferred it a strong hydrophilicity and negatively charged its surface, which was favorable for preventing bacterial attachment and biofilm formation.SIThis publication is based upon work from COST Action CA19110—PlAgri, supported by COST (European Cooperation in Science and Technology-www.cost.eu). XPS tests were conducted by the Advanced Microscopy Laboratory (LMA) of The Institute of Nanoscience of Aragón (INA), University of Zaragoza. The authors are thankful to the LMA-INA for the access to their equipment and their expertise. The AFM images were taken by the Central Research Support Service (SCAI) of the University of Málaga (UMA). The author P. Fernández-Gómez is grateful to Junta de Castilla y León and the European Social Fund (ESF) for awarding her a predoctoral grant (BOCYL-D-15122017-4). The author M. Oliveira is in receipt of a Juan de la Cierva contract IJC2018-035523-I awarded by the Spanish Ministry of Science, Innovation, and Universities MCIN/AEI/10.13039/501100011033. The author E. Sainz-García, as researcher of the University of La Rioja, is thankful to the postdoctoral training program funded by the Plan Propio of the University of La Rioja. The authors I. Muro-Fraguas and A. Sainz-García are thankful to the program of pre-doctoral contracts for the training of research staff that is funded by the University of La Rioja.This study is part of the Research, Development and Innovation projects AGL2017-82779- C2-R and PID2020-113658RB-C2, funded by MCIN/AEI/10.13039/501100011033 and by ERDF “A way to make Europe”