Antibacterial activity of bovine milk lactoferrin on the emerging foodborne pathogen Cronobacter sakazakii: Effect of media and heat treatment

Cronobacter sakazakii is a pathogen transmitted by food, with high osmotic resistance and tolerance to desiccation, which affects mainly to newborns, infants and immunocompromised adults. C. sakazakii infection in infants has been associated with consumption of powdered milk. The purpose of this study was to evaluate the antibacterial activity of native and iron-saturated bovine lactoferrin (bLF) (from 0.5 to 5 mg/ml) on non-desiccated and desiccated C. sakazakii (104 CFU/ml) in different media (phosphate buffer, bovine skim milk and whey). In general, native bLF was the only effective form that inhibited growth of C. sakazakii in all media, its activity increasing with concentration and time of incubation. These results suggest that the antibacterial effect of bLF on C. sakazakii is mainly due to iron sequestration. However, iron-saturated bLF showed some effect by reducing the viability of C. sakazakii in whey. There has not been observed an increased sensitivity of desiccated bacteria to native bLF in phosphate buffer. However, although the antibacterial activity of native bLF against non-desiccated C. sakazakii was drastically reduced in milk or whey compared to phosphate buffer, there was a certain activity when it was assayed against desiccated cells in those media. The effect of some heat treatments on the antibacterial activity of native bLF was evaluated and only those of 72 °C for 15 s, 85 °C for 15 s, and 63 °C for 30 min maintained its whole activity

Comparison of Different Parameters to Evaluate Delamination in Edge Trimming of Basalt Fiber Reinforced Plastics (BFRP)

[EN] Delamination is one of the main problems that occur when machining fiber-reinforced composite materials. In this work, Types I and II of delamination are studied separately in edge trimming of basalt fiber reinforced plastic (BFRP). For this purpose, one-dimensional and area delamination parameters are defined. One-dimensional parameters (Wa and Wb) allow to know average fibers length while the analysis of area delamination parameters (Sd) allow to evaluate delamination density. To study delamination, different tests are carried out modifying cutting parameters (cutting speed, feed per tooth and depth of cut) and material characteristics (fiber volume fraction and fiber orientation). Laminates with a lower fiber volume fraction do not present delamination. Attending to one-dimensional parameters it can be concluded that Type II delamination is more important than Type I and that a high depth of cut generates higher values of delamination parameters. An analysis of variance (ANOVA) is performed to study area parameters. Although delamination has a random nature, for each depth of cut, more influence variables in area delamination are firstly, feed per tooth and secondly, cutting speed.This research was funded by Government of Spain, grant number PID2019-108807RB-I00.Navarro-Mas, M.; Meseguer, M.; Lluch-Cerezo, J.; García Manrique, JA. (2020). Comparison of Different Parameters to Evaluate Delamination in Edge Trimming of Basalt Fiber Reinforced Plastics (BFRP). Materials. 13(23):1-17. https://doi.org/10.3390/ma13235326S1171323Lopresto, V., Caggiano, A., & Teti, R. (2016). High Performance Cutting of Fibre Reinforced Plastic Composite Materials. Procedia CIRP, 46, 71-82. doi:10.1016/j.procir.2016.05.079Ozkan, D., Panjan, P., Gok, M. S., & Karaoglanli, A. C. (2020). Experimental Study on Tool Wear and Delamination in Milling CFRPs with TiAlN- and TiN-Coated Tools. Coatings, 10(7), 623. doi:10.3390/coatings10070623Nguyen-Dinh, N., Bouvet, C., & Zitoune, R. (2019). Influence of machining damage generated during trimming of CFRP composite on the compressive strength. Journal of Composite Materials, 54(11), 1413-1430. doi:10.1177/0021998319883335Razfar, M. R., & Zadeh, M. R. Z. (2009). Optimum damage and surface roughness prediction in end milling glass fibre-reinforced plastics, using neural network and genetic algorithm. Proceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture, 223(6), 653-664. doi:10.1243/09544054jem1409Neeli, N., Jenarthanan, M. P., & Dileep Kumar, G. (2018). Multi-response optimization for machining GFRP composites using GRA and DFA. Multidiscipline Modeling in Materials and Structures, 14(3), 482-496. doi:10.1108/mmms-08-2017-0092Azmi, A. I., Lin, R. J. T., & Bhattacharyya, D. (2012). Machinability study of glass fibre-reinforced polymer composites during end milling. The International Journal of Advanced Manufacturing Technology, 64(1-4), 247-261. doi:10.1007/s00170-012-4006-6Jenarthanan, M. P., & Jeyapaul, R. (2018). Optimisation of machining parameters on milling of GFRP composites by desirability function analysis using Taguchi method. International Journal of Engineering, Science and Technology, 5(4), 22-36. doi:10.4314/ijest.v5i4.3Sreenivasulu, R. (2013). Optimization of Surface Roughness and Delamination Damage of GFRP Composite Material in End Milling Using Taguchi Design Method and Artificial Neural Network. Procedia Engineering, 64, 785-794. doi:10.1016/j.proeng.2013.09.154He, Y., Qing, H., Zhang, S., Wang, D., & Zhu, S. (2017). The cutting force and defect analysis in milling of carbon fiber-reinforced polymer (CFRP) composite. The International Journal of Advanced Manufacturing Technology, 93(5-8), 1829-1842. doi:10.1007/s00170-017-0613-6Raj, P. P., & Perumal, A. E. (2010). Taguchi Analysis of surface roughness and delamination associated with various cemented carbide K10 end mills in milling of GFRP. Journal of Engineering Science and Technology Review, 3(1), 58-64. doi:10.25103/jestr.031.11Hintze, W., Hartmann, D., & Schütte, C. (2011). Occurrence and propagation of delamination during the machining of carbon fibre reinforced plastics (CFRPs) – An experimental study. Composites Science and Technology, 71(15), 1719-1726. doi:10.1016/j.compscitech.2011.08.002Wang, F., Yin, J., Ma, J., Jia, Z., Yang, F., & Niu, B. (2017). Effects of cutting edge radius and fiber cutting angle on the cutting-induced surface damage in machining of unidirectional CFRP composite laminates. The International Journal of Advanced Manufacturing Technology, 91(9-12), 3107-3120. doi:10.1007/s00170-017-0023-9Li, M., Huang, M., Jiang, X., Kuo, C., & Yang, X. (2018). Study on burr occurrence and surface integrity during slot milling of multidirectional and plain woven CFRPs. The International Journal of Advanced Manufacturing Technology, 97(1-4), 163-173. doi:10.1007/s00170-018-1937-6Sheikh-Ahmad, J. Y., Dhuttargaon, M., & Cheraghi, H. (2017). New tool life criterion for delamination free milling of CFRP. The International Journal of Advanced Manufacturing Technology, 92(5-8), 2131-2143. doi:10.1007/s00170-017-0240-2Szwajka, K., & Trzepieciński, T. (2016). Effect of tool material on tool wear and delamination during machining of particleboard. Journal of Wood Science, 62(4), 305-315. doi:10.1007/s10086-016-1555-6Wang, F., Zhang, B., Jia, Z., Zhao, X., & Wang, Q. (2019). Structural optimization method of multitooth cutter for surface damages suppression in edge trimming of Carbon Fiber Reinforced Plastics. Journal of Manufacturing Processes, 46, 204-213. doi:10.1016/j.jmapro.2019.09.013Masek, P., Zeman, P., Kolar, P., & Holesovsky, F. (2018). Edge trimming of C/PPS plates. The International Journal of Advanced Manufacturing Technology, 101(1-4), 157-170. doi:10.1007/s00170-018-2857-1Dhand, V., Mittal, G., Rhee, K. Y., Park, S.-J., & Hui, D. (2015). A short review on basalt fiber reinforced polymer composites. Composites Part B: Engineering, 73, 166-180. doi:10.1016/j.compositesb.2014.12.011Navarro-Mas, M., García-Manrique, J., Meseguer, M., Ordeig, I., & Sánchez, A. (2018). Delamination Study in Edge Trimming of Basalt Fiber Reinforced Plastics (BFRP). Materials, 11(8), 1418. doi:10.3390/ma1108141

Tool wear study in edge trimming on basalt fibre reinforced plastics

[EN] In machining of reinforced fibre composite parts, abrasive fibres and material heterogeneity produce poor surface finish, delamination and tool wear. In this research, basalt fibre reinforced plastic is machined with edge trimming in order to study tool wear, using a tool holder of diameter 25 mm, with two exchangeable uncoated carbide cutting inserts. Cutting conditions (cutting speed, feed per tooth and depth) and material characteristics (fibre volume fraction and fibre orientation) are evaluated to know their influence in the flank wear (Vb) of the tool. An analysis of variance (ANOVA) was performed to study flank wear and material removal rate, and a generalized linear model (GLM) was developed. More influence variables in the flank wear are the machining conditions, being the tool life suitable for this machining and material.This work was funded by the Research Project DPI2013-44903-R-AR of the MINER.Navarro-Mas, M.; Meseguer, MD.; Sánchez Galdón, AI.; Gutiérrez, SC. (2017). Tool wear study in edge trimming on basalt fibre reinforced plastics. Procedia Manufacturing. 13:259-266. doi:10.1016/j.promfg.2017.09.067S2592661

Milling angular references and process parameters on fiber reinforced plastics

[EN] Machining of fiber-reinforced composites produces delamination in the workpiece. In bidirectional long fiber fabric reinforced composites, delamination depends on different parameters. In this work, two parameters are studied: fiber orientation angle respect to machining direction and the distance of the warp yarn from the trimmed edge until the next dip below the crossing fill. This work defines angles relating fiber orientation with cutting and feed movements and their relations in a robust way, being applied to edge trimming and grooving operations. On the other hand, for Type II delamination, three different kinds of delamination (constant, uniform pattern variation and random) are studied taking into account fiber orientation, wick size and the fiber orientation angle respect to machining direction.Navarro-Mas, M.; Meseguer, M.; Ordeig Fernández, IN.; Lluch-Cerezo, J. (2021). Milling angular references and process parameters on fiber reinforced plastics. IOP Conference Series Materials Science and Engineering. 1193:1-10. https://doi.org/10.1088/1757-899x/1193/1/012004110119

Detection of butyric spores by different approaches in raw milks from cow, ewe and goat

Clostridium tyrobutyricum is described as the main causative agent of late blowing defect in cheese. Currently, there are no fast methods to detect this microorganism in raw milk, which would allow determining the use of milk for fresh or cured cheese. The technique commonly used is the Most Probable Number, which is laborious and non-specific. In this work, we present the optimization of a real-time PCR-based detection method for C. tyrobutyricum spores in raw milk samples. This novel approach extracts DNA in a semi-automatic system with magnetic beads. The applicability of the developed procedure has been tested in field milk samples from cow, ewe and goat (n = 202), allowing detection of low levels of butyric spores. Raw milk samples were also analyzed by microbiological culture in a selective medium for butyric bacteria, and positive colonies were identified by multiplex PCR and 16S rDNA sequencing. Apart from C. tyrobutyricum, other Clostridium spp. were identified, which should be considered for further development of detection methods

Delamination Study in Edge Trimming of Basalt Fiber Reinforced Plastics (BFRP)

[EN] Although there are many machining studies of carbon and glass fiber reinforced plastics, delamination and tool wear of basalt fiber reinforced plastics (BFRP) in edge trimming has not yet studied. This paper presents an end milling study of BFRP fabricated by resin transfer molding (RTM), to evaluate delamination types at the top layer of the machined edge with different cutting conditions (cutting speed, feed rate and depth of cut) and fiber volume fraction (40% and 60%). This work quantifies delamination types, using a parameter Sd/L, that evaluates the delamination area (Sd) and the length (L), taking into account tool position in the yarn and movement of yarns during RTM process, which show the random nature of delamination. Delamination was present in all materials with 60% of fiber volume. High values of tool wear did not permit to machine the material due to an excessive delamination. Type II delamination was the most usual delamination type and depth of cut has influence on this type of delamination.The authors gratefully acknowledge the funding by the Ministerio de Educacion y Ciencia of the Spanish government under grant DPI2013-44903-R-AR.Navarro-Mas, M.; García Manrique, JA.; Meseguer, MD.; Ordeig Fernández, IN.; Sánchez Galdón, AI. (2018). Delamination Study in Edge Trimming of Basalt Fiber Reinforced Plastics (BFRP). Materials. 11(8). doi:10.3390/ma1108141811

Approximating the solution stochastic process of the random Cauchy one-dimensional heat model

[EN] This paper deals with the numerical solution of the random Cauchy one-dimensional heat model. We propose a random finite difference numerical scheme to construct numerical approximations to the solution stochastic process. We establish sufficient conditions in order to guarantee the consistency and stability of the proposed random numerical scheme.The theoretical results are illustrated by means of an example where reliable approximations of the mean and standard deviation to the solution stochastic process are given.This work has been partially supported by the Ministerio de Economía y Competitividad Grant MTM2013-41765-P. Ana Navarro Quiles acknowledges the doctorate scholarship granted by Programa de Ayudas de Investigación y Desarrollo (PAID), Universitat Politècnica de València. M. A. Sohaly is also indebted to Egypt Ministry of Higher Education, Cultural Affairs, for its financial support [mohe-casem (2016)].Navarro Quiles, A.; Romero, J.; Roselló, M.; Sohaly, M. (2016). Approximating the solution stochastic process of the random Cauchy one-dimensional heat model. Abstract and Applied Analysis. 2016:1-7. https://doi.org/10.1155/2016/5391368S172016Logan, J. D. (2004). Partial Differential Equations on Bounded Domains. Undergraduate Texts in Mathematics, 121-171. doi:10.1007/978-1-4419-8879-9_4Wang, J. (1994). A Model of Competitive Stock Trading Volume. Journal of Political Economy, 102(1), 127-168. doi:10.1086/261924Tsynkov, S. V. (1998). Numerical solution of problems on unbounded domains. A review. Applied Numerical Mathematics, 27(4), 465-532. doi:10.1016/s0168-9274(98)00025-7Koleva, M. N. (2006). Numerical Solution of the Heat Equation in Unbounded Domains Using Quasi-uniform Grids. Lecture Notes in Computer Science, 509-517. doi:10.1007/11666806_58Han, H., & Huang, Z. (2002). A class of artificial boundary conditions for heat equation in unbounded domains. Computers & Mathematics with Applications, 43(6-7), 889-900. doi:10.1016/s0898-1221(01)00329-7Wu, X., & Sun, Z.-Z. (2004). Convergence of difference scheme for heat equation in unbounded domains using artificial boundary conditions. Applied Numerical Mathematics, 50(2), 261-277. doi:10.1016/j.apnum.2004.01.001Cortés, J. C., Sevilla-Peris, P., & Jódar, L. (2005). Analytic-numerical approximating processes of diffusion equation with data uncertainty. Computers & Mathematics with Applications, 49(7-8), 1255-1266. doi:10.1016/j.camwa.2004.05.015Casabán, M.-C., Cortés, J.-C., García-Mora, B., & Jódar, L. (2013). Analytic-Numerical Solution of Random Boundary Value Heat Problems in a Semi-Infinite Bar. Abstract and Applied Analysis, 2013, 1-9. doi:10.1155/2013/676372Casabán, M.-C., Company, R., Cortés, J.-C., & Jódar, L. (2014). Solving the random diffusion model in an infinite medium: A mean square approach. Applied Mathematical Modelling, 38(24), 5922-5933. doi:10.1016/j.apm.2014.04.063Villafuerte, L., Braumann, C. A., Cortés, J.-C., & Jódar, L. (2010). Random differential operational calculus: Theory and applications. Computers & Mathematics with Applications, 59(1), 115-125. doi:10.1016/j.camwa.2009.08.061Øksendal, B. (2003). Stochastic Differential Equations. Universitext. doi:10.1007/978-3-642-14394-6Kloeden, P. E., & Platen, E. (1992). Numerical Solution of Stochastic Differential Equations. doi:10.1007/978-3-662-12616-5Holden, H., Øksendal, B., Ubøe, J., & Zhang, T. (2010). Stochastic Partial Differential Equations. doi:10.1007/978-0-387-89488-

Design, synthesis and structure-activity evaluation of novel 2-pyridone-based inhibitors of a-synuclein aggregation with potentially improved BBB permeability

The treatment of Parkinson''s disease (PD), the second most common neurodegenerative human disorder, continues to be symptomatic. Development of drugs able to stop or at least slowdown PD progression would benefit several million people worldwide. SynuClean-D is a low molecular weight 2-pyridone-based promising drug candidate that inhibits the aggregation of a-synuclein in human cultured cells and prevents degeneration of dopaminergic neurons in a Caenorhabditis elegans model of PD. Improving SynuClean-D pharmacokinetic/pharmacodynamic properties, performing structure/activity studies and testing its efficacy in mammalian models of PD requires the use of gr-amounts of the compound. However, not enough compound is on sale, and no synthetic route has been reported until now, which hampers the molecule progress towards clinical trials. To circumvent those problems, we describe here an efficient and economical route that enables the synthesis of SynuClean-D with good yields as well as the synthesis of SynuClean-D derivatives. Structure-activity comparison of the new compounds with SynuClean-D reveals the functional groups of the molecule that can be disposed of without activity loss and those that are crucial to interfere with a-synuclein aggregation. Several of the derivatives obtained retain the parent''s compound excellent in vitro anti-aggregative activity, without compromising its low toxicity. Computational predictions and preliminary testing indicate that the blood brain barrier (BBB) permeability of SynuClean-D is low. Importantly, several of the newly designed and obtained active derivatives are predicted to display good BBB permeability. The synthetic route developed here will facilitate their synthesis for BBB permeability determination and for efficacy testing in mammalian models of PD. © 2021 The Author

Alternative pathways to a sustainable future lead to contrasting biodiversity responses

Land-use change is currently the main driver of biodiversity loss. Projections of land-use change are often used to estimate potential impacts on biodiversity of future pathways of human development. However, such analyses frequently neglect that species can persist in human-modified habitats. Our aim was to estimate changes in biodiversity, considering affinities for multiple habitats, for three different land-use scenarios. Two scenarios focused on more sustainable trajectories of land-use change, based on either technological improvements (Pathway A) or societal changes (Pathway B), and the third reflected the historical or business-as-usual trends (Pathway 0). Using Portugal as a case study, we produced spatially-explicit projections of land-use change based on these pathways, and then we assessed the resulting changes in bird species richness and composition projected to occur by 2050 in each of the scenarios. By 2050, alpha and gamma diversity were projected to decrease, relative to 2010, in Pathway 0 and increase in Pathways A and B. However, different pathways favored different species groups, and presented strong regional differences. In the technological improvement pathway, loss of extensive agricultural areas led to an increase in both natural and extensive forest areas. In this pathway, forest species increase at the expense of farmland species, while in the societal change pathway the reverse occurs, as extensive agricultural areas were projected to increase. We show that while multiple positive pathways (A and B) for biodiversity can be envisioned, they will lead to differential impacts on biodiversity depending on the transformational changes in place and the regional socio-economic context. Our results suggest that considering compositional aspects of biodiversity can be critical in choosing the appropriate regional land-use policies

Influencia de la radioterapia sobre la reconstrucción mamaria inmediata posmastectomía ahorradora de piel. ¿Afecta igual antes que después?

Introducción La mastectomía bilateral con reconstrucción inmediata (MB + RMI) está aumentando. La radioterapia incrementa las complicaciones, pero se han ampliado los criterios de administración. Queremos evaluar las tasas de complicaciones/secuelas realizando un análisis comparativo con una cohorte sin radioterapia. Métodos Análisis observacional analítico de cohortes retrospectivo de pacientes tratadas mediante MB como tratamiento de cáncer de mama con RMI entre 2000 y 2016. Se evalúan 3 grupos: grupo 1: pacientes previamente tratadas con cirugía local y radioterapia, y MB + RMI posterior; grupo 2: pacientes con MB + RMI y radioterapia posterior por un cáncer de novo, y grupo 3: pacientes con MB + RMI sin radioterapia previa ni posterior. Evaluamos variables demográficas, técnicas quirúrgicas y morbilidad postoperatoria. Resultados Se intervinieron un total de 296 MB + RMI. Grupo 1: 125 pacientes con radioterapia previa, administrada 21, 69 meses antes de media. Tasa de complicaciones del 28, 8%, secuelas 33, 6% y reintervención 33, 6%. Grupo 2:71 pacientes con radioterapia tras reconstrucción 134, 2 días de media. Tasa de complicaciones del 29, 6%, secuelas 19, 9% y reintervención 16, 9%. Grupo 3: 100 pacientes. Tasa de complicaciones del 30%, secuelas 21% y reintervención 20%. Encontramos más secuelas en el grupo 1, con casi el doble de reintervenciones que en el grupo 2 (33, 6% vs. 16, 9%; p = 0, 067). Conclusiones La tasa de complicaciones a largo plazo y la tasa de reintervenciones es mayor en el grupo MB + RMI con radioterapia previa que en los grupos MB + RMI con radioterapia posterior o MB + RMI sin radioterapia. Introduction: The use of bilateral mastectomy with immediate reconstruction is increasing. Radiotherapy increases complications; however, its uses have been extended. We evaluate the profile of the complications and long-term failure of reconstruction through a comparative analysis with a cohort without radiotherapy. Methods: Retrospective analysis of patients with breast cancer who underwent mastectomy with immediate reconstruction during 2000-2016. Three groups were evaluated: 1) patients who received radiotherapy and posterior breast reconstruction; 2) patients with bilateral mastectomy and immediate reconstruction following adjuvant radiotherapy; 3) patients who did not receive radiotherapy at all. Demographic variables, surgical techniques and postoperative morbidity were assessed. Outcomes and complications were compared between cohorts. Analysis was done with SPSS Statistics. Results: 296 bilateral mastectomies with immediate reconstruction. Mean age 48.4 ± 9. No differences in comorbidity in the different groups. Group 1: 125 patients. Radiotherapy given 21.69 months before, on average. Complication rate: 20%. Failure of reconstruction rate: 20%. Reoperation rate: 33.6%. Group 2: 71 patients. Radiotherapy after reconstruction: mean 134.2 days. Complication rate: 36.7%. Failure of reconstruction rate: 21.1%. Reoperation rate: 16.9%. Group 3: 100 patients. Complication rate: 25%. Failure of reconstruction rate: 21%. Reoperation rate: 20%. Morbidity published in patients after radiotherapy before or after reconstruction is higher than complications in patients who did not receive radiotherapy. Even so, in our series they were similar. We found a higher sequelae rate in group 1, with almost double the rate of reoperation. Conclusions: Patients who underwent radiotherapy before reconstruction had a higher risk of developing failure of reconstruction and needing reoperation than those patients who received radiotherapy after breast reconstruction or did not receive radiotherapy at all