Molecular diagnostics with electrochemical biosensors and arrays

Biosensors are self-contained analytical devices in which a bioreceptor is integrated with a transducer. The interaction between the bioreceptor and a target analyte generates a signal suitable for analytical purposes. In electrochemical biosensors, a change in the redox state of the biorecognition/analyte system generates a change in an electrochemical quantity which can be monitored by electroanalytical techniques. Electrochemical sensors can be miniaturized using ultramicroelectrodes and nanoelectrodes and their arrays as transducers. These devices are characterized by high specificity and sensitivity and improved detection limits. Biosensors can be used by non-specialist operators at the point of care. For the above reasons, within the frame of the Trans2care project, the Laboratory of Electrochemical Sensors of the University Ca’ Foscari of Venice will collaborate with the project partners to develop electrochemical sensors suitable for specific clinical needs

Long-term <i>hm</i>F2 trends in the Eurasian longitudinal sector from the ground-based ionosonde observations

International audienceThe method earlier used for the foF2 long-term trends analysis is applied to reveal hmF2 long-term trends at 27 ionosonde stations in the European and Asian longitudinal sectors. Observed M(3000)F2 data for the last 3 solar cycles are used to derive hmF2 trends. The majority of the studied stations show significant hmF2 linear trends with a confidence level of at least 95% for the period after 1965, with most of these trends being positive. No systematic variation of the trend magnitude with latitude is revealed, but some longitudinal effect does take place. The proposed geomagnetic storm concept to explain hmF2 long-term trends proceeds from a natural origin of the trends rather than an artificial one related to the thermosphere cooling due to the greenhouse effect

Reinforcement-matrix interactions and their consequences on the mechanical behavior of basalt fibers-cement composites

In order to prepare basalt fibers-reinforced cement-based mortars with higher compatibility between reinforcement and matrix, basalt fibers with new surface treatments (sizing) were studied looking for enhanced interaction at the interphase between basalt fibers and cement matrix. As-received, calcinated, activated and silanized (by three silane aqueous solutions: i) aminopropyltriethoxysilane, APTES; ii) ¿-aminopropylmethyldiethoxysilane, APDES and iii) a mixture APTES APDES 50% by weight) basalt fibers were dispersed in Portland cement matrix. Performances of the composites were evaluated by mechanical tests. Final correlation between the fibers surface characteristics and mechanical performance was carried out considering the induced microstructural changes and adhesion at the interface. Fractographic analysis by SEM and laser and optical profilometry were performed. A clear improvement in mechanical properties was obtained when basalt fibers were dispersed in cement matrix. Results suggest that better behavior is achieved when basalt fibers modified with a complex mixture of silanes are dispersed in cement matrix.This work was financially supported by the Projects MAT2014-59116-C2 (Ministerio de Economía y Competitividad); 2012/00130/004 (Fondos de Investigación de Fco. Javier GonzalezBenito, política de reinversión de costes generales, Universidad Carlos III de Madrid) and 2011/00287/002 (Acción Estratégica en Materiales Compuestos Poliméricos e Interfases, Universidad Carlos III de Madrid). The research was financially supported also by the Project Bando per il Finanzia- mento di Progetti di Ricerca Congiunti per la Mobilit`a all Estero di Studenti di Dottorato prot. n 0051266 (Universit`a degli Studi di Roma, La Sapienza) in the frame the PhD Thesis of Morena Iorio. Finally, the authors would like to thank the group In-service Material Performance (Universidad Carlos III de Madrid) for supporting the project in the mechanical tests

Worst cases for an one-hop high frequency link

The characterisation of a HF channel by means of monthly electron density profiles can be complemented with a detailed study of radio propagation «worst cases» on situations with extremes conditions of radiopropagation for a given period. These «worst cases» correspond to conditions that can be identified by means of cumulative distributions of the key parameter f0F2. In this paper, the main parameters of the HF channel: time delay, apogee, elevation angle and transmission frequency with mean and extreme conditions are analysed. The method used to characterise the ionospheric channel is based on ray-tracing techniques

Experimental Characterization of Real Driving Cycles in a Light-Duty Diesel Engine under Different Dynamic Conditions

[EN] This paper studies the behavior of a Euro 6 diesel engine tested under dynamic conditions corresponding to different real driving emissions (RDE) scenarios. RDE cycles have been performed in an engine test bench by simulating its operation in a long van application. A computer tool has been designed to define the cycle accounting for different dynamic characteristics and driver behaviors to study their influence on CO2 and pollutant emissions, particularly CO, THC, and NOX. Different dynamic parameters have been established in terms of power, torque, engine speed, or vehicle speed. Additionally, a tool to estimate the emission of an RDE cycle from steady-state maps has been developed, helping to identify emission trends in a clearer way. Finally, the conclusions suggest that driving patterns characterized by lower engine speeds lead to fewer emissions. In addition, the analysis of RDE cycles from stationary maps helps to estimate the final tailpipe emissions of CO2 and NOX, offering the possibility to rely on tests carried out on engine test bench, dynamometer, or on the road.FundingThis research has been supported by Grant PID2020-114289RB-I00 funded by MCIN/AEI/10.13039/501100011033.Luján, JM.; Piqueras, P.; De La Morena, J.; Redondo-Puelles, F. (2022). Experimental Characterization of Real Driving Cycles in a Light-Duty Diesel Engine under Different Dynamic Conditions. Applied Sciences. 12(5):1-20. https://doi.org/10.3390/app1205247212012

Tight Regulation of Mechanotransducer Proteins Distinguishes the Response of Adult Multipotent Mesenchymal Cells on PBCE-Derivative Polymer Films with Different Hydrophilicity and Stiffness

: Mechanotransduction is a molecular process by which cells translate physical stimuli exerted by the external environment into biochemical pathways to orchestrate the cellular shape and function. Even with the advancements in the field, the molecular events leading to the signal cascade are still unclear. The current biotechnology of tissue engineering offers the opportunity to study in vitro the effect of the physical stimuli exerted by biomaterial on stem cells and the mechanotransduction pathway involved in the process. Here, we cultured multipotent human mesenchymal/stromal cells (hMSCs) isolated from bone marrow (hBM-MSCs) and adipose tissue (hASCs) on films of poly(butylene 1,4-cyclohexane dicarboxylate) (PBCE) and a PBCE-based copolymer containing 50 mol% of butylene diglycolate co-units (BDG50), to intentionally tune the surface hydrophilicity and the stiffness (PBCE = 560 Mpa; BDG50 = 94 MPa). We demonstrated the activated distinctive mechanotransduction pathways, resulting in the acquisition of an elongated shape in hBM-MSCs on the BDG50 film and in maintaining the canonical morphology on the PBCE film. Notably, hASCs acquired a new, elongated morphology on both the PBCE and BDG50 films. We found that these events were mainly due to the differences in the expression of Cofilin1, Vimentin, Filamin A, and Talin, which established highly sensitive machinery by which, rather than hASCs, hBM-MSCs distinguished PBCE from BDG50 films

Numerical analysis of flow characteristics in diesel injectors nozzles with convergent-divergent orifices

[EN] The geometry of diesel injector nozzles is known to significantly affect the characteristic spray behavior and emissions formation. In this paper, a novel nozzle concept, consisting of orifices with a convergent-divergent shape, is investigated through Computational Fluid Dynamics techniques. Three of these nozzles, characterized by different degrees of conicity, are compared to a nozzle with cylindrical orifices, which acts as a baseline. A homogeneous equilibrium model, validated against experimental data in previous works by the authors, is used to calculate the eventual cavitation formation inside these orifices. Additionally, the characteristics of the flow at the orifice outlet are analyzed for the four aforementioned nozzles in terms of their steady-state mass flow, effective outlet velocity and area coefficient. The results show that convergent-divergent nozzles exhibit a high cavitation intensity, located in the transition between the convergent and the divergent sections. This high cavitation intensity tends to compensate for the expected velocity decrease induced by the divergent shape, producing effective velocity values similar to those achieved by the cylindrical nozzle in many of the simulated conditions. The characteristics of the flow, together with the higher spray opening angles expected due to the divergent section of the nozzle, may improve atomization and fuel-air mixing processes.The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This work was supported by the Ministerio de Economia y Competitividad, of the Spanish Government, Project 'Estudio de la interaccion chorro-pared en condiciones realistas de motor' (Grant Number TRA2015-67679-c2-1-R). The PhD studies of David Jaramillo have been funded by "Conselleria d'Educacio Cultura i Esports" of "Generalitat Valenciana", Spain, by means of "Programa Vali+d per a personal investigador en formacio" (reference ACIF/2015/040).Salvador, FJ.; De La Morena, J.; Carreres, M.; Jaramillo-Císcar, D. (2017). Numerical analysis of flow characteristics in diesel injectors nozzles with convergent-divergent orifices. Proceedings of the Institution of Mechanical Engineers Part D Journal of Automobile Engineering. 231(14):1935-1944. https://doi.org/10.1177/0954407017692220S193519442311

Proteomics in drug hypersensitivity

21 p.-4 fig.-1 tab.Drug hypersensitivity reactions result from the activation of the immune system by drugs or their metabolites. The clinical presentations of drug hypersensitivity can range from relatively mild local manifestations to severe systemic syndromes that can be life-threatening. As in other allergic reactions, the causes are multifactorial as genetic, metabolic and concomitant factors may influence the occurrence of drug hypersensitivity. Formation of drug protein adducts is considered a key step in drug adverse reactions, and in particular in the immunological recognition in drug hypersensitivity reactions. Nevertheless, non-covalent interactions of drugs with receptors in immune cells or with MHC clefts and/or exposed peptides can also play an important role. In recent years, development of proteomic approaches has allowed the identification and characterization of the protein targets for modification by drugs in vivo and in vitro, the nature of peptides exposed on MHC molecules, the changes in protein levels induced by drug treatment, and the concomitant modifications induced by danger signals, thus providing insight into context factors. Nevertheless, given the complexity and multifactorial nature of drug hypersensitivity reactions, understanding the underlying mechanisms also requires the integration of knowledge from genomic, metabolomic and clinical studies.This work has been supported by grants SAF2012-36519 and SAF2015-68590R from MINECO/FEDER and RETIC RD12/0013/0008 from ISCIII to D.P.-S., and by RETIC RD12/0013/0001 and CP15/00103 from ISCIII, and PI-0699-2011 and PI-0179-2014 from Junta de Andalucía to M.I.M.Peer reviewe