Evaluating the reliability of NAND multiplexing with PRISM

Probabilistic-model checking is a formal verification technique for analyzing the reliability and performance of systems exhibiting stochastic behavior. In this paper, we demonstrate the applicability of this approach and, in particular, the probabilistic-model-checking tool PRISM to the evaluation of reliability and redundancy of defect-tolerant systems in the field of computer-aided design. We illustrate the technique with an example due to von Neumann, namely NAND multiplexing. We show how, having constructed a model of a defect-tolerant system incorporating probabilistic assumptions about its defects, it is straightforward to compute a range of reliability measures and investigate how they are affected by slight variations in the behavior of the system. This allows a designer to evaluate, for example, the tradeoff between redundancy and reliability in the design. We also highlight errors in analytically computed reliability bounds, recently published for the same case study

Semiconductor-metal core-shell nanostructures by colloidal heterocoagulation in aqueous medium

In contrast to complex syntheses for the preparation of colloidal nanocomposites in a core-shell structure proposed in the literature, we present herein a facile colloidal route based on a heterocoagulation process promoted by the electrostatic interaction among ceramic NiO nanoplatelets and metallic Ni nanoparticles (NPs). Before the heterocoagulation process, NiO and Ni were synthetized separately in presence of ultrasound, by chemical precipitation and chemical reduction of the same nickel precursor, respectively. After that, NiO-Ni core-shell nanostructures were prepared forcing the electrostatic interaction among surfaces in aqueous medium. The surface charge balances of both types of particles were tuned effectively by adjusting the pH in a free-additives suspension. For the surface modification of NiO by Ni, the ceramic suspensions maintain a positive zeta potential at pH 9, while the surface of metallic particles is negatively charged. Then the uniform coating of NiO platelets, by the electrostatically induced coagulation with Ni NPs, was favors. The degree of coverage and the formation of NiO-Ni core-shell nanostructures were followed referring the evolution of zeta potential with the geometric calculation in terms of size and morphology of both nanoparticles, and then corroborated by field emission scanning electron microscopy (FESEM).The authors acknowledge the support of the projects S2013/MIT-2862 and MAT2012–38650-02–01, MAT2012–38650-C02–02. M. de Dios acknowledges MINECO through the grant FPI-2013 and Dr. Z González acknowledges to MINECO through the grant PTQ-13–05985

Study of the expression of ecfG1 and ecfG2, two extracytoplasmic function sigma factors (ECFs) in Sphingopyxis granuli estirpe TFA

Motivation: In bacteria, the initiation of transcription requires a specific multi-domain subunits of RNA polymerase (RNAP) called sigma (σ) factors that binds to its core that play critical roles, including the recognition and opening of promoters for the RNA synthesis (Paget, 2015). One type of sigma factors are extracytoplasmic function sigma factors (ECF) which provide a means of regulating gene expression in response to a wide range of environmental changes (Feklistov et al., 2014). Sphingopyxis granuli TFA is a Gram-negative Alphaproteobacteria that is one of the few strains able to grow on the organic solvent tetralin as a sole carbon and energy source and able to grow respiring nitrate under anaerobic conditions (Gonzalez-Flores et al., 2016). In Sphingopyxis granuli TFA two ECF σ factors have been described, EcfG1 and EcfG2, that have a critcal biological role in the General Stress Response (GSR) in this bacterium (de Dios et al., 2020)Methods: With the aim of studying the transcriptional and postranscriptional regulation of each ecfG genes, a recombinant protein was built in which each EcfG have a FLAG-tag fused which allowed us to quantified the amount of each sigma factor by Western Blot studies in different growth conditions. This protein was constructed using a DNA-recombination method based on a double-strand break caused by SceI nuclease. Flanking regions of each ecfG genes were cloned in a multiple cloning site (MCS) of a non-replicative vector, this MCS is flanked by two SceI target sites. When this integrative vector is integrated into the chromosome of TFA, a broad host range vector including SceI gene downstream of an inducible promoter must be introduced and a double-strand break is caused in the chromosome. The final repair of this break results with a high frequency in the deletion of the target gene (ecfG). Thus we only get the gene with the FLAG-tagResults: In this work we analyzed the levels of expression of each sigma factors both at the transcriptional by RNA-seq and at translational level by quantifying the levels of each protein through Western Blot studies under different growth condition

Chemical precipitation of nickel nanoparticles on Ti(C,N) suspensions focused on cermet processing

Ti(C,N)-based cermets are currently used in high speed cutting tools industry due to its high thermal stability. In previous works, Fe was proposed as metal matrix, however the use of iron as continuous matrix strongly affects the processing due to the low wetting capability of molten Fe with the reinforcement phase, Ti(C,N). To solve this problem, the use of alloys such as FeNi has been proposed, where Ni improves the wettability between the ceramic and the metal phases. This work proposes a bottom-up approach to build the cermet microstructure through the synthesis of metal nanoparticles (NPs) on the surface of Ti(C,N) micrometric particles, creating Ti(C,N)-Ni core-shell structures. For that purpose, the in-situ synthesis of Ni NPs through the chemical reduction of a Ni precursor onto the surface of micrometric Ti(C,N) particles, previously stabilized in an aqueous suspension, was proposed. Core-shell structures were characterized by X-Ray Diffraction (XRD), scanning electron microscopy (SEM), field emission scanning electron microscopy (FE-SEM), scanning transmission electron microscopy (STEM), high resolution scanning electron microscopy (HRTEM), energy-dispersive X-Ray spectroscopy (EDX) and Raman Spectroscopy.The authors acknowledge the support of the projects S2013/MIT 2862 MAT2015 70780 C4 1 P and MAT2015 70780 C4 2 P. M. De Dios acknowledges MINECO through the grant BES 2013 065760 and Dr. Z González acknowledges to MINECO through the grant PTQ 13 05985

Ti(C,N)-Fe/Ni/FeNi core-shell structures for cermets processing

Proceedings of : The World PM2016 Congress & Exhibition, Hamburg, Germany, 9-13 October 2016This work proposes an alternative bottom-up approach to build cermet microstructures through the synthesis of metal hydroxide nanoparticles (NPs) on the surface of Ti(C,N) micrometric particles, creating core-shell Ti(C,N)-Ni(OH)2 and Ti(C,N)-FeO(OH) and their subsequent calcination cycle. This calcination cycle will help us to obtain Ti(C,N)- based cermets with fine microstructure and low amount of metal binder avoiding mechanical milling, the risks of handling nanoparticles, as well as overcoming the lack of availability and the high prices of those metal nanoparticles. The obtained structures were characterized by differential thermal analysis (DTA), thermogravimetry (TG), X-Ray Diffraction (XRD) and field emission scanning electron microscopy (FE-SEM) and energy-dispersive X-Ray spectroscopy (EDX).The authors acknowledge the support of the projects S2013/MIT-2862, MAT2012-38650-C02-01, MAT2012-38650-C02-02 and MAT2015-70780-C4-1-P. M. Dios acknowledges MINECO through the grant BES-2013-065760 and Dr. Z Gonzalez acknowledges to MINECO through the grant PTQ-13-0598

Interface study for the design of alternative matrixes in cermets

Proceedings of: European Congress and Exhibition on Powder Metallurgy (Euro PM2015 Congress & Exhibition), Reims (France), 4-7 September 2015.Liquid Phase Sintering (LPS) is used in the fabrication of hard materials and cermets which are difficult to densify by other approaches. During this process the melting point of the metal matrix is reached and the solid reinforcement is soluble in it. Thereby, via rearrangement and solucion-reprecipitation mechanism, these composite materials are sintered obtaining hihg density, hardness and wear resistance.For this sintering mechanism it is very important to know the solubility and wetting behaviour at high temperature of the metallic matrix and the reinforcement. In recent years one of the research topics in the field of hard materials is the search for new metallic matrixes so it becomes mandatory to study its interaction with the reinforcement from the viewpoint of solibility and wettability. This work shows a study combination of simulation tools and experimental testing of contacta angle mesurement at high temperature of the system Ni/TiCN because Ni is the conventional metallic matrix used in cermets and it is compared with the systems Fe/TiCN and Fe-15Ni/TiCN because the Fe is the main candidate for an alternative metallic matrix.The authors would like to acknowledge the financial support from the Spanish Government through the project MAT2012-38650-C02-01, the Regional Government of Madrid through the program MULTIMAT-CHALLENGE, ref. S2013/MIT-2862

Equilibrio líquido-vapor isotermo de mezclas de ésteres provenientes de la biomasa y alcoholes.

En este Trabajo de Fin de Grado se expone un estudio equilibrio líquido-vapor isotermo a dos temperaturas (303,15 y 323,15) K e isobárico a dos presiones (40,000 y 101,325 kPa) de mezclas de ésteres procedentes de la biomasa, concretamente, el butirato de etilo y alcoholes de cadena corta, en nuestro caso el metanol y el etanol.<br /

Novel colloidal approach for the microstructural improvement in Ti(C,N)/FeNi cermets

In this work, the combination of colloidal and powder metallurgy techniques was proposed as an alternative route to produce Ti(C,N)-based cermets with a 15-20 vol% of Fe/Ni alloy (85/15 wt%) as metal matrix. The novelty of this processing route is based in the mixture of fine powders (1;-3 µm) in suspension which promotes the uniformity of the phase distribution and consequently its reactivity, leading to 99.9% dense cermets with 1300 Vickers Hardness (HV30). The preparation of colloidal and chemically stable slurries of non-oxide and metal powders in aqueous media is a key step of the process. Highly concentrated aqueous slurries of Ti(C,N), Fe, Ni and C powders were prepared and mixed. Then bulk pieces were shaped by Slip casting (SC), Slip Casting + Cold Isostatic Pressing (SC-CIP) and Spray-Dry + Uniaxial Pressing of the obtained spherical granules (SDP). The composite formulation and the thermal treatment were optimized to prevent Ni sublimation during sintering as well as to improve liquid phase sintering in terms of wetting and reactivity among well packed particles. The effective dispersion of the slurry and the synergistic effect of combined techniques yielded the preparation of reliable materials by the SDP process with 15 wt% of FeNi with the addition of 0.5 wt% of C. The optimization of the composite formulation and the processing parameters improves both density and hardness of a finer microstructure of the composite after a short sintering treatment (120 min) at 1450 °C in vacuum.The authors acknowledge the financial support from the Spanish Government through the projects MAT2015-70780-C4-1-P and MAT2015-70780-C4-2-P, and the Regional Government of Madrid through the program MULTIMAT CHALLENGE, ref. S2013/MIT-2862. M. Dios acknowledges MINECO through the grant BES-2013-06576

E-cadherin expression is associated with somatostatin analogue response in acromegaly

Acromegaly is a rare disease resulting from hypersecretion of growth hormone (GH) and insulin‐like growth factor 1 (IGF1) typically caused by pituitary adenomas, which is associated with increased mortality and morbidity. Somatostatin analogues (SSAs) represent the primary medical therapy for acromegaly and are currently used as first‐line treatment or as second‐line therapy after unsuccessful pituitary surgery. However, a considerable proportion of patients do not adequately respond to SSAs treatment, and therefore, there is an urgent need to identify biomarkers predictors of response to SSAs. The aim of this study was to examine E‐cadherin expression by immunohistochemistry in fifty‐five GH‐producing pituitary tumours and determine the potential association with response to SSAs as well as other clinical and histopathological features. Acromegaly patients with tumours expressing low E‐cadherin levels exhibit a worse response to SSAs. E‐cadherin levels are associated with GH‐producing tumour histological subtypes. Our results indicate that the immunohistochemical detection of E‐cadherin might be useful in categorizing acromegaly patients based on the response to SSAs.ISCIII‐Subdirección General de Evaluación y Fomento de la Investigación PI13/02043 PI16/00175FEDER PI13/02043 PI16/00175Junta de Andalucía A‐0023‐2015 A‐0003‐2016 CTS‐1406 BIO‐0139Andalusian Ministry of Health C‐0015‐2014CIBERobn PI13/ 02043 PI16/0017