The Cellular Phenotype of Roberts Syndrome Fibroblasts as Revealed by Ectopic Expression of ESCO2

Cohesion between sister chromatids is essential for faithful chromosome segregation. In budding yeast, the acetyltransferase Eco1/Ctf7 establishes cohesion during DNA replication in S phase and in response to DNA double strand breaks in G2/M phase. In humans two Eco1 orthologs exist: ESCO1 and ESCO2. Both proteins are required for proper sister chromatid cohesion, but their exact function is unclear at present. Since ESCO2 has been identified as the gene defective in the rare autosomal recessive cohesinopathy Roberts syndrome (RBS), cells from RBS patients can be used to elucidate the role of ESCO2. We investigated for the first time RBS cells in comparison to isogenic controls that stably express V5- or GFP-tagged ESCO2. We show that the sister chromatid cohesion defect in the transfected cell lines is rescued and suggest that ESCO2 is regulated by proteasomal degradation in a cell cycle-dependent manner. In comparison to the corrected cells RBS cells were hypersensitive to the DNA-damaging agents mitomycin C, camptothecin and etoposide, while no particular sensitivity to UV, ionizing radiation, hydroxyurea or aphidicolin was found. The cohesion defect of RBS cells and their hypersensitivity to DNA-damaging agents were not corrected by a patient-derived ESCO2 acetyltransferase mutant (W539G), indicating that the acetyltransferase activity of ESCO2 is essential for its function. In contrast to a previous study on cells from patients with Cornelia de Lange syndrome, another cohesinopathy, RBS cells failed to exhibit excessive chromosome aberrations after irradiation in G2 phase of the cell cycle. Our results point at an S phase-specific role for ESCO2 in the maintenance of genome stability

Measuring and Analysis of Nonlinear Characterization of Lithium-Ion Batteries Using Multisin Excitation Signal

This paper introduces a novel methodology for analysis in the frequency domain. This methodology looks to the battery from a different point of view and covers aspects of the battery that is often neglected in other works and analysis battery precisely. Using periodic signals such as random phase multisine for system identification, allows separating noise and nonlinear distortions from the linear part of the system’s response. In addition to a shorter test time in comparison with conventional single sine EIS, by performing extra periods and different phase realizations, transients are eliminated and noise disturbance and also nonlinear distortion is detected

Lithium-Ion Capacitors: Characterization and Modeling at Both High and Low Temperatures

International audienc

Aging and degradation of lithium-ion batteries

International audiencePerformance, lifetime, and cost of hybrid electric vehicles and similar applications requiring peak power are directly affected by battery lifetime, performance, cost, and reliability. Different types of rechargeable energy storage systems exist in the market but none can fulfill all the demands but, rather, are designed for specific applications and uses. The performance of lithium-ion batteries is strongly affected by environmental conditions (e.g., operating temperature) and affecting cycling behavior and side reactions resulting in capacity losses. The aging degradation and reduction of the battery lifetime is subject to nonlinear phenomena influenced by temperature and another operational conditions. This chapter focuses on the degradation mechanisms inside lithium iron phosphate batteries (7 Ah cells) at different storage temperatures (60, 40, 25, 10, 0, and − 10 °C) and state of charge (SoC) levels (100%, 75%, 50%, and 25%). From the experimental results, one can observe that the capacity degradation is considerably higher at higher storage temperatures (e.g., 60 and 40 °C) compared to lower temperatures. The higher-capacity degradation is related to the parasitic reactions that occur at higher temperatures, whereby loss of active material and lithium-ion become determining factors. This observation has been confirmed by the increase of the internal resistance, whereby the main contributor is the growth of the solid electrolyte interface. Furthermore, the experimental results show that higher SoC levels have a negative impact on the battery capacity degradation compared to lower SoC levels (e.g., 25%). From the performed analysis, one can conclude that a lithium-ion battery should be kept in a temperature range lower than 40 °C and 75% SoC during its calendar life for guaranteeing long lifetime of the battery

Geometries of the antiproton-nucleus optical potentials at 180 MeV

The moments of the real and the absorptive parts of the antiproton optical potentials are evaluated for the first time to study the geometries of the potentials at 180 MeV. Interesting features are revealed which are found to be comparable to the proton case in general despite the presence of strong annihilation. A few interesting deviations, however, are also found compared to the proton case

Optimization of an advanced battery model parameter minimization tool and development of a novel electrical model for lithium-ion batteries

This paper represents the optimization of an advanced battery model parameter minimization tool for estimation of lithium-ion battery model parameters. This system is called extended Levenberg–Marquardt. The proposed system is able to predict the nonlinearity of lithium-ion batteries accurately. A fitting percentage of over 99% between the simulation and experimental results can be achieved. Then, this paper contains a new second-order electrical battery model for lithium-ion batteries, extracted on the basis of experimental study and able to predict the battery behavior precisely. Further, in this paper, an extended comparative study of the performances of the various existing electrical battery models in the literature (Rint, RC, Thévenin, and FreedomCar) for lithium-ion batteries against the new developed battery model is presented, on the basis of the optimized battery parameter minimization tool. These battery models have been validated at different working conditions. From the analysis, one can observe that the new proposed battery model is more accurate than the existing ones and that it can predict the battery behavior during transient and steady-state operations. Finally, the new battery model has been validated at different working temperatures. The analysis shows that the error percentage between 0% and 90% depth of discharge at 40 °C is less than 1.5% and at 0 °C less than 5%