Quantitative Correlations between Radiosensitivity Biomarkers Show That the ATM Protein Kinase Is Strongly Involved in the Radiotoxicities Observed after Radiotherapy

Tissue overreactions (OR), whether called adverse effects, radiotoxicity, or radiosensitivity reactions, may occur during or after anti-cancer radiotherapy (RT). They represent a medical, economic, and societal issue and raise the question of individual response to radiation. To predict and prevent them are among the major tasks of radiobiologists. To this aim, radiobiologists have developed a number of predictive assays involving different cellular models and endpoints. To date, while no consensus has been reached to consider one assay as the best predictor of the OR occurrence and severity, radiation oncologists have proposed consensual scales to quantify OR in six different grades of severity, whatever the organ/tissue concerned and their early/late features. This is notably the case with the Common Terminology Criteria for Adverse Events (CTCAE). Few radiobiological studies have used the CTCAE scale as a clinical endpoint to evaluate the statistical robustness of the molecular and cellular predictive assays in the largest range of human radiosensitivity. Here, by using 200 untransformed skin fibroblast cell lines derived from RT-treated cancer patients eliciting OR in the six CTCAE grades range, correlations between CTCAE grades and the major molecular and cellular endpoints proposed to predict OR (namely, cell survival at 2 Gy (SF2), yields of micronuclei, recognized and unrepaired DSBs assessed by immunofluorescence with γH2AX and pATM markers) were examined. To our knowledge, this was the first time that the major radiosensitivity endpoints were compared together with the same cohort and irradiation conditions. Both SF2 and the maximal number of pATM foci reached after 2 Gy appear to be the best predictors of the OR, whatever the CTCAE grades range. All these major radiosensitivity endpoints are mathematically linked in a single mechanistic model of individual response to radiation in which the ATM kinase plays a major role.     

Increased Weight Gain and Insulin Resistance in HF-Fed PLTP Deficient Mice Is Related to Altered Inflammatory Response and Plasma Transport of Gut-Derived LPS

Bacterial lipopolysaccharides (LPS, endotoxins) are found in high amounts in the gut lumen. LPS can cross the gut barrier and pass into the blood (endotoxemia), leading to low-grade inflammation, a common scheme in metabolic diseases. Phospholipid transfer protein (PLTP) can transfer circulating LPS to plasma lipoproteins, thereby promoting its detoxification. However, the impact of PLTP on the metabolic fate and biological effects of gut-derived LPS is unknown. This study aimed to investigate the influence of PLTP on low-grade inflammation, obesity and insulin resistance in relationship with LPS intestinal translocation and metabolic endotoxemia. Wild-type (WT) mice were compared with Pltp-deficient mice (Pltp-KO) after a 4-month high-fat (HF) diet or oral administration of labeled LPS. On a HF diet, Pltp-KO mice showed increased weight gain, adiposity, insulin resistance, lipid abnormalities and inflammation, together with a higher exposure to endotoxemia compared to WT mice. After oral administration of LPS, PLTP deficiency led to increased intestinal translocation and decreased association of LPS to lipoproteins, together with an altered catabolism of triglyceride-rich lipoproteins (TRL). Our results show that PLTP, by modulating the intestinal translocation of LPS and plasma processing of TRL-bound LPS, has a major impact on low-grade inflammation and the onset of diet-induced metabolic disorders.     

Preliminary experiments: High-energy alpha PIXE in archaeometry

This paper describes the work realized at the “Centre Européen d’Archéométrie” to highlight the utility of high-energy alpha PIXE in the particular field of archaeometry and to introduce the developments done and to be done to complete the knowledge of high-energy alpha PIXE.It starts with the comparison of the yield and the noise background between several alpha particle beams and the comparison between alpha particle and proton beams on different thick and thin references. After, this paper depicts the developments done at the “Institut de Physique Nucléaire, Atomique et Spectroscopie” to perform such high-energy experiments, first on standards and later on cultural heritage objects. Moreover, it introduces the problematics of such beams for the quantification in PIXE by the intermediary of the knowledge of the ionization and X-ray production cross-sections and also the developments done to answer to this serious lack in the databases.     

Influence of the Spark Plasma Sintering temperature on the structure and dielectric properties of BaTi(1-x)ZrxO3 ceramics

In this work, structural and dielectric properties of BaTi_(1-x)Zr_xO₃ (BTZ) ceramics prepared by Spark Plasma Sintering (SPS) from powders obtained via Self-propagating High-temperature Synthesis (SHS) are shown to be strongly affected by the sintering temperature. In addition, a post-annealing treatment in air of the as-prepared ceramics leads to a transition from the hexagonal to the tetragonal and cubic phases. The SPS ceramics corresponding to compositions 0.05 ≤ x ≤ 0.20 and obtained at a sintering temperature of 1200 °C exhibit a standard ferroelectric behavior. In contrast, a diffuse phase transition is observed for the case of ceramics sintered at higher temperatures. Finally, the BTZ ceramic containing 5 at.% of Zr displays the best dielectric permittivity and piezoelectric properties as compared to the other compositions taken into account.     

Liquid-phase exfoliation method to access cobalt oxide nanosheets in pH-neutral solutions

Two-dimensional materials have gained significant attention across the materials community due to their remarkable physical, chemical, electronic, and optical properties. With many two-dimensional materials discovered each year, investigations into their processing, scalability, and resulting properties are important to fully realize their potential in next-generation technologies. While numerous exfoliation techniques are available for a variety of two-dimensional materials, liquid-phase exfoliation techniques offer many advantages, particularly high throughput and scalability. Herein, we report a liquid-phase exfoliation method to access multilayer cobalt oxide nanosheets in pH-neutral aqueous solutions varying in size, concentration, and application. The size, thickness, and morphology of the multilayer nanosheets were confirmed using atomic force microscopy and transmission electron microscopy. Finally, selected cobalt oxide nanosheets underwent additional analysis of the crystallinity, structure, and cobalt valance.     

Structure,Mössbauer and AC susceptibility of strontium nanohexaferrites: Effect of vanadium ions doping

This study contains information about the effect of V³⁺ vanadium doping on structural, morphological and magnetic properties of SrFe_12-xV_xO₁₉ (x?=?0.00, 0.02, 0.04, 0.06, 0.08, 0.10) nanohexaferrites. Samples have been prepared via citrate sol-gel method and characterized. XRD and SEM analyses revealed the formation of M-type nanohexaferrites, wherein the particle size remained unaltered with the increase in vanadium contents. Mossbauer spectra disclosed the preferred occupation of V³⁺ ions at 4f₁ tetrahedral site. Zero field (ZFC) and field cooled (FC) magnetization data in the temperature range of 2–400?K did not exhibit any blocking temperature, indicating mostly the ferromagnetic long-range ordering for the studied nanohexaferrites. Moreover, at low temperatures a spin glass behavior was observed. The ac-susceptibility showed a weakening in the Fe³⁺ - O^2? - Fe³⁺ indirect exchange interactions with the increase in V³⁺ contents. Magnetic properties are argued in terms of the empirical rules of indirect exchange interactions taking into account the substitution of Fe³⁺ cations by V³⁺ ones in the preferred sites.     

Screening of Some Essential Oil Constituents as Potential Inhibitors of the ATP Synthase of Escherichia coli

Many novel bacterial targets and natural inhibitors of enzymes are currently being considered to overcome antibiotic resistance of Escherichia coli. Hence, in this study, 20 essential oil constituents were screened for their potential inhibitory effect on E. coli ATP synthase. This enzyme is involved in the hydrolysis of ATP into ADP and inorganic phosphate (Pi). First, E. coli membrane ATP synthase was isolated via cell lysis. A spectrophotometric method was optimized to quantify the released phosphate from ATP hydrolysis in order to follow the enzymatic activity. The method was validated by determining the kinetic parameters of this reaction (K_m = 144.66 μM and V_max = 270.27 μM/min), and through the inhibition assays of ATP synthase using three reference inhibitors, thymoquinone (half maximal inhibitory concentration [IC₅₀] = 50.93 μM), resveratrol (maximum inhibition of 40%), and quercetin (IC₅₀ = 29.01 μM). Among the studied essential oil components, α‐terpinene was the most potent inhibitor (IC₅₀ = 19.74 μM) followed by β‐pinene, isoeugenol, eugenol, and estragole.     

Towards price-based predictive control of a small-scale electricity network

ABSTRACT

With the increasing deployment of battery storage devices in residential electricity networks, it is essential that the charging and discharging of these devices be scheduled so as to avoid adverse impacts on the electricity distribution network. In this paper, we propose a non-cooperative, price-based hierarchical distributed optimisation approach that provably recovers the centralised, or cooperative, optimal performance from the point of view of the network operator. The distributed optimisation algorithm provides important insights into the appropriate design of contracts between an energy provider and their associated residential customers, who can themselves act as energy providers as well as consumers (e.g. due to rooftop solar photovoltaics and batteries) depending on the time of the day and on real-time prices. To make the presentation self-contained, and to highlight key properties of the price-based optimisation algorithm, the dual ascent method and its convergence properties are reviewed. The performance of the proposed price-based optimisation algorithm is validated on recent measurement taken from an Australian electricity distribution company, Ausgrid. In addition to analysing the results of the open loop solution, we investigate the effect of real-time prices in the closed loop using a model predictive control framework.