CONSIDERATIONS REGARDING THE DEVELOPMENT OF A PHOTOVOLTAIC PARK LOCATED IN DEFILEUL JIULUI AREA

The paper presents the simulation results for a photovoltaic park in terms of its energy production capability and environmental impact. The energy generated by the photovoltaic system would be used for household purposes, for the nearby villages. In order to accurately simulate the energy production of this renewable energy source there were performed two types of calculation sets and a comparative evaluation between the

Correlation between the radiation responses of fibroblasts cultured from individual patients and the risk of late reaction after breast radiotherapy.

Late normal tissue toxicity varies widely between patients and limits breast radiotherapy dose. Here we aimed to determine its relationship to DNA damage responses of fibroblast cultures from individual patients. Thirty-five breast cancer patients, with minimal or marked breast changes after breast-conserving therapy consented to receive a 4 Gy test irradiation to a small skin field of the left buttock and have punch biopsies taken from irradiated and unirradiated skin. Early-passage fibroblast cultures were established by outgrowth and irradiated in vitro with 0 or 4 Gy. 53BP1 foci, p53 and p21/CDKN1A were detected by immunofluorescence microscopy. Residual 53BP1 foci counts 24 h after in vitro irradiation were significantly higher in fibroblasts from RT-sensitive versus RT-resistant patients. Furthermore, significantly larger fractions of p53- but not p21/CDKN1A-positive fibroblasts were found in cultures from RT-sensitive patients without in vitro irradiation, and 2 h and 6 d post-irradiation. Exploratory analysis showed a stronger p53 response 2 h after irradiation of fibroblasts established from patients with severe reaction. These results associate the radiation response of fibroblasts with late reaction of the breast after RT and suggest a correlation with severity

The effect of radio-adaptive doses on HT29 and GM637 cells

<p>Abstract</p> <p>Background</p> <p>The shape of the dose-response curve at low doses differs from the linear quadratic model. The effect of a radio-adaptive response is the centre of many studies and well known inspite that the clinical applications are still rarely considered.</p> <p>Methods</p> <p>We studied the effect of a low-dose pre-irradiation (0.03 Gy – 0.1 Gy) alone or followed by a 2.0 Gy challenging dose 4 h later on the survival of the HT29 cell line (human colorectal cancer cells) and on the GM637 cell line (human fibroblasts).</p> <p>Results</p> <p>0.03 Gy given alone did not have a significant effect on both cell lines, the other low doses alone significantly reduced the cell survival. Applied 4 h before the 2.0 Gy fraction, 0.03 Gy led to a significant induced radioresistance in GM637 cells, but not in HT29 cells, and 0.05 Gy led to a significant hyperradiosensitivity in HT29 cells, but not in GM637 cells.</p> <p>Conclusion</p> <p>A pre-irradiation with 0.03 Gy can protect normal fibroblasts, but not colorectal cancer cells, from damage induced by an irradiation of 2.0 Gy and the application of 0.05 Gy prior to the 2.0 Gy fraction can enhance the cell killing of colorectal cancer cells while not additionally damaging normal fibroblasts. If these findings prove to be true in vivo as well this may optimize the balance between local tumour control and injury to normal tissue in modern radiotherapy.</p

H2AX phosphorylation at the sites of DNA double-strand breaks in cultivated mammalian cells and tissues

A sequence variant of histone H2A called H2AX is one of the key components of chromatin involved in DNA damage response induced by different genotoxic stresses. Phosphorylated H2AX (γH2AX) is rapidly concentrated in chromatin domains around DNA double-strand breaks (DSBs) after the action of ionizing radiation or chemical agents and at stalled replication forks during replication stress. γH2AX foci could be easily detected in cell nuclei using immunofluorescence microscopy that allows to use γH2AX as a quantitative marker of DSBs in various applications. H2AX is phosphorylated in situ by ATM, ATR, and DNA-PK kinases that have distinct roles in different pathways of DSB repair. The γH2AX serves as a docking site for the accumulation of DNA repair proteins, and after rejoining of DSBs, it is released from chromatin. The molecular mechanism of γH2AX dephosphorylation is not clear. It is complicated and requires the activity of different proteins including phosphatases and chromatin-remodeling complexes. In this review, we summarize recently published data concerning the mechanisms and kinetics of γH2AX loss in normal cells and tissues as well as in those deficient in ATM, DNA-PK, and DSB repair proteins activity. The results of the latest scientific research of the low-dose irradiation phenomenon are presented including the bystander effect and the adaptive response estimated by γH2AX detection in cells and tissues

Critical assessment of thermodynamic properties of CsI solid, liquid and gas phases

International audienceThermodynamic data for the CsI compound, including solid, liquid and are important for the calculation of iodine release in the case of severe nuclear accident: - (i) for accurate evaluation of the nature of iodine containing volatile compounds, and - (ii) for scaling kinetic data that are important in the calculations of intermediate states at short release time. The present study is a critical analysis of thermochemical data for the CsI compound based on available literature data. Revised values of the heat capacity for the liquid phase are proposed within the range of available experimental thermodynamic determinations. Vapor pressure data are assessed and accurate values of the standard enthalpies of formation of the gaseous monomer CsI(g) and dimer Cs2I2(g) are proposed: Delta H-f degrees (CsI, g,298.15 K) = -153.3 +/- 1.8 kJ . mol(-1), Delta H-f degrees (Cs2I2, g,298.15 K) = -469.2 +/- 5 kJ . mol(-1). The trimer Cs3I3(g) also exists as well as tetramer species in smaller amounts, less than 0.1% up to 1500 K

Knudsen cell mass spectrometric study of the Cs2IOH(g) molecule thermodynamics

International audienceThe gas phase of the CsI + CsOH system is analyzed by high temperature Knudsen cell mass spectrometry in order to confirm the existence of the Cs2IOH(g) complex molecule. The mass spectrometric analysis is quite complex since such molecules undergo dissociative ionization into fragment ions that mix with the same ions from dimers of the pure compounds in the same vapor phase. Varying the chemical conditions for vaporization by using different CsI + CsOH mixture contents showed that the ionization of the Cs2IOH(g) molecule led to five different fragment ions, Cs2OH+, Cs2I+, Cs+, CsOH+ and CsI+. This complex ionization pattern was studied in relation with previous assessed values for the vaporization of CsOH and CsI pure compounds in which monomer and dimer molecules are predominant. The equilibrium constant for the reaction CsI(g) + CsOH(g) = Cs2IOH(g) was determined and, after modeling the structure of the Cs2IOH molecule, the enthalpy of formation was determined using the third law of thermodynamics, as follows: Delta H-f degrees(Cs2IOH, g, 298.15 K) = -578 +/- 14.7 kJ.mole(-1). (c) 2013 Published by Elsevier Ltd

Analyzing the market performance of Romanian firms: do the COVID-19 crisis and classification type matter?

Purpose: Stock market performance is paramount to every country, as it signifies economic growth, business performance, wealth maximization, savings deployment, and consumer confidence. This study investigates differences in the market performance of listed firms in Romania. This study also examines whether the COVID-19 crisis affected market performance. Methodology: Data were collected from 69 firms listed on the Bucharest Stock Exchange (BSE) from 2018 to 2022, belonging to 11 sectors. This study used several methods to achieve its objectives. Difference tests were considered to analyze the performance of Romanian companies before and during the COVID-19 crisis, as well as across sectors. Regression analysis was also conducted to estimate the effect of the COVID-19 crisis and classification type on Romanian companies' performance. Additional analyses were performed to verify the findings of the present study. Findings: The study’s findings indicate a discernible difference in market performance between the pre-crisis and crisis periods. COVID-19 negatively impacts market performance. In addition, there is a discernible difference in market performance between sectors. The communication services sector has specifically demonstrated accelerated growth. Originality: This research analyzes the differences in the market performance of companies during pre-Covid-19 and the COVID-19 periods and across different sectors. It also provides evidence of the potential impact of COVID-19 on firms’ market performance. This research contributes to a better understanding of how sectors perform during a crisis

Développements de dépôts ALD : expériences et évaluations thermodynamiques

International audienc

Développements de dépôts ALD : expériences et évaluations thermodynamiques

International audienc

Developments of ALD Processes: Experiments and Thermodynamic Evaluations

International audienc