218 research outputs found
Radon concentration in self-bottled mineral spring waters as a possible public health issue
Since 2013, the Council Directive 2013/51/Euratom has been regulating the content of radioactive substances in water intended for human consumption. However, mineral waters are exempted from this regulation, including self-bottled springs waters, where higher radon concentration are expected. Therefore, a systematic survey has been conducted on all the 33 mineral spring waters of Lazio (a region of Central Italy) in order to assess if such waters, when self-bottled, may be of concern for public health. Waters have been sampled in two different ways to evaluate the impact of bottling on radon concentration. Water sampling was possible for 20 different spring waters, with 6 samples for each one. The results show that 2 (10%) of measured mineral spring waters returned radon concentrations higher than 100âBqâLâ1, i.e., the parametric value established by the Council Directive. These results, if confirmed by other surveys involving a higher number of mineral spring waters, would suggest regulating also these waters, especially in countries like Italy for which: (i) mineral water consumption is significant; (ii) mineral concession owners generally allow the consumers to fill bottles and containers, intended for transport and subsequent consumption, directly from public fountains or from fountains within the plant; (iii) the consumersâ habit of drinking self-bottled mineral water is widespread
Models of radon exhalation from building structures: General and case-specific solutions.
Assessing the radon activity that exhales from building structures is crucial to identify the best strategies to prevent radon from entering a building or reducing its concentration in the inhabited spaces. The direct measurement is extremely difficult, so the common approach has consisted in developing models describing the radon migration and exhalation phenomena for building porous materials. However, due to the mathematical complexity of comprehensively modelling the radon transport phenomenon in buildings, simplified equations have been mostly adopted until now to assess the radon exhalation. A systematic analysis of the models applicable to radon transport has been carried out and it has resulted in four models differing in the migration mechanisms â only diffusive or diffusive and advective â and the presence of inner radon generation. The general solutions have been obtained for all the models. Moreover, three case-specific sets of boundary conditions have been formulated to account for all the actual scenarios occurring in buildings: both perimetral and partition walls and building structures in direct contact with soil or embankments. The corresponding case-specific solutions obtained serve as a key practical tool to improve the accuracy in assessing the contribution of building materials to indoor radon concentration according to the site-specific installation conditions in addition to the material inner properties
Bioprocessing of barley and lentil grains to obtain in situ synthesis of exopolysaccharides and composite wheat bread with improved texture and health properties
A comprehensive study into the potential of bioprocessing techniques (sprouting and sourdough fermentation) for improving the technological and nutritional properties of wheat breads produced using barley and lentil grains was undertaken. Dextran biosynthesis in situ during fermentation of native or sprouted barley flour (B or SB) alone or by mixing SB flour with native or sprouted lentil flour (SB-L or SB-SL) by Weissella paramesenteroides SLA5, Weissella confusa SLA4, Leuconostoc pseudomesenteroides DSM 20193 or Weissella confusa DSM 20194 was assessed. The acidi-fication and the viscosity increase during 24 h of fermentation with and without 16% sucrose (on flour weight), to promote the dextran synthesis, were followed. After the selection of the fermentation parameters, the bioprocessing was carried out by using Leuconostoc pseudomesenteroides DSM 20193 (the best LAB dextran producer, up to 2.7% of flour weight) and a mixture of SB-SL (30:70% w/w) grains, enabling also the decrease in the raffinose family oligosaccharides. Then, the SB-SL sourdoughs containing dextran or control were mixed with the wheat flour (30% of the final dough) and leavened with bakerâs yeast before baking. The use of dextran-containing sourdough allowed the production of bread with structural improvements, compared to the control sourdough bread. Compared to a bakerâs yeast bread, it also markedly reduced the predicted glycemic index, in-creased the soluble (1.26% of dry matter) and total fibers (3.76% of dry matter) content, giving pe-culiar and appreciable sensory attributes
A comparison between the effects of over-expression of miRNA-16 and miRNA-34a on cell cycle progression of mesothelioma cell lines and on their cisplatin sensitivity
The prognosis of patients affected by malignant pleural mesothelioma (MPM) is presently poor and no therapeutic strategies have improved their survival yet. Introduction of miRNA mimics to restore their reduced or absent functionality in cancer cells is considered an important opportunity and a combination of miR's might be even more effective. In the present study, miR-16 and miR-34a were transfected, singularly and in combination, in MPM cell lines H2052 and H28, and their effects on cell proliferation and sensitivity to cisplatin are reported. Interestingly, the overexpression of both miRs, alone or combined, slows down the cell cycle progression, modulates the p53 and HMGB1 expression and increases the sensitivity of cells to cisplatin, producing a marked impairment of cell proliferation and strengthening the apoptotic effect of the drug. However, the co-overexpression of the two miRs results more effective only in the regulation of the cell cycle, but does not enhance the sensitivity of MPM cells to cisplatin. Consequently, although the potential of miR-16 and miR-34a is confirmed, we must conclude that their combination does not improve the response of MPM to chemotherapy
Photoluminescence of radiation-induced color centers in lithium fluoride thin films for advanced diagnostics of proton beams
Systematic irradiation of thermally evaporated 0.8âÎŒm thick polycrystalline lithium fluoride films on glass was performed by proton beams of 3 and 7âMeV energies, produced by a linear accelerator, in a fluence range from 1011 to 1015 protons/cm2. The visible photoluminescence spectra of radiation-induced F2 and F3+ laser active color centers, which possess almost overlapping absorption bands at about 450ânm, were measured under laser pumping at 458ânm. On the basis of simulations of the linear energy transfer with proton penetration depth in LiF, it was possible to obtain the behavior of the measured integrated photoluminescence intensity of proton irradiated LiF films as a function of the deposited dose. The photoluminescence signal is linearly dependent on the deposited dose in the interval from 103 to about 106âGy, independently from the used proton energies. This behavior is very encouraging for the development of advanced solid state radiation detectors based on optically transparent LiF thin films for proton beam diagnostics and two-dimensional dose mapping
Beam commissioning of the 35Â MeV section in an intensity modulated proton linear accelerator for proton therapy
This paper presents the experimental results on the Terapia Oncologica con Protoni-Intensity Modulated Proton Linear Accelerator (TOP-IMPLART) beam that is currently accelerated up to 35 MeV, with a final target of 150 MeV. The TOP-IMPLART project, funded by the Innovation Department of Regione Lazio (Italy), is led by Italian National Agency for New Technologies, Energy and Sustainable Economic Development (ENEA) in collaboration with the Italian Institute of Health and the Oncological Hospital Regina Elena-IFO. The accelerator, under construction and test at ENEA-Frascati laboratories, employs a commercial 425 MHz, 7 MeV injector followed by a sequence of 3 GHz accelerating modules consisting of side coupled drift tube linac (SCDTL) structures up to 71 MeV and coupled cavity linac structures for higher energies. The section from 7 to 35 MeV, consisting on four SCDTL modules, is powered by a single 10 MW klystron and has been successfully commissioned. This result demonstrates the feasibility of a âfully linearâ proton therapy accelerator operating at a high frequency and paves the way to a new class of machines in the field of cancer treatment
Hydrogen sulfide inhibits tmprss2 in human airway epithelial cells: Implications for sarsâcovâ2 infection
The COVIDâ19 pandemic has now affected around 190 million people worldwide, accounting for more than 4 million confirmed deaths. Besides ongoing global vaccination, finding protective and therapeutic strategies is an urgent clinical need. SARSâCoVâ2 mostly infects the host organism via the respiratory system, requiring angiotensinâconverting enzyme 2 (ACE2) and transmembrane protease serine 2 (TMPRSS2) to enter target cells. Therefore, these surface proteins are considered potential druggable targets. Hydrogen sulfide (H2S) is a gasotransmitter produced by several cell types and is also part of natural compounds, such as sulfurous waters that are often inhaled as lowâintensity therapy and prevention in different respiratory conditions. H2S is a potent biological mediator, with antiâoxidant, antiâinflammatory, and, as more recently shown, also antiviral activities. Considering that respiratory epithelial cells can be directly exposed to H2S by inhalation, here we tested the in vitro effects of H2Sâdonors on TMPRSS2 and ACE2 expression in human upper and lower airway epithelial cells. We showed that H2S significantly reduces the expression of TMPRSS2 without modifying ACE2 expression both in respiratory cell lines and primary human upper and lower airway epithelial cells. Results suggest that inhalational exposure of respiratory epithelial cells to natural H2S sources may hinder SARSâCoVâ2 entry into airway epithelial cells and, consequently, potentially prevent the virus from spreading into the lower respiratory tract and the lung
Surface reservoirs dominate dynamic gas-surface partitioning of many indoor air constituents
Human health is affected by indoor air quality. One distinctive aspect of the indoor environment is its very large surface area that acts as a poorly characterized sink and source of gas-phase chemicals. In this work, air-surface interactions of 19 common indoor air contaminants with diverse properties and sources were monitored in a house using fast-response, on-line mass spectrometric and spectroscopic methods. Enhanced-ventilation experiments demonstrate that most of the contaminants reside in the surface reservoirs and not, as expected, in the gas phase. They participate in rapid air-surface partitioning that is much faster than air exchange. Phase distribution calculations are consistent with the observations when assuming simultaneous equilibria between air and large weakly polar and polar absorptive surface reservoirs, with acid-base dissociation in the polar reservoir. Chemical exposure assessments must account for the finding that contaminants that are fully volatile under outdoor air conditions instead behave as semivolatile compounds indoors
The Top-Implart Proton Linear Accelerator: Interim Characteristics of the 35 Mev Beam
In the framework of the Italian TOP-IMPLART project (Regione Lazio), ENEA-Frascati, ISS and IFO are developing and constructing the first proton linear accelerator based on an actively scanned beam for tumor radiotherapy with final energy of 150 MeV. An important feature of this accelerator is modularity: an exploitable beam can be delivered at any stage of its construction, which allows for immediate characterization and virtually continuous improvement of its performance. Currently, a sequence of 3 GHz accelerating modules combined with a commercial injector operating at 425 MHz delivers protons up to 35 MeV. Several dosimetry systems were used to obtain preliminary characteristics of the 35-MeV beam in terms of stability and homogeneity. Short-term stability and homogeneity better than 3% and 2.6%, respectively, were demonstrated; for stability an improvement with respect to the respective value obtained for the previous 27 MeV beam
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