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41.
Dosimetry and spectrometry measurements have been carried out in the thermal column of the research fast reactor RSV-TAPIRO (ENEA-Casaccia, Rome) in order to investigate its suitability for irradiation of cells or mice, with a view to research in the interests of boron neutron capture therapy (BNCT). The thermal column consists of a graphite moderator (40 cm thick) containing a lead shield (13 cm thick) in order to shield reactor background. The irradiation volume, inside this structure, has cubic shape (18 x 18 x 18 cm3). Besides measurements of fluence and dose rates in air or in phantom performed with thermoluminescence dosemeters (TLDs) and using the activation technique, dose and fluence profiles have been generated using a method based on gel dosemeters analysed with optical imaging. To check the consistency of the results, spectrometry measurements in the same irradiation volume have been performed by means of bubble detectors.  相似文献   
42.
The paper describes an integrated procedure for evaluation of the service-life curve of existing bridges, calibrated with data derived from visual inspections and aimed at assessing the degree of deterioration of their structural/non-structural elements. Visual inspections allowed a total sufficiency rating for the bridges to be calculated, together with data collection, to be used in Bayesian updating of element deterioration curves. The results were combined with information from simulations of potential bridge deterioration scenarios to quantify mean trends and related uncertainties of the remaining service-life curves of existing bridges. The proposed procedure was applied to two bridge stocks and results are critically discussed. The method used may allow public authorities/private managing companies to optimise economic resources allocated to long/medium-term maintenance plans for the most critical structures.  相似文献   
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44.
HiDOSE (Heavy ion DOSimetry Experiment) and nDOSE (neutron DOSimetry Experiment) experiments conducted as a part of BIOKIS (Biokon in Space) payload were designed to measure the dose equivalent due to charged particles and to neutron field, on the entire energy range, during STS-134 mission. Given the complexity of the radiation field in space environment, dose measurements should be considered an asset of any space mission, and for this reason HiDOSE and nDOSE experiments represent an important contribution to the radiation environment assessment during this mission, a short duration flight. The results of these experiments, obtained using Thermo Luminescence Dosimeters (TLDs) to evaluate the charged particles dosimetry and neutron bubbles dosimeters and stack bismuth track dosimeters for neutron dosimetry, indicate that the dose equivalent rate due to space radiation exposure during the STS-134 mission is in accordance with the results obtained from long duration flights.  相似文献   
45.
A synchrotron radiation microscope based on X-ray fluorescence and computed microtomography for advanced applications in biomedicine, environmental sciences, geology and materials science is described. This microscope will utilize the radiation produced by a bending magnet of ELETTRA, the third-generation, high-brilliance synchrotron radiation facility being built in Trieste. Various wide-band-pass mirror systems operating in an energy range between 7 and 17 keV have been designed. For example, multilayer-coated mirrors in the Kirkpatrick-Baez configuration can produce a spatial resolution of 1 μm2 for a flux in excess of 108 photons per second on the sample (E = 12 keV, EE = 10). This X-ray microprobe will allow micrometric mapping of trace and minor elements and computed tomographic imaging with high resolution, opening a new realm of experiments in different fields of science, such as in vivo elemental scanning and microtomography of cultured cells, analysis of single atmospheric particulates, analysis of cosmic debris collected from the stratosphere and antarctic ice, etc. The preliminary design of the beam line and the performance of the microprobe are discussed.  相似文献   
46.
Bremsstrahlung photon beams produced by LINAC accelerators are currently the most used radiotherapy method for tumour treatments. When the photon energy exceeds the (gamma,n) reaction threshold energy, the patient receives an undesired dose due to photoneutron production both in the accelerator head and in the human body. In this paper, a method is presented for the assessment of the photoneutron spectra produced by Giant Dipole Resonance (GDR) during cancer radiotherapy with energetic photon beams. Experimental and numerical results have been obtained for the facility at Onkologik Klinik, Lund (Sweden), which is based on an ELEKTA 18 MV LINAC. Neutron spectra are evaluated both at the patient plane and inside an anthropomorphic phantom.  相似文献   
47.
Cancer is the second leading cause of death in developed countries and poor diet and physical inactivity are major risk factors in cancer-related deaths. Therefore, interventions to reduce levels of smoking, improve diet, and increase physical activity must become much higher priorities in the general population's health and health care systems. The consumption of fruit and vegetables exerts a preventive effect towards cancer and in recent years natural dietary agents have attracted great attention in the scientific community and among the general public. Foods, such as tomatoes, olive oil, broccoli, garlic, onions, berries, soy bean, honey, tea, aloe vera, grapes, rosemary, basil, chili peppers, carrots, pomegranate, and curcuma contain active components that can influence the initiation and the progression of carcinogenesis, acting on pathways implied in cell proliferation, apoptosis and metastasis. The present review illustrates the main foods and their active components, including their antioxidant, cytotoxic, and pro-apoptotic properties, with a particular focus on the evidence related to cancers of the digestive system.  相似文献   
48.
In this article, a new approach is applied to reuse Artemisia residue (AR) as filler in polyurethane (PU) foam for vegetable oil sorption for discarded cooking oil applications. The pristine PU and PU/X%AR foams (X stands for AR content of 5–20%wt/wt) were characterized by SEM, density, contact angle (CA), thermogravimetric analysis, and Fourier transform infrared spectroscopy. The influence of two experimental factors, such as contact time (30–180 s) and initial vegetable oil concentration (20–200 g/L), was investigated in vegetable oil and vegetable oil/mineral water systems. The AR loading of the foams increased the foams' density and influenced the morphological, physical, thermal, and sorption properties. The PU/20%AR sample presented the highest CA (122.5°) and the best sorption capacity and efficiency in both systems due to the small pores size and higher frequency of pores. Langmuir and Freundlich isotherm models well defined the sorption mechanisms. The Langmuir model represented the best fit of experimental data for PU/20%AR with a maximum adsorption capacity of 16.86 g/g. The PU/20%AR presented reusability of 7 cycles, conserving their hydrophobicity after the process. Therefore, AR is an innovative route as fillers in PU foams for discarded vegetable oil sorption, and the circular economy can benefit from the reuse of discarded vegetable cooking oil.  相似文献   
49.
BACKGROUND: As part of the regional programme for accident prevention, as much detailed information as possible was collected on the epidemiology of accidents involving children in our local Public Health area. A prospective survey was started of accidents reported to the Emergency Wards of the two hospitals in our Local Public Health area and the outpatient clinics of the pediatricians collaborating with the study. The survey was performed from 1 March to 31 August 1996. METHODS: A total of 737 reports of accidents involving children aged between 0 and 15 years old (483 males and 254 females) were collected and compared to other series available in the literature. Data were collected using standard forms containing personal details, date, time, place. The form also recorded how the accident occurred, the injuries it caused, the results and the place where First Aid treatment was provided. The causes of accidents were classified using the ICD 9 classification. RESULTS: Males were the most frequently affected (male-female ratio: 1.9:1) and the ages most frequently involved were 1-5 and over 10 years old; moreover, it was observed that accidents occurred during two peak times: 10-12 a.m. and 4-8 p.m. The most frequent accidents were falls, followed by road accidents and wounds. Among both males and females, the most frequent injuries were those to limbs, followed by cranio-facial injuries; wounds were predominantly surface rather than deep. 13.3% of the cases reported were admitted to hospital. CONCLUSIONS: These findings underline the importance of the problem even in a non-metropolitan area and the need to make every effort to ensure a safe and serene future for our children.  相似文献   
50.
The monomanual pupil stretcher is a new instrument that allows the authors to easily, quickly, and safely stretch the pupil. The specific features of the hooks allow pupil stretching to be performed in a single maneuver and in a more effective manner.  相似文献   
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