14 research outputs found

    Factors controlling 226Ra, 228Ra and their activity ratio in groundwater – an application in Polish Carpathian mineral waters

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    The influences of aquifer formations and water chemical composition on the occurrence and activity ratio of radium isotopes in groundwater are discussed. Based on the model of desorption/adsorption processes of natural radionuclides in the rock-water system, the concentrations of radium isotopes and their activity ratio in groundwater are evaluated by the numerical Monte Carlo method (MC). In cases where the groundwater is of a similar age, limited flow (up to several meters/year), the physical conditions and the uranium and thorium activity ratios in host water formations are similar, the activity concentrations of radium isotopes (226Ra, 228Ra) and their activity ratio (226Ra/228Ra) are the highest in the water of high desorption coefficient for chloride sodium water (domination of Cl− , Na+ ions), medium in water of moderate desorption (bicarbonate water – HCO3 − , Ca2+) and the lowest in waters with a low desorption coefficient (sulfate ions prevailing – SO4 2−, Ca2−). The statements are well confirmed in the case of the natural mineral waters from the Polish Outer Carpathians. The total dissolved solids (TDS) of the Polish Carpathians waters varies from several hundred milligrams per liter to several tens of thousands milligrams per liter. The minimum, maximum and average concentrations of 226Ra, 228Ra and their activity ratio (226Ra/228Ra) are 82, 1340, 456 mBq/L, 19, 1240, 354 mBq/L and 0.89, 7.6 and 2.0 for chloride waters; 4, 140, 45.8 mBq/L, 12, 171, 62.7 mBq/L and 0.3, 1.7 and 0.70 for bicarbonate waters and 0.8, 9.3, 3.6 mBq/L, 5.3, 54, 20.1 mBq/L and 0.1, 1.0, 0.3 for sulfate ones, respectively. The desorption coefficients are the highest for the Cl-Na, moderate for the HCO3-Ca and the lowest for the SO4-Ca waters (in contrast to the adsorption properties of these waters)

    Asymmetric dimethylarginine as a useful risk marker of radial artery calcification in patients with advanced kidney disease

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    Medial arterial calcification is common in patients with chronic kidney disease (CKD) and is considered a risk factor for morbidity and mortality. We aimed to evaluate the correlation between asymmetric dimethylarginine (ADMA) levels, radial artery calcification, and common carotid artery intima-media thickness (CCA‑IMT). The study included 51 patients with CKD, in whom an arteriovenous fistula for hemodialysis access was created to collect radial artery samples for a histological examination, and 33 healthy volunteers, in whom the reference concentrations of ADMA were assessed. The concentrations of creatinine, albumin, calcium, phosphate, fibroblast growth factor 23, osteoprotegerin (OPG), osteopontin (OPN), osteocalcin, secreted protein acidic and rich in cysteine, interleukin 6, interleukin 18, pentraxin 3, stromal cell‑derived factor 1α1\alpha (SDF1αSDF1\alpha), thrombomodulin, soluble tumor necrosis factor receptor II (sTNFRII), and matrix metalloproteinase 2 (MMP‑2) were determined. Radial artery fragments were stained for calcifications using alizarin red. The CCA‑IMT was assessed by ultrasonography. Patients with CKD had higher ADMA levels than controls. Patients with ADMA levels above the median were older, had higher levels of phosphate, fibroblast growth factor 23, OPG, OPN, PTX3, sTNFRII, MMP‑2, thrombomodulin, and they had more atherosclerotic plaques in the carotid artery. In multiple regression, log‑transformed (log)sTNFRII, MMP‑2, and SDF1αSDF1\alpha levels were independent predictors of log(ADMA). Patients with calcifications had higher ADMA levels. A similar correlation was observed between SDF1αSDF1\alpha and alizarin red staining grades 1 to 3. In logistic regression, ADMA levels positively predicted the presence of calcifications independently of age, hemodialysis status, Framingham risk score, and PTX3. Circulating ADMA levels indicate medial arterial calcification in patients with CKD

    Satisfaction and discontent of Polish patients with biological therapy of rheumatic diseases : results of a multi-center questionnaire study

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    Objectives: Biologics are medications widely applied in the management of inflammatory rheumatic diseases. The drugs were found to be effective but their application is associated with some disadvantages. Medication with biologics is relatively expensive, and in Poland, it is carried out in specialized centers. The study was designed to evaluate various aspects of satisfaction and dissatisfaction of Polish patients treated with biologics. Material and methods: An anonymous questionnaire was distributed in 23 Polish rheumatological centers involved in the treatment; 1212 returned questionnaires were used for analysis. Responses were received from 606 patients with rheumatoid arthritis, 427 with ankylosing spondylitis, 117 psoriatic arthritis, and 62 adult patients with juvenile idiopathic arthritis (in whom administration of the drugs had been introduced before they were 18 years old). The investigated group constituted about one-fifth of all rheumatic patients on biologics in Poland. Results: A beneficial or very beneficial influence of the medication on the state of physical health was found mostly in patients with rheumatoid arthritis (51.3 and 30.5%) and ankylosing spondylitis (51.0 and 36.8%). Family life was improved by the treatment especially in patients with ankylosing spondylitis (40.7 and 35.6% beneficial and very beneficial, respectively), sleep quality and sexual life mostly in those with ankylosing spondylitis (beneficial/very beneficial influence 41.5/38.4, and 38.7/23.9, respectively). There was a rather small influence of biological treatment on the financial situation of the patients. In general, satisfaction with the treatment was evaluated as positive or very positive in 88% of all investigated patients. In a significant part of the patients, transportation to the medical center was considered as a disadvantage of the treatment. About one-third of the patients considered laboratory and imaging tests to be done before initiation of the medication as a difficulty, and for about 40% waiting time for qualification for the medication was a significant disadvantage. The route of drug administration was without importance for 4/5 of the patients. Conclusions: Summing up, the results were similar in the patients suffering from various diseases although those with psoriatic arthritis felt the highest satisfaction (possibly due to the positive aesthetic effect), and those with ankylosing spondylitis had significant improvement in sexual life (probably due to younger age). Relatively low satisfaction was found in patients with juvenile idiopathic arthritis. There was a small influence of medication on financial status of the patients. Application of biologics has few disadvantages and most of them are associated with the organization of health services (waiting time for the tests, transportation to the medical centers)

    Coupling of high temperature nuclear reactor with chemical plant by means of steam loop with heat pump

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    High temperature nuclear reactors (HTR) can be used as an excellent, emission-free source of technological heat for various industrial applications. Their outlet helium temperature (700°-900°C) allows not only for heat supply to all processes below 600°C (referred to as “steam class”), but also enables development of clean nuclear-assisted hydrogen production or coal liquefaction technologies with required temperatures up to 900°C (referred to as “chemical class”). This paper presents the results of analyses done for various configurations of the steam transport loop coupled with the high-temperature heat pump designed for “chemical class” applications. The advantages and disadvantages as well as the key issues are discussed in comparison with alternative solutions, trying to answer the question whether the system with the steam loop and the hightemperature heat pump is viable and economically justified

    Analysis of websites content about anti-vaccination topic

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    Validation of VHTRC calculation benchmark of critical experiment using the MCB code

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    The calculation benchmark problem Very High Temperature Reactor Critical (VHTR) a pin-in-block type core critical assembly has been investigated with the Monte Carlo Burnup (MCB) code in order to validate the latest version of Nuclear Data Library based on ENDF format. Executed benchmark has been made on the basis of VHTR benchmark available from the International Handbook of Evaluated Reactor Physics Benchmark Experiments. This benchmark is useful for verifying the discrepancies in keff values between various libraries and experimental values. This allows to improve accuracy of the neutron transport calculations that may help in designing the high performance commercial VHTRs. Almost all safety parameters depend on the accuracy of neutron transport calculation results that, in turn depend on the accuracy of nuclear data libraries. Thus, evaluation of the libraries applicability to VHTR modelling is one of the important subjects. We compared the numerical experiment results with experimental measurements using two versions of available nuclear data (ENDF-B-VII.1 and JEFF-3.2) prepared for required temperatures. Calculations have been performed with the MCB code which allows to obtain very precise representation of complex VHTR geometry, including the double heterogeneity of a fuel element. In this paper, together with impact of nuclear data, we discuss also the impact of different lattice modelling inside the fuel pins. The discrepancies of keff have been successfully observed and show good agreement with each other and with the experimental data within the 1 σ range of the experimental uncertainty. Because some propagated discrepancies observed, we proposed appropriate corrections in experimental constants which can improve the reactivity coefficient dependency. Obtained results confirm the accuracy of the new Nuclear Data Libraries

    Modelling of a proton spot scanning system using MCNP6

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    The aim of this work was to model the characteristics of a clinical proton spot scanning beam using Monte Carlo simulations with the code MCNP6. The proton beam was defined using parameters obtained from beam commissioning at the Skandion Clinic, Uppsala, Sweden. Simulations were evaluated against measurements for proton energies between 60 and 226 MeV with regard to range in water, lateral spot sizes in air and absorbed dose depth profiles in water. The model was also used to evaluate the experimental impact of lateral signal losses in an ionization chamber through simulations using different detector radii. Simulated and measured distal ranges agreed within 0.1 mm for R90 and R80, and within 0.2 mm for R50. The average absolute difference of all spot sizes was 0.1 mm. The average agreement of absorbed dose integrals and Bragg-peak heights was 0.9%. Lateral signal losses increased with incident proton energy with a maximum signal loss of 7% for 226 MeV protons. The good agreement between simulations and measurements supports the assumptions and parameters employed in the presented Monte Carlo model. The characteristics of the proton spot scanning beam were accurately reproduced and the model will prove useful in future studies on secondary neutrons.Funding agencies:This work was partially supported by the Swedish Radiation Safety Authority under the contract SSM2016-2425. The authors declare no conflict of interest.</p

    Role of Diagnostic Imaging in Chronic Recurrent Multifocal Osteomyelitis (CRMO) in Children: An Observational Study

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    The aim of this single-center observational study was to analyze the applicability of various imaging studies to the diagnosis and further evaluation of patients with chronic recurrent multifocal osteomyelitis (CRMO). The analysis included the data of 10 patients with CRMO treated between 2016 and 2021. The mean ages of the patients at the first manifestation of CRMO and ultimate diagnosis were 10 years and 7 months and 11 years and 10 months, respectively. Conventional radiography demonstrated focal loss of bone density in only 30% of the patients. Computed tomography showed disseminated foci with non-homogeneous osteolytic/osteosclerotic structure, with a massive loss of cortical layer and strong periosteal reaction. On magnetic resonance imaging (MRI), most patients presented with multifocal hypodense areas on T1-weighted images, with the enhancement of signal on T-weighted and STIR sequences. The duration of follow-up varied between 3 months and 3 years. In 40% of the patients, both clinical symptoms and the abnormalities seen on MRI resolved completely, whereas another 50% showed partial regression of clinical and radiological manifestations. MRI findings, co-existing with characteristic clinical manifestations, play a pivotal role in establishing the ultimate diagnosis of CRMO. MRI can also be used to monitor the outcomes of treatment in CRMO patients

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