Alpha self-absorption evaluation in radiometric filter material for the natural range of alpha energy (5-9 MeV)

In this paper, SRIM (The Stopping and Range of Ions in Matter) software package is used to simulate the interaction of alpha particles into the material of radiometric analytical filters. The effect of alpha particle self-absorption in alpha radiometric filters measurements is estimated, especially in the range of natural alpha energy (5-9 MeV, Radon and Thoron alpha energy). Software package SRIM allows to calculate the parameters of the ions interaction with target material using a Monte Carlo simulation method based on a quantum mechanical treatment of ion-atom collisions. The effect of the radiometric analytical filter material on the transmitted efficiency of alpha energy is discussed. As the energy increases the self-absorption in analytical filter material is decreased but still has a clear effect. In this case, the filter material and the space distance between the filter and the detector window decrease the number of alpha particles which reach to the detector window. © 2019 RAD Association. All rights reserved

Inhomogeneous charged pion condensation phenomenon in the NJL2_2 model with quark number and isospin chemical potentials

The properties of two-flavored massive Nambu--Jona-Lasinio model in (1+1)-dimensional spacetime are investigated in the presence of isospin and quark number chemical potentials. The consideration is performed in the large-$N_c$ limit, where $N_c$ is the number of colored quarks. It is shown in the framework of this model that charged pion condensation phenomenon of dense quark/hadron isotopically asymmetric matter is rather a spatially inhomogeneous than a homogeneous one.Comment: 11 pages, 8 figures; version accepted for publication in PRD. arXiv admin note: text overlap with arXiv:1106.2928, arXiv:1102.407

Effect of electronic cigarette (EC) aerosols on particle size distribution in indoor air and in a radon chamber

Particle size distribution is an important factor governing whether aerosols can be deposited in various respiratory tract regions in humans. Recently, electronic cigarette (EC), as the alternative of tobacco cigarette, has become increasingly popular all over the world. However, emissions from ECs may contribute to both indoor and outdoor air pollution; moreover, comments about their safety remain controversial, and the number of users is increasing rapidly. In this investigation, aerosols were generated from ECs and studied in the indoor air and in a chamber under controlled conditions of radon concentration. The generated aerosols were characterized in terms of particle number concentrations, size, and activity distributions by using aerosol diffusion spectrometer (ADS), diffusion battery, and cascade impactor. The range of ADS assessment was from 10 -3 μm to 10 μm. The number concentration of the injected aerosol particles was between 40 000 and 100 000 particles/cm 3 . The distribution of these particles was the most within the ultrafi ne particle size range (0-0.2 μm), and the other particle were in the size range from 0.3 μm to 1 μm. The surface area distribution and the mass size distribution are presented and compared with bimodal distribution. In the radon chamber, all distributions were clearly bimodal, as the free radon decay product was approximately 1 nm in diameter, with a fraction of ~0.7 for a clean chamber (without any additional source of aerosols). The attached fraction with the aerosol particles from the ECs had a size not exceeding 1.0 μm. © 2019 H. N. Khalaf, M. Y. A. Mostafa & M. Zhukovsky

Radiopharmaceutical dose distribution in different organs and tissues for Lu-177 with different carrier

177Lu refers to rare earth elements from a group of lanthanides. Relative to its short time span, 177Lu has virtually pervaded all areas of in vivo radionuclide therapy and becomes one of important keys for therapeutic radionuclides of choice for targeted radionuclide therapy. The rising interest in the use of 177Lu in targeted molecular therapies has primarily developed from recent unmatched advances in molecular and cell biology, which include the use of peptides targeted to cell surface receptors, which are overexpressed on the surface of tumour cells. Therefore, the use of 177Lu-labelled radiopharmaceuticals have been the major factors evoking excitement among researchers and capturing the imagination of the clinical community thanks to advances in molecular and cellular biology. In this work, radiopharmaceutical comparison for 177Lu absorbed dose in health human organs and tissues is presented. The comparison between unlabelled 177Lu (ionic form) and labelled with 177Lu-MDP (methylenediphosphonate) and 177Lu-MAb (monoclonal antibodies). The biokinetic model in each case are described and presented. The absorbed dose in health human organs and tissues are simulated with two recommended programs WinAct and IDAC 2.1(Internal Dose Assessment by Computer) software. The distribution of absorbed dose in the main organs nearly the same with different in the value for the ionic form and 177Lu-MDP. The absorption in the case of ionic form is high. The distribution is completely change while 177Lu-MAb is used. The most absorbed dose fraction goes to spleen and liver unlike bone surface absorb nearly 50 % of dose. © 2019 Author(s)

The dynamics of the cellular composition of urine sediment in conditions of an artificial bladder

The evaluation of the urine cytological profile in the dynamics of adaptation of the orthotopic bladder to the functional properties of the urinary reservoir and determination of the connection between the cellular composition of the urine with the functional role of the formed from the intestinal fragment neocyst in experimental conditions and in humans. The material in experimental study were the results of a cytological study of the urine sediment obtained from 21 female pigs (mini-pigs). The portion of urine had received in experimental animals one month after orthotopic ileocystoplasty, 6 months and 1 year later and prepared as smear from the resulting precipitate. The level of lymphocytes, neutrophils, erythrocytes, as well as the superficial, intermediate and basal epitheliocytes evaluated during study. An analysis of the cell composition of centrifugal smears from the neocyst were performed in 21 patients with bladder cancer undergoing cystectomy and the formation of an orthotopic bladder, at various periods after surgery, from 3 months to 5 years. The preparation of a centrifugal sediment and the subsequent production of smears carried out as well as experimental animals

Attachment rate characteristics of different wide used aerosol sources in indoor air

In this work, six different aerosol sources, used in everyday life, were investigated to analyze parameters such as concentration, size distributions, and dynamics: regular and electronic cigarettes, incense, candles, mosquito coils, and cooking. During the experiments, the aerosol particle count ranged from 200 to 2·105 cm−3. The number, mass, and specific surface area of the aerosol size distributions were measured by a Model 2702 M diffusion aerosol spectrometer (DAS) with a range of 5 nm to 10 μm. The attachment rate of radon decay products to aerosol particles is calculated depending on their size distribution/ The use of household sources of aerosols (heat treatment of food, smoking, candles, etc.) result in an increase in the concentration of aerosol particles by more than an order of magnitude, mainly due to the generation of ultrafine aerosols with number median diameter 64–92 nm and GSD 1.45–1.84. The mass distribution is dominated by particles with a distribution maximum in the range of 2–5 μm. The attachment of radon decay products to aerosols is associated with ultrafine particles with diameter < 200 nm. The median diameter of the rate of attachment to aerosols is 130 nm. © 2021, Springer Nature Switzerland AG