Structural and Magnetic Properties of Iron Oxide Nanoparticles in Shells of Hollow Microcapsules Designed for Biomedical Applications

The functional hollow biodegradable microcapsules modified with the maghemite γ-Fe2O3 nanoparticles and the hollow spherical CoFe2O4/SiO2 nanocomposites were synthesized. Mössbauer spectroscopy data reveal that the main part maghemite nanoparticles have evident superparamagnetic behavior which is retained up to room temperature. This allows directing the microcapsules by an external magnetic field, which is very important for the problem of target drug delivery. On the other hand, the hollow spherical CoFe2O4/SiO2 nanocomposites with the small size particles do not show superparamagnetic behavior, but transit from magnetic to paramagnetic state by jump-like magnetic transition of the first order. This effect is a specific property of the magnetic nanoparticles isolated by an inert material. The method of synthesis can be modified with various bioligands on the silane surface, and such materials can have great prospects for use in diagnostics and bio-separation

Some morphological factors of resistance of the bronchial wall to the development of chronic obstructive lung disease in smoking individuals

According to current epidemiological studies, chronic obstructive pulmonary disease (COPD) develops in only 15-20 % of smokers. This suggests that exposure to tobacco smoke is just a trigger of the pathological process, and other pathophysiological factors play a key role in the development of COPD. The aim of the study was to perform morphological analysis of bronchial mucosa features in smokers with and without chronic obstructive pulmonary disease.Material and research methods. Morphological and electron-microscopic analysis of biopsy samples of the bronchial mucosa of smoking patients with (n = 40) and without (n = 30) chronic obstructive pulmonary disease was carried out. The study involved men (80.2 % of men) and women aged 42 to 67 years (62.3 ± 2.24 years) with smoking experience of more than 20 years and smoking intensity of 20-45 pack-years. In the main group was a verified diagnosis of COPD. All patients of the studied groups underwent morphological, morphometric counting of bulk densities of various types of epithelial cells and structures of their lamina propria of the bronchial mucosa, as well as the density of inflammatory infiltrate and various cell populations, immunohistochemical (typing of CD4- and CD8positive lymphocytes, expression of transforming growth factor β1 receptors) and electron microscopic analysis of bronchobioptates.Results and discussion. Smokers without chronic obstructive pulmonary disease develop exudative inflammation, which does not violate the structural architectonics of the epithelial layer, but causes activation of proteinsynthetic and energy processes in the epithelial cells of the bronchial wall. With prolonged exposure to tobacco smoke associated with the development of chronic obstructive pulmonary disease, chronic neutrophilic inflammation forms in the bronchial mucosa, leading to a violation of the functional morphology of the vessels and epithelial cells of the bronchial mucosa, followed by remodeling of the bronchial wall

Полиэлектролитные микрокапсулы, модифицированные наноразмерным диоксидом титана, для адресной доставки лекарственных средств

Polyelectrolyte microcapsules composed of CaCO3-core and shell polydiallyldimethylammonium polistirolsufonatpolystyrenesulfonate, were obtained by Layer-by-Layer-method. They were modified with nanoscale titanium dioxide with rutile structure and commercial Degussa P25 and Hombikat UV-100. Besides it has been shown that the sample Hombikat UV-100 is better included in the capsule shell because of a largerspecific surface area and the presence of hydrated component in composition of sample. Resistance to UVradiation was tested on the capsules modified with Degussa P25. It has been established that the modification takes place only in the case of "thick" shells with the number of bilayers being x=8. In the case of shells with x=4 there is a destruction of polyelectrolyte capsules during modification. It has been found that the degree of modification of capsules by nanosizedtitanium dioxide depends on the shell thickness (value x) as well as on the surface of nanoscale titanium dioxide samplesМетодом послойной адсорбции получены полиэлектролитные микрокапсулы, состоящие из CaCO3-ядра и полидиаллилдиметиламмноний-полистиролсульфонатной оболочки, модифицированной наноразмерным диоксидом титана со структурой рутила, а также коммерческими образцами Degussa P 25 и Hombikat UV-100. Показано, что образец Hombikat UV-100 включается в оболочку капсулы на порядок лучше, причем микрокапсулы с Degussa P 25 разрушаются под действием УФ-излучения, что делает возможным использование данной системы в адресной доставке лекарств

Feasibility studies of time-like proton electromagnetic form factors at PANDA at FAIR

Simulation results for future measurements of electromagnetic proton form factors at \PANDA (FAIR) within the PandaRoot software framework are reported. The statistical precision with which the proton form factors can be determined is estimated. The signal channel $\bar p p \to e^+ e^-$ is studied on the basis of two different but consistent procedures. The suppression of the main background channel, $\textit{i.e.}$ $\bar p p \to \pi^+ \pi^-$, is studied. Furthermore, the background versus signal efficiency, statistical and systematical uncertainties on the extracted proton form factors are evaluated using two different procedures. The results are consistent with those of a previous simulation study using an older, simplified framework. However, a slightly better precision is achieved in the PandaRoot study in a large range of momentum transfer, assuming the nominal beam conditions and detector performance

Feasibility studies for the measurement of time-like proton electromagnetic form factors from p¯ p→ μ+μ- at P ¯ ANDA at FAIR

This paper reports on Monte Carlo simulation results for future measurements of the moduli of time-like proton electromagnetic form factors, | GE| and | GM| , using the p¯ p→ μ+μ- reaction at P ¯ ANDA (FAIR). The electromagnetic form factors are fundamental quantities parameterizing the electric and magnetic structure of hadrons. This work estimates the statistical and total accuracy with which the form factors can be measured at P ¯ ANDA , using an analysis of simulated data within the PandaRoot software framework. The most crucial background channel is p¯ p→ π+π-, due to the very similar behavior of muons and pions in the detector. The suppression factors are evaluated for this and all other relevant background channels at different values of antiproton beam momentum. The signal/background separation is based on a multivariate analysis, using the Boosted Decision Trees method. An expected background subtraction is included in this study, based on realistic angular distributions of the background contribution. Systematic uncertainties are considered and the relative total uncertainties of the form factor measurements are presented

Study of doubly strange systems using stored antiprotons

Bound nuclear systems with two units of strangeness are still poorly known despite their importance for many strong interaction phenomena. Stored antiprotons beams in the GeV range represent an unparalleled factory for various hyperon-antihyperon pairs. Their outstanding large production probability in antiproton collisions will open the floodgates for a series of new studies of systems which contain two or even more units of strangeness at the P‾ANDA experiment at FAIR. For the first time, high resolution γ-spectroscopy of doubly strange ΛΛ-hypernuclei will be performed, thus complementing measurements of ground state decays of ΛΛ-hypernuclei at J-PARC or possible decays of particle unstable hypernuclei in heavy ion reactions. High resolution spectroscopy of multistrange Ξ−-atoms will be feasible and even the production of Ω−-atoms will be within reach. The latter might open the door to the |S|=3 world in strangeness nuclear physics, by the study of the hadronic Ω−-nucleus interaction. For the first time it will be possible to study the behavior of Ξ‾+ in nuclear systems under well controlled conditions

The Eurasian Modern Pollen Database (EMPD), version 2

The Eurasian (née European) Modern Pollen Database (EMPD) was established in 2013 to provide a public database of high-quality modern pollen surface samples to help support studies of past climate, land cover, and land use using fossil pollen. The EMPD is part of, and complementary to, the European Pollen Database (EPD) which contains data on fossil pollen found in Late Quaternary sedimentary archives throughout the Eurasian region. The EPD is in turn part of the rapidly growing Neotoma database, which is now the primary home for global palaeoecological data. This paper describes version 2 of the EMPD in which the number of samples held in the database has been increased by 60 % from 4826 to 8134. Much of the improvement in data coverage has come from northern Asia, and the database has consequently been renamed the Eurasian Modern Pollen Database to reflect this geographical enlargement. The EMPD can be viewed online using a dedicated map-based viewer at https://empd2.github.io and downloaded in a variety of file formats at https://doi.pangaea.de/10.1594/PANGAEA.909130 (Chevalier et al., 2019)Swiss National Science Foundation | Ref. 200021_16959