16 research outputs found
Effect of luminescence transport through adipose tissue on measurement of tissue temperature by using ZnCdS nanothermometers
The spectra of luminescence of ZnCdS nanoparticles (ZnCdS NPs) were measured and analyzed in a wide temperature range: from room to human body and further to a hyperthermic temperature resulting in tissue morphology change. The results show that the signal of luminescence of ZnCdS NPs placed within the tissue is reasonably good sensitive to temperature change and accompanied by phase transitions of lipid structures of adipose tissue. It is shown that the presence of a phase transition in adipose tissue upon its heating (polymorphic transformations of lipids) leads to a nonmonotonic temperature dependence of the intensity of luminescence for the nanoparticles introduced into adipose tissue. This is due to a change in the light scattering by the tissue. The light scattering of adipose tissue greatly distorts the results of temperature measurements. The application of these nanoparticles is possible for temperature measurements in very thin or weakly scattering samples
Temperature sensing of adipose tissue heating with the luminescent upconversion nanoparticles as nanothermometer: In vitro study
The luminescence spectra of upconversion nanoparticles (UCNPs) imbedded in fat tissue were measured in a wide temperature range, from room to human body and further to hyperthermic temperatures. The two types of synthesized UCNP [NaYF4:Yb3+, Er3+] specimens, namely, powdered as-is and embedded into polymer film, were used. The results show that the luminescence of UCNPs placed under the adipose tissue layer is reasonably good sensitive to temperature change and reflects phase transitions of lipids in tissue cells. The most likely, multiple phase transitions are associated with the different components of fat cells such as phospholipids of cell membrane and lipids of fat droplets. In the course of fat cell heating, lipids of fat droplet first transit from a crystalline form to a liquid crystal form and then to a liquid form, which is characterized by much less scattering. The phase transitions of lipids were observed as the changes of the slope of the temperature dependence of UCNP luminescence intensity. The obtained results confirm a high sensitivity of the luminescent UCNPs to the temperature variations within tissues and show a strong potential for providing a controllable tissue thermolysis
Delivery and reveal of localization of upconversion luminescent microparticles and quantum dots in the skin in vivo by fractional laser microablation, multimodal imaging, and optical clearing
Delivery and spatial localization of upconversion luminescent microparticles [Y 2 O 3 ;Yb, Er] (mean size ~1.6 μm) and quantum dots (QDs) (CuInS 2 ZnS nanoparticles coated with polyethylene glycol-based amphiphilic polymer, mean size ~20 nm) inside rat skin was studied in vivo using a multimodal optical imaging approach. The particles were embedded into the skin dermis to the depth from 300 to 500 μm through microchannels performed by fractional laser microablation. Low-frequency ultrasound was applied to enhance penetration of the particles into the skin. Visualization of the particles was revealed using a combination of luminescent spectroscopy, optical coherence tomography, confocal microscopy, and histochemical analysis. Optical clearing was used to enhance the image contrast of the luminescent signal from the particles. It was demonstrated that the penetration depth of particles depends on their size, resulting in a different detection time interval (days) of the luminescent signal from microparticles and QDs inside the rat skin in vivo. We show that luminescent signal from the upconversion microparticles and QDs was detected after the particle delivery into the rat skin in vivo during eighth and fourth days, respectively. We hypothesize that the upconversion microparticles have created a long-time depot localized in the laser-created channels, as the QDs spread over the surrounding tissues
Modernization of transport infrastructure for the development of pedestrian and bicycle paths on the example of a large city in Russia
The article examines the promising directions of the existing concept of the Russian Federation on bicycle transport. Unlike Western countries, bicycle transport in Russia is only gaining its popularity and many people who preferred cars, in the spring-summer time, give their preference to bicycles and scooters. The study proves the relevance of the issue at stake, justifies the modernization of the existing transport frame of the territory and the need for its improvement with the help of a new project that will create comfortable conditions for movement and will be very significant for the city. The priority development of the territory is considered through the construction of a new pedestrian and bicycle transport bridge. The authors have developed proposals for solving the problem for comfortable movement of pedestrians and cyclists, as well as for people with limited mobility. The experience of foreign countries in creating projects of transport infrastructure for walking and cycling, which allows creating the most comfortable conditions for movement around the city, is generalized
The concept of inter-settlement territory in the Russian Federation
The article explores the question of the concept of inter-settlement territory. Such a territory, namely the concept of such a territory in the Russian Federation, appeared relatively recently. The authors studied the prospects for the development of settlements (urban, rural) through the use of the inter-settlement territory, which is mainly formed on agricultural lands. A generalized analysis of scientific methods and approaches of the organization of management in settlements and in inter-settlement territories are considered, the problems of using such a territory are identified and proposals are developed to solve the identified problems of the legal status of an inter-settlement territory
Ecological culture: sociocultural and legal aspects
The study’s objective is to identify factors that can have a productive and positive impact on the formation of environmental culture. The authors use an interdisciplinary approach in the study. Thus, the methods of system analysis (methods of integration, convergence, structurization, optimization, etc.) focus on a comprehensive study of contemporary problems of ecological culture. Applying the methodology of legal taxonomy allows outlining the basic principles contributing to the level of ecological culture. Among the special methods, the method of ecologization is of particular importance in the study. The results of the study were the identification of a complex of factors. There are positive and negative factors among them. Negative factors are due to the lack of environmental values in people’s minds, the state’s perception of environmental relations as insignificant or secondary in the life of society, the rejection of innovative concepts of ecologization of economic activity, etc. Positive factors include the effectiveness of the principles of environmental law, the development of a system of environmental education of citizens, education of environmental responsibility, the collective search for adequate solutions to address the growing environmental risks, etc. The novelty of the work lies in the statement of the problem, which is that the formation of environmental culture is of paramount importance for sustainable development and environmental security of states and the entire world community
Temperature sensing of adipose tissue heating with the luminescent upconversion nanoparticles as nanothermometer: In vitro study
The luminescence spectra of upconversion nanoparticles (UCNPs) imbedded in fat tissue were measured in a wide temperature range, from room to human body and further to hyperthermic temperatures. The two types of synthesized UCNP [NaYF4:Yb3+, Er3+] specimens, namely, powdered as-is and embedded into polymer film, were used. The results show that the luminescence of UCNPs placed under the adipose tissue layer is reasonably good sensitive to temperature change and reflects phase transitions of lipids in tissue cells. The most likely, multiple phase transitions are associated with the different components of fat cells such as phospholipids of cell membrane and lipids of fat droplets. In the course of fat cell heating, lipids of fat droplet first transit from a crystalline form to a liquid crystal form and then to a liquid form, which is characterized by much less scattering. The phase transitions of lipids were observed as the changes of the slope of the temperature dependence of UCNP luminescence intensity. The obtained results confirm a high sensitivity of the luminescent UCNPs to the temperature variations within tissues and show a strong potential for providing a controllable tissue thermolysis
Comparison of temperature sensing of the luminescent upconversion and ZnCdS nanoparticles
The luminescence spectra of upconversion nanoparticles (UCNPs) and ZnCdS nanoparticles (ZnCdSNPs) were measured and analyzed in a wide temperature range: from room to human body and further to a hyperthermic temperature resulting in tissue morphology change. The results show that the luminescence signal of UCNPs and ZnCdSNPs placed within the tissue is reasonably good sensitive to temperature change and accompanied by phase transitions of lipid structures of adipose tissue. The most likely that the multiple phase transitions are associated with the different components of fat cells, such as phospholipids of cell membrane and lipids of fat droplets. In the course of fat cell heating, lipids of fat droplet first transit from a crystalline form to a liquid crystal form and then to a liquid form, which is characterized by much less scattering. The results of phase transitions of lipids were observed as the changes in the slope of the temperature dependence of the intensity of luminescence of the film with nanoparticles embedded into tissue. The obtained results confirm a high sensitivity of the luminescent UCNPs and ZnCdSNPs to the temperature variations within thin tissue samples and show a strong potential for the controllable tissue thermolysis