In photodynamic therapy, light is absorbed by a therapy agent (photosensitizer) to generate reactive oxygen, which then locally kills diseased cells. Here, we report a new form of photodynamic ...therapy in which nonlinear optical interactions of near-infrared laser radiation with a biological medium in situ produce light that falls within the absorption band of the photosensitizer. The use of near-infrared radiation, followed by upconversion to visible or ultraviolet light, provides deep tissue penetration, thus overcoming a major hurdle in treatment. By modelling and experiment, we demonstrate activation of a known photosensitizer, chlorin e6, by in situ nonlinear optical upconversion of near-infrared laser radiation using second-harmonic generation in collagen and four-wave mixing, including coherent anti-Stokes Raman scattering, produced by cellular biomolecules. The introduction of coherent anti-Stokes Raman scattering/four-wave mixing to photodynamic therapy in vitro increases the efficiency by a factor of two compared to two-photon photodynamic therapy alone, while second-harmonic generation provides a fivefold increase.
Using laser tweezers, we study colloidal interactions of solid microspheres in the nematic bulk caused by elastic distortions around the particles with tangential surface anchoring. The interactions ...overcome the Brownian motion when the interparticle separation r-->p is less than 3 particle diameters. The particles attract when the angle theta between r-->p and the uniform far-field director n0 is between 0 degrees and approximately 70 degrees and repel when 75 degrees <or approximately theta<or=90 degrees. The particles aggregate in chains directed at approximately 30 degrees to n0 and, at higher concentrations, form complex kinetically trapped structures.
Soluble B7-H3 in Colorectal Cancer Kovaleva, O. V.; Gratchev, A. N.; Sokolov, N. Yu ...
Bulletin of experimental biology and medicine,
11/2023, Letnik:
176, Številka:
1
Journal Article
Recenzirano
We present the results of comparative ELISA of the concentration of soluble form of immunity checkpoint B7-H3 (sB7-H3) in the serum of patients with colorectal cancer (CRC) at different stages before ...treatment and healthy control donors. The analysis revealed a statistically significant difference between the median levels of sB7-H3 in the blood serum of CRC patients (19.66 ng/ml) and healthy donors (16.76 ng/ml) (
p
=0.0025). ROC analysis showed 62.9% sensitivity and 56.7% specificity for CRC patients (cut-off 17.62 ng/ml;
p
=0.0028). An association of sB7-H3 levels with tumor progression was revealed. We demonstrated that sB7-H3 levels were significantly lower in patients with regional metastases than in patients without metastases (
p
=0.039) and that sB7-H3 concentration tends to decrease at the late stages of the disease. Thus, high serum level of sB7-H3 in CRC patients can be a favorable prognostic factor in future.
Rated definition of fuel consumption by vehicles becomes the new direction of improvement of transportation processes. Calculations of daily fuel consumption by bus PAZ with the diesel engine used on ...city routes of Nizhny Novgorod with use of specifications of a definition technique of specific fuel consumption depending on extent application of engine power are executed. Results are compared with the existing normative indicators.
The existing methods of theoretical definition of automobile fuel consumption are not always correct. In particular, when we calculate fuel efficiency of the car equipped by the diesel engine, we ...receive some paradoxical result: the lowest fuel consumption appears to be during the movement on low gears in the gearbox. The present article tries to analyze this situation as well as to bring some mathematically proved calculations necessary to evaluate correction coefficients of the engine fuel consumption from degree of using engine power, which gives significant improving of calculation accuracy, especially for automobiles with diesel engines. Special tables for fast determination of these coefficients value are provided.
Current status of tokamak T-15MD Khvostenko, P.P.; Anashkin, I.O.; Bondarchuk, E.N. ...
Fusion engineering and design,
March 2021, 2021-03-00, 20210301, Letnik:
164
Journal Article
Recenzirano
•T-15MD project is aimed at obtaining a database for creating a thermonuclear neutron source for atomic energy needs.•Magnet system of T-15MD will confine the hot plasma in the divertor ...configuration.•Toroidal magnetic field at the plasma axis is 2 T, plasma current is 2 MA.•Preparation to physical start-up of tokamak T-15MD is completed.•T-15MD should begin operation in 2021.
At the present time, the preparation to physical start-up of tokamak T-15MD is completed in the National Research Center “Kurchatov Institute”. The main parameters of T-15MD are: R = 1.48 m, a = 0.67 m, B = 2.0 T, Ipl = 2.0 MA. The magnet system is capable to maintain without overheating (more 60 °C) the plasma current of 2 MA for 4 s, 1 MA for 20 s, 700 kA for 40 s, 500 kA for 80 s, 300 kA for 160 s and 250 kA for 400 s. Plasma current drive can be maintained either by injection of fast neutrals or by electron cyclotron (EC)-, ion cyclotron (IC)- and low hybrid (LH) - waves. In August 2019 the electromagnetic system, consisting of TF and PF coils, together with vacuum vessel have been assembled in experimental hall. Power supply system of Tokamak T-15MD includes: two substations 110/10 kV, two substations 10/0.83 kV, thyristor convertors and different equipment. Total power consumption during the pulse with plasma current 2 MA and additional plasma heating of 20 MW will consist of 300 MVA. Power supply system is in the commissioning. Tokamak T-15MD will be operate using the information and control system. All the information and control system equipment, required for the implementation of physical start-up of tokamak T-15MD, is available. For plasma control the 250 different electromagnetic probes are installed inside vacuum vessel. The gyrotron with frequency 82.6 GHz and power of 1 MW will be used for pre-ionization.
The dynamics of tree height in Scots pine (
Pinus sylvestris
L.) of different origin have been studied in provenance trials on sandy and loam soils in Central Siberia. Plots with different soil types ...occur in one geographical location in the Boguchansky District of Krasnoyarsk krai, Russia. Thus, they are characterized by similar climatic conditions. At the trial sites, pine climatype progeny has a different adaptive reaction on the soil conditions and other environmental factors. The differentiation of Scots pine climatypes according to the mean height is shown. Perspective climatypes of the Scots pine are distinguished based on its growth dynamics.
Composite films and nonwoven mats of the poly-3-hydroxybutyrate and chitosan natural polymers were prepared and investigated. DSC and FTIR techniques were used to confirm that P(3HB) blending with ...chitosan resulted in a decrease in P(3HB) crystallinity to 47% and 62% in the films and nonwoven mats, respectively. Scanning electron microscopy showed that addition of chitosan induced changes in the surface morphology of the composite films and a reduction in the diameter of ultrafine fibers in the nonwoven mats from 800 nm to 460 nm. The values of water contact angle for films (53°) and nonwoven mats (50.6°) suggested that chitosan enhanced hydrophilic properties and moisture absorption capacity of the composite materials. On the other hand, P(3HB) showed its reinforcing ability and improved the physical/mechanical properties of chitosan. The work included studies of in vitro biodegradation of the composite specimens and their ability to maintain cell growth and attachment in NIH 3T3 fibroblast culture.
•Composite films and nonwoven mats of the P(3HB) and chitosan natural polymers were prepared and investigated.•P(3HB) blending with chitosan resulted in a decrease in P(3HB) crystallinity and the melting point.•The introduction of chitosan into the P (3HB) matrix increased the hydrophilicity of the composites and the adhesion of fibroblasts.
Using electron-microscopy methods, the effect of the nature of polymer–colloidal drilling fluids on the pore space in carbonate reservoirs of an oil-and-gas-condensate field is studied. It is shown ...that the impact of polymers included in the composition of drilling fluids changes the surface of the pore space of rocks. This has an effect on the technology of developing oil fields and the intensification of oil production. At the same time, the properties of the samples change because of the deposition of polymer components in the pore space of the rock. This must be taken into account when conducting petrophysical studies of specimens, as well as in geophysical investigation of the bottomhole zone by methods with a small radius of investigation. The results of morphological electron-microscopy studies of the pore space of rocks after the impact of polymer–colloidal drilling fluids are given. Polymer films formed from drilling-fluid components are studied. It is established that the change in the wettability of the pore space after drilling horizontal wells is associated with the formation of a polymer film on carbonate crystals. The thickness of this film is 60–200 µm in the studied specimens when measured by the direct method. It is noted that these changes can lead to errors in determining the petrophysical properties in the future.
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