Application of Broadband Microwave Near-Field Sensors for Glucose Monitoring in Biological Media

The paper presents results of numerical simulation and experimental testing of a microwave sensor for non-invasive glucose monitoring. The sensor represents a conical horn with a conical conductor inside expanding toward the horn aperture. Such a sensor has a significantly wider passband in comparison with sensors of other designs. It is essential that the sensor geometry provides formation of an extended near-field zone with high electric field strength near the sensor aperture. A clear relationship between the dielectric permittivity of the phantom biological tissue and the frequency dependence of the parameter S11 of the sensor is observed at frequencies in the range from 1.4 to 1.7 GHz. This circumstance can be used to develop a procedure for measuring the glucose level in blood that correlates with the parameter S11 of the sensor. From the viewpoint of monitoring of the glucose content in blood, the most convenient body sensor location is on the hands or feet, in particular, wrists.

IRRADIATOR WITH MINIMAL LOSSES OF PARABOLIC ANTENNA FOR RADIO MONITORING SYSTEMS OF INFORMATION CHANNELS OF RADIO RELAY COMMUNICATION LINES

Analysis of the experience of modern struggle shows that the success of combat missions to sone extent depends on the timely detection of information from communication channels, in particular, radio relay communication lines. Increasing the detection range of the radio monitoring station can be achieved by using a mirror parabolic antenna with a radiation in the form of a conical horn with low losses due to the use of a matching device. The constructive decisions of matching devices are analysed and it is determined that most of them are resonant. The substantiation and selection of the design of the dielectric transformer with the length ( – wavelength in a round waveguide, m) for coordination of the conical horn irradiator in the whole band of its operating frequencies for the wave type is carried out. To achieve the goal, the methods of antenna theories and electrodynamics were used, in particular the theory of long lines. A mathematical apparatus has been developed for calculating the parameters of a dielectric transformer (the length ). It is stated that its impedance must be equal to the modulus of load resistance. The calculation of the value of the active transformed resistance according to the formula (10) always gives a positive value of the input resistance, the value of which is greater the greater the reactive load reactance. The reliability of the obtained formulas is confirmed by the convergence of units and graphs of dependences of the changes of the outer radius of the coaxial power line (its impedance), as well as the thickness and place of inclusion on the matching dielectric transformer . The practical significance of the research results lies in the possibility of improving the matching of a horn antenna based on a circular waveguide in the range of its operating frequencies for a certain type of wave.

Carbon Nanohorns as Effective Nanotherapeutics in Cancer Therapy

Different carbon nanostructures have been explored as functional materials for the development of effective nanomaterials in cancer treatment applications. This review mainly aims to discuss the features, either strength or weakness, of carbon nanohorn (CNH), carbon conical horn-shaped nanostructures of sp2 carbon atoms. The interest for these materials arises from their ability to couple the clinically relevant properties of carbon nanomaterials as drug carriers with the negligible toxicity described in vivo. Here, we offer a comprehensive overview of the recent advances in the use of CNH in cancer treatments, underlining the benefits of each functionalization route and approach, as well as the biological performances of either loaded and unloaded materials, while discussing the importance of delivery devices.