An Overview of X-ray Photon Counting Spectral Imaging (x-CSI) with a Focus on Gold Nanoparticle Quantification in Oncology

This review article offers an overview of the differences between traditional energy integrating (EI) X-ray imaging and the new technique of X-ray photon counting spectral imaging (x-CSI). The review is motivated by the need to image gold nanoparticles (AuNP) in vivo if they are to be used clinically to deliver a radiotherapy dose-enhancing effect (RDEE). The aim of this work is to familiarise the reader with x-CSI as a technique and to draw attention to how this technique will need to develop to be of clinical use for the described oncological applications. This article covers the conceptual differences between x-CSI and EI approaches, the advantages of x-CSI, constraints on x-CSI system design, and the achievements of x-CSI in AuNP quantification. The results of the review show there are still approximately two orders of magnitude between the AuNP concentrations used in RDEE applications and the demonstrated detection limits of x-CSI. Two approaches to overcome this were suggested: changing AuNP design or changing x-CSI system design. Optimal system parameters for AuNP detection and general spectral performance as determined by simulation studies were different to those used in the current x-CSI systems, indicating potential gains that may be made with this approach.

Analysis of FBMC Waveform for 5G Network Based Smart Hospitals

Nowadays, many prevalent frameworks for medical care have been projected, studied, and implemented. The load and challenges of traditional hospitals are increasing daily, leading to inefficient service in the health system. Smart hospitals based on advanced techniques play a crucial part in advancing the health services of rural people. It spares the time and money involved in travel, and patient medical reports can be shared instantly with the experts regardless of geographical constraints. Currently, the role of technology in hospitals is limited due to various restrictions, such as the obtainability of a high spectrum, low latency, and high-speed network. In this paper, we focused on the implementation of an advanced waveform with high spectral performance. Filer Bank Multi-Carrier (FBMC) is considered a strong contender for the upcoming 5G-centered smart hospitals due to its high data rate, no leakage of the spectrum, and less sensitivity to frequency error. In addition, a comparison of the spectral utilization of orthogonal frequency division multiplexing (OFDM) and FBMC in terms of bit error rate (BER), peak power (PP), power spectral density (PSD), noise-PSD, capacity and magnitude, and phase response is illustrated. Numerical results show that the FBMC achieved a throughput gain of 1 dB and its spectral performance is better than the OFDM; hence, it is a better choice for the proposed application compared to the current standard OFDM.

Monte Carlo transmission line modelling of multilayer optical coatings for performance sensitivity of exoplanet spectroscopy

<p>Multilayer optical coatings are widely used on the surface of optical components to enhance the transmittance of light in certain spectral regions while reducing it in other regions. Discrepancies between the measured and predicted spectral performance of optical components with such coatings can primarily be attributed to deposition errors and uncertainties in the refractive indices of the materials used for these coatings. Our simulation uses two-dimensional transmission line modelling to evaluate the transmittance of light at a given angle of incidence through multilayer coatings deposited on a substrate material. We perform a number of Monte Carlo simulations to obtain statistical information about the tolerance of the coating performance to systematic and random uncertainties in deposition thickness, refractive index and operating temperature. We present the posterior distributions of the deviations from the nominal performance that result from the propagation of each of these uncertainties for a number of hypothetical scenarios. We find that these uncertainties have the potential to cause significant differences between the designed and achieved performance. Our results indicate that the sensitivity of each layer to the various sources of uncertainties can vary on a case-by-case basis. With the aid of accurate manufacturing recipes and uncertainty amplitudes from commercial manufacturers, this simulation can provide a proficient tool to predict variations in the performance of multilayer optical coatings used in exoplanet spectroscopy.</p>

Technical specifications and spectral performance characteristics of dispersion flattened fiber (DFF) in optical fiber systems

This work has clarified the technical specifications and spectral performance characteristics of dispersion flattened fiber (DFF) in optical fiber systems. Effective nonlinear refractive index and first, second order polarization mode dispersion against spectral wavelength with fiber length of 1000 m and coupling length of 20 m are simulated and demonstrated. Total DFF fiber losses/dispersion performance parameters are investigated and simulated by using OptiFiber simulation. Zero DFF fiber dispersion and its dispersion slope are demonstrated clearly in details. The dominant modes and the cutoff data theoretical values based these modes for the proposed DFF fiber is determined and simulated in a clear manner.

A Theoretical Perspective of the Photochemical Potential in the Spectral Performance of Photovoltaic Cells

We present a novel theoretical approach to the problem of light energy conversion in thermostated semiconductor junctions. Using the classical model of a two-level atom, we deduced formulas for the spectral response and the quantum efficiency in terms of the input photons’ non-zero chemical potential. We also calculated the spectral entropy production and the global efficiency parameter in the thermodynamic limit. The heat transferred to the thermostat results in a dissipative loss that appreciably controls the spectral quantities’ behavior and, therefore, the cell’s performance. The application of the obtained formulas to data extracted from photovoltaic cells enabled us to accurately interpolate experimental data for the spectral response and the quantum efficiency of cells based on Si-, GaAs, and CdTe, among others.