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With the advances in nanotechnology, novel nanosensing technologies can play a pivotal role in today’s society. Plasmonic sensing has demonstrated unprecedented detection reliability and resolution in a very compact form factor. Traditional plasmonic sensors leverage biofunctionalized metallic grating structures whose frequency response in transmission or reflection changes according to the presence of targeted biomarkers. However, these sensing setups require bulky measurement equipment to couple light to and from sensors for excitation and detection. In parallel, for over a decade, the nanoscale electromagnetic communication community has been leveraging plasmonic structures to transmit information at the nanoscale efficiently. By combining the two realms, this paper proposes the concept of joint nanoscale communication and bio-sensing systems enabled by plasmonic sensing nanoantennas. Sensing nanonodes can communicate from nanonode to nanonode for intra-body networks and from nanonode to a wearable device which, by leveraging the edge, can process and transmit the sensing information to the cloud, resulting in accurate diagnosis and reduced load on the medical testing infrastructure. First, we model the changes in the frequency response of a biofunctionalized plasmonic nanoantenna when exposed to different biomarkers. Then, we propose a chirp-spread spectrum excitation and detection system to enable simultaneous communication and sensing at the nanoscale. We present a data-driven human tissue model for communication through human tissue. We also present numerical results to demonstrate the performance of the proposed system. [ABSTRACT FROM AUTHOR]

Recent Brain-Machine Interfaces have moved towards miniature devices that can be seamlessly integrated into the cortex. In this paper, we propose communication between miniature devices using light. A number of challenges exist using nanoscale light-based communication and this includes diffraction, scattering, and absorption, where these properties result from the tissue medium as well as the cell’s geometry. Under these effects, the paper analyses the propagation path loss and geometrical gain, channel impulse and frequency response through a line of neurons with different shapes. Our study found that the light attenuation depends on the propagation path loss and geometrical gain, while the channel response is highly dependent on the quantity of cells along the path. Additionally, the optical properties of the medium impact the time delay at the receiver and the width and the location of the detectors. Simulations were conducted for cells that are lined horizontally up to a distance of $450~\mu \text{m}$ using light wavelength of 456 nm and different neuron densities (men’s neocortex (25924(±15110) /mm3) and women’s (27589(±16854) /mm3)). Based on the simulations, we found that spherical cells attenuate approximately 20% of the transmitted power compared to the fusiform and pyramidal cells (35% and 65%, respectively). [ABSTRACT FROM AUTHOR]

In recent years, digital multimedia including image, audio, and video are extended to quantum computation and quantum networks. Consequently, copyright protection of digital multimedia in quantum networks becomes a significant issue. As an important security technology, quantum watermarking is an appropriate solution, which embeds copyright information into the carrier signal. This work presents an enhanced least significant bit (LSB) based audio watermarking using reflected gray code. In the presented scheme, the watermark image is first scrambled using a new scrambling method presented in this paper, which modifies pixel values for scrambling instead of changing pixel positions. The scrambled image is then converted into a qubit sequence to comply with one-dimension audio signal, and the qubits are embedded into carrier quantum audio signal using an embedding key. In embedding phase, every four low qubit of target audio sample replaced with their nearest even or odd number in reflected gray code, based on the value of embedded qubit. For every procedure of the proposed scheme, the quantum circuit and complexity analysis is presented. Experimental results prove that the proposed scheme has good transparency, capacity and security. [ABSTRACT FROM AUTHOR]

With the advancement of synthetic biology, several new tools have been conceptualized over the years as alternative treatments for current medical procedures. As part of this work, we investigate how synthetically engineered neurons can operate as digital logic gates that can be used towards bio-computing inside the brain and its impact on epileptic seizure-like behaviour. We quantify the accuracy of logic gates under high firing rates amid a network of neurons and by how much it can smooth out uncontrolled neuronal firings. To test the efficacy of our method, simulations composed of computational models of neurons connected in a structure that represents a logic gate are performed. Our simulations demonstrate the accuracy of performing the correct logic operation, and how specific properties such as the firing rate can play an important role in the accuracy. As part of the analysis, the mean squared error is used to quantify the quality of our proposed model and predict the accurate operation of a gate based on different sampling frequencies. As an application, the logic gates were used to smooth out epileptic seizure-like activity in a biological neuronal network, where the results demonstrated the effectiveness of reducing its mean firing rate. Our proposed system has the potential to be used in future approaches to treating neurological conditions in the brain. [ABSTRACT FROM AUTHOR]

Miniaturization of implantable devices is an important challenge for future brain–computer interface applications, and in particular for achieving precise neuron stimulation. For stimulation that utilizes light, i.e., optogenetics, the light propagation behavior and interaction at the nanoscale with elements within the neuron is an important factor that needs to be considered when designing the device. This paper analyzes the effect of light behavior for a single neuron stimulation and focuses on the impact from different cell shapes. Based on the Mie scattering theory, the paper analyzes how the shape of the soma and the nucleus contributes to the focusing effect resulting in an intensity increase, which ensures that neurons can assist in transferring light through the tissue toward the target cells. At the same time, this intensity increase can in turn also stimulate neighboring cells leading to interference within the neural circuits. This paper also analyzes the ideal placements of the device with respect to the angle and position within the cortex that can enable axonal biophoton communications, which can contain light within the cell to avoid the interference. [ABSTRACT FROM AUTHOR]

Quorum sensing (QS) is used to describe the communication between bacterial cells, whereby a coordinated population response is controlled through the synthesis, accumulation and subsequent sensing of specific diffusible chemical signals called autoinducers, enabling a cluster of bacteria to regulate gene expression and behaviour collectively and synchronously, and assess their own population. As a promising method of molecular communication, bacterial populations can be programmed as bio-transceivers to establish information transmission using molecules. In this work, to investigate the key features for molecular communication, a bacterial QS system is introduced, which contains two clusters of bacteria, specifically Vibrio fischeri , as the transmitter node and receiver node, and the diffusive channel. The transmitted information is represented by the concentration of autoinducers with on–off keying (OOK) modulation. In addition, to achieve better reliability, transmission efficiency and channel throughput performance, different Automatic Repeat reQuest (ARQ) protocols are taken into consideration. This configuration is investigated via simulation and the consequent results discussed. The performance of the system is evaluated in terms of transmission time, efficiency, bit error rate (BER) and channel throughput. Results show that Selective-Repeat (SR-ARQ) performs better than Go-Back-N (GBN-ARQ), while the performance of Stop-N-Wait (SW-ARQ) varies for different channel conditions, which is quite different from the performance of ARQ schemes in traditional networking areas. [ABSTRACT FROM AUTHOR]