Paraunitary oversampled filter bank design for channel coding

Oversampled filter banks (OSFBs) have been considered for channel coding, since their redundancy can be utilised to permit the detection and correction of channel errors. In this paper, we propose an OSFB-based channel coder for a correlated additive Gaussian noise channel, of which the noise covariance matrix is assumed to be known. Based on a suitable factorisation of this matrix, we develop a design for the decoder's synthesis filter bank in order to minimise the noise power in the decoded signal, subject to admitting perfect reconstruction through paraunitarity of the filter bank. We demonstrate that this approach can lead to a significant reduction of the noise interference by exploiting both the correlation of the channel and the redundancy of the filter banks. Simulation results providing some insight into these mechanisms are provided

Optimal Network QoS over the Internet of Vehicles for E-Health Applications

Wireless technologies are pervasive to support ubiquitous healthcare applications. However, a critical issue of using wireless communications under a healthcare scenario is the electromagnetic interference (EMI) caused by RF transmission, and a high level of EMI may lead to a critical malfunction of medical sensors. In consideration of EMI on medical sensors, we study the optimization of quality of service (QoS) within the whole Internet of vehicles for E-health and propose a novel model to optimize the QoS by allocating the transmit power of each user. Our results show that the optimal power control policy depends on the objective of optimization problems: a greedy policy is optimal to maximize the summation of QoS of each user, whereas a fair policy is optimal to maximize the product of QoS of each user. Algorithms are taken to derive the optimal policies, and numerical results of optimizing QoS are presented for both objectives and QoS constraints

Nanowire FET based neural element for robotic tactile sensing skin

This paper presents novel Neural Nanowire Field Effect Transistors (υ-NWFETs) based hardware-implementable neural network (HNN) approach for tactile data processing in electronic skin (e-skin). The viability of Si nanowires (NWs) as the active material for υ-NWFETs in HNN is explored through modeling and demonstrated by fabricating the first device. Using υ-NWFETs to realize HNNs is an interesting approach as by printing NWs on large area flexible substrates it will be possible to develop a bendable tactile skin with distributed neural elements (for local data processing, as in biological skin) in the backplane. The modeling and simulation of υ-NWFET based devices show that the overlapping areas between individual gates and the floating gate determines the initial synaptic weights of the neural network - thus validating the working of υ-NWFETs as the building block for HNN. The simulation has been further extended to υ-NWFET based circuits and neuronal computation system and this has been validated by interfacing it with a transparent tactile skin prototype (comprising of 6 × 6 ITO based capacitive tactile sensors array) integrated on the palm of a 3D printed robotic hand. In this regard, a tactile data coding system is presented to detect touch gesture and the direction of touch. Following these simulation studies, a four-gated υ-NWFET is fabricated with Pt/Ti metal stack for gates, source and drain, Ni floating gate, and Al2O3 high-k dielectric layer. The current-voltage characteristics of fabricated υ-NWFET devices confirm the dependence of turn-off voltages on the (synaptic) weight of each gate. The presented υ-NWFET approach is promising for a neuro-robotic tactile sensory system with distributed computing as well as numerous futuristic applications such as prosthetics, and electroceuticals

Prevalence of skin pressure injury in critical care patients in the UK: results of a single-day point prevalence evaluation in adult critically ill patients.

OBJECTIVES: Hospital-acquired pressure injuries (PIs) are a source of morbidity and mortality, and many are potentially preventable. DESIGN: This study prospectively evaluated the prevalence and the associated factors of PIs in adult critical care patients admitted to intensive care units (ICU) in the UK. SETTING: This service evaluation was part of a larger, international, single-day point prevalence study of PIs in adult ICU patients. Training was provided to healthcare givers using an electronic platform to ensure standardised recognition and staging of PIs across all sites. PARTICIPANTS: The characteristics of the ICUs were recorded before the survey; deidentified patient data were collected using a case report form and uploaded onto a secure online platform. PRIMARY AND SECONDARY OUTCOME MEASURES: Factors associated with ICU-acquired PIs in the UK were analysed descriptively and using mixed multiple logistic regression analysis. RESULTS: Data from 1312 adult patients admitted to 94 UK ICUs were collected. The proportion of individuals with at least one PI was 16% (211 out of 1312 patients), of whom 8.8% (n=115/1312) acquired one or more PIs in the ICU and 7.3% (n=96/1312) prior to ICU admission. The total number of PIs was 311, of which 148 (47.6%) were acquired in the ICU. The location of majority of these PIs was the sacral area, followed by the heels. Braden score and prior length of ICU stay were associated with PI development. CONCLUSIONS: The prevalence and the stage of severity of PIs were generally low in adult critically ill patients admitted to participating UK ICUs during the study period. However, PIs are a problem in an important minority of patients. Lower Braden score and longer length of ICU stay were associated with the development of injuries; most ICUs assess risk using tools which do not account for this. TRIAL REGISTRATION NUMBER: NCT03270345

An Investigation of Nurses' Knowledge, Attitudes, and Practices Regarding Disinfection Procedures in Italy

<p>Abstract</p> <p>Background</p> <p>This study assessed the level of knowledge, attitudes, and practice regarding disinfection procedures among nurses in Italian hospitals.</p> <p>Methods</p> <p>A face-to-face interview gathered the following information: demographic and practice characteristics; knowledge about the healthcare-associated infections (HAIs) and the disinfection practices; attitudes towards the utility of guidelines/protocols and perception of the risks of acquiring/transmitting HAIs; compliance with antisepsis/disinfection procedures; and sources of information.</p> <p>Results</p> <p>Only 29% acknowledged that urinary and respiratory tract infections were the two most common HAIs and this knowledge was significantly higher in those with a higher level of education. Attitudes towards the utility of guidelines/protocols for disinfection procedures showed a mean score of 9.1. The results of the linear regression model indicated a more positive attitude in female nurses, in those with a lower number of years of activity, and in those needing additional information about disinfection procedures. Nurses with higher educational level and with a higher perception of risk of transmitting an infectious disease while working were more likely to perform appropriate antisepsis of the surgical wound and handwashing before and after medication.</p> <p>Conclusions</p> <p>Plan of successful prevention activities about HAIs and provide pointers to help optimize disinfection procedures and infection prophylaxis and management are needed.</p

Nano-engineered electron–hole exchange interaction controls exciton dynamics in core–shell semiconductor nanocrystals

A strong electron–hole exchange interaction (EI) in semiconductor nanocrystals (NCs) gives rise to a large (up to tens of meV) splitting between optically active ('bright') and optically passive ('dark') excitons. This dark–bright splitting has a significant effect on the optical properties of band-edge excitons and leads to a pronounced temperature and magnetic field dependence of radiative decay. Here we demonstrate a nanoengineering-based approach that provides control over EI while maintaining nearly constant emission energy. We show that the dark–bright splitting can be widely tuned by controlling the electron–hole spatial overlap in core–shell CdSe/CdS NCs with a variable shell width. In thick-shell samples, the EI energy reduces to <250 μeV, which yields a material that emits with a nearly constant rate over temperatures from 1.5 to 300 K and magnetic fields up to 7 T. The EI-manipulation strategies demonstrated here are general and can be applied to other nanostructures with variable electron–hole overlap

Probing and controlling fluorescence blinking of single semiconductor nanoparticles

In this review we present an overview of the experimental and theoretical development on fluorescence intermittency (blinking) and the roles of electron transfer in semiconductor crystalline nanoparticles. Blinking is a very interesting phenomenon commonly observed in single molecule/particle experiments. Under continuous laser illumination, the fluorescence time trace of these single nanoparticles exhibit random light and dark periods. Since its first observation in the mid-1990s, this intriguing phenomenon has attracted wide attention among researchers from many disciplines. We will first present the historical background of the discovery and the observation of unusual inverse power-law dependence for the waiting time distributions of light and dark periods. Then, we will describe our theoretical modeling efforts to elucidate the causes for the power-law behavior, to probe the roles of electron transfer in blinking, and eventually to control blinking and to achieve complete suppression of the blinking, which is an annoying feature in many applications of quantum dots as light sources and fluorescence labels for biomedical imaging