Optimisation of a droplet digital PCR assay for the diagnosis of Schistosoma japonicum infection: A duplex approach with DNA binding dye chemistry

Schistosomiasis is a chronically debilitating helminth infection with a significant socio-economic and public health impact. Accurate diagnostics play a pivotal role in achieving current schistosomiasis control and elimination goals. However, many of the current diagnostic procedures, which rely on detection of schistosome eggs, have major limitations including lack of accuracy and the inability to detect pre-patent infections. DNA-based detection methods provide a viable alternative to the current tests commonly used for schistosomiasis diagnosis. Here we describe the optimisation of a novel droplet digital PCR (ddPCR) duplex assay for the diagnosis of Schistosoma japonicum infection which provides improved detection sensitivity and specificity. The assay involves the amplification of two specific and abundant target gene sequences in S. japonicum; a retrotransposon (SjR2) and a portion of a mitochondrial gene (nad1). The assay detected target sequences in different sources of schistosome DNA isolated from adult worms, schistosomules and eggs, and exhibits a high level of specificity, thereby representing an ideal tool for the detection of low levels of parasite DNA in different clinical samples including parasite cell free DNA in the host circulation and other bodily fluids. Moreover, being quantitative, the assay can be used to determine parasite infection intensity and, could provide an important tool for the detection of low intensity infections in low prevalence schistosomiasis-endemic areas.

Energy efficiency optimization in hardware-constrained large-scale MIMO systems

Large-scale multiple-input multiple-output (MIMO) communication systems can bring substantial improvement in spectral efficiency and/or energy efficiency, due to the excessive degrees-of-freedom and huge array gain. However, large-scale MIMO is expected to deploy lower-cost radio frequency (RF) components, which are particularly prone to hardware impairments. Unfortunately, compensation schemes are not able to remove the impact of hardware impairments completely, such that a certain amount of residual impairments always exists. In this paper, we investigate the impact of residual transmit RF impairments (RTRI) on the spectral and energy efficiency of training-based point-to-point large-scale MIMO systems, and seek to determine the optimal training length and number of antennas which maximize the energy efficiency. We derive deterministic equivalents of the signal-to-noise-and-interference ratio (SINR) with zero-forcing (ZF) receivers, as well as the corresponding spectral and energy efficiency, which are shown to be accurate even for small number of antennas. Through an iterative sequential optimization, we find that the optimal training length of systems with RTRI can be smaller compared to ideal hardware systems in the moderate SNR regime, while larger in the high SNR regime. Moreover, it is observed that RTRI can significantly decrease the optimal number of transmit and receive antennas.

No second chance: junior neonatal nurses' experiences of caring for babies at the end-of-life and their families

Death of an infant is acutely stressful for parents and professionals. Little is known about junior nurses' experiences providing end-of-life care in Neonatal units (NNU). This study aimed to better understand junior nurses' experiences providing end-of-life care in NNU. Neonatal nurses (n = 12) with less than 3 years experience participated in a focus group. Nominal Group Technique (NGT) was used to build consensus around the challenges faced, alongside suggested developments in improving future care provision. Primary analysis involved successive rounds of ranking and decision-making whilst secondary analysis involved thematic analysis. All issues, whether environmental, professional or social appeared driven by an awareness on the part of nurses, that there was no ‘second chance’ which created a huge pressure to ‘get if right’ for the infants and families. Regarding future care 2 areas of improvement identified were ‘Education and Training’ and Support. This paper unpacks these findings making recommendations for practice.

Physical model parameter optimisation for calibrated emulation of the Dallas Rangemaster Treble Booster guitar pedal

In this work we explore optimising parameters of a physical circuit model relative to input/output measurements, using the Dallas Rangemaster Treble Booster as a case study. A hybrid metaheuristic/gradient descent algorithm is implemented, where the initial parameter sets for the optimisation are informed by nominal values from schematics and datasheets. Sensitivity analysis is used to screen parameters, which informs a study of the optimisation algorithm against model complexity by fixing parameters. The results of the optimisation show a significant increase in the accuracy of model behaviour, but also highlight several key issues regarding the recovery of parameters.

No second chance: the experiences of junior neonatal nurses in providing end-of-life care for babies and families in the NNU

Background

An infant’s death is acutely stressful for parents and professionals. Little is known about junior nurses’ experiences providing end-of-life care in Neonatal Units (NNU).

Objectives

To better understand junior nurses’ experiences providing end-of-life care in NNU, the study explored the challenges and opportunities inherent in their practice relating to providing such care to babies and their families.

Methods

Neonatal nurses (n=12) with less than 3 years’ experience who were undergoing a neonatal education programme participated. Two focus groups were convened each with 6 nurses. The Ethics Committee at the relevant University approved the study. Nominal Group Technique (NGT) was used in the focus groups to build consensus around the challenges faced by junior nurses, alongside suggested developments in improving future care provision. Primary analysis involved successive rounds of ranking and decision making whilst secondary analysis involved thematic analysis.

Results

The study identified the pressures these nurses felt in having only one chance to ‘get it right’ for the infants and their families. They perceived the need for further ‘education and training’ highlighting that improved education provision would include both additional courses and internal training sessions. Greater ‘support’ from mentors themselves more experienced in this aspect of care within the NNU was identified as important in addressing issues around confidence building and skill development.

Conclusions

The results highlight junior nurses’ need for specific education and mentorship around end-of-life care for babies. This presentation will outline the implications for practice, education and further research.