Hippocampal state transitions at the boundaries between trial epochs

The hippocampus encodes distinct contexts with unique patterns of activity. Representational shifts with changes in context, referred to as remapping, have been extensively studied. However, less is known about transitions between representations. In this study, we leverage a large dataset of neuronal recordings taken while rats performed an olfactory memory task with a predictable temporal structure involving trials and intertrial intervals (ITIs), separated by salient boundaries at the trial start and trial end. We found that trial epochs were associated with stable hippocampal representations despite moment‐to‐moment variability in stimuli and behavior. Representations of trial and ITI epochs were far more distinct than spatial factors would predict and the transitions between the two were abrupt. The boundary was associated with a large spike in multiunit activity, with many individual cells specifically active at the start or end of each trial. Both epochs and boundaries were encoded by hippocampal populations, and these representations carried information on orthogonal axes readily identified using principal component analysis. We suggest that the hippocampus orthogonalizes representations of the trial and ITI epochs and the activity spike at trial boundaries might serve to drive hippocampal activity from one stable state to the other.     

Developing a national undergraduate standardized curriculum for future healthcare professionals on “Making Every Contact Count” for chronic disease prevention in the Republic of Ireland

ABSTRACT

This report describes the development of the first national undergraduate interprofessional standardized curriculum in chronic disease prevention for healthcare professionals in the Republic of Ireland. This project brought together for the first time all higher education institutions nationwide in a novel collaboration with the national health service i.e. the Health Service Executive (HSE), to develop a standardized national curriculum for undergraduate health care professions. The curriculum sits within the framework of Making Every Contact Count, the goal of which is to re-orientate health services to embed the ethos of prevention through lifestyle behavior change as part of the routine care of health professionals. The core focus of Making Every Contact Count is chronic disease prevention, targeting four main lifestyle risk factors for chronic disease; tobacco use, alcohol consumption, physical inactivity and unhealthy eating. Making Every Contact Count is a key component of Healthy Ireland, the Irish national framework for health and wellbeing. The aim of the curriculum is to prepare newly qualified health professionals with the skills needed to support patients to achieve lifestyle behavior change delivered as part of routine clinical care.     

Non-linear Wave Propagation and Safety Standards for Diagnostic Ultrasound Devices

Safety standards for clinical diagnostic ultrasonic devices were developed for use in relatively low-frequency systems (1–10 MHz), under the assumption that non-linear effects would be negligible. This article reviews ways in which neglecting non-linear wave propagation affects the measurements and calculations required to comply with safety standards and U.S. Food and Drug Administration guidance that recognizes these standards. An attempt is made to evaluate whether ignoring non-linear effects could result in significant error in the exposure quantities defined in these standards at either low or high frequencies, based on published literature. This article maintains that although non-linear effects have been considered in some parts of safety standards related to hydrophone requirements, the coverage is inadequate, especially for modern equipment with high working frequencies. A new approach is required to assess the magnitude of thermal heating for recently developed high-frequency systems to incorporate non-linear effects. In contrast, the current approach for evaluating the risk of cavitation can be used after appropriate modifications.     

Spectral Shift Originating from Non-linear Ultrasonic Wave Propagation and Its Effect on Imaging Resolution

An amplitude-dependent downshift in the fundamental wave spectrum of a propagating ultrasonic pulse caused by non-linear wave propagation is described. The effects of non-linearity and the associated downshift on spatial resolution are also studied. The amounts of downshift and spatial resolution are extracted from the numerically simulated beam profile based on the KZK equation. Results for a 25-MHz transducer reveal that non-linear effects can lead to 58% additional downshift in the centre frequency of a pulse compared with a linear case with downshift caused only by attenuation. This additional downshift causes about 50% degradation in axial resolution. However, as the beam becomes narrower from the non-linear effects, the overall effect of non-linearity still leads to improved lateral resolution (≤26%). Therefore, as non-linearity increases with wave pressure, it is concluded that the increase in source pressure improves lateral resolution and degrades axial resolution.     

The effects of education levels of developmental care in Australia: Perceptions and challenges

BackgroundDevelopmental care consists of a range of clinical, infant-focused, and family-focused interventions designed to modify the neonatal intensive care environment and caregiving practices to reduce stressors on the developing brain. Since the inception of developmental care in the early 1980s, it has been recommended and adopted globally as a component of routine practice for neonatal care. Despite its application for almost 40 y, little is known of the attitude of neonatal nurses in Australia towards the intervention.Aims and objectivesThe objective of this study was to establish Australian neonatal nurse perceptions of developmental care and explore associations between developmental care education levels of the nurses and personal beliefs in the application of developmental care.DesignThis involves a cross-sectional survey design.MethodsAn online questionnaire was completed by 171 neonatal nurses. Participants were members of the Australian College of Neonatal Nursing (n = 783). Covariate associations between key components of developmental care and respondents' geographical location, place of employment, professional qualifications, and developmental care education level were analysed. The reporting of this study is in accordance with the Enhancing the Quality and Transparency of Health Research Checklist for Reporting Results of Internet E-Surveys.ResultsDifferences were observed between groups for geographical location, place of employment, and professional qualification level. Rural nurses were less likely to support the provision of skin-to-skin care (odds ratio [OR]: 0.6, 95% confidence interval [CI]: 0.2–1.8) than nurses in a metropolitsan unit. Nurses working in a neonatal intensive care unit and nurses with postgraduate qualifications were more likely to support parental involvement in care ([OR: 2.3, 95% CI: 0.9–6.2] and [OR: 2.1, 95% CI: 0.6–7.4], respectively). Rural respondents were more likely to have attended off-site education (OR: 3.6, 95% CI: 1.3–9.9) than metropolitan respondents.ConclusionThe application of developmental care in Australia may be influenced by inadequate resources and inequitable access to educational resources, and similar challenges have been reported in other countries. Overcoming the challenges requires a focused education strategy and support within and beyond the neonatal intensive care unit.