Decoding spatial locations from primate lateral prefrontal cortex neural activity during virtual navigation.

Objective. Decoding the intended trajectories from brain signals using a brain-computer interface system could be used to improve the mobility of patients with disabilities.Approach. Neuronal activity associated with spatial locations was examined while macaques performed a navigation task within a virtual environment.Main results.Here, we provide proof of principle that multi-unit spiking activity recorded from the lateral prefrontal cortex (LPFC) of non-human primates can be used to predict the location of a subject in a virtual maze during a navigation task. The spatial positions within the maze that require a choice or are associated with relevant task events can be better predicted than the locations where no relevant events occur. Importantly, within a task epoch of a single trial, multiple locations along the maze can be independently identified using a support vector machine model.Significance. Considering that the LPFC of macaques and humans share similar properties, our results suggest that this area could be a valuable implant location for an intracortical brain-computer interface system used for spatial navigation in patients with disabilities.

High-resolution global maps of tidal flat ecosystems from 1984 to 2019.

Assessments of the status of tidal flats, one of the most extensive coastal ecosystems, have been hampered by a lack of data on their global distribution and change. Here we present globally consistent, spatially-explicit data of the occurrence of tidal flats, defined as sand, rock or mud flats that undergo regular tidal inundation. More than 1.3 million Landsat images were processed to 54 composite metrics for twelve 3-year periods, spanning four decades (1984-1986 to 2017-2019). The composite metrics were used as predictor variables in a machine-learning classification trained with more than 10,000 globally distributed training samples. We assessed accuracy of the classification with 1,348 stratified random samples across the mapped area, which indicated overall map accuracies of 82.2% (80.0-84.3%, 95% confidence interval) and 86.1% (84.2-86.8%, 95% CI) for version 1.1 and 1.2 of the data, respectively. We expect these maps will provide a means to measure and monitor a range of processes that are affecting coastal ecosystems, including the impacts of human population growth and sea level rise.

SMS reminders to improve the uptake and timeliness of the primary immunisation series in infants: a multi-centre randomised controlled trial.

Background: Immunisation timeliness continues to present challenges to achieving optimal vaccine coverage in infancy, particularly in disadvantaged groups and Australian First Nations infants. We aimed to determine whether a tailored, educational SMS reminder improves the timeliness of immunisation in infants up to seven months of age. Methods: A pragmatic, three-arm, parallel-group, randomised controlled trial of immunisation reminders was conducted in two First-Nations-specific primary health care centres and two public hospital antenatal clinics in South East Queensland, Australia. Live-born infants of mothers enrolled during pregnancy were randomised at birth and followed to eight months of age. One group received a simple SMS reminder at two weeks before, the week of, and two weeks after the due date for immunisation at two, four and six months of age. The second group received a tailored SMS with an educational message at two weeks before and on the date immunisations were due; those not immunised two weeks following the due date were offered support to immunise the baby. Controls received no intervention or contact until the baby turned seven months of age. The primary outcome was the proportion of infants age-appropriately vaccinated at seven months of age as recorded on the Australian Immunisation Register. Secondary outcomes included vaccination status at three and five months of age. Results: Between 30 May 2016 and 24 May 2018, one hundred and ninety-six infants (31% First Nations infants) were randomised. At seven months of age, 54/65 (83.1%) infants in the educational SMS ± additional support group (ESMS±S) were age-appropriately immunised, compared to 45/64 (70.3%) in the simple SMS group and 45/67 (67.2%) in controls. Differences were most marked at five months of age: ESMS±S 95.5%; simple SMS 73.4%; controls 75.8%. The difference between the ESMS±S group and the other two groups at seven months of age was no longer apparent when those who received additional support beyond the SMS were assumed to have not been vaccinated if that support had not been received. Discussion: A tailored SMS reminder system using an educational message and with provision of additional support to mothers is more effective in improving immunisation timeliness in infants at three and five months of age than a simple message and no intervention. The additional support was required at seven months of age in order to achieve higher coverage in the ESMS±S group.

Decoding Saccade Intention From Primate Prefrontal Cortical Local Field Potentials Using Spectral, Spatial, and Temporal Dimensionality Reduction.

Most invasive Brain Computer Interfaces (iBCIs) use spike and Local Field Potentials (LFPs) from the motor or parietal cortices to decode movement intentions. It has been debated whether harvesting signals from other brain areas that encode global cognitive variables, such as the allocation of attention and eye movement goals in a variety of spatial reference frames, may improve the outcome of iBCIs. Here, we explore the ability of LFP signals, sampled from the lateral prefrontal cortex (LPFC) of macaque monkeys, to encode eye-movement intention during the pre-movement fixation period of a delayed saccade task. We use spectral dimensionality reduction to examine the spatiotemporal properties of the extracted non-rhythmic broadband activity and explore its usefulness in decoding saccade goals. The dynamics of the broadband signal in low spatial dimensions across the pre-movement fixation period uncovered saccade target separation; its discriminative potential was confirmed using support vector machine classifications. These findings reveal that broadband LFP from the LPFC can be used to decode intended saccade target location during pre-movement periods. We further provide a general workflow that can be implemented in iBCIs and it is relatively robust to the loss of spikes in individual electrodes.

A Test of How Australian Adults Allocate Time for Physical Activity.

The most common reported barrier to physical activity is a lack of sufficient time. Just like most resources in economics are finite, so too is time within a day. We utilized a time-utility model to better understand how people are allocating time for physical activity. Additionally, we tested whether the allocation of physical activity time impacts people's perception of "lack of time" as a barrier for physical activity or their likelihood of being sufficiently physical active. Australian adults (N = 725 participants, 54% men) reported their time use throughout their day, perceived lack of time as a barrier to activity, and physical activity. Cluster analysis and χ2-tests were used to test the study research questions. People tended to either be entirely inactive (29%) or active while doing either leisure (18%), occupation (18%), transport (14%), or household (22%) activities. Those who were active during their leisure or transport time were most likely to be sufficiently active. There were no significant differences among clusters in how much people perceived that lack of time was a physical activity barrier. The commonly reported barrier of not having enough time to be active might be a fallacy. Although a lack of time is a commonly reported barrier of physical activity, these findings bring to light that increasing physical activity behavior is not as simple as adding more time to the day.

The global distribution and trajectory of tidal flats.

Increasing human populations around the global coastline have caused extensive loss, degradation and fragmentation of coastal ecosystems, threatening the delivery of important ecosystem services1. As a result, alarming losses of mangrove, coral reef, seagrass, kelp forest and coastal marsh ecosystems have occurred1-6. However, owing to the difficulty of mapping intertidal areas globally, the distribution and status of tidal flats-one of the most extensive coastal ecosystems-remain unknown7. Here we present an analysis of over 700,000 satellite images that maps the global extent of and change in tidal flats over the course of 33 years (1984-2016). We find that tidal flats, defined as sand, rock or mud flats that undergo regular tidal inundation7, occupy at least 127,921 km2 (124,286-131,821 km2, 95% confidence interval). About 70% of the global extent of tidal flats is found in three continents (Asia (44% of total), North America (15.5% of total) and South America (11% of total)), with 49.2% being concentrated in just eight countries (Indonesia, China, Australia, the United States, Canada, India, Brazil and Myanmar). For regions with sufficient data to develop a consistent multi-decadal time series-which included East Asia, the Middle East and North America-we estimate that 16.02% (15.62-16.47%, 95% confidence interval) of tidal flats were lost between 1984 and 2016. Extensive degradation from coastal development1, reduced sediment delivery from major rivers8,9, sinking of riverine deltas8,10, increased coastal erosion and sea-level rise11 signal a continuing negative trajectory for tidal flat ecosystems around the world. Our high-spatial-resolution dataset delivers global maps of tidal flats, which substantially advances our understanding of the distribution, trajectory and status of these poorly known coastal ecosystems.

Practical solutions for injury surveillance at mass gatherings.

INTRODUCTION: Public safety at mass gatherings is the responsibility of multiple agencies. Injury surveillance and inter-agency communication are pivotal to ensure continued public safety. OBJECTIVES: The principal objective of this pilot study was to improve the identification of trends and patterns of injury presentations at mass gatherings. This was achieved through an electronic process for data gathering to support timely reporting of injury data. In addition, what evolved was the development of an inter-agency communication model to support information transfer. METHODS: An Electronic Injury Surveillance System was created and piloted at two mass gatherings in South Australia. Live, real-time data were collected via customized software supported by electronic report generation. RESULTS: The Injury Surveillance System captured data on 181 injured patients and assisted in the identification of trends and patterns of presentations. The relevant injuries and patterns of injuries were reported to the appropriate organizations based on pre-defined communication models. CONCLUSIONS: The pilot study demonstrated that it was possible to perform "live", portable injury surveillance during patient presentations at two mass gatherings. The Injury Surveillance System ensured immediate data capture. Well-defined communication systems established for this pilot also enabled early action to rectify hazards. Further development of electronic injury surveillance should be considered as an essential tool for managing public safety at mass gatherings.