Sexual dimorphism in relation to adipose tissue and intrahepatocellular lipid deposition in early infancy

Sexual dimorphism in adiposity is well described in adults, but the age at which differences first manifest is uncertain. Using a prospective cohort, we describe longitudinal changes in directly measured adiposity and intrahepatocellular lipid (IHCL) in relation to sex in healthy term infants. At median ages of 13 and 63 days, infants underwent quantification of adipose tissue depots by whole-body magnetic resonance imaging and measurement of IHCL by in vivo proton magnetic resonance spectroscopy. Longitudinal data were obtained from 70 infants (40 boys and 30 girls). In the neonatal period girls are more adipose in relation to body size than boys. At follow-up (median age 63 days), girls remained significantly more adipose. The greater relative adiposity that characterises girls is explained by more subcutaneous adipose tissue and this becomes increasingly apparent by follow-up. No significant sex differences were seen in IHCL. Sex-specific differences in infant adipose tissue distribution are in keeping with those described in later life, and suggest that sexual dimorphism in adiposity is established in early infancy.

Sensory imagery in individuals who are blind and sighted: examining unimodal and multimodal forms

Introduction: Previous research has suggested that visual images are more easily generated, more vivid and more memorable than other sensory modalities. This research examined whether or not imagery is experienced in similar ways by people with and without sight. Specifically, the imabeability of visual, auditory and tactile cue words was compared. The degree to which images were multimodal or unimodal was also examined. Method: Twelve participants totally blind from early infancy and 12 sighted participants generated images in response to 53 sensory and non sensory words, rating imageability and the sensory modality, and describing images. From these 53 items, 4 subgroups of words, which stimulated images that were predominantly visual, tactile, auditory and low-imagery, respectively, were created. Results: T-tests comparing imageability ratings from blind and sighted participants found no differences for auditory and tactile words (both p>.1). Nevertheless, whilst participants without sight found auditory and tactile images equally imageable, sighted participants found images in response to tactile cue words harder to generate than visual cue words (mean difference: -0.51, p=.025). Participants with sight were also more likely to develop multisensory images than were participants without sight (both U≥15.0, N1=12, N2=12, p≤.008). Discussion: For both the blind and sighted, auditory and tactile images were rich and varied and similar language was used. Sighted participants were more likely to generate multimodal images. This was particularly the case for tactile words. Nevertheless, cue words that resulted in multisensory images were not necessarily rated as more imageable. The discussion considers whether or not multimodal imagery represent a method of compensating for impoverished unimodal imagery. Implications for Practitioners: Imagery is important not only as a mnemonic in memory rehabilitation, but also everyday uses for things such as autobiographical memory. This research emphasises both the importance of not only auditory and tactile sensory imagery, but also spatial imagery for people without sight.

Applying gaze-contingent training within community settings to infants from diverse SES backgrounds

Even in infancy children from low-SES backgrounds differ in frontal cortex functioning and, by the start of preschool, they frequently show poor performance on executive functions including attention control. These differences may causally mediate later difficulties in academic learning. Here, we present a study to assess the feasibility of using computerized paradigms to train attention control in infants, delivered weekly over five sessions in early intervention centres for low-SES families. Thirty-three 12-month-old infants were recruited, of whom 23 completed the training. Our results showed the feasibility of repeat-visit cognitive training within community settings. Training-related improvements were found, relative to active controls, on tasks assessing visual sustained attention, saccadic reaction time, and rule learning, whereas trend improvements were found on assessments of short-term memory. No significant improvements were found in task switching. These results warrant further investigation into the potential of this method for targeting ‘at-risk’ infants in community settings.

Allocentric spatial performance higher in early-blind and sighted adults than in retinopathy-of-prematurity adults

The question as to whether people totally blind since infancy process allocentric or ‘external’ spatial information like the sighted has caused considerable debate within the literature. Due to the extreme rarity of the population, researchers have often included individuals with Retinopathy of Prematurity (RoP – over oxygenation at birth) within the sample. However, RoP is inextricably confounded with prematurity per se. Prematurity, without visual disability, has been associated with spatial processing difficulties. In this experiment, blindfolded sighted and two groups of functionally totally blind participants heard text descriptions from a survey (allocentric) or route (egocentric) perspective. One blind group lost their sight due to retinopathy of prematurity (RoP – over oxygenation at birth) and a second group before 24 months of age. The accuracy of participants’ mental representations derived from the text descriptions were assessed via questions and maps. The RoP participants had lower scores than the sighted and early blind, who performed similarly. In other words, it was not visual impairment alone that resulted in impaired allocentric spatial performance in this task, but visual impairment together with RoP. This finding may help explain the contradictions within the existing literature on the role of vision in allocentric spatial processing.

Acceleration and visualization of Dynamic Network Optimization

With the emerging prevalence of smart phones and 4G LTE networks, the demand for faster-better-cheaper mobile services anytime and anywhere is ever growing. The Dynamic Network Optimization (DNO) concept emerged as a solution that optimally and continuously tunes the network settings, in response to varying network conditions and subscriber needs. Yet, the DNO realization is still at infancy, largely hindered by the bottleneck of the lengthy optimization runtime. This paper presents the design and prototype of a novel cloud based parallel solution that further enhances the scalability of our prior work on various parallel solutions that accelerate network optimization algorithms. The solution aims to satisfy the high performance required by DNO, preliminarily on a sub-hourly basis. The paper subsequently visualizes a design and a full cycle of a DNO system. A set of potential solutions to large network and real-time DNO are also proposed. Overall, this work creates a breakthrough towards the realization of DNO.

Distributed parallelization of greedy Mobile Network Optimization algorithms

The Mobile Network Optimization (MNO) technologies have advanced at a tremendous pace in recent years. And the Dynamic Network Optimization (DNO) concept emerged years ago, aimed to continuously optimize the network in response to variations in network traffic and conditions. Yet, DNO development is still at its infancy, mainly hindered by a significant bottleneck of the lengthy optimization runtime. This paper identifies parallelism in greedy MNO algorithms and presents an advanced distributed parallel solution. The solution is designed, implemented and applied to real-life projects whose results yield a significant, highly scalable and nearly linear speedup up to 6.9 and 14.5 on distributed 8-core and 16-core systems respectively. Meanwhile, optimization outputs exhibit self-consistency and high precision compared to their sequential counterpart. This is a milestone in realizing the DNO. Further, the techniques may be applied to similar greedy optimization algorithm based applications.