Interference suppression in HO fluorescence detection

In this Letter we report preliminary results on a sampling method that greatly reduces the above interferences relative to hydroxyl fluorescence

Physical activity and sedentary time among preschoolers in centre-based childcare: A systematic review 11 Medical and Health Sciences 1117 Public Health and Health Services

Background: Many preschoolers spend a substantial portion of their day enrolled in centre-based childcare; the amounts of physical activity and sedentary time accumulated in this environment are critical to preschoolers\u27 ability to meet movement guidelines. The purpose of this systematic review was to provide a comprehensive overview of the objectively assessed physical activity and sedentary time of preschoolers in centre-based childcare (registration no. CRD42016033502). Methods: Eight online databases were searched using terms related to physical activity, sedentary time, preschoolers and centre-based childcare. Published, peer-reviewed primary studies written in English that objectively assessed (via accelerometry) the physical activity and sedentary time of preschoolers (2-5 years) in centre-based childcare were included. Results: Fifty-five studies (published 2004-2017) from 11 countries, representing 13,956 participants were included. Studies reported light physical activity (n=38) ranging from 2.94 to 29.96 mins/hr, moderate-to-vigorous physical activity (n=46) which ranged from 1.29 to 22.66 mins/hr, and total physical activity (n=42) ranging from 4.23 to 47.17 mins/hr. Sedentary time (n=47) ranged from 12.38 to 55.77 mins/hr. Conclusion: Physical activity and sedentary time were highly varied and inconsistent between studies; therefore, it is difficult to determine preschoolers\u27 true amount of physical activity and sedentary time during childcare hours. Despite this variability, preschoolers were noted to participate in high rates of sedentary time in this setting. The lack of homogeneity is an important finding in and of itself as it highlights the lack of consistency in measuring, processing, and reporting paediatric physical activity data

Development and characterisation of a collagen nano-hydroxyapatite composite scaffold for bone tissue engineering.

Bone regeneration requires scaffolds that possess suitable mechanical and biological properties. This study sought to develop a novel collagen-nHA biocomposite scaffold via two new methods. Firstly a stable nHA suspension was produced and added to a collagen slurry (suspension method), and secondly, porous collagen scaffolds were immersed in nHA suspension after freeze-drying (immersion method). Significantly stronger constructs were produced using both methods compared to collagen only scaffolds, with a high porosity maintained (\u3e98.9%). It was found that Coll-nHA composite scaffolds produced by the suspension method were up to 18 times stiffer than the collagen control (5.50 +/- 1.70 kPa vs. 0.30 +/- 0.09 kPa). The suspension method was also more reproducible, and the quantity of nHA incorporated could be varied with greater ease than with the immersion technique. In addition, Coll-nHA composites display excellent biological activity, demonstrating their potential as bone graft substitutes in orthopaedic regenerative medicine

The Effects of Distraction and a Brief Intervention on Auditory and Visual-Spatial Working Memory in College Students with Attention Deficit Hyperactivity Disorder

Two studies addressed how young adult college students with attention deficit hyperactivity disorder (ADHD) (n = 44) compare to their nonaffected peers (n = 42) on tests of auditory and visual–spatial working memory (WM), are vulnerable to auditory and visual distractions, and are affected by a simple intervention. Students with ADHD demonstrated worse auditory WM than did controls. A near significant trend indicated that auditory distractions interfered with the visual WM of both groups and that, whereas controls were also vulnerable to visual distractions, visual distractions improved visualWM in the ADHD group. The intervention was ineffective. Limited correlations emerged between self-reported ADHD symptoms and objective test performances; students with ADHD who perceived themselves as more symptomatic often had better WM and were less vulnerable to distractions than their ADHD peers

Coupling Freshly Isolated CD44(+) Infrapatellar Fat Pad-Derived Stromal Cells with a TGF-β3 Eluting Cartilage ECM-Derived Scaffold as a Single-Stage Strategy for Promoting Chondrogenesis.

An alternative strategy to the use of in vitro expanded cells in regenerative medicine is the use of freshly isolated stromal cells, where a bioactive scaffold is used to provide an environment conducive to proliferation and tissue-specific differentiation in vivo. The objective of this study is to develop a cartilage extracellular matrix (ECM)-derived scaffold that could facilitate the rapid proliferation and chondrogenic differentiation of freshly isolated stromal cells. By freeze-drying cryomilled cartilage ECM of differing concentrations, it is possible to produce scaffolds with a range of pore sizes. The migration, proliferation, and chondrogenic differentiation of infrapatellar fat pad-derived stem cells (FPSCs) depend on the concentration/porosity of these scaffolds, with greater sulphated glycosaminoglycan (sGAG) accumulation observed in scaffolds with larger-sized pores. It is then sought to determine if freshly isolated fat pad-derived stromal cells, seeded onto a transforming growth factor (TGF)-β3 eluting ECM-derived scaffold, could promote chondrogenesis in vivo. While a more cartilage-like tissue could be generated using culture expanded FPSCs compared to nonenriched freshly isolated cells, fresh CD44(+) stromal cells are capable of producing a tissue in vivo that stained strongly for sGAGs and type II collagen. These findings open up new possibilities for in-theatre cell-based therapies for joint regeneration

Subchondral osteopenia and accelerated bone remodelling post-ovariectomy - a possible mechanism for subchondral microfractures in the aetiology of spontaneous osteonecrosis of the knee?

Osteopenia and subchondral microfractures are implicated in the aetiology of spontaneous osteonecrosis of the knee. The ovine tibia shows significant alterations of the trabecular architecture within the subchondral bone of the medial tibial plateau post-ovariectomy, including reduced trabecular bone volume fraction. We hypothesise that accelerated subchondral bone resorption may also play a role in increasing microfracture risk at this site. 23 sheep were examined in this study; 10 of the sheep underwent ovariectomy (OVX), while the remainder (n=13) were kept as controls (CON). Five fluorochrome dyes were administered intravenously at 12 week intervals via the jugular vein to both groups, to label sites of bone turnover. These animals were then sacrificed at 12 months post-operatively. Bone turnover was significantly increased in the OVX group in both trabecular bone (2.024 vs. 1.047, p = 0.05) and within the subchondral bone plate (4.68 vs. 0.69 # / mm2; p \u3c 0.001). In addition to the classically-described turnover visible along trabecular surfaces, we also found visual evidence of intra-trabecular osteonal remodelling. In conclusion, this study shows significant alterations in bone turnover in both trabecular bone and within the subchondral bone plate at one-year post-ovariectomy. Remodelling of trabecular bone was due to both classically described hemi-osteonal and intra-trabecular osteonal remodelling. The presence of both localised osteopenia and accelerated bone remodelling within the medial tibial plateau provide a possible mechanism for subchondral microfractures in the aetiology of spontaneous osteonecrosis of the knee. Further utilisation of the ovariectomised ewe may be useful for further study in this field

SmileFinder: A Resampling-Based Approach to Evaluate Signatures of Selection from Genome-Wide Sets of Matching Allele Frequency Data in Two or More Diploid Populations

Background: Adaptive alleles may rise in frequency as a consequence of positive selection, creating a pattern of decreased variation in the neighboring loci, known as a selective sweep. When the region containing this pattern is compared to another population with no history of selection, a rise in variance of allele frequencies between populations is observed. One challenge presented by large genome-wide datasets is the ability to differentiate between patterns that are remnants of natural selection from those expected to arise at random and/or as a consequence of selectively neutral demographic forces acting in the population. Findings: SmileFinder is a simple program that looks for diversity and divergence patterns consistent with selection sweeps by evaluating allele frequencies in windows, including neighboring loci from two or more populations of a diploid species against the genome-wide neutral expectation. The program calculates the mean of heterozygosity and FST in a set of sliding windows of incrementally increasing sizes, and then builds a resampled distribution (the baseline) of random multi-locus sets matched to the sizes of sliding windows, using an unrestricted sampling. Percentiles of the values in the sliding windows are derived from the superimposed resampled distribution. The resampling can easily be scaled from 1 K to 100 M; the higher the number, the more precise the percentiles ascribed to the extreme observed values. Conclusions: The output from SmileFinder can be used to plot percentile values to look for population diversity and divergence patterns that may suggest past actions of positive selection along chromosome maps, and to compare lists of suspected candidate genes under random gene sets to test for the overrepresentation of these patterns among gene categories. Both applications of the algorithm have already been used in published studies. Here we present a publicly available, open source program that will serve as a useful tool for preliminary scans of selection using worldwide databases of human genetic variation, as well as population datasets for many non-human species, from which such data is rapidly emerging with the advent of new genotyping and sequencing technologies