8 research outputs found
Lean body mass associated with upper body strength in healthy older adults while higher body fat limits lower extremity performance and endurance
Impaired strength adversely influences an older person\u27s ability to perform activities of daily living. A cross-sectional study of 117 independently living men and women (age = 73.4 9.4 year; body mass index (BMI) = 27.6 4.8 kg/m2) aimed to assess the association between body composition and: (1) upper body strength (handgrip strength, HGS); (2) lower extremity performance (timed up and go (TUG) and sit to stand test (STS)); and (3) endurance (6-minute walk (SMWT). Body composition (% fat; lean body mass (LBM)) was assessed using bioelectrical impedance. Habitual physical activity was measured using the Minnesota Leisure Time Physical Activity Questionnaire (MLTPA) and dietary macronutrient intake, assessed using 24 h recalls and 3-day food records. Regression analyses included the covariates, protein intake (g/kg), MLTPA, age and sex. For natural logarithm (Ln) of right HGS, LBM (p \u3c 0.001) and % body fat (p \u3c 0.005) were significant (r2 = 46.5%; p \u3c 0.000). For left LnHGS, LBM (p \u3c 0.000), age (p = 0.036), protein intake (p = 0.015) and LnMLTPA (p = 0.015) were significant (r2 = 0.535; p \u3c 0.000). For SMW, % body fat, age and LnMLTPA were significant (r2 = 0.346; p \u3c 0.000). For STS, % body fat and age were significant (r2 = 0.251; p \u3c 0.000). LBM is a strong predictor of upper body strength while higher % body fat and lower physical activity are associated with poorer outcomes on tests of lower extremity performance
Natural Killer Cell Signal Integration Balances Synapse Symmetry and Migration
Imaging immune surveillance by natural killer (NK) cells has revealed that integration of activating and inhibitory signals determines whether or not NK cells stop to kill the target cell or retain a migratory configuration
Investigating the use of world knowledge during on-line comprehension in adults with autism spectrum disorder
The on-line use of world knowledge during reading was examined in adults with autism spectrum disorder (ASD). Both ASD and typically developed (TD) adults read sentences that included plausible, implausible and anomalous thematic relations, as their eye movements were monitored. No group differences in the speed of detection of the anomalous violations were found, but the ASD group showed a delay in detection of implausible thematic relations. These findings suggest that there are subtle differences in the speed of world knowledge processing during reading in ASD
Annual crop legumes may not mitigate greenhouse gas emissions because of the high carbon cost of nitrogen fixation
A large uncertainty in constructing grain cropping Life Cycle Assessments (LCAs) is the effect of a particular crop, or sequence of crops, on soil C stocks. We propose that the C cost of legume Nâ‚‚ fixation, estimated to be ca. 20 kg COâ‚‚/kg N fixed, will be expressed as reduced residue C returned to the soil and a possible net loss of soil C. Published pre-farm + on-farm greenhouse gas (GHG) emissions associated with N-fertilised wheat (60N) and canola (100N) and Nâ‚‚-fixing field pea, grown in Australia's southern grains region, were combined with modelled effects of the same crops on soil C stocks. When effects of the crops on soil C were assumed to be neutral, canola had the highest emissions at 840 kg COâ‚‚-e/ha with field pea the lowest (530 kg COâ‚‚-e/ha). When estimated changes in soil C were included in the LCAs, canola's GHG emission were totally offset (-100 kg COâ‚‚-e/ha), compared with a more than doubling of emissions for field pea to 1270 kg COâ‚‚-e/ha. This is somewhat counter-intuitive to current thinking that the substitution of fertiliser N with legume fixed N is an effective strategy for GHG emissions mitigation and highlights the need for simple, accurate methodologies for determining net changes in soil C for individual crops
Greenhouse gas emission reductions in subtropical cereal-based cropping sequences using legumes, DMPP-coated urea and split timings of urea application
To contribute to national greenhouse gas emissions (GHG) reduction targets, grain growers need strategies that minimise emissions associated with grain production. We used life cycle assessments (LCAs) with field-measured production inputs, grain yields and proteins, legume nitrogen (Nâ‚‚) fixation, and soil nitrous oxide (Nâ‚‚O) and methane (CH4) emissions, to explore mitigation strategies in 3-year crop sequences in subtropical Australia. The sequences were: canola plus 80 kg/ha fertiliser nitrogen (80N)-wheat 85N-barley 65N (CaNWtNBaN), chickpea 0N-wheat 85N-barley 5N (CpWtNBa), chickpea 0N-wheat 5N-chickpea 5N (CpWtCp), and chickpea 0N-sorghum 45N (CpSgN). We also assessed the impacts of split fertiliser N application and urea coated with DMPP, a nitrification inhibitor, on the LCA for the CaNWtNBaN sequence. Total pre-farm plus on-farm GHG emissions varied between 915 COâ‚‚-e/ha (CpSgN) and 1890 COâ‚‚-e/ha (CaNWtNBaN). Cumulative Nâ‚‚O emitted over the 3-year study varied between 0.479kg Nâ‚‚O-N/ha (CpWtCp) and 1.400 kg Nâ‚‚O-N/ha (CaNWtNBaN), which constituted 24-44% of total GHG emissions. Fertiliser production accounted for 20% (CpSgN) to 30% (CaNWtNBaN) of total emissions. An extra 4.7 kg COâ‚‚-e/ha was emitted for each additional kg N/ha of applied N fertiliser. Three-year CH4 emissions ranged from 1.04 to 0.98 kg CH4-C/ha. Split N and DMPP strategies could reduce total GHG emissions of CaNWtNBaN by 17 and 28% respectively. Results of the study indicate considerable scope for reducing the carbon footprint of subtropical, dryland grains cropping in Australia
Altered Neocortical Gene Expression, Brain Overgrowth and Functional Over-Connectivity in <i>Chd8</i> Haploinsufficient Mice
Truncating CHD8 mutations are amongst the highest confidence risk factors for autism spectrum disorder (ASD) identified to date. Here, we report that Chd8 heterozygous mice display increased brain size, motor delay, hypertelorism, pronounced hypoactivity, and anomalous responses to social stimuli. Whereas gene expression in the neocortex is only mildly affected at midgestation, over 600 genes are differentially expressed in the early postnatal neocortex. Genes involved in cell adhesion and axon guidance are particularly prominent amongst the downregulated transcripts. Resting-state functional MRI identified increased synchronized activity in cortico-hippocampal and auditory-parietal networks in Chd8 heterozygous mutant mice, implicating altered connectivity as a potential mechanism underlying the behavioral phenotypes. Together, these data suggest that altered brain growth and diminished expression of important neurodevelopmental genes that regulate long-range brain wiring are followed by distinctive anomalies in functional brain connectivity in Chd8+/- mice. Human imaging studies have reported altered functional connectivity in ASD patients, with long-range under-connectivity seemingly more frequent. Our data suggest that CHD8 haploinsufficiency represents a specific subtype of ASD where neuropsychiatric symptoms are underpinned by long-range over-connectivity