Maternal nutritional status, C1 metabolism and offspring DNA methylation: a review of current evidence in human subjects.

: Evidence is growing for the long-term effects of environmental factors during early-life on later disease susceptibility. It is believed that epigenetic mechanisms (changes in gene function not mediated by DNA sequence alteration), particularly DNA methylation, play a role in these processes. This paper reviews the current state of knowledge of the involvement of C1 metabolism and methyl donors and cofactors in maternal diet-induced DNA methylation changes in utero as an epigenetic mechanism. Methyl groups for DNA methylation are mostly derived from the diet and supplied through C1 metabolism by way of choline, betaine, methionine or folate, with involvement of riboflavin and vitamins B6 and B12 as cofactors. Mouse models have shown that epigenetic features, for example DNA methylation, can be altered by periconceptional nutritional interventions such as folate supplementation, thereby changing offspring phenotype. Evidence of early nutrient-induced epigenetic change in human subjects is scant, but it is known that during pregnancy C1 metabolism has to cope with high fetal demands for folate and choline needed for neural tube closure and normal development. Retrospective studies investigating the effect of famine or season during pregnancy indicate that variation in early environmental exposure in utero leads to differences in DNA methylation of offspring. This may affect gene expression in the offspring. Further research is needed to examine the real impact of maternal nutrient availability on DNA methylation in the developing fetus

Tasmanian Midlands options to improve biodiversity governance arrangements

Conserving landscapes rich in biodiversity requires long-term planning and understanding of how social and ecological systems co-evolve. How such landscapes are governed (that is, the structures and processes that determine who has influence, who decides, and how decision-makers are held accountable) is pivotal to the long-term conservation of this biodiversity. Being able to govern across diverse landscapes, like the Tasmanian Midlands, where there are multiple landholders and multiple values, is a challenging task. Governance can improve biodiversity outcomes indirectly by enabling decision-making and management actions that are more responsive to environmental and social conditions. Better biodiversity outcomes could mean improving the extent and/or condition of biodiversity values or reducing the threat to those values. For example, this could be an increase in extent and improvement in condition of lowland native grasslands. Better outcomes might also include a decline in threats from invasive species or a land use mix that is more favourable to conservation. The process to generate the two governance options presented in this document is pictured on the following page. The research team developed two initial proposals for governance arrangements through an analysis of findings from key informant interviews, complemented by a review of the literature to identify whether best practice case studies elsewhere could offer innovative ways forward. The two proposed options were then discussed at three focus groups: one that prioritised input from Tasmanian Midlands landholders and their representative organisations; one focused on input from the Tasmanian state government staff; and one that focused on input from Australian Government staff

Do topical repellents divert mosquitoes within a community? Health equity implications of topical repellents as a mosquito bite prevention tool.

OBJECTIVES: Repellents do not kill mosquitoes--they simply reduce human-vector contact. Thus it is possible that individuals who do not use repellents but dwell close to repellent users experience more bites than otherwise. The objective of this study was to measure if diversion occurs from households that use repellents to those that do not use repellents. METHODS: The study was performed in three Tanzanian villages using 15%-DEET and placebo lotions. All households were given LLINs. Three coverage scenarios were investigated: complete coverage (all households were given 15%-DEET), incomplete coverage (80% of households were given 15%-DEET and 20% placebo) and no coverage (all households were given placebo). A crossover study design was used and coverage scenarios were rotated weekly over a period of ten weeks. The placebo lotion was randomly allocated to households in the incomplete coverage scenario. The level of compliance was reported to be close to 100%. Mosquito densities were measured through aspiration of resting mosquitoes. Data were analysed using negative binomial regression models. FINDINGS: Repellent-users had consistently fewer mosquitoes in their dwellings. In villages where everybody had been given 15%-DEET, resting mosquito densities were fewer than half that of households in the no coverage scenario (Incidence Rate Ratio [IRR]=0.39 (95% confidence interval [CI]: 0.25-0.60); p<0.001). Placebo-users living in a village where 80% of the households used 15%-DEET were likely to have over four-times more mosquitoes (IRR=4.17; 95% CI: 3.08-5.65; p<0.001) resting in their dwellings in comparison to households in a village where nobody uses repellent. CONCLUSIONS: There is evidence that high coverage of repellent use could significantly reduce man-vector contact but with incomplete coverage evidence suggests that mosquitoes are diverted from households that use repellent to those that do not. Therefore, if repellents are to be considered for vector control, strategies to maximise coverage are required

Measuring hearing in wild beluga whales

Author Posting. © The Author(s), 2016. This is the author's version of the work. It is posted here by permission of Springer for personal use, not for redistribution. The definitive version was published in "The Effects of Noise on Aquatic Life II," edited by Arthur N. Popper, Anthony Hawkins, 729-735. New York, NY: Springer, 2016. doi: 10.1007/978-1-4939-2981-8_88.We measured the hearing abilities of seven wild beluga whales (Delphinapterus leucas) during a collection-and-release experiment in Bristol Bay, AK, USA. Here we summarize the methods and initial data from one animal, discussing the implications of this experiment. Audiograms were collected from 4-150 kHz. The animal with the lowest threshold heard best at 80 kHz and demonstrated overall good hearing from 22-110 kHz. The robustness of the methodology and data suggest AEP audiograms can be incorporated into future collection-and-release health assessments. Such methods may provide high-quality results for multiple animals facilitating population-level audiograms and hearing measures in new species.Project funding and field support provided by Georgia Aquarium and the National Marine Mammal Laboratory of the Alaska Fisheries Science Center (NMML/AFSC). Field work also supported by National Marine Fisheries Service Alaska Regional Office (NMFS AKR), WHOI Arctic Research Initiative, WHOI Ocean Life Institute, U.S. Fish and Wildlife Service, Bristol Bay Native Association, Alaska SeaLife Center, Shedd Aquarium and Mystic Aquarium. Audiogram analyses were funded by the Office of Naval Research award number N000141210203 (from Michael Weise)

A recent whole-genome duplication divides populations of a globally-distributed microsporidian

This is the final version of the article. Available from Oxford University Press via the DOI in this record.The Microsporidia are a major group of intracellular fungi and important parasites of animals including insects, fish, and immunocompromised humans. Microsporidian genomes have undergone extreme reductive evolution but there are major differences in genome size and structure within the group: some are prokaryote-like in size and organisation (<3 Mb of gene-dense sequence) whilst others have more typically eukaryotic genome architectures. To gain fine-scale, population-level insight into the evolutionary dynamics of these tiny eukaryotic genomes, we performed the broadest microsporidian population genomic study to date, sequencing geographically isolated strains of Spraguea, a marine microsporidian infecting goosefish worldwide. Our analysis revealed that population structure across the Atlantic Ocean is associated with a conserved difference in ploidy, with American and Canadian isolates sharing an ancestral whole genome duplication that was followed by widespread pseudogenisation and sorting-out of paralogue pairs. Whilst past analyses have suggested de novo gene formation of microsporidian-specific genes, we found evidence for the origin of new genes from noncoding sequence since the divergence of these populations. Some of these genes experience selective constraint, suggesting the evolution of new functions and local host adaptation. Combining our data with published microsporidian genomes, we show that nucleotide composition across the phylum is shaped by a mutational bias favouring A and T nucleotides, which is opposed by an evolutionary force favouring an increase in genomic GC content. This work reveals ongoing dramatic reorganisation of genome structure and the evolution of new gene functions in modern microsporidians despite extensive genomic streamlining in their common ancestor.The authors would like to thank John Brookfield and David Studholme for helpful discussions. This work was supported by a Marie Curie Intra-European postdoctoral fellowship (T.A.W.) and the European Research Council Advanced Investigator Programme and the Wellcome Trust (grant numbers ERC- 2010- AdG-268701 045404 to T.M.E.) It is also supported by a Royal Society University Research Fellowship (B.A.P.W.)

Interleukin 7 from Maternal Milk Crosses the Intestinal Barrier and Modulates T- Cell Development in Offspring

Background Breastfeeding protects against illnesses and death in hazardous environments, an effect partly mediated by improved immune function. One hypothesis suggests that factors within milk supplement the inadequate immune response of the offspring, but this has not been able to account for a series of observations showing that factors within maternally derived milk may supplement the development of the immune system through a direct effect on the primary lymphoid organs. In a previous human study we reported evidence suggesting a link between IL-7 in breast milk and the thymic output of infants. Here we report evidence in mice of direct action of maternally-derived IL-7 on T cell development in the offspring. Methods and Findings  We have used recombinant IL-7 labelled with a fluorescent dye to trace the movement in live mice of IL-7 from the stomach across the gut and into the lymphoid tissues. To validate the functional ability of maternally derived IL- 7 we cross fostered IL-7 knock-out mice onto normal wild type mothers. Subsets of thymocytes and populations of peripheral T cells were significantly higher than those found in knock-out mice receiving milk from IL-7 knock-out mothers. Conclusions/Significance Our study provides direct evidence that interleukin 7, a factor which is critical in the development of T lymphocytes, when maternally derived can transfer across the intestine of the offspring, increase T cell production in the thymus and support the survival of T cells in the peripheral secondary lymphoid tissue

An evaluation of strategies used by the Landscapes and Policy Hub to achieve interdisciplinary and transdisciplinary research

The report presents an evaluation of the Landscapes and Policy Hub's approach to interdisciplinary and transdisciplinary research. The hub was a national, four year, $15 million collaborative research program. The focus of the evaluation was for researchers to reflect on the effectiveness of strategies used by the hub to facilitate interdisciplinarity (where researchers from different disciplines work together to solve problems) and transdisciplinarity (where researchers from different disciplines work in partnership with research users to solve problems). The evaluation was commissioned in the final phase of the hub’s life in the interests of improving performance of future interdisciplinary and transdisciplinary research. It was based on a number of strategies that had been implemented by the hub to encourage and facilitate interdisciplinary research occurring in partnership with research users. The aim of the evaluation was to improve performance of future interdisciplinary and transdisciplinary research. Six recommendations are presented

Observation of An Evolving Magnetic Flux Rope Prior To and During A Solar Eruption

Explosive energy release is a common phenomenon occurring in magnetized plasma systems ranging from laboratories, Earth's magnetosphere, the solar corona and astrophysical environments. Its physical explanation is usually attributed to magnetic reconnection in a thin current sheet. Here we report the important role of magnetic flux rope structure, a volumetric current channel, in producing explosive events. The flux rope is observed as a hot channel prior to and during a solar eruption from the Atmospheric Imaging Assembly (AIA) telescope on board the Solar Dynamic Observatory (SDO). It initially appears as a twisted and writhed sigmoidal structure with a temperature as high as 10 MK and then transforms toward a semi-circular shape during a slow rise phase, which is followed by fast acceleration and onset of a flare. The observations suggest that the instability of the magnetic flux rope trigger the eruption, thus making a major addition to the traditional magnetic-reconnection paradigm.Comment: 13 pages, 3 figure

Fast Ensemble Smoothing

Smoothing is essential to many oceanographic, meteorological and hydrological applications. The interval smoothing problem updates all desired states within a time interval using all available observations. The fixed-lag smoothing problem updates only a fixed number of states prior to the observation at current time. The fixed-lag smoothing problem is, in general, thought to be computationally faster than a fixed-interval smoother, and can be an appropriate approximation for long interval-smoothing problems. In this paper, we use an ensemble-based approach to fixed-interval and fixed-lag smoothing, and synthesize two algorithms. The first algorithm produces a linear time solution to the interval smoothing problem with a fixed factor, and the second one produces a fixed-lag solution that is independent of the lag length. Identical-twin experiments conducted with the Lorenz-95 model show that for lag lengths approximately equal to the error doubling time, or for long intervals the proposed methods can provide significant computational savings. These results suggest that ensemble methods yield both fixed-interval and fixed-lag smoothing solutions that cost little additional effort over filtering and model propagation, in the sense that in practical ensemble application the additional increment is a small fraction of either filtering or model propagation costs. We also show that fixed-interval smoothing can perform as fast as fixed-lag smoothing and may be advantageous when memory is not an issue

An approximate model for cancellous bone screw fixation

This is the author's accepted manuscript. The final published article is available from the link below. Copyright @ 2013 Taylor & Francis.This paper presents a finite element (FE) model to identify parameters that affect the performance of an improved cancellous bone screw fixation technique, and hence potentially improve fracture treatment. In cancellous bone of low apparent density, it can be difficult to achieve adequate screw fixation and hence provide stable fracture fixation that enables bone healing. Data from predictive FE models indicate that cements can have a significant potential to improve screw holding power in cancellous bone. These FE models are used to demonstrate the key parameters that determine pull-out strength in a variety of screw, bone and cement set-ups, and to compare the effectiveness of different configurations. The paper concludes that significant advantages, up to an order of magnitude, in screw pull-out strength in cancellous bone might be gained by the appropriate use of a currently approved calcium phosphate cement