Defining the Placental Barrier during Toxoplasma gondii Infection

Toxoplasma gondii is a major source of congenital disease worldwide, but the cellular and molecular factors associated with its vertical transmission are largely unknown. In humans, the placenta forms the key interface between the maternal and fetal compartments and forms the primary barrier that restricts the hematogenous spread of microorganisms. This dissertation describes both the identification of two mechanisms of placental syncytiotrophoblast resistance to T. gondii infection and a preliminary understanding of the CCL22 response induced by the Toxoplasma dense granule protein GRA28. Collectively, these findings provide new insights into (1) protective role of the syncytiotrophoblast during T. gondii infection, (2) interferon-gamma independent restriction of T. gondii growth, and (3) parasite-directed manipulation of the intercellular communication between the placenta and components of the maternal immune system

The availability and geographic location of open-source food composition data used to estimate micronutrient intakes in sub-Saharan Africa: A scoping review

Background Estimates of dietary micronutrient intakes rely on food composition data. The nutrient composition of foods varies spatially with potentially large effects on dietary micronutrient intakes. This review assessed the availability and geographic origin of five minerals (calcium, iron, iodine, selenium and zinc) in publicly available food composition tables/databases (FCTs) for use in sub-Saharan Africa (SSA). Methods A scoping review was conducted following PRISMA guidelines, in which four databases (MEDLINE, Embase, Global Health and Africa Wide Information) and four online resources were searched to identify published FCTs for use in SSA. Metadata were reviewed to identify the geographic origin of composition values for selected foods. Results Nineteen publicly available FCTs were identified, with the highest geographic coverage in Eastern Africa (45% of countries) and lowest coverage in Central Africa (12% of countries). Iodine and selenium were reported in four and six FCTs, respectively, while iron and calcium were included in ≥ 18 FCTs. More than 60% of nutrient values were borrowed from other FCTs. The geographic origin of 22% of mineral values were documented. Conclusions Limited local food composition analytical data is available, for estimating mineral intakes of SSA populations, with poor documentation of the data sources and the geographic origins of samples. New data structures and improved metadata are required to capture and report geographic information in publicly available FCTs, and to accommodate a new generation of spatially-resolved food composition data

An efficient algorithm for computing the Baker-Campbell-Hausdorff series and some of its applications

We provide a new algorithm for generating the Baker--Campbell--Hausdorff (BCH) series Z = \log(\e^X \e^Y) in an arbitrary generalized Hall basis of the free Lie algebra $\mathcal{L}(X,Y)$ generated by $X$ and $Y$. It is based on the close relationship of $\mathcal{L}(X,Y)$ with a Lie algebraic structure of labeled rooted trees. With this algorithm, the computation of the BCH series up to degree 20 (111013 independent elements in $\mathcal{L}(X,Y)$) takes less than 15 minutes on a personal computer and requires 1.5 GBytes of memory. We also address the issue of the convergence of the series, providing an optimal convergence domain when $X$ and $Y$ are real or complex matrices.Comment: 30 page

Liver copper concentrations in cull cattle in the UK: are cattle being copper loaded?

With the release of the Department for the Environment, Food and Rural Affairs/Advisory Committee on Animal Feed Guidance Note for Supplementing Copper to Bovines it was noted that the current copper status of the national herd was not known. Liver samples were recovered from 510 cull cattle at a single abattoir across a period of three days. The samples were wet-ashed and liver copper concentrations determined by inductively coupled plasma mass spectrometry analysis. Breed, age and previous location information were obtained from the British Cattle Movement Service. Dairy breeds had higher liver copper concentrations than beef breeds. Holstein-Friesian and ‘other’ dairy breeds had 38.3 per cent and 40 per cent of cattle above the Animal Health and Veterinary Laboratories Agency (AHVLA) reference range (8000 µmol/kg dry matter), respectively, whereas only 16.9 per cent of animals in the combined beef breeds exceeded this value. It was found that underlying topsoil copper concentration was not related to liver copper content and that age of the animal also had little effect on liver concentration. In conclusion, over 50 per cent of the liver samples tested had greater-than-normal concentrations of copper with almost 40 per cent of the female dairy cattle having liver copper concentrations above the AHVLA reference range, indicating that a significant proportion of the UK herd is at risk of chronic copper toxicity

Lability of Pb in soil: effects of soil properties and contaminant source

Environmental Context: There is growing concern that lead (Pb) in the environment may cause adverse health effects in human populations. We investigated the combined use of isotopic abundance and isotopic dilution to show how the origins of soil Pb and soil characteristics affect lability. Soil pH and soil Pb content are the dominant controls on Pb lability; the lability of recent petrol-derived Pb is similar to that of other sources in urban soils but greater than geogenic Pb in rural roadside topsoils. Lability of lead (Pb) in soils is influenced by both soil properties and source(s) of contamination. We investigated factors controlling Pb lability in soils from (i) land adjacent to a major rural road, (ii) a sewage processing farm and (iii) an archive of the geochemical survey of London. We measured isotopically exchangeable Pb (E-values; PbE), phase fractionation of Pb by a sequential extraction procedure (SEP) and inferred source apportionment from measured Pb isotopic ratios. Isotopic ratios (206Pb/207Pb and 208Pb/207Pb) of total soil Pb fell on a mixing line between those of petrol and UK coal or Pb ore. The main determinant of the isotopically exchangeable Pb fraction (%E-value) was soil pH: %E-values decreased with increasing pH. In rural roadside topsoils and there was also evidence that, petrol-derived Pb remained more labile (35%) than Pb from soil parent material (27%). However, in biosolid-amended and London soils %E-values were low (c. 25%), covered a restricted range, and showed no clear evidence of source-dependent lability

Zinc-enriched fertilisers as a potential public health intervention in Africa

Background In this review, we examine the potential of Zn-enriched fertilisers to alleviate human dietary Zn deficiency. The focus is on ten African countries where dietary Zn supply is low and where fertiliser subsidies are routinely deployed on cereal crops. Scope Dietary Zn supply and deficiency prevalence were quantified from food supply and composition data. Typical effects of soil (granular) and foliar Zn applications on Zn concentrations in maize (Zea mays L.), rice (Oryza sativa L.) and wheat (Triticum aestivum L.) grains were based on a systematic literature review. Reductions in disease burdens attributable to Zn deficiency and cost-effectiveness were estimated using a disability-adjusted life years (DALYs) approach. Conclusions Baseline Zn supply in 2009 ranged from 7.1 (Zambia) to 11.9 (Mali) mg capita−1 day−1; prevalence of Zn deficiency ranged from 24 (Nigeria) to 66 % (Zambia). In reviewed studies, soil Zn application led to an increase in median Zn concentration in maize, rice and wheat grains of 23, 7 and 19 %; foliar application led to increases of 30, 25 and 63 %. Enriching granular fertilisers within current subsidy schemes would be most effective in Malawi, reducing DALYs lost due to Zn deficiency by 10 %. The cost per DALY saved ranged from US$624 to 5893 via granular fertilisers and from US$ 46 to 347 via foliar fertilisers. Foliar applications are likely to be more cost effective than soil applications due to fixation of Zn in the soil but may be more difficult to deploy. Zinc fertilisation is likely to be less cost-effective than breeding in the longer term although other micronutrients such as selenium could be incorporated

Funding archive services in England and Wales: institutional realities and professional perceptions

This article reports on two related pieces of collaborative research carried out by the International Centre for Archives and Records Management Research in the Department of Information Studies at University College London, The National Archives, and the National Council on Archives between 2007 and 2012, which together investigated how archives in England and Wales are funded and the perceptions of funders and fundraising amongst archivists. Both pieces of research aimed to establish the institutional realities of funding and the funding mix for archive services, identifying which funding sources and fundraising techniques are well embedded and which are underdeveloped within the sector. The research projects also considered professional perceptions about fundraising and funding, in particular about funding from the Heritage Lottery Fund. Although not linked originally, the findings of these two projects throw light on an under-researched area of funding of archive services, and so the results of both projects are presented in a single article. The article also outlines some further research and professional development needs; suggests a target for a more robust funding mix and also that fundraising skills should properly form a part of the professional competencies framework

Demonstration of a light-redirecting skylight system at the Palm Springs Chamber of Commerce

As part of a demonstration project to provide a comprehensive energy upgrade to a 294 m{sup 2} (3168 ft{sup 2}) commercial building, an advanced skylight design was developed using optical light control materials and geometry to provide daylight to two adjoining offices. The skylight system was developed using outdoor physical model tests and simulation tools Limited on-site measurements and occupant polls were conducted. Market issues were addressed. The skylight systems were found to improve lighting quality and to control excessive daylight illuminance levels compared to a conventional diffusing bubble skylight. Daylighting principles developed in earlier work for vertical glazing systems (light shelves and light pipes) were shown to be applicable in skylight designs at full-scale