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The authors, through a consultancy with the Caribbean Child Development Centre, the University of the West Indies Open Campus, sought to identify comprehensive parent support programmes and policies in the healthcare sector in non-Spanish-speaking Caribbean countries. As mapping researchers, the authors were contracted to map policies and programmes in the healthcare sector whose aims were to support both family wellbeing and children's healthy development. A review of the existing literature about parenting practices and parenting support programming in the Caribbean was conducted. A catalogue of existing programmes and policies in non-Spanish speaking Caribbean countries was compiled using relevant documents and interviews from primary sources involved in the programmes and the development and implementation of policies. This article outlines the trends identified during the interviews and mapping exercise.

Nitrification inhibitors (NIs) such as 3,4,-dimethylpyrazolc phosphate (DMPP), are used to suppress the abundance of ammonia-oxidising micro-organisms responsible for nitrification. In agriculture, NIs are used to retain soil mineral nitrogen (N) as ammonium to minimise the risk of losses of N from agricultural soils. It is currently unclear whether DMPP-induced nitrification inhibition can prevent losses of N from the light soils prevalent across the main rain-fed cropping regions of Western Australia, or whether it can improve the productivity or N uptake by broadacre crops such as wheat. Herein, we report on a series of glasshouse and field studies that examined the effect of applications of DMPP in conjunction with urea (as ENTEC urea; Incitec Pivot, Melbourne, Vie., Australia) on: (1) soil nitrification rates; (2) the abundance of ammonia-oxidising bacteria and archaea (AOB and AOA respectively); and (3) wheat performance (grain yield, protein content and N accumulation). A glasshouse study demonstrated that DMPP inhibited nitrification (for up to-40 days after application) and reduced the abundance of AOB (by 50%), but had no effect on AOA abundance, wheat grain yield or protein content at any fertiliser N rate. Across six field experiments, DMPP also limited nitrification rates and reduced AOB abundance for approximately the first 40 days after application. However, by the end of the growing season, DMPP use had not increased soil mineral N resources or impaired AOB abundance compared with urea-only applications. In addition, DMPP had no effect on AOA abundance in any trial and did not improve crop performance in most trials. Additional keywords: ammonia-oxidising archaea (AOA), ammonia-oxidising bacteria (AOB), ammonium, ENTEC, nitrate, yield., Introduction Nitrogen (N) is a key component of plant amino and nucleic acids, and is the basis of dietary N (protein) for all animals, including humans. Consequently, the supply of [...]

The effectiveness of the nitrification inhibitor 3,4,-dimethylpyrazole phosphate (DMPP) on sandy soils containing low nitrifying microbial abundance has not been established. Two coarse-grained soils, representative of Western Australia's agricultural zones, were incubated with 100 mg N [kg.sup.-1] soil, added as either urea, urea + DMPP or urea + nitrapyrin as an alternative nitrification inhibitor for comparative purposes. Ammonium (N[H.sub.4.sup.+]) and nitrate (N[O.sub.3.sup.-]) concentrations, potential nitrification rates (PNR) and the abundance of ammonia-oxidising bacteria (AOB) and archaea (AOA) were measured over time. Interactions between soil type and inhibitor type altered the extent of nitrification observed in these soils. When N was supplied as urea alone, N[H.sub.4.sup.+]-N concentrations decreased from 100 mg N [kg.sup.-1] soil to approximately 20 mg N [kg.sup.-1] soil in the high nutrient soil (Williams) and approximately 60 mg N [kg.sup.-1] soil in the low nutrient soil (Vasse). These differences were reflected in AOB abundance, which was higher (~105 gene copies [g.sup.-1] soil) in Williams soil than in Vasse soil (< [10.sup.4] gene copies [g.sup.-1] soil). This difference could have been attributable to differences in soil pH between Williams and Vasse (5.4 vs 4.0 respectively) and/or copper (Cu) availability (~1.5 vs ~0.5 mg Cu [kg.sup.-1] soil respectively), both of which have been demonstrated to reduce AOB abundance or limit nitrification. On the Williams soil, DMPP limited nitrification, resulting in approximately 80 mg N [kg.sup.-1] soil being retained as N[H.sub.4.sup.+]-N. Nitrapyrin was similarly effective for the first 56 days of incubation, but declined considerably in effectiveness between Days 56 and 100. Changes in soil nitrification rates were accompanied by changes in AOB abundance, which was below [10.sup.3] gene copies [g.sup.-1] soil when nitrification was impaired. Both DMPP and nitrapyrin inhibit nitrification via chelating Cu and, because these soils contained low Cu concentrations, it may be possible that interactions between DMPP, naturally low abundance of AOB and low Cu availability facilitated the long-term inhibition of nitrification in these soils. Additional keywords: ammonia-oxidising archaea (AOA), ammonia-oxidising bacteria (AOB), ammonium, mineral nitrogen, nitrapyrin, nitrate, potential nitrification rates (PNR)., Introduction Currently approximately 100 Tg (million tonnes) of fertiliser nitrogen (N) is applied globally each year to agricultural soils (Fischer et al. 2012). On average, In an attempt to minimise [...]

Ammonia-oxidising archaea (AOA) have recently been described as having an important role in soil nitrification. However, published data on factors which influence their distribution and their impact on a soil's potential nitrification rates (PNR) are sparse, particularly compared with the amount of information available regarding ammonia-oxidising bacteria (AOB). This study had two aims. First, to investigate which environmental factors affect the AOA : AOB ratio in soils from two agricultural regions, and second, to explore whether the abundance of either AOA or AOB correlated with PNR. Samples were collected from 45 sites within the cropping regions of Western Australia and South Australia. Soils were tested for pH, N[H.sub.4.sup.+]/N[O.sub.3.sup.-], organic carbon (C), total nitrogen (N), C : N ratio, PNR, and electrical conductivity. Climate data were obtained from the Queensland Climate Change Centre for Excellence SILO website. Abundances of AOA and AOB were measured using real-time PCR quantification of the gene encoding the ammonia monooxygenase enzyme (amoA). Multivariate statistical analysis was applied to assess correlations between PNR, soil properties, and abundance of AOA or AOB. In the majority samples AOA were present, but their abundance, and the AOA : AOB ratio, varied considerably between sites. Multivariate analysis showed that the distribution of AOA and AOB and the AOA : AOB ratio were strongly correlated with climatic and seasonal factors. Sites where samples were collected during dry, hot periods tended to be AOA-dominated, whereas samples collected during cool, wet periods tended to be AOB-dominated or have equal abundances of AOA and AOB. The PNRs were correlated with total N content, organic C content, and soil pH. There was no clear correlation between AOA or AOB and PNR. This study shows that both AOA and AOB are widespread in Western Australian and South Australian soils and their abundance and ratio are affected by climate and season. It also shows that PNR is more strongly influenced by soil fertility factors than by the AOA:AOB ratio. Additional keywords: ammonia-oxidising archaea, ammonia-oxidising bacteria, amoA, distribution, potential nitrification rate., Introduction Nitrification is the microbially mediated conversion of reduced forms of nitrogen, i.e. ammonia (N[H.sup.3]) and ammonium (N[H.sub.4.sup.+]), into oxidised forms, e.g. nitrate (N[O.sub.3.sup.-]) and nitrite (N[O.sub.2.sup.-]). The first and [...]

The abundances of ammonia-oxidising archaea (AOA) and ammonia-oxidising bacteria (AOB) in soils underlying pastures in the south-west of Western Australia (WA) were investigated. samples were collected from irrigated pastures and one unmanaged (driveway) area during December 2009. Archaeal and bacterial ammonia monooxygenase (amoA) genes were quantified using real-time PCR, and the diversity of the archaeal amoA genes was investigated using denaturing gradient gel electrophoresis (PCR-DGGE). AOA amoA gene copies outnumbered AOB in all samples. Numbers ofarchaeal amoA genes ranged from 4.1 E+01 to 1.34E+05 gene copies/ng soil DNA. Bacterial amoA genes were below detection limits at three of the four sample sites and ranged from 8.9E+01 to 6.7E+02 gene copies/rig soil DNA at the remaining site. Potential nitrification rates (PNR) were not correlated with AOA or AOB gene abundance, but high PNR only occurred at the site with measureable numbers of AOB. The DGGE analysis revealed that the AOA community was diverse and variability in banding patterns was significantly affected by both site and depth (P< 0.05). Statistical analysis matching biological variation (AOA amoA genotypes) to environmental variables (BEST analysis) revealed that pH was the key driver of AOA community structure (p-0.72; P = 0.005). Soil pH was also inversely correlated to abundance of AOA amoA genes in soil (p = 0.8; P=0.003). This study has shown that AOA are important members of the nitrogencycling community in acidic WA pasture soils, and likely in the wider agricultural soils of WA. Additional keywords: ammonia oxidation, acidic soils, ammonia-oxidising archaea, ammonia-oxidising bacteria, amoA, nitrification., Introduction The microbially mediated conversion of ammonium-nitrogen (N[H.sup.4.sup.+]-N) to nitrite-N (N[O.sub.2.sup.-]-N) is the first step in the process of nitrification, i.e. the oxidation of N[H.sup.4.sup.+] to nitrate (N[O.sub.3]) (Focht and [...]

Fisherman Islands is an area of reclaimed land at the mouth of the Brisbane River in Queenshmd, Australia. Ongoing groundwater monitoring has found elevated concentrations of hydrogen sulfide ([H.sub.2]S) in the groundwater on the island. The presence of [H.sub.2]S on Fisherman Islands is of concern because of its toxic nature, the potential for acid sulfate soil formation, and its noxious odor. The aim of this study was to identify the sources of [H.sub.2]S within the groundwater on Fisherman Islands. It was hypothesized that the [H.sub.2]S is being formed by sulfate reducing bacteria acting on sulfate from seawater, rather than the introduction of sulfide with the dredge sediments. Groundwater and soil samples were collected and analyzed for sulfide, sulfate, and organic carbon contents. Elevated concentrations of sulfides coincide with elevated concentrations of sulfate in the groundwater and elevated concentrations of organic carbon in the sediments, supporting the hypothesis that sulfide formation is the result of heterotrophic, sulfate reducing organisms. CE Database subject headings: Ground-water chemistry; Soil chemistry; Dredged spoil; Hydrogen sulfides; Land reclamation.

A range of plant species produce root exudates that inhibit ammonia-oxidizing microorganisms. This biological nitrification inhibition (BNI) capacity can decrease N loss and increase N uptake from the rhizosphere. This study sought evidence for the existence and magnitude of BNI capacity in canola (Brassica napus). Seedlings of three canola cultivars, Brachiaria humidicola (BNI positive) and wheat (Triticum aestivum) were grown in a hydroponic system. Root exudates were collected and their inhibition of the ammonia oxidizing bacterium, Nitrosospira multiformis, was tested. Subsequent pot experiments were used to test the inhibition of native nitrifying communities in soil. Root exudates from canola significantly reduced nitrification rates of both N. multiformis cultures and native soil microbial communities. The level of nitrification inhibition across the three cultivars was similar to the well-studied high-BNI species B. humidicola. BNI capacity of canola may have implications for the N dynamics in farming systems and the N uptake efficiency of crops in rotational farming systems. By reducing nitrification rates canola crops may decrease N losses, increase plant N uptake and encourage microbial N immobilization and subsequently increase the pool of organic N that is available for mineralization during the following cereal crops. [ABSTRACT FROM AUTHOR]

Phytopathogenic members of the Sclerotinia genus cause widespread disease across a broad range of economically important crops. In particular, Sclerotinia sclerotiorum is considered one of the most destructive and cosmopolitan of plant pathogens. Here, were review the epidemiology of the pathogen, its economic impact on agricultural production, and measures employed toward control of disease. We review the broad approaches required to tackle Sclerotinia diseases and include cultural practices, crop genetic resistance, chemical fungicides, and biological controls. We highlight the benefits and drawbacks of each approach along with recent advances within these controls and future strategies. [ABSTRACT FROM AUTHOR]

Engineering perishable crops for use in indoor farms promises to expand the adoption of this high-yielding, efficient means of food production. [ABSTRACT FROM AUTHOR]

The authors, through a consultancy with the Caribbean Child Development Centre, the University of the West Indies Open Campus, sought to identify comprehensive parent support programmes and policies in the healthcare sector in non-Spanish-speaking Caribbean countries. As mapping researchers, the authors were contracted to map policies and programmes in the healthcare sector whose aims were to support both family wellbeing and children’s healthy development. A review of the existing literature about parenting practices and parenting support programming in the Caribbean was conducted. A catalogue of existing programmes and policies in non-Spanish speaking Caribbean countries was compiled using relevant documents and interviews from primary sources involved in the programmes and the development and implementation of policies. This article outlines the trends identified during the interviews and mapping exercise. [ABSTRACT FROM AUTHOR]

ABSTRACT It is well established that metabolic pathways in the fermentation of organic waste are primarily controlled by dissolved H2 concentrations, but there is no reported study that compares observed and predicted shifts in fermentation pathways induced by manipulating the dissolved H2 concentration. A perfusion system is presented that was developed to control dissolved H2 concentrations in the continuous fermentation of glucose by a culture highly enriched towards Thermoanaerobacterium thermosaccharolyticum (86 ± 9% relative abundance) from an originally diverse consortia in the leachate of a laboratory digester fed with municipal solid waste. Media from a 2.5 L CSTR was drawn through sintered steel membrane filters to retain biomass, allowing vigorous sparging in a separate chamber without cellular disruption. Through a combination of sparging and variations in glucose feeding rate from 0.8 to 0.2 g/L/d, a range of steady state fermentations were performed with dissolved H2 concentrations as low as an equivalent equilibrated H2 partial pressure of 3 kPa. Trends in product formation rates were simulated using a H2 regulation partitioning model. The model correctly predicted the direction of products redistribution in response to H2 concentration changes and the acetate and butyrate formation rates when H2 concentrations were less than 6 kPa. However, the model over-estimated acetate, ethanol and butanol productions at the expense of butyrate production at higher H2 concentrations. The H2 yield at the lowest dissolved H2 concentration was 2.67 ± 0.08 mol H2/mol glucose, over 300% higher than the yield achieved in a CSTR operated without sparging. Biotechnol. Bioeng. 2015;112: 1177-1186. © 2014 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]