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Globally, soils and sediments are affected by the bioturbation activities of benthic species. The consequences of these activities are particularly impactful in intertidal sediment, which is generally anoxic and nutrient‐poor. Mangrove intertidal sediments are of particular interest because, as the most productive forests and one of the most important stores of blue carbon, they provide global‐scale ecosystem services. The mangrove sediment microbiome is fundamental for ecosystem functioning, influencing the efficiency of nutrient cycling and the abundance and distribution of key biological elements. Redox reactions in bioturbated sediment can be extremely complex, with one reaction creating a cascade effect on the succession of respiration pathways. This facilitates the overlap of different respiratory metabolisms important in the element cycles of the mangrove sediment, including carbon, nitrogen, sulphur and iron cycles, among others. Considering that all ecological functions and services provided by mangrove environments involve microorganisms, this work reviews the microbial roles in nutrient cycling in relation to bioturbation by animals and plants, the main mangrove ecosystem engineers. We highlight the diversity of bioturbating organisms and explore the diversity, dynamics and functions of the sediment microbiome, considering both the impacts of bioturbation. Finally, we review the growing evidence that bioturbation, through altering the sediment microbiome and environment, determining a 'halo effect', can ameliorate conditions for plant growth, highlighting the potential of the mangrove microbiome as a nature‐based solution to sustain mangrove development and support the role of this ecosystem to deliver essential ecological services. [ABSTRACT FROM AUTHOR]

Due to the chemico-physical differences between air and water, the transition from aquatic life to the land poses several challenges for animal evolution, necessitating morphological, physiological and behavioural adaptations. Microbial symbiosis is known to have played an important role in eukaryote evolution, favouring host adaptation under changing environmental conditions. We selected mangrove brachyuran crabs as a model group to investigate the prokaryotes associated with the gill of crabs dwelling at different tidal levels (subtidal, intertidal and supratidal). In these animals, the gill undergoes a high selective pressure, finely regulating multiple physiological functions during both animal submersion under and emersion from the periodical tidal events. We hypothesize that similarly to other marine animals, the gills of tidal crabs are consistently colonized by prokaryotes that may quantitatively change along the environmental gradient driven by the tides. Using electron microscopy techniques, we found a thick layer of prokaryotes over the gill surfaces of all of 12 crab species from the mangrove forests of Saudi Arabia, Kenya and South Africa. We consistently observed two distinct morphotypes (rod- and spherical-shaped), positioned horizontally and/or perpendicularly to the gill surface. The presence of replicating cells indicated that the prokaryote layer is actively growing on the gill surface. Quantitative analysis of scanning electron microscopy images and the quantification of the bacterial 16S rRNA gene by qPCR revealed a higher specific abundance of prokaryote cells per gill surface area in the subtidal species than those living in the supratidal zone. Our results revealed a correlation between prokaryote colonization of the gill surfaces and the host lifestyle. This finding indicates a possible role of prokaryote partnership within the crab gills, with potential effects on animal adaptation to different levels of the intertidal gradient present in the mangrove ecosystem. [ABSTRACT FROM AUTHOR]

Nursing homes are the UK's main providers of continuing care and, because modern healthcare systems involve a complex network of providers, it is essential that the benefits of collaborative approaches [...]

The adaptation of sporeformers to extreme environmental conditions is frequently questioned due to their capacity to produce highly resistant endospores that are considered as resting contaminants, not representing populations adapted to the system. In this work, in order to gain a better understanding of bacterial adaptation to extreme habitats, we investigated the phenotypic and genomic characteristics of the halophile Virgibacillus sp. 21D isolated from the seawater-brine interface (SBI) of the MgCl2-saturated deep hypersaline anoxic basin Discovery located in the Eastern Mediterranean Sea. Vegetative cells of strain 21D showed the ability to grow in the presence of high concentrations of MgCl2, such as 14.28% corresponding to 1.5 M. Biolog phenotype MicroArray (PM) was adopted to investigate the strain phenotype, with reference to carbon energy utilization and osmotic tolerance. The strain was able to metabolize only 8.4% of 190 carbon sources provided in the PM1 and PM2 plates, mainly carbohydrates, in accordance with the low availability of nutrients in its habitat of origin. By using in silico DNA-DNA hybridization the analysis of strain 21D genome, assembled in one circular contig, revealed that the strain belongs to the species Virgibacillus dokdonensis. The genome presented compatible solute-based osmoadaptation traits, including genes encoding for osmotically activated glycine-betaine/carnitine/choline ABC transporters, as well as ectoine synthase enzymes. Osmoadaptation of the strain was then confirmed with phenotypic assays by using the osmolyte PM9 Biolog plate and growth experiments. Furthermore, the neutral isoelectric point of the reconstructed proteome suggested that the strain osmoadaptation was mainly mediated by compatible solutes. The presence of genes involved in iron acquisition and metabolism indicated that osmoadaptation was tailored to the iron-depleted saline waters of the Discovery SBI. Overall, both phenomics and genomics highlighted the potential capability of V. dokdonensis 21D vegetative cells to adapt to the environmental conditions in Discovery SBI. [ABSTRACT FROM AUTHOR]

Background Relapses of childhood steroid-sensitive nephrotic syndrome (SSNS) are treated with a 4- to 8- week course of high-dose oral prednisolone, which may be associated with significant adverse effects. There is a clear association between upper respiratory tract infection (URTI) and relapse development. Previous studies in developing nations have suggested that introducing a 5- to 7-day course of daily prednisolone during an URTI may prevent a relapse developing and the need for a treatment course of high-dose prednisolone. The aim of PREDNOS 2 is to evaluate the effectiveness of a 6-day course of daily prednisolone therapy during an URTI in reducing the development of a subsequent relapse in a developed nation. Methods/design The subjects will be 300 children with relapsing SSNS (⩾2 relapses in preceding year), who will be randomised to receive either a 6-day course of daily prednisolone or no change to their current therapy (with the use of placebo to double blind) each time they develop an URTIover 12 months. A strict definition for URTI will be used. Subjects will be reviewed at 3, 6, 9 and 12 months to capture data regarding relapse history, ongoing therapy and adverse effect profile, including behavioural problems and quality of life. A formal health economic analysis will also be performed. The primary end point of the study will be the incidence of URTI-related relapse (3 days of Albustix +++) following the first infection during the 12- month follow-up period. DNA and RNA samples will be collected to identify a potential genetic cause for the disease. Subjects will be recruited from over 100 UK centres with the assistance of the Medicines for Children Research Network. PREDNOS 2 is funded by the National Institute for Health Research Health Technology Assessment Programme (11/129/261) Discussion We propose that PREDNOS 2 will be a pivotal study that will inform the future standard of care for children with SSNS. If it is possible to reduce the disease relapse rate effectively and safely, this will reduce the morbidity and cost associated with drug treatment, notwithstanding hospital admission and parental absence from employment. Trial registration Current Controlled Trials (ISRCTN10900733). [ABSTRACT FROM AUTHOR]

Background: The benefits of breastfeeding are well-recognised. The majority of first-time mothers in the Lao People's Democratic Republic however do not follow WHO guidelines of exclusively breastfeeding for the first six months, and less than half breastfeed for two years. UNICEF identified lack of exclusive breastfeeding as the second highest risk factor for under 5 mortality in Lao PDR, closely following lack of skilled delivery care. This study explored the reasons and influences behind first-time mothers' breastfeeding practices, as well as the role of attitudes, beliefs and experiences in influencing those practices.Methods: A qualitative research design was chosen for this exploratory study. Two districts in Vientiane were selected, and in each district four focus group discussions, two with six first-time mothers and two with health staff were undertaken. In addition, sixteen in-depth interviews with first-time mothers and seven individual key informants were conducted.Results: Participants demonstrated positive attitudes towards breastfeeding and recognised its importance. Despite this, breastfeeding practices were suboptimal. Few exclusively breastfed for the first six months of the baby's life and most of the first-time mothers included in the sample had stopped or planned to stop breastfeeding by the time the infant was 18 months of age. Work was named as one of the main reasons for less than ideal breastfeeding practices. Traditional beliefs and advice from health staff and the first-time mothers' own mothers, were important influences on breastfeeding practices. First-time mothers also cited experiencing tension when there were differences in advice they received from different people.Conclusion: Overall, the mothers were well-informed on the benefits of breastfeeding, and displayed positive attitudes towards it. Nevertheless, few maintained optimal breastfeeding practices in the first two years of the infant's life. Further effort needs to be directed at addressing knowledge and non-knowledge barriers to optimal breastfeeding practices. Of particular importance is working with employers, developing supportive employment policies, providing postnatal support and working with lay people and health professionals. Research is also needed to identify the optimal combination of interventions to promote good breastfeeding practices. [ABSTRACT FROM AUTHOR]

Mangrove ecosystems are highly productive and provide important ecosystem services. However, in the Red Sea mangroves are under severe nutrient-limiting conditions, reflected in dwarf plants. The nutrient limitation is especially acute for iron, as verified experimentally, although the low carbon-to-nutrient stoichiometric ratios reported for Red Sea mangrove leaves are indicative of general nutrient depletion. Therefore, atmospheric nitrogen (N 2) fixation in mangrove sediments might be particularly important considering the minimal nitrogen inputs from land. Here, we tested the effect of temperature and crab density on sediment N 2 fixation rates in mature and juvenile mangrove (Avicennia marina) stands in the central Red Sea. The average N 2 fixation rates (from 0.002 ± 0.002 to 0.46 ± 0.12 mg N m−2 d−1) fall in the low range of N 2 fixation rates reported in mangroves elsewhere, which is in agreement with the small size of the mangrove plants. Mature mangrove sediments hold higher N 2 fixation rates than the juvenile mangrove sediment, related to a higher sediment organic matter and carbon content. We found a detrimental effect of temperature and crab density on sediment N 2 fixation rates. Maximum N 2 fixation rates were detected at 28 °C with a sharp decrease at 35 °C. Similarly, high crab-density reduced N 2 fixation, likely due to the sediment oxygenation or the grazing of cyanobacteria by crabs. This is supported by i) previously reported higher oxygen concentration and redox around burrows compared to undisturbed sediment and ii) lighter sediment carbon isotopic composition in high crab-density than in low crab-density sediments, indicating a higher contribution of microphytobenthos in the mature sediments supporting low crab-density. Our data document temperature and crab density as factors affecting N 2 fixation in the Red Sea mangrove sediments. • Sediment N2 fixation in Central Red Sea mangroves fall in the low range. • Higher N2 fixation rates in mature than juvenile mangrove sediments. • Temperature and crab density are important interacting drivers of N2 fixation. • Temperature and crab density had detrimental effects on mangrove N2 fixation. • High crab-density reduced N2 fixation, likely due to grazing of cyanobacteria. [ABSTRACT FROM AUTHOR]

In intertidal systems, the type and role of interactions among sediment microorganisms, animals, plants and abiotic factors are complex and not well understood. Such interactions are known to promote nutrient provision and cycling, and their dynamics and relationships may be of particular importance in arid microtidal systems characterized by minimal nutrient input. Focusing on an arid mangrove ecosystem on the central Red Sea coast, we investigated the effect of crab bioturbation intensity (comparing natural and manipulated high levels of bioturbation intensity) on biogeochemistry and bacterial communities of mangrove sediments, and on growth performance of Avicennia marina , over a period of 16 months. Along with pronounced seasonal patterns with harsh summer conditions, in which high sediment salinity, sulfate and temperature, and absence of tidal flooding occur, sediment bacterial diversity and composition, sediment physicochemical conditions, and plant performance were significantly affected by crab bioturbation intensity. For instance, bioturbation intensity influenced components of nitrogen, carbon, and phosphate cycling, bacterial relative abundance (i.e., Bacteroidia, Proteobacteria and Rhodothermi ) and their predicted functionality (i.e., chemoheterotrophy), likely resulting from enhanced metabolic activity of aerobic bacteria. The complex interactions among bacteria, animals, and sediment chemistry in this arid mangrove positively impact plant growth. We show that a comprehensive approach targeting multiple biological levels provides useful information on the ecological status of mangrove forests. IMPORTANCE Bioturbation is one of the most important processes that governs sediment biocenosis in intertidal systems. By facilitating oxygen penetration into anoxic layers, bioturbation alters the overall sediment biogeochemistry. Here, we investigate how high crab bioturbation intensity modifies the mangrove sediment bacterial community, which is the second largest component of mangrove sediment biomass and plays a significant role in major biogeochemical processes. We show that the increase in crab bioturbation intensity, by ameliorating the anoxic condition of mangrove sediment and promoting sediment bacterial diversity in favor of a beneficial bacterial microbiome, improves mangrove tree growth in arid environments. These findings have significant implications because they show how crabs, by farming the mangrove sediment, can enhance the overall capacity of the system to sustain mangrove growth, fighting climate change.

Background: The benefits of breastfeeding are well-recognised. The majority of first-time mothers in the Lao People's Democratic Republic however do not follow WHO guidelines of exclusively breastfeeding for the first six months, and less than half breastfeed for two years. UNICEF identified lack of exclusive breastfeeding as the second highest risk factor for under 5 mortality in Lao PDR, closely following lack of skilled delivery care. This study explored the reasons and influences behind first-time mothers' breastfeeding practices, as well as the role of attitudes, beliefs and experiences in influencing those practices., Methods: A qualitative research design was chosen for this exploratory study. Two districts in Vientiane were selected, and in each district four focus group discussions, two with six first-time mothers and two with health staff were undertaken. In addition, sixteen in-depth interviews with first-time mothers and seven individual key informants were conducted., Results: Participants demonstrated positive attitudes towards breastfeeding and recognised its importance. Despite this, breastfeeding practices were suboptimal. Few exclusively breastfed for the first six months of the baby's life and most of the first-time mothers included in the sample had stopped or planned to stop breastfeeding by the time the infant was 18 months of age. Work was named as one of the main reasons for less than ideal breastfeeding practices. Traditional beliefs and advice from health staff and the first-time mothers' own mothers, were important influences on breastfeeding practices. First-time mothers also cited experiencing tension when there were differences in advice they received from different people., Conclusion: Overall, the mothers were well-informed on the benefits of breastfeeding, and displayed positive attitudes towards it. Nevertheless, few maintained optimal breastfeeding practices in the first two years of the infant's life. Further effort needs to be directed at addressing knowledge and non-knowledge barriers to optimal breastfeeding practices. Of particular importance is working with employers, developing supportive employment policies, providing postnatal support and working with lay people and health professionals. Research is also needed to identify the optimal combination of interventions to promote good breastfeeding practices.