227 research outputs found
Effect of Silene vulgaris and Heavy Metal Pollution on Soil; Microbial Diversity in Long-Term Contaminated Soil
In this study, we analysed the impact of heavy metals and plant rhizodeposition on the structure of indigenous microbial communities in rhizosphere and bulk soil that had been exposed to heavy metals for more than 150 years. Samples of the rhizosphere of Silene vulgaris and non-rhizosphere soils 250 and 450 m from the source of emission that had different metal concentrations were collected for analyses. The results showed that soils were collected 250 m from the smelter had a higher number of Cd-resistant CFU compared with the samples that were collected from 450 m, but no significant differences were observed in the number of total and oligotrophic CFU or the equivalent cell numbers between rhizosphere and non-rhizosphere soils that were taken 250 and 450 m from the emitter. Unweighted pair group method with arithmetic mean (UPGMA) cluster analysis of the denaturing gradient gel electrophoresis (DGGE) profiles, as well as a cluster analysis that was generated on the phospholipid fatty acid (PLFA) profiles, showed that the bacterial community structure of rhizosphere soils depended more on the plant than on the distance and metal concentrations. The sequencing of the 16S rDNA fragments that were excised from the DGGE gel revealed representatives of the phyla Bacteroidetes, Acidobacteria, Gemmatimonadetes, Actinobacteria and Betaproteobacteria in the analysed soil with a predominance of the first three groups. The obtained results demonstrated that the presence of S. vulgaris did not affect the number of CFUs, except for those of Cd-resistant bacteria. However, the presence of S. vulgaris altered the soil bacterial community structure, regardless of the sampling site, which supported the thesis that plants have a higher impact on soil microbial community than metal contamination.Peer reviewe
Indoor green wall affects health-associated commensal skin microbiota and enhances immune regulation : A randomized trial among urban office workers
Urbanization reduces microbiological abundance and diversity, which has been associated with immune mediated diseases. Urban greening may be used as a prophylactic method to restore microbiological diversity in cities and among urbanites. This study evaluated the impact of air-circulating green walls on bacterial abundance and diversity on human skin, and on immune responses determined by blood cytokine measurements. Human subjects working in offices in two Finnish cities (Lahti and Tampere) participated in a two-week intervention, where green walls were installed in the rooms of the experimental group. Control group worked without green walls. Skin and blood samples were collected before (Day0), during (Day14) and two weeks after (Day28) the intervention. The relative abundance of genus Lactobacillus and the Shannon diversity of phylum Proteobacteria and class Gammaproteobacteria increased in the experimental group. Proteobacterial diversity was connected to the lower proinflammatory cytokine IL-17A level among participants in Lahti. In addition, the change in TGF-beta 1 levels was opposite between the experimental and control group. As skin Lactobacillus and the diversity of Proteobacteria and Gammaproteobacteria are considered advantageous for skin health, air-circulating green walls may induce beneficial changes in a human microbiome. The immunomodulatory potential of air-circulating green walls deserves further research attention.Peer reviewe
Infinite factorization of multiple non-parametric views
Combined analysis of multiple data sources has increasing application interest, in particular for distinguishing shared and source-specific aspects. We extend this rationale of classical canonical correlation analysis into a flexible, generative and non-parametric clustering
setting, by introducing a novel non-parametric hierarchical
mixture model. The lower level of the model describes each source with a flexible non-parametric mixture, and the top level combines these to describe commonalities of the sources. The lower-level clusters arise from hierarchical Dirichlet Processes, inducing an infinite-dimensional contingency table between the views. The commonalities between the sources are modeled by an infinite block
model of the contingency table, interpretable as non-negative factorization of infinite matrices, or as a prior for infinite contingency tables. With Gaussian mixture components plugged in for continuous measurements, the model is applied to two views of genes, mRNA expression and abundance of the produced proteins, to expose groups of genes that are co-regulated in either or both of the views.
Cluster analysis of co-expression is a standard simple way of screening for co-regulation, and the two-view analysis extends the approach to distinguishing between pre- and post-translational regulation
Halogenated organic compounds in archived whale oil : a pre-industrial record
Author Posting. © The Authors, 2006. This is the author's version of the work. It is posted here by permission of Elsevier B.V. for personal use, not for redistribution. The definitive version was published in Environmental Pollution 145 (2007): 668-671, doi:10.1016/j.envpol.2006.08.022.To provide additional evidence that several halogenated organic compounds (HOCs) found in environmental samples are natural and not industrially produced, we analyzed an archived whale oil sample collected in 1921 from the last voyage of the whaling ship Charles W. Morgan. This sample, which predates large-scale industrial manufacture of HOCs, contained two methoxylated polybrominated diphenyl ethers (MeO-PBDEs), five halogenated methyl bipyrroles (MBPs), one halogenated dimethyl bipyrrole (DMBP), and one dimethoxylated polybrominated biphenyl (diMeO-PBB). This result indicates, at least in part, a natural source of the latter compounds. Capsule Nine halogenated organic compounds have been detected in archived whale oil from the 1920s.This work was supported by the National Science Foundation (OCE-0221181 and OCE-0550486), the Woods Hole Oceanographic Institution (WHOI) Ocean Life Institute and the Postdoctoral Scholar Program at WHOI (with funding from The Camille and Henry Dreyfus Foundation, Inc. and The J. Seward Johnson Fund)
Ellagitannins Inhibit the Exsheathment of Haemonchus contortus and Trichostrongylus colubriformis Larvae: The Efficiency Increases Together with the Molecular Size
Worldwide, parasitic gastrointestinal nematodes continue to threaten animal health, welfare, and production in outdoor breeding systems of small ruminants. For more than 50 years, the control of these parasitic worms has relied on the use of commercial synthetic anthelmintics. However, anthelmintic resistance in worm populations is nowadays widespread and requires novel solutions. The use of tannin-rich plants has been suggested as an alternative to synthetic anthelmintics to control gastrointestinal nematodes. The majority of previous studies have focused on the activity of proanthocyanidins (syn condensed tannins), and less is known about ellagitannins. In this study, the effects of 30 structurally unique ellagitannins on the exsheathment of third-stage infective larvae were examined on Haemonchus contortus and Trichostrongylus colubriformis by the in vitro larval exsheathment inhibition assay. Ellagitannins were found to be promising natural anthelmintics as they showed direct inhibition on larval exsheathment for both nematode species. In general, ellagitannins were more efficient at inhibiting the exsheathment of H. contortus larvae than those of T. colubriformis. The efficiency of inhibition increased as the degree of oligomerization or the molecular weight of the ellagitannin increased. Otherwise, we found no other structural features of ellagitannins that significantly affected the anthelmintic activity on the third-stage infective larvae. The effective concentrations were physiologically relevant and should be achievable in the gastrointestinal tract also in in vivo conditions
Successful aerobic bioremediation of groundwater contaminated with higher chlorinated phenols by indigenous degrader bacteria
© 2018 Elsevier Ltd The xenobiotic priority pollutant pentachlorophenol has been used as a timber preservative in a polychlorophenol bulk synthesis product containing also tetrachlorophenol and trichlorophenol. Highly soluble chlorophenol salts have leaked into groundwater, causing severe contamination of large aquifers. Natural attenuation of higher-chlorinated phenols (HCPs: pentachlorophenol + tetrachlorophenol) at historically polluted sites has been inefficient, but a 4-year full scale in situ biostimulation of a chlorophenol-contaminated aquifer by circulation and re-infiltration of aerated groundwater was remarkably successful: pentachlorophenol decreased from 400 μg L−1 to <1 μg L−1 and tetrachlorophenols from 4000 μg L−1 to <10 μg L−1. The pcpB gene, the gene encoding pentachlorophenol hydroxylase - the first and rate-limiting enzyme in the only fully characterised aerobic HCP degradation pathway - was present in up to 10% of the indigenous bacteria already 4 months after the start of aeration. The novel quantitative PCR assay detected the pcpB gene in situ also in the chlorophenol plume of another historically polluted aquifer with no remediation history. Hotspot groundwater HCPs from this site were degraded efficiently during a 3-week microcosm incubation with one-time aeration but no other additives: from 5400 μg L−1 to 1200 μg L−1 and to 200 μg L−1 in lightly and fully aerated microcosms, respectively, coupled with up to 2400% enrichment of the pcpB gene. Accumulation of lower-chlorinated metabolites was observed in neither in situ remediation nor microcosms, supporting the assumption that HCP removal was due to the aerobic degradation pathway where the first step limits the mineralisation rate. Our results demonstrate that bacteria capable of aerobic mineralisation of xenobiotic pentachlorophenol and tetrachlorophenol can be present at long-term polluted groundwater sites, making bioremediation by simple aeration a viable and economically attractive alternative
Dicer Is Associated with Ribosomal DNA Chromatin in Mammalian Cells
Background: RNA silencing is a common term for pathways utilizing small RNAs as sequence-specific guides to repress gene expression. Components of the RNA silencing machinery are involved in different aspects of chromatin function in numerous organisms. However, association of RNA silencing with chromatin in mammalian cells remains unclear. Methodology/Principal Findings: Immunostaining of mitotic chromosomes with antibodies visualizing either endogenous or ectopically expressed Dicer in mammalian cells revealed association of the protein with ribosomal DNA (rDNA) repeats. Chromatin immunoprecipitations and bisulfite sequencing experiments indicated that Dicer is associated with transcribed regions of both active and silenced genes in rDNA arrays of interphase chromosomes. Metabolic labeling of the mouse embryonic stem (ES) cells lacking Dicer did not reveal apparent defect in rRNA biogenesis though pre-rRNA synthesis in these cells was decreased, likely as a consequence of their slower growth caused by the loss of miRNAs. We analyzed in detail chromatin structure of rDNA but did not find any epigenetic changes at rDNA loci in Dicer 2/2 ES cells. Instead, we found that rDNA methylation is rather low in primary tissues, contrasting with rDNA methylation patterns in transformed cell lines. Conclusion/Significance: We found that Dicer, a key component of RNA silencing pathways, can be detected in association with rDNA chromatin in mammalian cells. The role of this particular localization of Dicer is not readily apparent since th
Visual ecology of aphids – a critical review on the role of colours in host finding
We review the rich literature on behavioural responses of aphids (Hemiptera: Aphididae) to stimuli of different colours. Only in one species there are adequate physiological data on spectral sensitivity to explain behaviour crisply in mechanistic terms.
Because of the great interest in aphid responses to coloured targets from an evolutionary, ecological and applied perspective, there is a substantial need to expand these studies to more species of aphids, and to quantify spectral properties of stimuli rigorously. We show that aphid responses to colours, at least for some species, are likely based on a specific colour opponency mechanism, with positive input from the green domain of the spectrum and negative input from the blue and/or UV region.
We further demonstrate that the usual yellow preference of aphids encountered in field experiments is not a true colour preference but involves additional brightness effects. We discuss the implications for agriculture and sensory ecology, with special respect to the recent debate on autumn leaf colouration. We illustrate that recent evolutionary theories concerning aphid–tree interactions imply far-reaching assumptions on aphid responses to colours
that are not likely to hold. Finally we also discuss the
implications for developing and optimising strategies
of aphid control and monitoring
Eighth Annual Conference of inVIVO Planetary Health: From Challenges to Opportunities
inVIVO Planetary Health (inVIVO) is a progressive scientific movement providing evidence, advocacy, and inspiration to align the interests and vitality of people, place, and planet. Our goal is to transform personal and planetary health through awareness, attitudes, and actions, and a deeper understanding of how all systems are interconnected and interdependent. Here, we present the abstracts and proceedings of our 8th annual conference, held in Detroit, Michigan in May 2019, themed “From Challenges, to Opportunities”. Our far-ranging discussions addressed the complex interdependent ecological challenges of advancing global urbanization, including the biopsychosocial interactions in our living environment on physical, mental, and spiritual wellbeing, together with the wider community and societal factors that govern these. We had a strong solutions focus, with diverse strategies spanning from urban-greening and renewal, nature-relatedness, nutritional ecology, planetary diets, and microbiome rewilding, through to initiatives for promoting resilience, positive emotional assets, traditional cultural narratives, creativity, art projects for personal and community health, and exploring ways of positively shifting mindsets and value systems. Our cross-sectoral agenda underscored the importance and global impact of local initiatives everywhere by contributing to new normative values as part of a global interconnected grass-roots movement for planetary health
Mediation and the Best Interests of the Child from the Child Law Perspective
What is the best interests of the child in family mediation and is mediation in the best interests of the child? In this article, I use child law and the United Nations Convention on the Rights of the Child combined with mediation theory to discuss these questions. Both mediation and the best interests of the child are open for multiple interpretations. Using facilitative and evaluative mediation theory and the legal concept ‘the best interests of the child’, I explore and compare the understandings of these concepts as they apply to family mediation. This includes a discussion of the advantages and disadvantages of facilitative as well as evaluative mediation orientations in terms of protecting the best interests of the child. Finnish court-connected family mediation is a combination of both mediation orientations, and the mediator is obliged to secure the best interests of the child. From a theoretical point of view, this seems to be a challenging combination.Peer reviewe
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