157 research outputs found
Tobacco Smoking And The Resting Maternal Brain: A Preliminary Study Of Frontal EEG
Tobacco smoking has been attributed to a wide range of detrimental health consequences for both women and their children. In addition to its known physical health effects, smoking may also impact maternal neural responses and subsequent caregiving behavior. To begin investigating this issue, we employed electroencephalography (EEG) to examine resting neural oscillations of tobacco-smoking mothers (n = 35) and non-smoking mothers (n = 35). We examined seven EEG frequency bands recorded from frontal electrode sites (delta, theta, alpha, alpha1, alpha2, beta, and gamma). While no between-group differences were present in high-frequency bands (alpha2, beta, gamma), smokers showed greater spectral power in low-frequency bands (delta, theta, alpha, alpha1) compared to non-smokers. This increased power in low-frequency bands of tobacco-smoking mothers is consistent with a less aroused state and may be one mechanism through which smoking might affect the maternal brain and caregiving behavior
No apparent costs for facultative antibiotic production by the soil bacterium Pseudomonas fluorescens Pf0-1
This is the final version of the article. Available on open access from the publisher via the DOI in this record.BACKGROUND: Many soil-inhabiting bacteria are known to produce secondary metabolites that can suppress microorganisms competing for the same resources. The production of antimicrobial compounds is expected to incur fitness costs for the producing bacteria. Such costs form the basis for models on the co-existence of antibiotic-producing and non-antibiotic producing strains. However, so far studies quantifying the costs of antibiotic production by bacteria are scarce. The current study reports on possible costs, for antibiotic production by Pseudomonas fluorescens Pf0-1, a soil bacterium that is induced to produce a broad-spectrum antibiotic when it is confronted with non-related bacterial competitors or supernatants of their cultures. METHODOLOGY AND PRINCIPAL FINDINGS: We measured the possible cost of antibiotic production for Pseudomonas fluorescens Pf0-1 by monitoring changes in growth rate with and without induction of antibiotic production by supernatant of a bacterial competitor, namely Pedobacter sp.. Experiments were performed in liquid as well as on semi-solid media under nutrient-limited conditions that are expected to most clearly reveal fitness costs. Our results did not reveal any significant costs for production of antibiotics by Pseudomonas fluorescens Pf0-1. Comparison of growth rates of the antibiotic-producing wild-type cells with those of non-antibiotic producing mutants did not reveal costs of antibiotic production either. SIGNIFICANCE: Based on our findings we propose that the facultative production of antibiotics might not be selected to mitigate metabolic costs, but instead might be advantageous because it limits the risk of competitors evolving resistance, or even the risk of competitors feeding on the compounds produced.This work is financed by The Netherlands Organization for Scientific Research. The funders had no role in study design, data collection and analysis,
decision to publish, or preparation of the manuscript
The role of agri-environment schemes in conservation and environmental management.
Over half of the European landscape is under agricultural management and has been for millennia. Many species and ecosystems of conservation concern in Europe depend on agricultural management and are showing ongoing declines. Agri-environment schemes (AES) are designed partly to address this. They are a major source of nature conservation funding within the European Union (EU) and the highest conservation expenditure in Europe. We reviewed the structure of current AES across Europe. Since a 2003 review questioned the overall effectiveness of AES for biodiversity, there has been a plethora of case studies and meta-analyses examining their effectiveness. Most syntheses demonstrate general increases in farmland biodiversity in response to AES, with the size of the effect depending on the structure and management of the surrounding landscape. This is important in the light of successive EU enlargement and ongoing reforms of AES. We examined the change in effect size over time by merging the data sets of 3 recent meta-analyses and found that schemes implemented after revision of the EU's agri-environmental programs in 2007 were not more effective than schemes implemented before revision. Furthermore, schemes aimed at areas out of production (such as field margins and hedgerows) are more effective at enhancing species richness than those aimed at productive areas (such as arable crops or grasslands). Outstanding research questions include whether AES enhance ecosystem services, whether they are more effective in agriculturally marginal areas than in intensively farmed areas, whether they are more or less cost-effective for farmland biodiversity than protected areas, and how much their effectiveness is influenced by farmer training and advice? The general lesson from the European experience is that AES can be effective for conserving wildlife on farmland, but they are expensive and need to be carefully designed and targeted.This is the final published version. It first appeared from Wiley http://dx.doi.org/10.1111/cobi.1253
Nature Balance 2002
To reach a National Ecological Network (NEN), further efforts in spatial planning of the green space are necessary. This is the main outcome of Nature Balance 2002. Nature has high social and economical values. According to the inhabitants of The Netherlands, nature areas and variation in landscape contribute significantly to their well-being. Nature and landscape also have ion and increases prices of housings in green areas. Evidence grows that green surroundings benefit people?s health. The European Union has composed a list of international protected plants and animal species. The Netherlands has accepted these duties as established in the Birds and Habitats Directives. More insight in the occurrence of these species in specific habitats is needed. This may increase public acceptance and implementation of species protection policies. In order to meet nature targets, spatial planning of the green environment is a necessity. Only in this way the coherent National Ecological Network can be realized. Offers of land to be incorporated in the NEN have increased during the last three years. The Dutch Government plans to halve the budget for acquiring land and instead have private land owners participate in nature management. Signing long-term contracts with these private owners can contribute to the nature goals, but is hardly less expensive than buying the land. Also more spatial protection of the NEN will be needed when less land for nature development is purchased.Om de Ecologische Hoofdstructuur te realiseren is verdere ordening van de groene ruimte noodzakelijk. Dat is de hoofdconclusie uit de Natuurbalans 2002. Natuur heeft grote sociale en economische betekenis. De inwoners van Nederland vinden dat natuurgebieden en gevarieerde landschappen een wezenlijke bijdrage leveren aan hun welzijn. Daarnaast hebben natuur en landschap een substantikle economische waarde, onder andere vanwege de inkomsten uit recreatie in natuurgebieden en de bereidheid van kopers om meer te betalen voor een huis in een groen gebied. Er zijn bovendien steeds meer gegevens die er op wijzen dat de gezondheid van mensen baat heeft bij een groene omgeving. Op Europees niveau is een lijst van internationaal te beschermen planten- en diersoorten samengesteld. Nederland is hiervoor verplichtingen aangegaan die zijn vastgelegd in de Vogelrichtlijn en Habitatrichtlijn van de Europese Unie. Om het maatschappelijke draagvlak voor dit soortenbeleid te vergroten en het beleid hanteerbaar te maken moet meer zicht komen op het verband tussen het voorkomen van individuen en populaties van soorten en de ligging van hun leefgebieden. Voor het bereiken van de natuurdoelen is ordening van de groene ruimte nodig om het beoogde samenhangende netwerk van natuurgebieden, de Ecologische Hoofdstructuur (EHS) te realiseren. Het aanbod van aan te kopen grond voor de realisatie van de EHS neemt de laatste drie jaar toe. De nieuwe regering heeft het voornemen het jaarlijkse budget voor de aankoop van grond te halveren en meer particuliere eigenaren in te zetten bij het ontwikkelen en beheren van natuur. Langjarige contracten met deze particulieren kunnen een bijdrage aan de natuurdoelen leveren, maar blijken nauwelijks goedkoper dan aankoop. Ook vergt een samenhangende EHS, indien minder grond voor natuurontwikkeling wordt opgekocht, een goede ruimtelijke bescherming
Selection for antimicrobial resistance is reduced when embedded in a natural microbial community
This is the final version. Available from Springer Nature via the DOI in this record.Antibiotic resistance has emerged as one of the most pressing, global threats to public health. In single-species experiments selection for antibiotic resistance occurs at very low antibiotic concentrations. However, it is unclear how far these findings can be extrapolated to natural environments, where species are embedded within complex communities. We competed isogenic strains of Escherichia coli, differing exclusively in a single chromosomal resistance determinant, in the presence and absence of a pig faecal microbial community across a gradient of antibiotic concentration for two relevant antibiotics: gentamicin and kanamycin. We show that the minimal selective concentration was increased by more than one order of magnitude for both antibiotics when embedded in the community. We identified two general mechanisms were responsible for the increase in minimal selective concentration: an increase in the cost of resistance and a protective effect of the community for the susceptible phenotype. These findings have implications for our understanding of the evolution and selection of antibiotic resistance, and can inform future risk assessment efforts on antibiotic concentrations.Medical Research Council (MRC)European Commissio
Microbiology of the phyllosphere: a playground for testing ecological concepts
Many concepts and theories in ecology are highly debated, because it is often difficult to design decisive tests with sufficient replicates. Examples include biodiversity theories, succession concepts, invasion theories, coexistence theories, and concepts of life history strategies. Microbiological tests of ecological concepts are rapidly accumulating, but have yet to tap into their full potential to complement traditional macroecological theories. Taking the example of microbial communities on leaf surfaces (i.e. the phyllosphere), we show that most explorations of ecological concepts in this field of microbiology focus on autecology and population ecology, while community ecology remains understudied. Notable exceptions are first tests of the island biogeography theory and of biodiversity theories. Here, the phyllosphere provides the unique opportunity to set up replicated experiments, potentially moving fields such as biogeography, macroecology, and landscape ecology beyond theoretical and observational evidence. Future approaches should take advantage of the great range of spatial scales offered by the leaf surface by iteratively linking laboratory experiments with spatial simulation models
Quantifying the effectiveness of climate change mitigation through forest plantations and carbon sequestration with an integrated land-use model
<p>Abstract</p> <p>Background</p> <p>Carbon plantations are introduced in climate change policy as an option to slow the build-up of atmospheric carbon dioxide (CO<sub>2</sub>) concentrations. Here we present a methodology to evaluate the potential effectiveness of carbon plantations. The methodology explicitly considers future long-term land-use change around the world and all relevant carbon (C) fluxes, including all natural fluxes. Both issues have generally been ignored in earlier studies.</p> <p>Results</p> <p>Two different baseline scenarios up to 2100 indicate that uncertainties in future land-use change lead to a near 100% difference in estimates of carbon sequestration potentials. Moreover, social, economic and institutional barriers preventing carbon plantations in natural vegetation areas decrease the physical potential by 75–80% or more.</p> <p>Nevertheless, carbon plantations can still considerably contribute to slowing the increase in the atmospheric CO<sub>2 </sub>concentration but only in the long term. The most conservative set of assumptions lowers the increase of the atmospheric CO<sub>2 </sub>concentration in 2100 by a 27 ppm and compensates for 5–7% of the total energy-related CO<sub>2 </sub>emissions. The net sequestration up to 2020 is limited, given the short-term increased need for agricultural land in most regions and the long period needed to compensate for emissions through the establishment of the plantations. The potential is highest in the tropics, despite projections that most of the agricultural expansion will be in these regions. Plantations in high latitudes as Northern Europe and Northern Russia should only be established if the objective to sequester carbon is combined with other activities.</p> <p>Conclusion</p> <p>Carbon sequestration in plantations can play an important role in mitigating the build-up of atmospheric CO<sub>2</sub>. The actual magnitude depends on natural and management factors, social barriers, and the time frame considered. In addition, there are a number of ancillary benefits for local communities and the environment. Carbon plantations are, however, particularly effective in the long term. Furthermore, plantations do not offer the ultimate solution towards stabilizing CO<sub>2 </sub>concentrations but should be part of a broader package of options with clear energy emission reduction measures.</p
Openness in participation, assessment, and policy making upon issues of environment and environmental health: a review of literature and recent project results
Issues of environment and environmental health involve multiple interests regarding e.g. political, societal, economical, and public concerns represented by different kinds of organizations and individuals. Not surprisingly, stakeholder and public participation has become a major issue in environmental and environmental health policy and assessment. The need for participation has been discussed and reasoned by many, including environmental legislators around the world. In principle, participation is generally considered as desirable and the focus of most scholars and practitioners is on carrying out participation, and making participation more effective. In practice also doubts regarding the effectiveness and importance of participation exist among policy makers, assessors, and public, leading even to undermining participatory practices in policy making and assessment
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