End-Member Modeling Analyses (EMMA) of pseudo-Thellier style experiments to derive absolute paleointensities from lavas

Over the past years several groups have made efforts to calibrate the ‘pseudo-Thellier’ technique to obtain paleointensities from materials that acquired their natural remanent magnetizations thermally, while avoiding heating the samples during the experiments. These calibrations revolve around mapping laboratory induced Anhysteretic Remanent Magnetizations (ARMs) to thermally acquired Natural Remanent Magnetizations (NRMs). One approach has been to plot pseudo-Thellier slopes against paleointensities that are either known (for very young lavas) or result from different paleointensity techniques. Although the obtained calibration relation is linear and closely follows the data, the relation worryingly misses th

An end-member modeling approach (EMMA) to pseudo-Thellier paleointensity data

Absolute paleointensities are notoriously hard to obtain, because conventional thermal Thellier paleointensity experiments often have low success rates for volcanic samples. The thermal treatments necessary for these experiments potentially induce (magnetic) alteration in the samples, preventing a reliable paleointensity estimate. These heating steps can be avoided by pseudo-Thellier measurements, where samples are demagnetized and remagnetized with alternating-fields. However, pseudo-Thellier experiments intrinsically produce relative paleointensities. Over the past years attempts were made to calibrate pseudo-Thellier results into absolute paleointensities for lavas by mapping laboratory induced Anhysteretic Remanent Magnetizations (ARMs) to the thermally acquired Natural Remanent Magnetizations (NRMs). Naturally occurring volcanic rocks, however, are assemblages of minerals differing in grain size, shape, and chemistry. These different minerals all have their own characteristic mapping between ARMs and thermal NRMs Here we show that it is possible to find these characteristic mappings by unmixing the NRM demagnetization and the ARM acquisition curves into end-members, with an iterative method of non-negative matrix factorization. In turn, this end-member modeling approach (EMMA) allows for the calculation of absolute paleointensities from pseudo-Thellier measurements. We tested our end-member modeling approach using a noise-free numerical data set, yielding a perfect reconstruction of the paleointensities. When adding noise up to levels beyond what is expected in natural samples, the end-member model still produces the known paleointensities well. In addition, we made a synthetic dataset with natural volcanic samples from different volcanic edifices that were given a magnetization by heating and cooling them in a controlled magnetic field in the lab. The applied fields ranged between 10 and 70 μT⁠. The average absolute difference between the calculated paleointensity and the known lab-field is around 10 μT for the models with 2 to 4 end-members, while the paleointensity of almost all flows can be retrieved within a deviation of ± 20 μT⁠. The average difference between calculated paleointensities for the 3 end-member model is -1.7 μT⁠. The deviations between the paleointensities and the known lab-fields are almost Gaussian distributed around the expected values. To assess whether the end-members produced by our analysis have a physical meaning, we measured the Curie temperatures of our samples. These Curie measurements show that there is a relationship between the abundances of the end members of the 3 end-member model in the samples and their dominant Curie temperatures. This indicates that even whilst the spectrum of Curie temperatures and hence composition of iron-oxides in the sample set is continuous, and the magnetization is also related to mineral size and shape, the calculated end-members of the 3 end-member model are somewhat related to magnetic mineral composition present in the samples. Although the two datasets in our study show that there is potential for using this end-member modeling technique for finding absolute paleointensities from pseudo-Thellier data, these synthetic datasets cannot be directly related to natural samples. Therefore, it is necessary to compile a dataset of known paleointensities from different volcanic sites that recently cooled in a known magnetic field to find the universal end-members in future studies

The Association of Computed Tomography-Assessed Body Composition with Mortality in Patients with Necrotizing Pancreatitis

Background: Identification of patients with necrotizing pancreatitis at high risk for a complicated course could facilitate clinical decision-making. In multiple diseases, several parameters of body composition are associated with impaired outcome, but studies in necrotizing pancreatitis are lacking. Methods: A post hoc analysis was performed in a national prospective cohort of 639 patients with necrotizing pancreatitis. Skeletal muscle mass, skeletal muscle density, and visceral adipose tissue were measured at the third lumbar vertebra level (L3) on contrast-enhanced computed tomography (CT) within 10 days after initial admission and 1 month thereafter. Results: In total, 496 of 639 patients (78%) were included. Overall mortality rate was 14.5%. Skeletal muscle mass and density and visceral adipose tissue on first CT were not independently associated with in-hospital mortality. However, low skeletal muscle density was independently associated with increased mortality in patients ≥65 years (OR 2.54 (95%CI 1.12–5.84, P = 0.028). Skeletal muscle mass and density significantly decreased within 1 month, for both males and females, with a median relative loss of muscle mass of 12.9 and 10.2% (both P < 0.001), respectively. Skeletal muscle density decreased with 7.2 and 7.5% (both P < 0.001) for males and females, respectively. A skeletal muscle density decrease of ≥10% in 1 month was independently associated with in-hospital mortality: OR 5.87 (95%CI 2.09–16.50, P = 0.001). Conclusion: First CT-assessed body composition parameters do not correlate with in-hospital mortality in patients with necrotizing pancreatitis. Loss of skeletal muscle density ≥10% within the first month after initial admission, however, is significantly associated with increased mortality in these patients

Offspring outcomes after prenatal interventions for common mental disorders:a meta-analysis

Background: It is presumed that pharmacological and non-pharmacological treatment of prenatal common mental disorders can mitigate associated adverse effects in offspring, yet strong evidence for the prophylactic benefits of treatment is lacking. We therefore examined the effect of prenatal treatments for common mental disorders on offspring outcomes. Methods: For this meta-analysis, articles published up to August 31, 2017, were obtained from PubMed, PsycInfo, Embase, and Cochrane databases. Included studies needed to be randomized controlled trials (RCTs) on the effect of treatment of prenatal common mental disorders comparing an intervention to a control condition, including offspring outcome(s). Random effects models were used to calculate Hedges' g in the program Comprehensive Meta-Analysi

Ovalbumin-Induced Epithelial Activation Directs Monocyte-Derived Dendritic Cells to Instruct Type 2 Inflammation in T Cells Which Is Differentially Modulated by 2'-Fucosyllactose and 3-Fucosyllactose

Allergic sensitization starts with epithelial cell activation driving dendritic cells (DCs) to instruct T helper 2 (Th2) cell polarization. Food allergens trigger intestinal epithelial cell (IEC) activation. Human milk oligosaccharides may temper the allergic phenotype by shaping mucosal immune responses.We investigated in vitro mucosal immune development after allergen exposure by combining ovalbumin (OVA)-preexposed IEC with monocyte-derived DCs (OVA-IEC-DCs) and subsequent coculture of OVA-IEC-DCs with Th cells. IECs were additionally preincubated with 2'FL or 3FL.OVA activation increased IEC cytokine secretion. OVA-IEC-DCs instructed both IL13 (p < 0.05) and IFNγ (p < 0.05) secretion from Th cells. 2'FL and 3FL permitted OVA-induced epithelial activation, but 2'FL-OVA-IEC-DCs boosted inflammatory and regulatory T-cell development. 3FL-OVA-IEC lowered IL12p70 and IL23 in DCs and suppressed IL13 (p < 0.005) in T cells, while enhancing IL17 (p < 0.001) and IL10 (p < 0.005).These results show that OVA drives Th2- and Th1-type immune responses via activation of IECs in this model. 2'FL and 3FL differentially affect OVA-IEC-driven immune effects. 2'FL boosted overall T-cell OVA-IEC immunity via DC enhancing inflammatory and regulatory responses. 3FL-OVA-IEC-DCs silenced IL13, shifting the balance towards IL17 and IL10.This model demonstrates the contribution of IEC to OVA Th2-type immunity. 2'FL and 3FL modulate the OVA-induced activation in this novel model to study allergic sensitization

Estimation of incidence and social cost of colon cancer due to nitrate in drinking water in the EU: a tentative cost-benefit assessment

<p>Abstract</p> <p>Background</p> <p>Presently, health costs associated with nitrate in drinking water are uncertain and not quantified. This limits proper evaluation of current policies and measures for solving or preventing nitrate pollution of drinking water resources. The cost for society associated with nitrate is also relevant for integrated assessment of EU nitrogen policies taking a perspective of welfare optimization. The overarching question is at which nitrogen mitigation level the social cost of measures, including their consequence for availability of food and energy, matches the social benefit of these measures for human health and biodiversity.</p> <p>Methods</p> <p>Epidemiological studies suggest colon cancer to be possibly associated with nitrate in drinking water. In this study risk increase for colon cancer is based on a case-control study for Iowa, which is extrapolated to assess the social cost for 11 EU member states by using data on cancer incidence, nitrogen leaching and drinking water supply in the EU. Health costs are provisionally compared with nitrate mitigation costs and social benefits of fertilizer use.</p> <p>Results</p> <p>For above median meat consumption the risk of colon cancer doubles when exposed to drinking water exceeding 25 mg/L of nitrate (NO₃) for more than ten years. We estimate the associated increase of incidence of colon cancer from nitrate contamination of groundwater based drinking water in EU11 at 3%. This corresponds to a population-averaged health loss of 2.9 euro per capita or 0.7 euro per kg of nitrate-N leaching from fertilizer.</p> <p>Conclusions</p> <p>Our cost estimates indicate that current measures to prevent exceedance of 50 mg/L NO₃are probably beneficial for society and that a stricter nitrate limit and additional measures may be justified. The present assessment of social cost is uncertain because it considers only one type of cancer, it is based on one epidemiological study in Iowa, and involves various assumptions regarding exposure. Our results highlight the need for improved epidemiological studies.</p

Nitrogen processes in aquatic ecosystems

Executive summary Nature of the problem (science/management/policy) • Freshwater ecosystems play a key role in the European nitrogen (N) cycle, both as a reactive agent that transfers, stores and processes N loadings from the atmosphere and terrestrial ecosystems, and as a natural environment severely impacted by the increase of these loadings. Approaches • This chapter is a review of major processes and factors controlling N transport and transformations for running waters, standing waters, groundwaters and riparian wetlands. Key findings/state of knowledge • The major factor controlling N processes in freshwater ecosystems is the residence time of water, which varies widely both in space and in time, and which is sensitive to changes in climate, land use and management. • The effects of increased N loadings to European freshwaters include acidification in semi-natural environments, and eutrophication in more disturbed ecosystems, with associated loss of biodiversity in both cases. • An important part of the nitrogen transferred by surface waters is in the form of organic N, as dissolved organic N (DON) and particulate organic N (PON). This part is dominant in semi-natural catchments throughout Europe and remains a significant component of the total N load even in nitrate enriched rivers. • In eutrophicated standing freshwaters N can be a factor limiting or co-limiting biological production, and control of both N and phosphorus (P) loading is oft en needed in impacted areas, if ecological quality is to be restored. Major uncertainties/challenges • The importance of storage and denitrifi cation in aquifers is a major uncertainty in the global N cycle, and controls in part the response of catchments to land use or management changes. In some aquifers, the increase of N concentrations will continue for decades even if efficient mitigation measures are implemented now. • Nitrate retention by riparian wetlands has oft en been highlighted. However, their use for mitigation must be treated with caution, since their effectiveness is difficult to predict, and side effects include increased DON emissions to adjacent open waters, N2O emissions to the atmosphere, and loss of biodiversity. • In fact, the character and specific spatial origins of DON are not fully understood, and similarly the quantitative importance of indirect N2O emissions from freshwater ecosystems as a result of N leaching losses from agricultural soils is still poorly known at the regional scale. • These major uncertainties remain due to the lack of adequate monitoring (all forms of N at a relevant frequency), especially – but not only – in the southern and eastern EU countries. Recommendations (research/policy) • The great variability of transfer pathways, buffering capacity and sensitivity of the catchments and of the freshwater ecosystems calls for site specific mitigation measures rather than standard ones applied at regional to national scale. • The spatial and temporal variations of the N forms, the processes controlling the transport and transformation of N within freshwaters, require further investigation if the role of N in influencing freshwater ecosystem health is to be better understood, underpinning the implementation of the EU Water Framework Directive for European freshwaters

Balans van de leefomgeving 2014 : de toekomst is nú

De Balans van de Leefomgeving geeft parlement, kabinet en samenleving een feitelijk onderbouwd inzicht in de huidige kwaliteit van de fysieke leefomgeving. De Balans is de tweejaarlijkse peilstok van het PBL die aangeeft in hoeverre de door de politiek zelf ten doel gestelde leefomgevingskwaliteit tijdig wordt bereikt. De Balans van de Leefomgeving 2014 heeft als motto meegekregen: de toekomst is nú