Climate effects of recycled fertilizers and biochar: emissions of nitrous oxide, methane and ammonia in a field experiment

Background Nitrogen (N) fertilizers are essential for crop production. Farmyard manure and slurry traditionally constitute about half of the total N inputs into crop production in Switzerland. Recycled fertilizers such as biogas slurry, liquid digestates and compost enable simultaneous energy production and closing of nutrient cycles. There is evidence that recycled fertilizers can help to increase N use efficiencies and to improve N supply in organic farming. Biochar amendment has shown a potential to mitigate soil greenhouse gas (GHG) emissions, in particular nitrous oxide (N2O) emissions. Here, we combine one of the liquid recycled fertilizer treatments with biochar. In a 2.5-years on-farm experiment, we quantify GHG emissions and further gaseous N-losses via ammonia (NH3) emissions

Modeling Scale-Dependent Bias on the Baryonic Acoustic Scale with the Statistics of Peaks of Gaussian Random Fields

Models of galaxy and halo clustering commonly assume that the tracers can be treated as a continuous field locally biased with respect to the underlying mass distribution. In the peak model pioneered by Bardeen et al. [Astrophys. J. 304, 15 (1986)], one considers instead density maxima of the initial, Gaussian mass density field as an approximation to the formation site of virialized objects. In this paper, the peak model is extended in two ways to improve its predictive accuracy. First, we derive the two-point correlation function of initial density peaks up to second order and demonstrate that a peak-background split approach can be applied to obtain the k-independent and k-dependent peak bias factors at all orders. Second, we explore the gravitational evolution of the peak correlation function within the Zel’dovich approximation. We show that the local (Lagrangian) bias approach emerges as a special case of the peak model, in which all bias parameters are scale independent and there is no statistical velocity bias. We apply our formulas to study how the Lagrangian peak biasing, the diffusion due to large scale flows, and the mode coupling due to nonlocal interactions affect the scale dependence of bias from small separations up to the baryon acoustic oscillation (BAO) scale. For 2σ density peaks collapsing at z = 0.3, our model predicts a ~5% residual scale-dependent bias around the acoustic scale that arises mostly from first order Lagrangian peak biasing (as opposed to second order gravity mode coupling). We also search for a scale dependence of bias in the large scale autocorrelation of massive halos extracted from a very large N-body simulation provided by the MICE Collaboration. For halos with mass M ≳ 1014M⊙/h, our measurements demonstrate a scale-dependent bias across the BAO feature which is very well reproduced by a prediction based on the peak model

What do District Health Planners in Tanzania think about improving priority setting using 'Accountability for Reasonableness'?

<p>Abstract</p> <p>Background</p> <p>Priority setting in every health system is complex and difficult. In less wealthy countries the dominant approach to priority setting has been Burden of Disease (BOD) and cost-effectiveness analysis (CEA), which is helpful, but insufficient because it focuses on a narrow range of values – need and efficiency – and not the full range of relevant values, including legitimacy and fairness. 'Accountability for reasonableness' is a conceptual framework for legitimate and fair priority setting and is empirically based and ethically justified. It connects priority setting to broader, more fundamental, democratic deliberative processes that have an impact on social justice and equity. Can 'accountability for reasonableness' be helpful for improving priority setting in less wealthy countries?</p> <p>Methods</p> <p>In 2005, Tanzanian scholars from the Primary Health Care Institute (PHCI) conducted 6 capacity building workshops with senior health staff, district planners and managers, and representatives of the Tanzanian Ministry of Health to discussion improving priority setting in Tanzania using 'accountability for reasonableness'. The purpose of this paper is to describe this initiative and the participants' views about the approach.</p> <p>Results</p> <p>The approach to improving priority setting using 'accountability for reasonableness' was viewed by district decision makers with enthusiastic favour because it was the first framework that directly addressed their priority setting concerns. High level Ministry of Health participants were also very supportive of the approach.</p> <p>Conclusion</p> <p>Both Tanzanian district and governmental health planners viewed the 'accountability for reasonableness' approach with enthusiastic favour because it was the first framework that directly addressed their concerns.</p

Analysis of Compound Synergy in High-Throughput Cellular Screens by Population-Based Lifetime Modeling

Despite the successful introduction of potent anti-cancer therapeutics, most of these drugs lead to only modest tumor-shrinkage or transient responses, followed by re-growth of tumors. Combining different compounds has resulted in enhanced tumor control and prolonged survival. However, methods querying the efficacy of such combinations have been hampered by limited scalability, analytical resolution, statistical feasibility, or a combination thereof. We have developed a theoretical framework modeling cellular viability as a stochastic lifetime process to determine synergistic compound combinations from high-throughput cellular screens. We apply our method to data derived from chemical perturbations of 65 cancer cell lines with two inhibitors. Our analysis revealed synergy for the combination of both compounds in subsets of cell lines. By contrast, in cell lines in which inhibition of one of both targets was sufficient to induce cell death, no synergy was detected, compatible with the topology of the oncogenically activated signaling network. In summary, we provide a tool for the measurement of synergy strength for combination perturbation experiments that might help define pathway topologies and direct clinical trials

Turnover of Phosphatidic Acid through Distinct Signaling Pathways Affects Multiple Aspects of Pollen Tube Growth in Tobacco

Phosphatidic acid (PA) is an important intermediate in membrane lipid metabolism that acts as a key component of signaling networks, regulating the spatio-temporal dynamics of the endomembrane system and the cytoskeleton. Using tobacco pollen tubes as a model, we addressed the signaling effects of PA by probing the functions of three most relevant enzymes that regulate the production and degradation of PA, namely, phospholipases D (PLD), diacylglycerol kinases (DGKs), and lipid phosphate phosphatases (LPPs). Phylogenetic analysis indicated a highly dynamic evolution of all three lipid-modifying enzymes in land plants, with many clade-specific duplications or losses and massive diversification of the C2-PLD family. In silico transcriptomic survey revealed increased levels of expression of all three PA-regulatory genes in pollen development (particularly the DGKs). Using specific inhibitors we were able to distinguish the contributions of PLDs, DGKs, and LPPs into PA-regulated processes. Thus, suppressing PA production by inhibiting either PLD or DGK activity compromised membrane trafficking except early endocytosis, disrupted tip-localized deposition of cell wall material, especially pectins, and inhibited pollen tube growth. Conversely, suppressing PA degradation by inhibiting LPP activity using any of three different inhibitors significantly stimulated pollen tube growth, and similar effect was achieved by suppressing the expression of tobacco pollen LPP4 using antisense knock-down. Interestingly, inhibiting specifically DGK changed vacuolar dynamics and the morphology of pollen tubes, whereas inhibiting specifically PLD disrupted the actin cytoskeleton. Overall, our results demonstrate the critical importance of all three types of enzymes involved in PA production and degradation, with strikingly different roles of PA produced by the PLD and DGK pathways, in pollen tube growth

Listeria monocytogenes Infection in Macrophages Induces Vacuolar-Dependent Host miRNA Response

Listeria monocytogenes is a Gram-positive facultative intracellular pathogen, causing serious illness in immunocompromised individuals and pregnant women. Upon detection by macrophages, which are key players of the innate immune response against infection, L. monocytogenes induces specific host cell responses which need to be tightly controlled at transcriptional and post-transcriptional levels. Here, we ask whether and how host miRNAs, which represent an important mechanism of post-transcriptional regulation in a wide array of biological processes, are altered by a model pathogen upon live infection of murine bone marrow derived macrophages. We first report that L. monocytogenes subverts the host genome-wide miRNA profile of macrophages in vitro. Specifically, we show that miR-155, miR-146a, miR-125a-3p/5p and miR-149 were amongst the most significantly regulated miRNAs in infected macrophages. Strikingly, these miRNAs were highly upregulated upon infection with the Listeriolysin-deficient L. monocytogenes mutant Δhly, that cannot escape from the phagosome thus representing a vacuolar-contained infection. The vacuolar miRNA response was significantly reduced in macrophages deficient for MyD88. In addition, miR-146a and miR-125a-3p/5p were regulated at transcriptional levels upon infection, and miR-125a-3p/5p were found to be TLR2 responsive. Furthermore, miR-155 transactivation in infection was regulated by NF-κB p65, while miR-146a and miR-125a-3p/5p expression was unaffected in p65-deficient primary macrophages upon L. monocytogenes infection. Our results demonstrate that L. monocytogenes promotes significant changes in the miRNA expression profile in macrophages, and reveal a vacuolar-dependent miRNA signature, listeriolysin-independent and MyD88-dependent. These miRNAs are predicted to target immune genes and are therefore most likely involved in regulation of the macrophage innate immune response against infection at post-transcriptional levels

Bucki (2006), Rapid erosion of soft sediments by tidewater glacier advance: Taku Glacier

[1] Taku Glacier in southeast Alaska has advanced 7.5 km over the last 115 years, overriding its own glaciomarine and outwash sediments. We have documented rapid erosion of these sediments by comparing radio echo soundings (RES) along five transects (2003)(2004)(2005) to earlier RES surveys (1989 and 1994) and to early bathymetric surveys of the proglacial fjord. Erosion rates, _ E, reached 3.9 ± 0.8 m

Star formation towards the Scutum tangent region and the effects of Galactic environment

By positional matching to the catalogue of Galactic Ring Survey molecular clouds, we have derived distances to 793 Bolocam Galactic Plane Survey (BGPS) sources out of a possible 806 located within the region defined by Galactic longitudes l = 28.5 degr to 31.5 degr and latitudes |b| < 1 degr. This section of the Galactic Plane contains several major features of Galactic structure at different distances, mainly mid-arm sections of the Perseus and Sagittarius spiral arms and the tangent of the Scutum-Centarus arm, which is coincident with the end of the Galactic Long Bar. By utilising the catalogued cloud distances plus new kinematic distance determinations, we are able to separate the dense BGPS clumps into these three main line-of-sight components to look for variations in star-formation properties that might be related to the different Galactic environments. We find no evidence of any difference in either the clump mass function or the average clump formation efficiency (CFE) between these components that might be attributed to environmental effects on scales comparable to Galactic-structure features. Despite having a very high star-formation rate, and containing at least one cloud with a very high CFE, the star formation associated with the Scutum-Centarus tangent does not appear to be in any way abnormal or different to that in the other two spiral-arm sections. Large variations in the CFE are found on the scale of individual clouds, however, which may be due to local triggering agents as opposed to the large-scale Galactic structure.Comment: 11 pages, 8 figures. Accepted for publication in the Monthly Notices of the Royal Astronomical Societ

Flat galaxies with dark matter halos - existence and stability

We consider a model for a flat, disk-like galaxy surrounded by a halo of dark matter, namely a Vlasov-Poisson type system with two particle species, the stars which are restricted to the galactic plane and the dark matter particles. These constituents interact only through the gravitational potential which stars and dark matter create collectively. Using a variational approach we prove the existence of steady state solutions and their nonlinear stability under suitably restricted perturbations.Comment: 39 page