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Site-specific effects of nitrification inhibitors on N<sub>2</sub>O emissions from manure and urea ammonium nitrate
No full textNitrification inhibitors (NIs) can be an effective measure to mitigate nitrous oxide (N2O) emissions from agricultural soils. Meta-analyses indicate that the efficacy of NIs is influenced by soil properties and climate, but such effects have rarely been investigated by direct comparisons across field sites. Using four experimental field sites across Denmark, this study investigated the interacting effects of fertiliser type, soil type and rainfall on N2O emissions and effects of two different NIs after spring fertilisation of spring barley in 2022 and 2023. The fertiliser materials included cattle slurry (CS), pig slurry (PS) and urea ammonium nitrate (UAN, 2022 only), applied at recommended rates with or without 3,4-dimethylpyrazole phosphate (DMPP) or 2-chloro-6-(trichloromethyl) pyridine (nitrapyrin, NP), along with an unfertilised control. Rainfall was close to the long-term average at Askov and Vejen in 2022 but below average in the six other monitoring periods. The increase in net cumulative N2O emissions from manure application without NIs varied between 0.16 and 1.5 kg N ha−1 while with UAN it was between 0.05 and 0.46 kg N ha−1. The amendment of NIs significantly reduced N2O emissions but only the coarse sandy soil at Vejen showed consistent and large reductions with NI amendment leading to average reductions of 83 %, 67 %, and 77 % for cattle slurry, pig slurry, and UAN, respectively. Specific site effects of NI were attributed to differences in gas and solute diffusivity, and NI availability, across sites and years. In this study, NI amendment to synthetic N fertiliser and, especially, manure applied to sandy soil had the greatest N2O mitigation potential, suggesting targeted use of NIs on sandy soil as a strategic N2O mitigation scenario.</p
Modal remoteness in a grammatical description of Danish from 1901
No full textIn the paper it is described how the Danish grammarian Hylling Georg Wiwel (1851-1910) already in 1901 anticipated the concept of “modal remote-ness” by analyzing the modal uses of the Danish Past tense. Subsequently, it is demonstrated how the ideas of Wiwel have changed the Danish gram-matical tradition with important consequences for even very recent grammars. Finally, it is discussed whether the Danish experiences have some relevance for the grammatical description of the similar Italian phenomena.Keywords: Modal Remoteness; Danish Verbal System; Past Tense; H.G. Wiwel; E. Hansen; L. Heltoft
Probabilities of finding trace profile donors and their paternal relatives in Y-STR reference databases
No full textForensic investigative genetic genealogy using Y-chromosome short tandem repeat (Y-STR) DNA profiles can give investigative leads in criminal cases by searching for the Y-STR trace profile or similar but not identical Y-STR profiles in relevant Y-STR databases. We conducted a simulation study with YfilerTM Plus and PowerPlex® Y23 Y-STR profiles to estimate the probabilities of finding matches and near-matches in Y-STR databases. The success rate of finding the trace profile donors or their close relatives was quantified. We used the malan R software package to simulate the populations based on the Wright-Fisher model with the YHRD Y-STR mutation rates where uncertainties were incorporated in a Bayesian manner, a variance in reproductive success of 0.2, and a constant size for 100 generations followed by a 2% growth for 150 generations. Y-STR databases were generated by randomly drawing Y-STR profiles from a YfilerTM Plus and PowerPlex® Y23 Y-STR population data set, respectively. In a population of 500,066 individuals, a database size of 0.5% of the population resulted in a Y-STR database match probability of ca. 6% and 10% for YfilerTM Plus and PowerPlex® Y23, respectively. Increasing the database size to 5% of the population resulted in a Y-STR match probability of ca. 41% and 54% for YfilerTM Plus and PowerPlex® Y23, respectively. When a Y-STR match was found in the database, the probability of one of the individuals with the matching profiles being related within five meioses to the trace donor was ca. 64% and 56% for YfilerTM Plus and PowerPlex® Y23, respectively, including the cases where the Y-STR profile originated from the donor. In this case, the closest relative in the database was found among the matching individuals with a probability of ca. 91%.</p
Superradiant amplification by rotating viscous compact objects
No full textWe study fluctuations of rotating viscous stars, using the causal relativistic hydrodynamics of Bemfica, Disconzi, Kovtun, and Noronha. We derive, in a slow-rotation approximation, a coupled system of equations describing the propagation of axial gravitational waves through the star, which couple to internal viscous modes. We show that rotating viscous stars amplify incoming low-frequency gravitational waves, a phenomenon which we argue to be universal. Superradiant amplification does not seem to trigger an instability for uniformly rotating stars, even if the object is compact enough to have light rings
Assessment of the economic impact of disease outbreaks and mortality losses in rainbow trout aquaculture in Denmark
No full textDisease control is one of the bottlenecks for the further development of sustainable aquaculture. Studies quantifying the economic costs of fish diseases are still inadequate because of the scarce availability of actual data. Data was collected successfully from one of the leading aquaculture companies in Denmark in this study. An investigation of the economic costs associated with mortality in rainbow trout (Oncorhynchus mykiss) farming on a RAS (Recirculating Aquaculture System) farm (freshwater) and a sea cage farm (saltwater) was carried out over three production cycles from 2018 to 2020. The costs associated with mortality per kg ranged from 0.22 USD to 0.50 USD in sea cage farming and 0.09 USD to 0.17 USD in the RAS facility. The findings revealed that losses of feed and biomass were responsible for the majority of the mortality cost, whereas the medication cost had a significant effect on both production facilities. The sensitivity analysis revealed that freshwater farming resulted in mortality at a low level with comparatively successful disease management, whereas once high mortality was reported, its economic impacts were expected to be substantial. In contrast, the net operating profit was robustly positive in saltwater until 57 % mortality was reached. The findings of our study emphasize the importance of maintaining robust disease control and preventing disease entry into RASs
Spline Refinement with Differentiable Rendering
No full textDetecting slender, overlapping structures remains a challenge in computational microscopy. While recent coordinate-based approaches improve detection, they often produce less accurate splines than pixel-based methods. We introduce a training-free differentiable rendering approach to spline refinement, achieving both high reliability and sub-pixel accuracy. Our method improves spline quality, enhances robustness to distribution shifts, and shrinks the gap between synthetic and real-world data. Being fully unsupervised, the method is a drop-in replacement for the popular active contour model for spline refinement. Evaluated on C. elegans nematodes, a popular model organism for drug discovery and biomedical research, we demonstrate that our approach combines the strengths of both coordinate- and pixel-based methods.</p
Vaccine Denialism
No full textVaccine denialists report being derided for their views in clinical settings, and they are routinely ignored or silenced in mainstream public conversations and policymaking. Denialism tends to figure as an obstacle to be dealt with, and as a target of policymaking aiming to reduce the incidence or harmful side effects, as if denialism were some kind of infectious disease. This chapter discusses the epistemic exclusion of the vaccine denialists and the justification of this exclusion. It argues that it is not obvious that a vaccine denialist need be epistemically irrational or epistemically blameworthy. The chapter proposes to understand the normative assessment of epistemic exclusion in terms of two concepts of epistemic respect—epistemic appraisal respect and epistemic recognition respect. In this chapter, this framework to vaccine denialism is applied in different contexts
Compact 1 GHz electron paramagnetic resonance spectrometer and imager
No full textA 1 GHz preclinical electron paramagnetic resonance spectrometer and imager has been developed to study low concentrations of radicals using rapid-scan detection. The design focuses on minimizing the losses between the resonator and the first-stage low-noise amplifier. The adjustable-frequency source with the lowest available noise was selected and the output was amplified to provide sufficient power for experiments with relatively rapidly relaxing nitroxide radicals. For resonators with similar geometries and efficiencies, improved signal to noise was demonstrated relative to our previous instrument that operates at 700 MHz, consistent with predictions for frequency dependence. System performance was demonstrated for solutions of nitroxide radicals in resonators that contain 8 mm or 25 mm diameter cylindrical tubes. For N-15-d(16) tempone in aqueous solution and a signal averaging time of 3.8 s, a signal-to-noise of 3 required 2 x 10(14) spins in the 8 mm resonator or 4.5 x 10(15) spins in the 25 mm resonator. 3D spatial imaging was demonstrated with a phantom consisting of three tubes containing solutions of a nitroxide radical
Volumetric absorptive microsampling and conductive vial electromembrane extraction for the analysis of pharmaceuticals in whole blood
No full textVolumetric absorptive microsampling (VAMS) enables accurate collection of low blood volumes, independent of hematocrit. Electromembrane extraction (EME) is a sustainable sample clean-up technique; however, its wider applicability to extract analytes directly from VAMS tips remains unexplored. This study aimed to evaluate applicability of the first commercially available conductive vial EME device (with 2-nitrophenyl octyl ether as liquid membrane) for isolating 41 basic pharmaceuticals (log P 2–6) from 10 μL of blood on VAMS tips. The following extraction parameters were optimized: donor solution composition and volume, conductive vials size, applied voltage, extraction time and agitation speed. It was found that: 1/large conductive vials (600 μL) and 300 μL of donor solution provide higher process efficiency and reproducibility compared to smaller vials (200 μL) or larger donor solution volumes; 2/methanol in donor solution improve reproducibility and 3/sonication of VAMS tips in donor solution within a conductive vial prior to extraction enhances process efficiency. The EME protocol, followed by UHPLC-MS/MS analysis, was evaluated for process efficiency, linearity (1–1000 ng/mL), precision, and accuracy. Eleven analytes met most of the predefined acceptance criteria: process efficiencies 34.9–65.8 %, linearity (R2) 0.9933–0.9995, accuracy 85.9–111.1 % and precision 1.4–13.3 % RSD. The extraction was not impacted by hematocrit variation. EME demonstrated superior reproducibility and reduced matrix effects when compared to conventional VAMS tips treatment. This study confirms the reliability of a commercial conductive vial EME device for isolating basic pharmaceuticals from whole blood on VAMS tips, highlighting its potential for routine bioanalytical applications.</p
