The leading hadronic vacuum polarisation on the lattice

After discussing the relevance of a first principles theory-prediction of the hadronic vacuum polarisation for Standard Model tests, the theoretical challenges for its computation in lattice QCD are reviewed. New ideas that will potentially improve the quality of lattice simulations will be introduced and the status of ongoing simulations will be presented briefly.Comment: 3 pages, 4 figures, talk at "Quark Confinement and the Hadron Spectrum IX", Madrid, Spain, Aug. 30-Sep. 3, 2010; submitted to AIP Conference Proceeding

«Det absurde ved å være fanget i blodbankende materie». Om rus og litteratur i Ingvar Ambjørnsens ‘Skogens hjerte’

Artikkelen undersøker Ingvar Ambjørnsens novelle «Skogens hjerte» fra novellesamlingen Natt til mørk morgen (1997) og fokuserer på fremstillingen av ruserfaringer som står sentralt i teksten. Utgangspunktet for lesningen er Peter Sloterdijks beskrivelse av den historiske utviklingen av ruserfaringer fra antikken til det moderne. Hans forståelse finner man også i Ambjørnsens korttekst, men denne omfatter dessuten en bestemt bruk av intertekstualitet. Herved fokuseres det både på litterære (f.eks. Vesaas) og idéhistoriske referanser (Huxley). «Skogens hjerte» ble i tillegg det intertekstuelle forelegget for deler av Ambjørnsens roman Natten drømmer om dagen(2012). På en måte ‘sampler’ forfatteren sin egen novelle, som får en mer pessimistisk omfortolking.This article explores Norwegian author Ingvar Ambjørnsen’s short story «The Heart of the Forest» from his collection Dark Dawn (1997) and focuses on the story’s prime experience, that of drugs. Peter Sloterdijk’s account of the historical development of drugs from the early Greek era to modernity is the theoretical framework. His understanding is found in Ambjørnsen’s short text, which also contains a notion of intertextuality. Therefore, the article highlights both literary (Vesaas) and philosophical references (Huxley). «The Heart of the Forest» is also the precursor for Ambjørnsen’s novel The Night Dreaming of Day (2012), which implies that the author sampled his own short story and gave it a pessimistic reinterpretation.publishedVersio

Testing a simple energy-budget model for yolk-feeding stages of cleaner fish

The use of cleaner fish is an environmentally-friendly approach to combat the salmon louse, threatening commercial salmon farming. Dynamic Energy Budget (DEB) modelling helps understand the bioenergetics of early life stages of the cleaner fish, and can thereby aid optimisation of their culturing. Here, we report on our attempts to parametrise DEBkiss models for the yolk-feeding stages of two cleaner fish species, ballan wrasse (Labrus bergylta) and lumpfish (Cyclopterus lumpus). A range of measurements was taken over early development, including biometry (using imaging), weight and composition, as well as measurements of respiration rate. Despite the previous success of applying the DEBkiss model to early life stages of Atlantic cod, the model failed to capture the patterns of yolk depletion for ballan wrasse. The main issues were related to substantial changes in the water content of both yolk and structure over development, and a stop of growth before disappearance of the yolk sac. These issues require further experimental work to address, especially more efficient proxies for the dry mass of yolk and structure, such that these compartments can be efficiently separated. Nevertheless, apart from the pattern of yolk depletion, the model provides a reasonable explanation of all traits simultaneously. This indicates that model modifications may only need to be minor. For lumpfish, the data set was quite limited for testing of the DEBkiss model, due to the opacity of the egg and the fact that there was only one time point with measurements post hatch. Nevertheless, the data are consistent with the model. The modelling results indicate that both cleaner-fish species may have very similar bioenergetic parameters (and quite similar to Atlantic cod as well); the conspicuous difference in early life history may be mainly caused by the larger yolk provisioning in the egg, and late hatching, in lumpfish. The DEBkiss model is a simple and promising tool for bioenergetics of fish early-life stages. However, its application and in-depth testing is currently limited by the difficulties of obtaining detailed measurements on these life stages.publishedVersio

Another Look at Minimal Lepton Flavour Violation, l_i -> l_j gamma, Leptogenesis, and the Ratio M_nu/ Lambda_LFV

We analyze lepton flavour violation (LFV), as well as generation of the observed baryon-antibaryon asymmetry of the Universe (BAU) within a generalized minimal lepton flavour violation (MLFV) framework where we allow for CP violation both at low and high energies. The generation of BAU is obtained through radiative resonant leptogenesis (RRL), where starting with three exactly degenerate right-handed neutrinos at Lambda_GUT, we demonstrate explicitly within the SM and the MSSM that the splittings between their masses at the see-saw scale M_nu, generated by renormalization group effects, are sufficient for a successful leptogenesis for M_nu even as low as 10^6 GeV. The inclusion of flavour effects plays an important role in this result and can lead to the observed BAU even in the absence of CP violation beyond the PMNS phases. The absence of a stringent lower bound on M_nu in this type of leptogenesis allows to easily satisfy present and near future upper bounds on mu -> e gamma and other charged lepton flavour violating (LFV) processes even for Lambda_LFV = O(1 TeV). We find, that the MLFV framework in the presence of heavy right-handed neutrinos and leptogenesis is not as predictive as MFV in the quark sector and point out that without a specific MLFV model, there is a rich spectrum of possibilities for charged LFV processes and for their correlation with low energy neutrino physics and the LHC physics, even if the constraint from the observed BAU is taken into account. While certain qualitative features of our analysis confirm findings of Cirigliano et al., at the quantitative level we find phenomenologically important differences. We explain the origin of these differences.Comment: 48 pages, 9 figure

Fourteen-Day Bactericidal Activity, Safety, and Pharmacokinetics of Linezolid in Adults with Drug-Sensitive Pulmonary Tuberculosis

CITATION: Diacon AH, De Jager VR, Dawson R, Narunsky K, Vanker N, Burger DA, Everitt D, Pappas F, Nedelman J, Mendel CM. 2020. Fourteen-day bactericidal activity, safety, and pharmacokinetics of linezolid in adults with drug-sensitive pulmonary tuberculosis. Antimicrob Agents Chemother 64:e02012-19. https://doi.org/10.1128/AAC.02012-19.Background: Linezolid is increasingly used for the treatment of tuberculosis resistant to first-line agents, but the most effective dosing strategy is yet unknown. Methods: Between November 2014 and November 2016, we randomised 114 drug-sensitive treatment-naïve pulmonary tuberculosis patients from Cape Town, South Africa, to one of six 14-day treatment arms containing linezolid 300 mg once daily (qd), 300 mg twice daily (bd), 600 mg qd, 600 mg bd, 1200 mg qd, 1200 mg three times per week (tiw) or a combination of isoniazid, rifampicin, pyrazinamide and ethambutol. Sixteen-hour sputum samples were collected overnight, and bactericidal activity characterized by the daily percentage change in time to positivity (TTP) and colony forming units (CFU). We also assessed the safety and pharmacokinetics of the study treatments. Results: Bactericidal activity increased with increasing doses of linezolid. Based on the daily percentage change in TTP, activity was highest for 1200 mg qd (4.5; 95% Bayesian confidence interval [BCI]: 3.3-5.6), followed by 600 mg bd (4.1; BCI: 2.5-5.7), 600 mg qd (4.1; BCI: 2.9-5.3), 300 mg bd (3.3; BCI: 1.9-4.7), 300 mg qd (2.3; BCI: 1.1-3.5) and 1200 mg tiw (2.2; BCI: 1.1-3.3). Similar results were seen with bactericidal activity characterized by the daily rate of change in CFU count. Antimycobacterial activity correlated positively with plasma drug exposure and percentage time over minimum inhibitory concentration. There were no unexpected adverse events. Conclusion: All linezolid doses showed bactericidal activity. For the same total daily dose, once daily dosing proved to be at least as effective as a divided twice daily dose. An intermittent dosing regimen, with 1200 mg given three times weekly, showed the least activity

Retinol and Retinol Binding Protein 4 Levels and Cardiometabolic Disease Risk

Background: Despite mechanistic studies linking retinol and RBP4 (retinol binding protein 4) to the pathogenesis of cardiovascular diseases (CVD) and type 2 diabetes (T2D), epidemiological evidence is still conflicting. We investigated whether conflicting results of previous studies may be explained by differences in the association of retinol and RBP4 with cardiometabolic risk across subgroups with distinct sex, hypertension state, liver, or kidney function. Methods: We used case-cohorts nested in the EPIC (European Prospective Investigation Into Cancer and Nutrition)-Potsdam cohort (N=27 548) comprising a random sample of participants (n=2500) and all physician-verified cases of incident CVD (n=508, median follow-up time 8.2 years) and T2D (n=820, median follow-up time 6.3 years). We estimated nonlinear and linear multivariable-adjusted associations between the biomarkers and cardiometabolic diseases by restricted cubic splines and Cox regression, respectively, testing potential interactions with hypertension, liver, and kidney function. Additionally, we performed 2-sample Mendelian Randomization analyses in publicly available data. Results: The association of retinol with cardiometabolic risk was modified by hypertension state (P interaction CVDP interaction T2D<0.001). Retinol was associated with lower cardiometabolic risk in participants with treated hypertension (hazard ratio(per SD) [95% CI]: CVD, 0.71 [0.56-0.90]; T2D, 0.81 [0.70-0.94]) but with higher cardiometabolic risk in normotensive participants (CVD, 1.32 [1.06-1.64]; T2D, 1.15 [0.98-1.36]). Our analyses also indicated a significant interaction between RBP4 and hypertension on CVD risk (P interaction=0.04). Regarding T2D risk, we observed a u-shaped association with RBP4 in women (P nonlinearity=0.01, P effect=0.02) and no statistically significant association in men. The biomarkers\u27 interactions with liver or kidney function were not statistically significant. Hypertension state-specific associations for retinol concentrations with cardiovascular mortality risk were replicated in National Health and Nutrition Examination Survey III. Conclusions: Our findings suggest a hypertension-dependent relationship between plasma retinol and cardiometabolic risk and complex interactions of RBP4 with sex and hypertension on cardiometabolic risk