Medium-term exposure of the North Atlantic copepod Calanus finmarchicus (Gunnerus, 1770) to CO2-acidified seawater: effects on survival and development

The impact of medium-term exposure to CO2-acidified seawater on survival, growth and development was investigated in the North Atlantic copepod Calanus finmarchicus. Using a custom developed experimental system, fertilized eggs and subsequent development stages were exposed to normal seawater (390 ppm CO2) or one of three different levels of CO2-induced acidification (3300, 7300, 9700 ppm CO2). Following the 28-day exposure period, survival was found to be unaffected by exposure to 3300 ppm CO2, but significantly reduced at 7300 and 9700 ppm CO2. Also, the proportion of copepodite stages IV to VI observed in the different treatments was significantly affected in a manner that may indicate a CO2-induced retardation of the rate of ontogenetic development. Morphometric analysis revealed a significant increase in size (prosome length) and lipid storage volume in stage IV copepodites exposed to 3300 ppm CO2 and reduced size in stage III copepodites exposed to 7300 ppm CO2. Together, the findings indicate that a pCO2 level ≤2000 ppm (the highest CO2 level expected by the year 2300) will probably not directly affect survival in C. finmarchicus. Longer term experiments at more moderate CO2 levels are, however, necessary before the possibility that growth and development may be affected below 2000 ppm CO2 can be ruled out.© Author(s) 2013. This work is distributed under the Creative Commons Attribution 3.0 License

High patient satisfaction in 445 patients who underwent fast-track hip or knee replacement

Background and purpose — Patient satisfaction is important in fast-track total hip and knee replacement (THR, TKR). We assessed: (1) how satisfied patients were with the treatment; (2) factors related to overall satisfaction; and (3) whether there was a difference between THR and TKR regarding length of stay (LOS) and patient satisfaction. Patients and methods — In this follow-up study, a consecutive series of 445 patients undergoing THR and TKR completed a questionnaire 2 weeks after discharge. LOS and short-term patient satisfaction with the fast-track management were measured. Patient satisfaction was measured using a numerical rating scale (NRS; 0–10). Results — For THR, the median satisfaction score was 9–10 and for TKR it was 8.5–10 in all parameters. Older THR patients had higher overall satisfaction. No association was found between overall satisfaction following THR or TKR and sex comorbidity, or LOS. THR patients had shorter mean LOS than TKR patients, even though the median LOS was 2 days for both groups. THR patients were more satisfied than TKR patients in the first weeks after discharge. Interpretation — Patient satisfaction is high following fast-track THR and TKR, with scores ranging from 8.5 to 10 on the NRS. A qualitative investigation of the first weeks after discharge is required to learn more about how to improve the experience of recovery

Trends in Antibiotic Use by Birth Season and Birth Year

OBJECTIVES: We examined 2 birth cohort effects on antibiotic prescribing during the first year of life (henceforth, infancy) in Denmark: (1) the birth season effect on timing and overall occurrence of antibiotic prescribing, and (2) the birth year effect amid emerging nationwide pneumococcal vaccination programs and changing prescribing guidelines. METHODS: We linked data for all live births in Denmark from 2004 to 2012 (N = 561 729) across the National Health Service Prescription Database, Medical Birth Registry, and Civil Registration System. Across birth season and birth year cohorts, we estimated 1-year risk, rate, and burden of redeemed antibiotic prescriptions during infancy. We used interrupted time series methods to assess prescribing trends across birth year cohorts. Graphical displays of all birth cohort effect data are included. RESULTS: The 1-year risk of having at least 1 redeemed antibiotic prescription during infancy was 39.5% (99% confidence interval [CI]: 39.3% to 39.6%). The hazard of a first prescription increased with age throughout infancy and varied by season; subsequently, Kaplan-Meier-derived risk functions varied by birth season cohort. After rollout of a first vaccination program and new antibiotic prescribing guidelines, 1-year risk decreased by 4.4% over 14 months (99% CI: 3.4% to 5.5%); it decreased again after rollout of a second vaccination program by 6.9% over 3 years (99% CI: 4.4% to 9.3%). CONCLUSIONS: In Denmark, birth season and birth year cohort effects influenced timing and risk of antibiotic prescribing during infancy. Future studies of antibiotic stewardship, effectiveness, and safety in children should consider these cohort effects, which may render some children inherently more susceptible than others to downstream antibiotic effects

A new endstation for extreme-ultraviolet spectroscopy of free clusters and nanodroplets

We present a new endstation for the AMOLine of the ASTRID2 synchrotron at Aarhus University, which combines a cluster and nanodroplet beam source with a velocity map imaging and time-of-flight spectrometer for coincidence imaging spectroscopy. Extreme-ultraviolet spectroscopy of free nanoparticles is a powerful tool for studying the photophysics and photochemistry of resonantly excited or ionized nanometer-sized condensed-phase systems. Here we demonstrate this capability by performing photoelectron-photoion coincidence (PEPICO) experiments with pure and doped superfluid helium nanodroplets. Different doping options and beam sources provide a versatile platform to generate various van der Waals clusters as well as He nanodroplets. We present a detailed characterization of the new setup and present examples of its use for measuring high-resolution yield spectra of charged particles, time-of-flight ion mass spectra, anion-cation coincidence spectra, multi-coincidence electron spectra and angular distributions. A particular focus of the research with this new endstation is on intermolecular charge and energy-transfer processes in heterogeneous nanosystems induced by valence-shell excitation and ionization.Comment: 28 pages, 17 figures, submitted to Review of Scientific Instrument