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The first results of the study of high-energy electron neutrino (ν_{e}) and muon neutrino (ν_{µ}) charged-current interactions in the FASERν emulsion-tungsten detector of the FASER experiment at the LHC are presented. A 128.8 kg subset of the FASERν volume was analyzed after exposure to 9.5 fb^{-1} of sqrt[s]=13.6 TeV pp data. Four (eight) ν_{e} (ν_{µ}) interaction candidate events are observed with a statistical significance of 5.2σ (5.7σ). This is the first direct observation of ν_{e} interactions at a particle collider and includes the highest-energy ν_{e} and ν_{µ} ever detected from an artificial source. The interaction cross section per nucleon σ/E_{ν} is measured over an energy range of 560-1740 GeV (520-1760 GeV) for ν_{e} (ν_{µ}) to be (1.2_{-0.7}^{+0.8})×10^{-38} cm^{2} GeV^{-1} [(0.5±0.2)×10^{-38} cm^{2} GeV^{-1}], consistent with standard model predictions. These are the first measurements of neutrino interaction cross sections in those energy ranges.

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We report the first direct observation of neutrino interactions at a particle collider experiment. Neutrino candidate events are identified in a 13.6 TeV center-of-mass energy pp collision dataset of 35.4 fb^{-1} using the active electronic components of the FASER detector at the Large Hadron Collider. The candidates are required to have a track propagating through the entire length of the FASER detector and be consistent with a muon neutrino charged-current interaction. We infer 153_{-13}^{+12} neutrino interactions with a significance of 16 standard deviations above the background-only hypothesis. These events are consistent with the characteristics expected from neutrino interactions in terms of secondary particle production and spatial distribution, and they imply the observation of both neutrinos and anti-neutrinos with an incident neutrino energy of significantly above 200 GeV.

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AIM: To retrospectively describe the performance of ultrasound guided thoracic epidural anaesthesia under sedation for anaesthesia management of open pyloromyotomy. BACKGROUND: Anaesthesia management for hypertrophic pylorus stenosis (HPS) is usually performed under general anaesthesia with tracheal intubation. Only a few publications describe avoidance of tracheal intubation in infants by using spinal or caudal anaesthesia. The present retrospective analysis describes the performance of ultrasound guided thoracic epidural anaesthesia under sedation for anaesthetic management of open pyloromyotomy. METHODS: Twenty consecutive infants scheduled for pyloromyotomy according to the Weber-Ramstedt technique were retrospectively analysed. After sedation with nalbuphine and propofol, an ultrasound guided single shot thoracic epidural anaesthesia was performed with 0.75 ml·kg(-1) ropivacaine 0.475%. Insufficient blockade was defined as increase of HR > 15% from initial value and/or any movements at skin incision. In those cases we were prepared for rapid sequence intubation according to the departmental standard. RESULTS: All pyloromyotomies could be performed under single shot thoracic epidural anaesthesia and sedation. One case of moderate oxygen desaturation was treated with intermittent ventilation via face mask. CONCLUSIONS: Thoracic epidural anaesthesia under sedation for pyloromyotomy has been a useful technique in this retrospective series of infants suffering from HPS. In 1/20 infants short term assisted ventilation via face mask was required. Undisturbed surgery was possible in all cases.

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OBJECTIVE: In pediatric intensive care, two approaches to parenteral nutrition are available: individualized admixtures or commercial standard solutions. Even though individualized admixtures can be tailored to sometimes highly intricate requirements, standard solutions are able to meet the demands of the majority of pediatric patients. To address the growing importance of costs in intensive care, we investigated whether relevant differences between individualized admixtures and standard solutions in terms of costs can be found. DESIGN: Retrospective analysis. SETTING: University-affiliated intensive care unit. PATIENTS: Fifty consecutively admitted pediatric patients requiring parenteral nutrition. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Comparison of actual costs of individualized admixtures and theoretical costs of standard solutions. Mean actual costs of individualized admixtures of Euro 81.78 (+/- 16.33) per patient and day were significantly higher than the theoretical costs of standard solutions of Euro 61.21 (+/- 6.55). Cost differences increased with patients' body weights. CONCLUSIONS: Parenteral nutrition with standard solutions offers the potential of a relevant cost reduction compared with individualized admixtures in critically ill children.

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BACKGROUND: Albumin and plasma cholinesterase are markedly reduced in critical illness. However, the plasma half-lives of these two proteins have only been determined in very limited numbers of patients mostly outside intensive care. Therefore, we determined the kinetics of decrease of albumin and cholinesterase in a large population of critically ill patients. METHODS: Medical records of all patients of two university-affiliated surgical intensive care units during a time period of 8 years were retrospectively evaluated. To calculate the rate of fall, the first value in every episode of decreasing albumin or cholinesterase was arbitrarily set at 100% and the ensuing lower values were expressed as the respective fractions. RESULTS: Records of 3591 patients were evaluated. Regression analysis exhibited an exponential evolution of albumin and cholinesterase over time with corresponding mean apparent plasma half-lives of 11.8 days [95% confidence interval (CI): 10.8-12.9] for albumin and 7.8 days (95% CI: 7.4-8.3) for cholinesterase. CONCLUSIONS: These findings suggest that the apparent plasma half-lives of albumin and cholinesterase in critically ill surgical patients are considerably shorter than previously determined.

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