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The trace metals zinc (Zn) and cadmium (Cd) are both involved in the metabolic processes of marine phytoplankton, and as such, both metals play important roles in ocean biogeochemical cycles. In Antarctica, the Amundsen Sea (AS) experiences rapid ice shelf melting, and the Amundsen Sea polynya (ASP) hosts seasonal phytoplankton blooms in austral summer, with important implications for atmospheric carbon dioxide drawdown. However, the effects of ice melting and phytoplankton blooms on the biogeochemistry and distributions of Zn and Cd in the ASP remain poorly studied. Here, we present the first combined dataset of dissolved and particulate Zn and Cd in the AS (including the inflow and outflow to and from the Dotson and Getz ice shelves) collected as part of the GEOTRACES process study GPpr12. We use this dataset to assess the sources of both elements to the AS region and characterize the particle composition in the ASP. We find that the main source of both dissolved Zn and Cd in the AS is Circumpolar Deep Water (CDW), with an additional small flux of both metals from shelf sediments. By contrast, aerosol deposition, ice shelf melt, and sea ice melt are all deemed insignificant sources for either Zn or Cd in the AS. Labile particulate Zn and Cd dominate the total particulate pool in the surface layer, indicating that biological uptake is a predominant process for the cycling of both metals in the ASP, whereas sediment resuspension and ice shelf melt do not supply a significant amount of either particulate Zn or Cd. Additionally, we use two commonly used approaches to estimate biogenic and lithogenic particulate concentrations. We find high biogenic particulate concentrations at the surface, decreasing with depth, indicating remineralization plays an important role in the cycling of particulate metals. In contrast, lithogenic particulate metal concentrations remain low throughout the water column. We also show that the estimated uptake ratios of Zn and Cd relative to p

The German Scientific Working Group for Paediatric Anaesthesia (Wissenschaftlicher Arbeitskreis Kinderansthesie, WAKKA) of the German Society for Anaesthesia and Intensive Care Medicine (DGAI) has updated their current recommendations on preoperative fasting in children from 2007, along with the preoperative fasting statement of the German Association of Anaesthesiologists (Berufsverband Deutscher Anasthesisten, BDA) and DGAI from 2016 in agreement with the new evidence-based European Guideline of the European Society of Anaesthesiology and Intensive Care (ESAIC) of 2022 - and transferred it into the S1 Guideline format of the Association of the Scientific. Medical Societies in Germany (Arbeitsgemeinschaft der Wissenschaftlichen Medizinischen Fachgeselischaften e. V., AWMF). This revision became necessary because recent studies had shown that optimized fasting times improved hornoeostasis and well-being of the children, while the risk of regurgitation and aspiration had not increased. On the other hand, long periods of fasting might be the cause of misbehaviour, stress, iatrogenic dehydration and catabolism. The updated S1 Guideline therefore recommends shorter fasting times of 4 hours for small, light meals and/or formula or cow's milk (still 6 hours for a full meal), 3 hours for breast milk, and 1 hour for clear fluids (6-4-3-1 Rule). In addition, the new S1 Guideline contains further recommendations for children with concomitant diseases that are of relevance to anaesthesia, for the application of ultrasound to examine the stomach content prior to the induction of anaesthesia, for postoperative fasting and the implementation of the new rules in clinical practice.

Whether phytoplankton mortality is caused by grazing or viral lysis has important implications for phytoplankton dynamics and biogeochemical cycling. The ecological relevance of viral lysis for Antarctic phytoplankton is still under-studied. The Amundsen Sea is highly productive in spring and summer, especially in the Amundsen Sea Polynya (ASP), and very sensitive to global warming-induced ice-melt. This study reports on the importance of the viral lysis, compared to grazing, of pico- and nanophytoplankton, using the modified dilution method (based on apparent growth rates) in combination with flow cytometry and size fractionation. Considerable viral lysis was shown for all phytoplankton populations, independent of sampling location and cell size. In contrast, the average grazing rate was 116% higher for the larger nanophytoplankton, and grazing was also higher in the ASP (0.45 d−1 vs. 0.30 d−1 outside). Despite average specific viral lysis rates being lower than grazing rates (0.17 d−1 vs. 0.29 d−1), the averageamount of phytoplankton carbon lost was similar (0.6 µg C L−1 d −1 each). The viral lysis of the larger-sized phytoplankton populations (including diatoms) and the high lysis rates of the abundant P. antarctica contributed substantially to the carbon lost. Our results demonstrate that viral lysis is a principal loss factor to consider for Southern Ocean phytoplankton communities and ecosystem production.

Polar seas are under threat of enhanced UV-radiation as well as increasing shipping activities. Considering the ecological importance of marine viruses, it is timely to study the impact of UV-AB on Arctic phytoplankton host–virus interactions and also test the efficacy of ballast water (BW) UV-C treatment on virus infectivity. This study examined the effects of:(i) ecologically relevant doses of UV-AB radiation on Micromonas polaris RCC2258 and its virus MpoV-45T, and (ii) UV-C radiation (doses 25–800 mJ cm−2) on MpoV-45T and other temperate algal viruses. Total UV-AB exposure was 6, 12, 28 and 48 h (during the light periods, over 72 h total). Strongest reduction in algal growth and photosynthetic efficiency occurred for 28 and 48 h UV-AB treatments, and consequently the virus production rates and burst sizes were reduced by more than half (compared with PAR-only controls). For the shorter UV-AB exposed cultures, negative effects by UV (especially Fv/Fm) were overcomewithout impacting virus proliferation. To obtain the BW desired log −4 reduction in virus infectivity, a UV-C dose of at least 400 mJ cm−2 was needed for MpoV-45T and the temperate algal viruses. This is higher than the commonly used dose of 300 mJ cm−2 in BW treatment. View Full-Text

Background About 4-10% of patients with renal cell carcinoma (RCC) demonstrate intracaval tumor thrombi at the time of diagnosis. Furthermore, 2-3% of patients might develop local relapses of which intracaval recurrences represent a rare event with fewer than 15 cases reported in the literature. We report the diagnosis, surgical technique, perioperative complications, and oncological outcome in an additional 6 cases. Patients and methods Between 2008 and 2019, 6 patients were treated with isolated intracaval relapse of RCC. All patients had undergone radical nephrectomy with thrombectomy in the past. The mean time between first surgery and relapse was 45.2 (6-114) months and the mean age of patients was 75 (70-80) years: 2, 3 and 1 patient demonstrated thrombus level II, III, and IV, respectively. A thoracoabdominal and a transperitoneal surgical approach was chosen in 4 and 2 patients, respectively. Perioperative complications were reported according to the Clavien-Dindo classification. Relapse-free, cancer-specific and overall survival were calculated with the Kaplan-Meier method. Results The cava thrombus could be resected completely in all cases. The mean time of surgery was 330 (260-510) min and the mean blood loss was 1500 (300-6500) ml. Clavien-Dindo grade II and IV complications developed in 2 and 1 patients, respectively. The 90-day readmission rate and mortality were 0%. After a mean follow-up of 32.3 (6-96) months, 5 patients are relapse-free and 1 patient developed pulmonary and hepatic metastases managed by immuno-oncological therapy. One patient died 27 months postoperatively due to multiple myeloma. Conclusion Secondary thrombectomy for isolated intracaval tumor thrombus relapse represents a challenging surgery which is associated with a high oncological control rate and tolerable surgery-related morbidity. This type of surgery should be performed in centres with significant expertise in radical nephrectomy for locally advanced disease and thrombus su