Late Winter Biogeochemical Conditions Under Sea Ice in the Canadian High Arctic

With the Arctic summer sea-ice extent in decline, questions are arising as to how changes in sea-ice dynamics might affect biogeochemical cycling and phenomena such as carbon dioxide (CO2) uptake and ocean acidification. Recent field research in these areas has concentrated on biogeochemical and CO2 measurements during spring, summer or autumn, but there are few data for the winter or winter–spring transition, particularly in the High Arctic. Here, we present carbon and nutrient data within and under sea ice measured during the Catlin Arctic Survey, over 40 days in March and April 2010, off Ellef Ringnes Island (78° 43.11′ N, 104° 47.44′ W) in the Canadian High Arctic. Results show relatively low surface water (1–10 m) nitrate (<1.3 µM) and total inorganic carbon concentrations (mean±SD=2015±5.83 µmol kg−1), total alkalinity (mean±SD=2134±11.09 µmol kg−1) and under-ice pCO2sw (mean±SD=286±17 µatm). These surprisingly low wintertime carbon and nutrient conditions suggest that the outer Canadian Arctic Archipelago region is nitrate-limited on account of sluggish mixing among the multi-year ice regions of the High Arctic, which could temper the potential of widespread under-ice and open-water phytoplankton blooms later in the season

Optimal Perioperative Care in Major Head and Neck Cancer Surgery With Free Flap Reconstruction: A Consensus Review and Recommendations From the Enhanced Recovery After Surgery Society.

Head and neck cancers often require complex, labor-intensive surgeries, especially when free flap reconstruction is required. Enhanced recovery is important in this patient population but evidence-based protocols on perioperative care for this population are lacking. To provide a consensus-based protocol for optimal perioperative care of patients undergoing head and neck cancer surgery with free flap reconstruction. Following endorsement by the Enhanced Recovery After Surgery (ERAS) Society to develop this protocol, a systematic review was conducted for each topic. The PubMed and Cochrane databases were initially searched to identify relevant publications on head and neck cancer surgery from 1965 through April 2015. Consistent key words for each topic included "head and neck surgery," "pharyngectomy," "laryngectomy," "laryngopharyngectomy," "neck dissection," "parotid lymphadenectomy," "thyroidectomy," "oral cavity resection," "glossectomy," and "head and neck." The final selection of literature included meta-analyses and systematic reviews as well as randomized controlled trials where available. In the absence of high-level data, case series and nonrandomized studies in head and neck cancer surgery patients or randomized controlled trials and systematic reviews in non-head and neck cancer surgery patients, were considered. An international panel of experts in major head and neck cancer surgery and enhanced recovery after surgery reviewed and assessed the literature for quality and developed recommendations for each topic based on the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) system. All recommendations were graded following a consensus discussion among the expert panel. The literature search, including a hand search of reference lists, identified 215 relevant publications that were considered to be the best evidence for the topic areas. A total of 17 topic areas were identified for inclusion in the protocol for the perioperative care of patients undergoing major head and neck cancer surgery with free flap reconstruction. Best practice includes several elements of perioperative care. Among these elements are the provision of preoperative carbohydrate treatment, pharmacologic thromboprophylaxis, perioperative antibiotics in clean-contaminated procedures, corticosteroid and antiemetic medications, short acting anxiolytics, goal-directed fluid management, opioid-sparing multimodal analgesia, frequent flap monitoring, early mobilization, and the avoidance of preoperative fasting. The evidence base for specific perioperative care elements in head and neck cancer surgery is variable and in many cases information from different surgerical procedures form the basis for these recommendations. Clinical evaluation of these recommendations is a logical next step and further research in this patient population is warranted

Sky service: the demands of emotional labour in the airline industry

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