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Floodplains represent critical nursery habitats for a variety of fish species due to their highly productive food webs, yet few tools exist to quantify the extent to which these habitats contribute to ecosystem-level production. Here we conducted a large-scale field experiment to characterize differences in food web composition and stable isotopes (δ¹³C, δ¹⁵N, δ³⁴S) for salmon rearing on a large floodplain and adjacent river in the Central Valley, California, USA. The study covered variable hydrologic conditions including flooding (1999, 2017), average (2016), and drought (2012-2015). In addition, we determined incorporation rates and tissue fractionation between prey and muscle from fish held in enclosed locations (experimental fields, cages) at weekly intervals. Finally, we measured δ³⁴S in otoliths to test if these archival biominerals could be used to reconstruct floodplain use. Floodplain-reared salmon had a different diet composition and lower δ13C and δ³⁴S (δ¹³C = -33.02±2.66‰, δ³⁴S = -3.47±2.28‰; mean±1SD) compared to fish in the adjacent river (δ¹³C = -28.37±1.84‰, δ³⁴S = +2.23±2.25‰). These isotopic differences between habitats persisted across years of extreme droughts and floods. Despite the different diet composition, δ¹⁵N values from prey items on the floodplain (δ¹⁵N = 7.19±1.22‰) and river (δ¹⁵N = 7.25±1.46‰) were similar, suggesting similar trophic levels. The food web differences in δ13C and δ³⁴S between habitats were also reflected in salmon muscle tissue, reaching equilibrium between 24-30 days (2014, δ¹³C = -30.74±0.73‰, δ³⁴S = -4.6±0.68‰; 2016, δ¹³C = -34.74 ±0.49‰, δ³⁴S = -5.18±0.46‰). δ³⁴S measured in sequential growth bands in otoliths recorded a weekly time-series of shifting diet inputs, with the outermost layers recording time spent on the floodplain (δ³⁴S = -5.60±0.16‰) and river (δ³⁴S = 3.73±0.98‰). Our results suggest that δ¹³C and δ³⁴S can be used to differentiate floodplain and river rearing habitats used by native fishes, such as Chinook Salmon, across different hydrologic conditions and tissues. Together these stable isotope analyses provide a toolset to quantify the role of floodplains as fish habitats.

Summary: Background: The 7th National Audit Project of the Royal College of Anaesthetists studied peri‐operative cardiac arrest because of existing knowledge gaps in this important topic. This applies in particular to cardiology patients receiving anaesthetic care, because numbers, types and complexity of minimally invasive interventional procedures requiring planned and unplanned anaesthesia in the cardiac intervention suite is increasing. Methods: We analysed collected data to determine the epidemiology, clinical features, management and outcomes of peri‐operative cardiac arrest in adult patients receiving anaesthetic care for cardiology procedures. Results: There were 54 reports of peri‐operative cardiac arrest in adult patients receiving anaesthetic care for cardiology procedures, accounting for 54/881 (6.1%) of all reports to NAP7. The estimated incidence (95%CI) of cardiac arrests in this group was 1/450 or 0.22 (0.17–0.29)%. These patients were older than other adult patients in the NAP7 population, with a notably high proportion of patients of Asian ethnicity when compared with the remaining NAP7 cohort (9/54, 17% vs. 35/709, 5%). Rates of extracorporeal membrane oxygenation cardiopulmonary resuscitation were low (3/53, 6%). A common theme was that of logistical issues and teamworking, with reporters commenting on the difficulties of remote and/or unfamiliar locations and communication issues between specialties, on occasion resulting in poor teamworking and a lack of focus. The NAP7 panel review identified several other common themes which included: cardiogenic shock; late involvement of anaesthesia in the case; and transcatheter aortic valve implantation. Conclusion: Cardiology procedures requiring anaesthesia care account for < 1% of anaesthesia activity but generate 6% of all peri‐operative cardiac arrests. The incidence of cardiac arrest was disproportionately high in cardiological procedures requiring anaesthetic care. The nature of the cardiac arrest reports to NAP7 indicate that logistical and human factors in multidisciplinary teams in the cardiac intervention suite merit addressing to improve care. [ABSTRACT FROM AUTHOR]

Shwachman–Diamond syndrome (SDS) is an inherited bone marrow failure disorder that often presents at infancy. Progress has been made in revealing causal mutated genes (SBDS and others), ribosome defects, and hematopoietic aberrations in SDS. However, the mechanism underlying the hematopoietic failure remained unknown, and treatment options are limited. Herein, we investigated the onset of SDS embryonic hematopoietic impairments. We generated SDS and control human‐derived induced pluripotent stem cells (iPSCs). SDS iPSCs recapitulated the SDS hematological phenotype. Detailed stepwise evaluation of definitive hematopoiesis revealed defects that started at the early emerging hematopoietic progenitor (EHP) stage after mesoderm and hemogenic endothelium were normally induced. Hematopoietic potential of EHPs was markedly reduced, and the introduction of SBDS in SDS iPSCs improved colony formation. Transcriptome analysis revealed reduced expression of ribosome and oxidative phosphorylation‐related genes in undifferentiated and differentiated iPSCs. However, certain pathways (e.g., DNA replication) and genes (e.g., CHCHD2) were exclusively or more severely dysregulated in EHPs compared with earlier and later stages. To our knowledge, this study offers for the first time an insight into the embryonic onset of human hematopoietic defects in an inherited bone marrow failure syndrome and reveals cellular and molecular aberrations at critical stages of hematopoietic development toward EHPs. [ABSTRACT FROM AUTHOR]

Summary: Background: We analysed the clinical practice of anaesthesia associates in the UK, as reported to the 7th National Audit Project of the Royal College of Anaesthetists, and compared these with medically qualified anaesthetists. Methods: We included data from our baseline survey, activity survey and case registry as with other reports from the project. Results: Among 197 departments of anaesthesia, 52 (26%) employed anaesthesia associates. Of 10,009 responding anaesthesia care providers, 71 (< 1%) were anaesthesia associates, of whom 33 (47%) reporting working nights or weekends (compared with 97% of medically qualified anaesthetists in training and > 90% of consultants). Anaesthesia associates reported less training and confidence in managing peri‐operative cardiac arrest and its aftermath compared with medically qualified anaesthetists. Anaesthesia associates were less directly involved in the management and the aftermath of peri‐operative cardiac arrest than medically qualified anaesthetists, and the psychological impacts on professional and personal life appeared to be less. Among 24,172 cases, anaesthesia associates attended 432 (2%) and were the senior anaesthesia care provider in 63 (< 1%), with indirect supervision in 27 (43%). Anaesthesia associates worked predominantly in a small number of surgical specialties during weekdays and working daytime hours. Complication rates were low in cases managed by anaesthesia associates, likely reflecting case mix. However, activity and registry case mix data show anaesthesia associates do manage high‐risk cases (patients who are older, comorbid, obese and frail) with the potential for serious complications. Registry cases included higher risk cases with respect to the clinical setting and patient factors. Conclusion: Anaesthesia associates work in enhanced roles, relative to the scope of practice at qualification agreed by organisations. Recent changes mean the Royal College of Anaesthetists and Association of Anaesthetists do not currently support an enhanced scope of practice. [ABSTRACT FROM AUTHOR]

Summary: Background: Few existing resuscitation guidelines include specific reference to intra‐operative cardiac arrest, but its optimal treatment is likely to require some adaptation of standard protocols. Methods: We analysed data from the 7th National Audit Project of the Royal College of Anaesthetists to determine the incidence and outcome from intra‐operative cardiac arrest and to summarise the advanced life support interventions reported as being used by anaesthetists. Results: In the baseline survey, > 50% of anaesthetists responded that they would start chest compressions when the non‐invasive systolic pressure was < 40–50 mmHg. Of the 881 registry patients, 548 were adult patients (aged > 18 years) having non‐obstetric procedures under the care of an anaesthetist, and who had arrested during anaesthesia (from induction to emergence). Sustained return of spontaneous circulation was achieved in 425 (78%) patients and 338 (62%) were alive at the time of reporting. In the 365 patients with pulseless electrical activity or bradycardia, adrenaline was given as a 1 mg bolus in 237 (65%). A precordial thump was used in 14 (3%) patients, and although this was associated with return of spontaneous circulation at the next rhythm check in almost three‐quarters of patients, in only one of these was the initial rhythm shockable. Calcium (gluconate or chloride) and 8.4% sodium bicarbonate were given to 51 (9%) and 25 (5%) patients, but there were specific indications for these treatments in less than half of the patients. A thrombolytic drug was given to 5 (1%) patients, and extracorporeal cardiopulmonary resuscitation was used in 9 (2%) of which eight occurred during cardiac procedures. Conclusions: The specific characteristics of intra‐operative cardiac arrest imply that its optimal treatment requires modifications to standard advanced life support guidelines. [ABSTRACT FROM AUTHOR]

The use of coffins and jars as funerary receptacles was common across Southeast Asia. During the fifteenth to seventeenth centuries AD, cremation was the dominant mortuary tradition on the Angkorian plains, but in the Cardamom Mountains to the south, contemporaneous groups practised a unique burial tradition involving the deposition of un-cremated bone in exposed ceramic vessels and log coffins. The authors present the first geochemical analysis of individuals from this highland culture, specifically the site of Phnom Pel. The childhood diets of those interred in jars and coffins may have been sourced from different areas within the Cardamom Mountains, suggesting that the individuals came from discrete groups. Keywords: Southeast Asia, Cardamom Mountains, mortuary traditions, mobility, strontium isotopes, Introduction Compared to the contemporaneous lowland Khmer cultures, little is known about the fifteenth--to seventeenth-century AD highland communities of the Cardamom Mountains of southern Cambodia. Archaeologically, they are characterised by [...]