From feces to data: A metabarcoding method for analyzing consumed and available prey in a bird‐insect food web

Diets play a key role in understanding trophic interactions. Knowing the actual structure of food webs contributes greatly to our understanding of biodiversity and ecosystem functioning. The research of prey preferences of different predators requires knowledge not only of the prey consumed, but also of what is available. In this study, we applied DNA metabarcoding to analyze the diet of 4 bird species (willow tits Poecile montanus, Siberian tits Poecile cinctus, great tits Parus major and blue tits Cyanistes caeruleus) by using the feces of nestlings. The availability of their assumed prey (Lepidoptera) was determined from feces of larvae (frass) collected from the main foraging habitat, birch (Betula spp.) canopy. We identified 53 prey species from the nestling feces, of which 11 (21%) were also detected from the frass samples (eight lepidopterans). Approximately 80% of identified prey species in the nestling feces represented lepidopterans, which is in line with the earlier studies on the parids' diet. A subsequent laboratory experiment showed a threshold for fecal sample size and the barcoding success, suggesting that the smallest frass samples do not contain enough larval DNA to be detected by high‐throughput sequencing. To summarize, we apply metabarcoding for the first time in a combined approach to identify available prey (through frass) and consumed prey (via nestling feces), expanding the scope and precision for future dietary studies on insectivorous birds.</p

Effects of hospital facilities on patient outcomes after cancer surgery: an international, prospective, observational study

Background Early death after cancer surgery is higher in low-income and middle-income countries (LMICs) compared with in high-income countries, yet the impact of facility characteristics on early postoperative outcomes is unknown. The aim of this study was to examine the association between hospital infrastructure, resource availability, and processes on early outcomes after cancer surgery worldwide.Methods A multimethods analysis was performed as part of the GlobalSurg 3 study-a multicentre, international, prospective cohort study of patients who had surgery for breast, colorectal, or gastric cancer. The primary outcomes were 30-day mortality and 30-day major complication rates. Potentially beneficial hospital facilities were identified by variable selection to select those associated with 30-day mortality. Adjusted outcomes were determined using generalised estimating equations to account for patient characteristics and country-income group, with population stratification by hospital.Findings Between April 1, 2018, and April 23, 2019, facility-level data were collected for 9685 patients across 238 hospitals in 66 countries (91 hospitals in 20 high-income countries; 57 hospitals in 19 upper-middle-income countries; and 90 hospitals in 27 low-income to lower-middle-income countries). The availability of five hospital facilities was inversely associated with mortality: ultrasound, CT scanner, critical care unit, opioid analgesia, and oncologist. After adjustment for case-mix and country income group, hospitals with three or fewer of these facilities (62 hospitals, 1294 patients) had higher mortality compared with those with four or five (adjusted odds ratio [OR] 3.85 [95% CI 2.58-5.75]; p&lt;0.0001), with excess mortality predominantly explained by a limited capacity to rescue following the development of major complications (63.0% vs 82.7%; OR 0.35 [0.23-0.53]; p&lt;0.0001). Across LMICs, improvements in hospital facilities would prevent one to three deaths for every 100 patients undergoing surgery for cancer.Interpretation Hospitals with higher levels of infrastructure and resources have better outcomes after cancer surgery, independent of country income. Without urgent strengthening of hospital infrastructure and resources, the reductions in cancer-associated mortality associated with improved access will not be realised

Impact of an institutional change from routine to highly selective diversion of a low anastomosis after TME for rectal cancer

Introduction: The need for routine diverting ileostomy following restorative total mesorectal excision (TME) is increasingly debated as the benefits might not outweigh the disadvantages. This study evaluated an institutional shift from routine (RD) to highly selective diversion (HSD) after TME surgery for rectal cancer. Materials and methods: Patients having TME with primary anastomosis and HSD for low or mid rectal cancer between December 2014 and March 2017 were compared with a historical control group with RD in the preceding period since January 2011. HSD was introduced in conjunction with uptake of transanal TME. Results: In the RD group, 45/50 patients (90%) had a primary diverting stoma, and 3/40 patients (8%) in the HSD group. Anastomotic leakage occurred in 10 (20%) and three (8%) cases after a median follow-up of 36 and 19 months after RD and HSD, respectively. There was no postoperative mortality. An unintentional stoma beyond 1 year postoperative was present in six and two patients, respectively. One-year stoma-related readmission and reoperation rate (including reversal) after RD were 84% and 86%, respectively. Corresponding percentages were significantly lower after HSD (17% and 17%; P < 0.001). Total hospital stay within one year was median 11 days (IQR 8–19) versus 5 days (IQR 4–11), respectively (P < 0.001). Conclusion: This single institutional comparative cohort study shows that highly selective defunctioning of a low anastomosis in rectal cancer patients did not adversely affect incidence or consequences of anastomotic leakage with a substantial decrease in 1-year readmission and reintervention rate, leading to an overall significantly reduced hospital stay

Nitrogen vacancy complexes in nitrogen irradiated metals

Gas desorption and positron annihilation techniques have been employed to study the evolution of nitrogen associated defects in nitrogen irradiated metals: Fe, Ni, Mo and W. Nitrogen in these metals has a rather high affinity to vacancy type defects. The results obtained for low irradiation dose show that substitutional nitrogen (NV; with V = vacancy) is formed. The nitrogen vacancy complex dissociates at temperatures ranging from 350 K for Ni to 900 K for Mo and 1,100 K for W. At high doses defects are formed which can be characterized as nitrogen saturated vacancy clusters. These defect, as observed by helium probing, disappear during annealing for nickel at 800 K, and for Mo at 1,100 K. The direct observation of the desorbing nitrogen for nickel and molybdenum reveals a very fast desorption transient at the dissociation temperature of the clusters. This is the characteristic desorption transient of a small nitride cluster, e.g., by shrinkage with constant rate. For iron the nitrogen desorption is more complicated because of a general background that continuously rises with temperature. With the positron beam technique depth information was obtained for defects in iron and the defect character could be established with the help of the information provided on annihilation with conduction and core electrons of the defect trapped positrons

Redo coloanal anastomosis for anastomotic leakage after low anterior resection for rectal cancer: an analysis of 59 cases

AimThe construction of a new coloanal anastomosis (CAA) following anastomotic leakage after low anterior resection (LAR) is challenging. The available literature on this topic is scarce. The aim of this two-centre study was to determine the clinical success and morbidity after redo CAA. MethodThis retrospective cohort study included all patients with anastomotic leakage after LAR for rectal cancer who underwent a redo CAA between 2010 and 2014 in two tertiary referral centres. Short- and long-term morbidity were analysed, including both anastomotic leakage and permanent stoma rates on completion of follow-up. ResultsA total of 59 patients were included, of whom 45 (76%) were men, with a mean age of 59years (SD9.4). The median interval between index and redo surgery was 14months [interquartile range (IQR) 8-27]. The median duration of follow-up was 27months (IQR 17-36). The most frequent complication was anastomotic leakage of the redo CAA occurring in 24 patients (41%), resulting in a median of three reinterventions (IQR 2-4) per patient. At the end of follow-up, bowel continuity was restored in 39/59 (66%) patients. Fourteen (24%) patients received a definitive colostomy and six (10%) still had a diverting ileostomy. In a multivariable model, leakage of the redo CAA was the only risk factor for permanent stoma (OR 0.022; 95% CI 0.004-0.122). ConclusionRedo CAA is a viable option in selected patients with persisting leakage after LAR for rectal cancer who want their bowel continuity restored. However, patients should be fully informed about the relatively high morbidity and reintervention rate